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1.
Neoadjuvant cisplatin-based chemotherapy (NAC; 70 mg/m2) is standard of care for muscle-invasive bladder carcinoma (MIBC). Many patients (pts) cannot receive cisplatin because of renal impairment, and administration of cisplatin 35 mg/m2 on day 1 + 8 or 1 + 2 (i.e., split schedule) is a commonly used alternative. In this retrospective analysis, we compared complete (pT0) and partial (<pT2) pathologic response rates between split schedule (SS) and conventional schedule (CS) pts, after 1:1 matching on chemotherapy regimen, number of cycles, tumor histology, and clinical stage. Eighty matched pts were identified. pT0 rates were 17.5% (95% confidence interval [CI], 7%–33%) and 32.5% (95% CI, 19%–49%) in SS and CS cisplatin pts, respectively (p = .21), corresponding to an odds ratio for pT0 of 0.45 (95% CI, 0.16–1.31) with SS cisplatin. Split schedule cisplatin was associated with numerically but not statistically significant lower pathologic response rates relative to full dose.  相似文献   
2.

Background

The response to first-line, platinum-based treatment of muscle-invasive bladder cancer has not improved in 3 decades.

Objective

To identify genes that influence cisplatin resistance in bladder cancer.

Design, setting, and participants

We performed a whole-genome CRISPR screen in a bladder cancer cell line to identify genes that mediate resistance to cisplatin.

Outcome measurements and statistical analysis

Targeted validation was performed in two bladder cancer cell lines. The top gene candidate was validated in a publicly available bladder cancer dataset.

Results and limitations

From the CRISPR screen, we identified MSH2 as the most significantly enriched gene and mismatch repair as the most significantly enriched pathway that promoted resistance to cisplatin. Bladder cancer cells with knockdown of MSH2 showed a reduction in cisplatin-mediated apoptosis. MSH2 loss did not impact the sensitivity to other chemotherapies, including the cisplatin analog oxaliplatin. Bladder tumors with low MSH2 protein levels, quantified using reverse-phase protein array, showed poorer survival when treated with cisplatin- or carboplatin-based therapy; these results require future validation using immunohistochemistry. Additionally, results are retrospective from patients with primarily high-grade tumors; thus, validation in a controlled clinical trial is needed.

Conclusions

We generated in vitro evidence that bladder cancer cell lines depleted of MSH2 are more resistant to cisplatin. We additionally found an association between low MSH2 in bladder tumors and poorer patient survival when treated with platinum-based chemotherapy. If successfully validated prospectively, MSH2 protein level could assist in the selection of patients for chemotherapy.

Patient summary

We report the first evidence that MSH2 protein level may contribute to chemotherapy resistance observed in muscle-invasive bladder cancer. MSH2 has potential as a biomarker predictive of response to platinum-based therapy.  相似文献   
3.
Gastric cancer, one of the most common disease, has become a major public health problem worldwide. Cisplatin (DDP) has been a widely used drug for the treatment of cancer, also usually applied in gastric cancer in clinic. However, the side effects including toxicity and drug-resistance restricted the usage of DDP in clinic, so we prepared a DDP-complexed hydrogel (DDP-Gel) and investigated its efficacy in gastric cancer. For in vivo studies, MKN45-Luc cells were injected into BLAB/C node mice subcutaneously to establish gastric cancer with orthotopically grown tumors. Mice bearing tumors were treated with normal saline, DDP and DDP-Gel. Body weight and survival condition were observed and recorded. The treatment efficacy in vivo was detected by luciferase imaging and histological evaluation was performed by H&E staining of different organs. Additionally, normal ICR mice were treated with different doses of DDP/DDP-Gel to calculate their LD50 in vivo. The results showed that DDP-Gel prolonged survival time and ameliorated body weight changes of mice bearing tumors. DDP-Gel exhibited higher efficacy to inhibit tumor growth and metastasis, compared to DDP. Besides, LD50 of DDP-Gel was 166.0?mg/kg, 13.2 folds higher than DDP. As a conclusion, DDP-Gel showed a more effective and safer function than DDP in gastric cancer, which indicating that DDP-Gel might be a novel strategy for gastric cancer therapy.  相似文献   
4.
Cisplatin is an effective anticancer used widely in treatment of solid and germ cell tumors, however, the immense toxicity on healthy tissues discourages cisplatin use in prolonged treatment protocols. Testicular toxicity is amongst its undesired adverse effects. Nilotinib is a second generation multityrosine kinase inhibitor which is used as an anticancer agent with anti-inflammatory and antioxidant activities. In the present study, a single dose of cisplatin (7 mg/kg, I.P) to rats induced a significant testicular injury. Daily administration of nilotinib (20 mg/kg, orally) 24 h post cisplatin injection for 10 days ameliorated testicular damage. Nilotinib significantly increased serum testosterone and sperm concentration outside frame of oligospermia with simultaneous full recovery of sperm viability. Nevertheless, biomarkers of apoptosis such as JNKs and Caspase -3, were significantly reduced. Moreover, improved antioxidant status of the testes was inferred by significant elevation of GSR, SOD and TAC alongside with reduction in lipid peroxidation biomarkers; MDA and 4-HNE. Flow Cytometry analysis of the cell cycle confirmed a significant increase in the percentage of testicular cells present in G2/M phase and a significant decrease in the percentage of apoptotic testicular cells after nilotinib administration. Histopathologically, nilotinib preserved testicular architecture showing significant numbers of sperm and spermatids within lumens of seminiferous tubule. Furthermore, nilotinib enhanced testicular expression of Ki67 significantly, providing evidence of testicular regeneration. In conclusion, nilotinib refinement of cisplatin induced testicular toxicity is attributed to enhancing antioxidant capabilities, decreasing apoptotic signals and restoring regenerative capacity of testes suggesting nilotinib to be used in conjunction with cisplatin in treatment protocols to avoid cisplatin induced long term testicular toxicity.  相似文献   
5.
6.
BackgroundA unique time in which to effectively treat an intraabdominal malignancy is the time at which the surgeon attempts complete removal of the malignant process. Although surgery is effective for visible disease, micrometastases or multiple small cancer nodules are not amenable to resection. Alternative interventions to deal with residual disease disseminated on peritoneal surfaces are needed.Materials and methodsCytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can be combined with early postoperative intraperitoneal chemotherapy (EPIC) in order to maximally treat gross disease within the abdomen and pelvis and also the minimal residual disease that exists in many patients after resection. The third component of this treatment for ovarian malignancy was EPIC paclitaxel in this study. The clinical features, pharmacologic assessments, and survival were determined in ovarian cancer patients in whom EPIC was added to the perioperative treatment plan.ResultsPatients with high grade serous ovarian cancer underwent CRS, HIPEC with cisplatin/doxorubicin, and EPIC paclitaxel. These treatments combined as a single intervention were studied in 10 patients. The median number of peritonectomy procedures was 1, the median number of visceral resections was 5, and the median time required in the operating room was 8 h. Two patients had a class 3 adverse event. The median survival of patients was 50 months. Pharmacokinetic analysis of the intraperitoneal paclitaxel showed 252 ± 153 times exposure of peritoneal surfaces as compared to intravenous exposure when the drug was instilled into the peritoneal space.ConclusionsEPIC paclitaxel was successfully combined with CRS and HIPEC in 10 patients with ovarian cancer. The treatment was tolerated approximately the same as other major cytoreductive surgical procedures for ovarian cancer or other malignancies. Survival of these ovarian cancer patients seemed unusually prolonged as compared to other patients with stage 3b or recurrent disease. In this pilot study CRS, HIPEC and EPIC were safe and effective.  相似文献   
7.
以铂类药物为基础的化疗成为晚期头颈部鳞癌(head and neck squamous cell carcinoma,HNSCC)综合治疗中不可缺少的部分。化疗可与放疗同步用于局部晚期HNSCC的根治性治疗,或用于具有高危因素的HNSCC术后辅助治疗,也可用于诱导化疗(新辅助化疗)或者放疗后的辅助化疗。同期放化疗在局部晚期HNSCC的治疗中尤其重要。几种常用的铂类药物在HNSCC的治疗中各有优势。本文简述铂类药物的药理作用及机制,比较铂类药物在HNSCC的疗效与毒性,并分析不同给药方式(单药或多药联合,每周或每3周)与给药剂量所带来的疗效与毒性差异,希望能对医师合理使用铂类药物治疗HNSCC有所裨益。  相似文献   
8.

Background

Treatment of advanced anal squamous cell cancer (SCC) is usually with the combination of cisplatin and 5-fluorouracil, which is associated with heterogeneous responses across patients and significant toxicity. We examined the safety and efficacy of a modified schedule, FOLFCIS (leucovorin, fluorouracil, and cisplatin), and performed an integrated clinical and genomic analysis of anal SCC.

Patients and Methods

We reviewed all patients with advanced anal SCC receiving first-line FOLFCIS chemotherapy – essentially a FOLFOX (leucovorin, fluorouracil, and oxaliplatin) schedule with cisplatin substituted for oxaliplatin – in our institution between 2007 and 2017, and performed deep sequencing to identify genomic markers of response and key genomic drivers.

Results

Fifty-three patients with advanced anal SCC (48 metastatic; 5 unresectable, locally advanced) received first-line FOLFCIS during this period; all were platinum-naive. The response rate was 48% (95% confidence interval [CI], 32.6%-63%). With a median follow-up of 41.6 months, progression-free survival and overall survival were 7.1 months (95% CI, 4.4-8.6 months) and 22.1 months (95% CI, 16.9-28.1 months), respectively. Among all patients with advanced anal SCC that underwent sequencing during the study period, the most frequent genomic alterations consisted of chromosome 3q amplification (51%) and mutations in PIK3CA (29%) and KMT2D (22%). No genomic alteration correlated with response to platinum-containing treatment. Although there were few cases, patients with human papillomavirus-negative anal SCC did not appear to benefit from FOLFCIS, and all harbored distinct genomic profiles with TP53, TERT promoter, and CDKN2A mutations.

Conclusions

FOLFCIS appears effective and safe as first-line chemotherapy in patients with advanced anal SCC and represents an alternative treatment option for these patients.  相似文献   
9.
10.
Cis-diamminedichloridoplatinum(II)(CDDP)-based combination chemotherapy is frequently used in gastrointestinal cancer. The synergistic mechanism of all-trans retinoic acid (ATRA), cisplatin (CDDP) and 5-fluorouracil (5-FU) in combination remains unclear. Despite their potent antitumor properties, resistance to CDDP and 5-FU develops frequently in tumors. To clarify this mechanism, we determined the sensitivity to each drug and their combination in two gastrointestinal cancer stem cells (CSCs) subpopulation.Here, we report the identification and separation of CD44+ cells from human gastric carcinoma (AGS) and human esophageal squamous cell carcinoma (KYSE-30) cancer cell lines by magnetic activated cell sorting (MACS). We allowed the CD44± cells to grow 6 days at a subtoxic concentration of ATRA and then treated with different concentration of CDDP and 5-FU for 24 h. The cytotoxicity was examined by cell proliferation MTT assay. Additionally, AO/EB staining was used for detection of apoptotic cells. In order to determine whether the growth inhibition was also associated with changes in cell cycle distribution, cell cycle analysis was performed using flow cytometry.Low concentration of ATRA (1 μM, 6days) followed by 5-FU and CDDP was found to be more effective than either drugs alone, thus resulting in synergistic cytotoxicity in Kyse-30 and AGSCD44± cells. Furthermore, there was an indication that the combination of ATRA with 5FU and CDDP caused an increase in cell cycle arrest in G2/M and G0/G1.We conclude that low concentration of ATRA enhances the cytotoxicity of CDDP and 5FU by facilitating apoptosis and cell cycle arrest in gastrointestinal CSCs and provide a rational basis for the design of novel, well-tolerated CDDP- and 5FU-based chemotherapy in human gastrointestinal carcinoma.  相似文献   
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