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Acetylshikonin (AS) is an active component of Lithospermum erythrorhizon Sieb. et Zucc that exhibits activity against various cancers; however, the underlying mechanisms of AS against oesophageal squamous carcinoma (ESCC) need to be elusive. The research explores the anti-cancer role and potential mechanism of AS on ESCC in vitro and in vivo, providing evidences for AS treatment against ESCC. In this study, we firstly demonstrated that AS treatment effectively inhibits cell viability and proliferation of ESCC cells. In addition, AS significantly induces G1/S phage arrest and promotes apoptosis in ESCC cell lines. Further studies reveal that AS induces ER stress, as observed by dose- and time-dependently increased expression of BIP, PDI, PERK, phosphorylation of eIF2α , CHOP and splicing of XBP1. CHOP knockdown or PERK inhibition markedly rescue cell apoptosis induced by AS. Moreover, AS treatment significantly inhibits ESCC xenograft growth in nude mice. Elevated expression of BIP and CHOP is also observed in xenograft tumours. Taken together, AS inhibits proliferation and induces apoptosis through ER stress-activated PERK/eIF2α /CHOP pathway in ESCC, which indicates AS represents a promising candidate for ESCC treatment.

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BACKGROUND: Traditional problem-based learning (PBL) relying on tutored learning in small groups is very resource-intensive. Little is known about the benefits of PBL in a large classroom setting. This paper introduced a PBL case into the traditional didactic biochemistry course and investigated the acceptability of total online or partial online PBL in a large classroom setting introduced during the coronavirus pandemic. METHODS: The students were allocated into either total online Group 1, partial online Group 2, or partial online and with poorer academic performance Group 3. A questionnaire comprising of 8 closed-ended questions and 2 open-ended questions and final exam performances were used to evaluate the acceptability of total online or partial online PBL in a large classroom setting. The 8 closed-ended questions were analysed by the Kruskal-Wallis test or chi-square tests. The word cloud analysis of the 2 open-ended questions were conducted by Wenjuanxing. Students' performances in the final examination were analysed by One-way Anova. RESULTS: Both total online and partial online PBL were rated highly by the students. Overall, there were no significant differences in the effectiveness evaluation of PBL between Group 2 and Group 3. There were no significant differences in final exam performances between Group 1 and Group 2. However, Group 1 rated the effectiveness of PBL much higher than Group 2 and 3. Word cloud analysis of the 2 open-ended questions showed students' positive perspectives of PBL. In biochemistry teaching, from the perspective of the students, the expected optimal number of useful PBL cases might be 2. CONCLUSIONS: Both total online and partial online PBL in a large classroom setting were widely accepted as a beneficial supplement to traditional biochemistry classes.

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The malignant lung cancer has a high morbidity rate and very poor 5-year survival rate. About 80% - 90% of protein degradation in human cells is occurred through the ubiquitination enzyme pathway. Ubiquitin ligase (E3) with high specificity plays a crucial role in the ubiquitination process of the target protein, which usually occurs at a lysine residue in a substrate protein. Different ubiquitination forms have different effects on the target proteins. Multiple short chains of ubiquitination residues modify substrate proteins, which are favorable signals for protein degradation. The dynamic balance adapted to physiological needs between ubiquitination and deubiquitination of intracellular proteins is beneficial to the health of the organism. Ubiquitination of proteins has an impact on many biological pathways, and imbalances in these pathways lead to diseases including lung cancer. Ubiquitination of tumor suppressor protein factors or deubiquitination of tumor carcinogen protein factors often lead to the progression of lung cancer. Ubiquitin proteasome system (UPS) is a treasure house for research and development of new cancer drugs for lung cancer, especially targeting proteasome and E3s. The ubiquitination and degradation of oncogene proteins with precise targeting may provide a bright prospect for drug development in lung cancer; Especially proteolytic targeted chimerism (PROTAC)-induced protein degradation technology will offer a new strategy in the discovery and development of new drugs for lung cancer.

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BACKGROUND: The prognosis of patients with colorectal cancer is related to early detection. However, commonly used screening markers lack sensitivity and specificity. In this study, we identified diagnostic methylation sites for colorectal cancer. METHODS: After screening the colorectal cancer methylation dataset, diagnostic sites were identified via survival analysis, difference analysis, and ridge regression dimensionality reduction. The correlation between the selected methylation sites and the estimation of immune cell infiltration was analyzed. The accuracy of the diagnosis was verified using different datasets and the 10-fold crossover method. RESULTS: According to Gene Ontology, the main enrichment pathways of genes with hypermethylation sites are axon development, axonogenesis, and pattern specification processes. However, the Kyoto Encyclopedia of Genes and Genomes (KEGG) suggests the following main enrichment pathways: neuroactive ligand-receptor interaction, calcium signaling, and cAMP signaling. In The Cancer Genome Atlas (TCGA) and GSE131013 datasets, the area under the curve of cg07628404 was > 0.95. For the NaiveBayes machine model of cg02604524, cg07628404, and cg27364741, the accuracies of 10-fold cross-validation in the GSE131013 and TCGA datasets were 95% and 99.4%, respectively. The survival prognosis of the hypomethylated group (cg02604524, cg07628404, and cg27364741) was better than that of the hypermethylated group. The mutation risk did not differ between the hypermethylated and hypomethylated groups. The correlation coefficient between the three loci and CD4 central memory T cells, hematological stem cells, and other immune cells was not high (p < 0.05). CONCLUSION: In cases of colorectal cancer, the main enrichment pathway of genes with hypermethylated sites was axon and nerve development. In the biopsy tissues, the hypermethylation sites were diagnostic for colorectal cancer, and the NaiveBayes machine model of the three loci showed good diagnostic performance. Site (cg02604524, cg07628404, and cg27364741) hypermethylation predicts poor survival for colorectal cancer. Three methylation sites were weakly correlated with individual immune cell infiltration. Hypermethylation sites may be a useful repository for diagnosing colorectal cancer.

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Three-dimensional printing models (3DPs) have been widely used in medical anatomy training. However, the 3DPs evaluation results differ depending on such factors as the training objects, experimental design, organ parts, and test content. Thus, this systematic evaluation was carried out to better understand the role of 3DPs in different populations and different experimental designs. Controlled (CON) studies of 3DPs were retrieved from PubMed and Web of Science databases, where the participants were medical students or residents. The teaching content is the anatomical knowledge of human organs. One evaluation indicator is the mastery of anatomical knowledge after training, and the other is the satisfaction of participants with 3DPs. On the whole, the performance of the 3DPs group was higher than that of the CON group; however, there was no statistical difference in the resident subgroup, and there was no statistical difference for 3DPs vs. 3D visual imaging (3DI). In terms of satisfaction rate, the summary data showed that the difference between the 3DPs group (83.6%) vs. the CON group (69.6%) (binary variable) was not statistically significant, with p > 0.05. 3DPs has a positive effect on anatomy teaching, although there are no statistical differences in the performance tests of individual subgroups; participants generally had good evaluations and satisfaction with 3DPs. 3DPs still faces challenges in production cost, raw material source, authenticity, durability, etc. The future of 3D-printing-model-assisted anatomy teaching is worthy of expectation.

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Acetylshikonin (ASK) is a natural naphthoquinone derivative of traditional Chinese medicine Lithospermum erythrorhyzon. It has been reported that ASK has bactericidal, anti-inflammatory and antitumour effects. However, whether ASK induces apoptosis and autophagy in acute myeloid leukaemia (AML) cells and the underlying mechanism are still unclear. Here, we explored the roles of apoptosis and autophagy in ASK-induced cell death and the potential molecular mechanisms in human AML HL-60 cells. The results demonstrated that ASK remarkably inhibited the cell proliferation, viability and induced apoptosis in HL-60 cells through the mitochondrial pathway, and ASK promoted cell cycle arrest in the S-phase. In addition, the increased formation of autophagosomes, the turnover from light chain 3B (LC3B) I to LC3B II and decrease of P62 suggested the induction of autophagy by ASK. Furthermore, ASK significantly decreased PI3K, phospho-Akt and p-p70S6K expression, while enhanced phospho-AMP-activated protein kinase (AMPK) and phospho-liver kinase B1(LKB1) expression. The suppression of ASK-induced the conversion from LC3B I to LC3B II caused by the application of inhibitors of AMPK (compound C) demonstrated that ASK-induced autophagy depends on the LKB1/AMPK pathway. These data suggested that the autophagy induced by ASK were dependent on the activation of LKB1/AMPK signalling and suppression of PI3K/Akt/mTOR pathways. The cleavage of the apoptosis-related markers caspase-3 and caspase-9 and the activity of caspase-3 induced by ASK were markedly reduced by inhibitor of AMPK (compound C), an autophagy inhibitor 3-methyladenine (3-MA) and another autophagy inhibitor chloroquine (CQ). Taken together, our data reveal that ASK-induced HL-60 cell apoptosis is dependent on the activation of autophagy via the LKB1/AMPK and PI3K/Akt-regulated mTOR signalling pathways.

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Polymyxin is regarded as the last retort to fight against multidrug-resistant (MDR) Enterobacteriaceae. The emergency and spread of polymyxin-associated resistance gene mcr-1 evoked great panic of no medicine to cure the bacterial infection in society. mcr-1 is widespread in domestic and wild animals. Therefore, continuous monitoring of its prevalence and characteristics is required. In this study, we used a polymerase chain reaction (PCR)-based method to detect the mcr-1 of Escherichia coli isolated from rabbits of Tai'an, China, and determined the characteristics of mcr-1-bearing plasmids. A total of 55 non-duplicated E. coli was recovered from the swabs of rabbit faeces. Plasmid profiling, plasmid and chromosome PCR, complete genome sequencing, a conjugation experiment, lactose fermentation experiment, multilocus sequence typing and polymyxin resistance tests were performed to determine the characteristics of mcr-1-bearing plasmids. 14.6% (8/55) of the specimens were mcr-1 positive. The mcr-1-positive E. coli harboured more drug-resistant genes compared with the mcr-1-negative specimens, and results showed four sequence types. Overall, these findings suggested the possible threat of the transmission of mcr-1 from rabbits to humans, especially since the gene is located on transferable plasmids making horizontal transfer relatively easy. Since food-producing animals are necessary for our daily diet, worldwide cooperation is needed in fighting the spread of this drug resistance gene to avoid human infections with MDR pathogenic bacteria.

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BACKGROUND: Three-dimensional (3D) printing is an emerging technology widely used in medical education. However, its role in the teaching of human anatomy needs further evaluation. METHODS: PubMed, Embase, EBSCO, SpringerLink, and Nature databases were searched systematically for studies published from January 2011 to April 2020 in the English language. GRADEprofiler software was used to evaluate the quality of literature. In this study, a meta-analysis of continuous and binary data was conducted. Both descriptive and statistical analyses were used. RESULTS: Comparing the post-training tests in neuroanatomy, cardiac anatomy, and abdominal anatomy, the standardized mean difference (SMD) of the 3D group and the conventional group were 1.27, 0.37, and 2.01, respectively (p < 0.05). For 3D vs. cadaver and 3D vs. 2D, the SMD were 0.69 and 1.05, respectively (p < 0.05). For answering time, the SMD of the 3D group vs. conventional group was - 0.61 (P < 0.05). For 3D print usefulness, RR = 2.29(P < 0.05). Five of the six studies showed that satisfaction of the 3D group was higher than that of the conventional group. Two studies showed that accuracy of answering questions in the 3D group was higher than that in the conventional group. CONCLUSIONS: Compared with students in the conventional group, those in the 3D printing group had advantages in accuracy and answering time. In the test of anatomical knowledge, the test results of students in the 3D group were not inferior (higher or equal) to those in the conventional group. The post-training test results of the 3D group were higher than those in the cadaver or 2D group. More students in the 3D printing group were satisfied with their learning compared with the conventional group. The results could be influenced by the quality of the randomized controlled trials. In a framework of ethical rigor, the application of the 3D printing model in human anatomy teaching is expected to grow further.

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Oesophageal cancer is one of the most frequent solid malignancies and the leading cause of cancer-related death around the world. It is urgent to develop novel therapy strategies to improve patient outcomes. Acetylation modification of histones has been extensively studied in epigenetics. BRD4, a reader of acetylated histone and non-histone proteins, has involved in tumorigenesis. It has emerged as a promising target for cancer therapy. BRD4 inhibitors, such as JQ1, have exerted efficacious anti-proliferation activities in diverse cancers. However, the effects of JQ1 on oesophageal cancer are still not fully described. Here, we demonstrate that JQ1 suppresses cell growth and triggers cellular senescence in KYSE450 cells. Mechanistically, JQ1 up-regulates p21 level and decreases cyclin D1 resulting in G1 cycle arrest. The inhibitory effects of JQ1 on KYSE450 cells are independent on apoptosis. It activates cellular senescence by increasing SA-ß-gal activity. BRD4 knockdown by shRNA recapitulates cellular senescence. We also display that administration of JQ1 decreases recruitment of BRD4 on the promoter of aurora kinases A and B. Inhibitors targeting at AURKA/B phenocopy JQ1 treatment in KYSE450 cells. These results identify a novel action manner of BRD4 in oesophageal cancer, which strengthens JQ1 as a candidate drug in oesophageal cancer chemotherapy.

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Acetylshikonin, a natural naphthoquinone derivative compound from Lithospermum erythrorhyzon, has been reported to kill bacteria, suppress inflammation, and inhibit tumor growth. However, the effect of acetylshikonin on human chronic myelocytic leukemia (CML) cells apoptosis and its detailed mechanisms remains unknown. The purpose of the present study was to investigate whether acetylshikonin could inhibit proliferation or induce apoptosis of the K562 cells, and whether by regulating the NF-κB signaling pathway to suppress the development of CML. K562 cells were treated with serial diluted acetylshikonin at different concentrations. Our data showed that K562 cell growth was significantly inhibited by acetylshikonin with an IC50 of 2.03 µM at 24 h and 1.13 µM at 48 h, with increased cell cycle arrest in S-phase. The results of annexin V-FITC/PI and AO/EB staining showed that acetylshikonin induced cell apoptosis in a dose-dependent manner. K562 cells treated with acetylshikonin underwent massive apoptosis accompanied by a rapid generation of reactive oxygen species (ROS). Scavenging the ROS completely blocked the induction of apoptosis following acetylshikonin treatment. The levels of the pro-apoptotic proteins Bax, cleaved caspase-9, cleaved PARP and cleaved caspase-3 increased with increased concentrations of acetylshikonin, while the level of the anti-apoptotic protein Bcl-2 was downregulated. The levels of Cyt C and AIF, which are characteristic proteins of the mitochondria-regulated intrinsic apoptotic pathway, also increased in the cytosol after acetylshikonin treatment. However, the mitochondrial fraction of Cyt C and AIF were decreased under acetylshikonin treatment. In addition, acetylshikonin decreased Bcr-Abl expression and inhibited its downstream signaling. Acetylshikonin could lead to a blockage of the NF-κB signaling pathway via decreasing nuclear NF-κB P65 and increasing cytoplasmic NF-κB P65. Moreover, acetylshikonin significantly inhibited the phosphorylation of IkBα and IKKα/ß in K562 cells. These results demonstrated that acetylshikonin significantly inhibited K562 cell growth and induced cell apoptosis through the mitochondria-regulated intrinsic apoptotic pathway. The mechanisms may involve the modulating ROS accumulation, inhibition of NF-κB and BCR-ABL expression. The inhibition of BCR-ABL expression and the inactivation of the NF-κB signaling pathway caused by acetylshikonin treatment resulted in K562 cell apoptosis. Together, our results indicate that acetylshikonin could serve as a potential therapeutic agent for the future treatment of CML.

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Doxorubicin (DOX) as a first-line chemotherapeutic drug has been widely used for therapy of human cancers. However, side effects and chemo-resistance severely blocked its clinic application. Herein, natural borneol (NB) as a novel monoterpenoid chemosensitizer was found to have the potential to increase the blood brain barrier (BBB) permeability and intracellular uptake of DOX in vitro, and synergistically enhanced DOX-induced cytotoxicity in human glioma cells. NB treatment significantly potentiated DOX-induced G2/M cell cycle arrest by triggering reactive oxygen species (ROS)-mediated DNA damage. NB also enhanced DOX-induced dysfunction of MAPKs and PI3 K/AKT pathways. Furthermore, U251 human glioma xenograft growth in vivo was also effectively inhibited by combined treatment of DOX with NB through induction of G2/M-phase arrest and antiangiogenesis. Taken together, our finding validated that NB could act as novel chemosensitizer to enhance DOX-induced anticancer efficacy, and strategy of using NB and DOX could be a high efficient way in therapy of human cancers.

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With the expansion of Intelligent Transport Systems (ITS) in smart cities, the shared bicycle has developed quickly as a new green public transportation mode, and is changing the travel habits of citizens heavily across the world, especially in China. The purpose of the current paper is to provide an inclusive review and survey on shared bicycle besides its benefits, history, brands and comparisons. In addition, it proposes the concept of the Internet of Shared Bicycle (IoSB) for the first time, as far as we know, to find a feasible solution for those technical problems of the shared bicycle. The possible architecture of IoSB in our opinion is presented, as well as most of key IoT technologies, and their capabilities to merge into and apply to the different parts of IoSB are introduced. Meanwhile, some challenges and barriers to IoSB's implementation are expressed thoroughly too. As far as the advice for overcoming those barriers be concerned, the IoSB's potential aspects and applications in smart city with respect to technology development in the future provide another valuable further discussion in this paper.

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BACKGROUND: E2F1 transcription factor plays a vital role in the regulation of diverse cellular processes including cell proliferation, apoptosis, invasion and metastasis. E2F1 overexpression has been demonstrated in small cell lung cancer (SCLC), and extensive metastasis in early phase is the most important feature of SCLC. In this study, we investigated the involvement of E2F1 in the process of invasion and metastasis in SCLC by regulating the expression of matrix metalloproteinases (MMPs). METHODS: Immunohistochemistry was performed to evaluate the expression of E2F1 and MMPs in SCLC samples in a Chinese Han population. The impact of E2F1 on invasion and metastasis was observed by transwell and wound healing experiments with depletion of E2F1 by specific siRNA. The target genes regulated by E2F1 were identified by chromatin immunoprecipitation (ChIP)-to-sequence, and the expressions of target genes were detected by real time PCR and western blotting. The dual luciferase reporter system was performed to analyze the regulatory relationship between E2F1 and MMPs. RESULTS: E2F1 is an independent and adverse prognosis factor that is highly expressed in SCLC in a Chinese Han population. Knockdown of E2F1 by specific siRNA resulted in the downregulation of migration and invasion in SCLC. The expressions of MMP-9 and -16 in SCLC were higher than other MMPs, and their expressions were most significantly reduced after silencing E2F1. ChIP-to-sequence and promoter-based luciferase analysis demonstrated that E2F1 directly controlled MMP-16 expression via an E2F1 binding motif in the promoter. Although one E2F1 binding site was predicted in the MMP-9 promoter, luciferase analysis indicated that this binding site was not functionally required. Further study demonstrated that E2F1 transcriptionally controlled the expression of Sp1 and p65, which in turn enhanced the MMP-9 promoter activity in SCLC cells. The associations between E2F1, Sp1, p65, and MMP-9 were validated by immunohistochemistry staining in SCLC tumors. CONCLUSIONS: E2F1 acts as a transcriptional activator for MMPs and directly enhances MMP transcription by binding to E2F1 binding sequences in the promoter, or indirectly activates MMPs through enhanced Sp1 and NF-kappa B as a consequence of E2F1 activation in SCLC.

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Macrocyclic bisbibenzyls, characteristic components derived from liverworts, have various biological activities. Riccardin D (RD), a liverwort-derived naturally occurring macrocyclic bisbibenzyl, has been found to exert anticancer effects in multiple cancer cell types through apoptosis induction. However, the underlying mechanisms of such effects remain undefined. In addition, whether RD induces other forms of cell death such as autophagy is unknown. In this study, we found that the arrest of RD-caused U2OS (p53 wild) and Saos-2 (p53 null) cells in G1 phase was associated with the induction of p53 and p21(WAF1) in U2OS cells. RD-mediated cell cycle arrest was accompanied with apoptosis promotion as indicated by changes in nuclear morphology and expression of apoptosis-related proteins. Further studies revealed that the antiproliferation of RD was unaffected in the presence of p53 inhibitor but was partially reversed by a pan-inhibitor of caspases, suggesting that p53 was not required in RD-mediated apoptosis and that caspase-independent mechanisms were involved in RD-mediated cell death. Except for apoptosis, RD-induced autophagy occurred as evidenced by the accumulation of microtubule-associated protein-1 light chain-3B-II, formation of AVOs, punctate dots, and increased autophagic flux. Pharmacological blockade of autophagy activation markedly attenuated RD-mediated cell death. RD-induced cell death was significantly restored by the combination of autophagy and caspase inhibitors in osteosarcoma cells. Overall, our study revealed RD-induced caspase-dependent apoptosis and autophagy in cancer cells, as well as highlighted the importance of continued investigation on the use of RD as a potential anticancer candidate.

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Retigeric acid B (RB) has been reported to exhibit its anti-tumor activity in vitro and in vivo. Here, we found that RB significantly inhibited activity of topoisomerase IIα (Topo IIα), leading to remarkable DNA damage in prostate cancer (PCa) cells as evidenced by a strong induction of γH2AX and DNA fragmentation. Activation of ATM and ATR sequentially led to induction of phospho-Chk1/2 and phospho-Cdc25 in response to RB. Blockade of ATM/ATR signaling resulted in the attenuation of RB-induced γH2AX, and partially rescued RB-mediated cell death. RB treatment also resulted in inactivation of DNA repair proteins such as phospho-BRCA1, impairment of HR, and NHEJ repair as indicated by DNA end-joining assays. Meanwhile, a stress-responsive gene activating transcription factor 3 (ATF3) was noted for its predominant expression in response to RB-induced DNA damage. Knockdown of ATF3 inhibited the RB-induced expression changes of cell cycle- and apoptosis-related genes such as DR5, DDIT4, CDC25A, GADD45A, and partially blocked RB-mediated inhibition on cell proliferation and induction of apoptosis, suggesting the crucial involvement of ATF3 in this event. Microarray data displayed that RB caused changes of genes required for damaged-DNA binding and repair, as well as ATF3 and its target genes. Our data firstly demonstrated that RB was a novel DNA Topo II inhibitor and triggered cell death by inducing DNA damage and stress-response, suggesting a promising anticancer agent.

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Paclitaxel has been demonstrated to be an effective mitotic inhibitor and apoptosis inducer to treat aggressive malignancies. In this paper, we have provided a line of evidence that promotion of apoptotic cell death by paclitaxel was accompanied with induction of autophagy in A549 cells. Paclitaxel treatment could lead to the formation of acidic vesicular organelles (AVOs), the induction of Atg5, Beclin 1 and microtubule-associated protein 1 light chain 3 (LC3) expressions, and the increase of punctate fluorescent signals in A549 cells pre-transfected with green fluorescent protein (GFP)-tagged LC3. Interestingly, paclitaxel-mediated apoptotic cell death was further potentiated by pretreatment with autophagy inhibitor 3-methyladenine (3-MA) or small interfering RNA against the autophagic gene beclin1. These findings suggest that paclitaxel-elicited autophagic response plays a protective role that impedes the eventual cell death, and inhibition of autophagy could be an adjunctive strategy for enhancing chemotherapeutic effect of paclitaxel as an antitumor agent.

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