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991.

Background and purpose

KRAS and BRAF are mutated in 35% and 10% of colorectal cancers, respectively. However, data specifically for locally advanced rectal cancers are scarce, and the frequency of KRAS mutations in codons 61 and 146 remains to be established.

Materials and methods

DNA was isolated from pre-therapeutic biopsies of 94 patients who were treated within two phase-III clinical trials receiving preoperative chemoradiotherapy. Mutation status of KRAS exons 1-3 and BRAF exon 15 was established using the ABI PRISM Big Dye Sequencing Kit and subsequently correlated with clinical parameters.

Results

Overall, KRAS was mutated in 45 patients (48%). Twenty-nine mutations (64%) were located in codon 12, 10 mutations (22%) in codon 13, and 3 mutations (7%) in codons 61 and 146. No V600E BRAF mutation was detected. The presence of KRAS mutations was correlated neither with tumor response or lymph node status after preoperative chemoradiotherapy nor with overall survival or disease-free survival. When KRAS exon 1 mutations were separated based on the amino-acid exchange, we again failed to detect significant correlations (p = 0.052). However, G12V mutations appeared to be associated with higher rates of tumor regression than G13D mutations (p = 0.012).

Conclusion

We are the first to report the mutation status of KRAS and BRAF in pre-therapeutic biopsies from locally advanced rectal cancers. The high number of KRAS mutations in codons 61 and 146 emphasizes the importance to expand current mutation analyses, whereas BRAF mutations are not relevant for rectal carcinogenesis. Although the KRAS mutation status was not correlated with response, the subtle difference between G12V and G13D mutations warrants analysis of a larger patient population.  相似文献   
992.
We report herein the case of a 70-year-old man who was found to have a gastrointestinal stromal tumor (GIST) in the stomach following sigmoid colon resection. Preoperative gastroscopic and barium examinations revealed a submucosal tumor, measuring 10cm, on the upper part of the stomach. Using computed tomography (CT) images (i.e., computed tomographic volumetry) the doubling time of this tumor was calculated, accurately, as 3.3 months, which suggested a high growth rate and malignancy. A laparotomy and partial gastric resection were performed. Histologically, the tumor consisted of spindle-shaped cells with oval nuclei. In immunohistochemical studies, the tumor cells were positive with respect to c-kit, CD34, and vimentin, but negative with respect to smooth muscle actin and S-100 protein. There were 15–16 mitoses per 50 high-power fields (HPFs), and the Ki-67 antigen (MIB-1) index was 25.5% in the most active areas, which also indicated malignancy. The final pathological diagnosis of this tumor was malignant GIST. The patient was found to have hepatic metastasis 27 months after the surgery, and he subsequently received a hepatic subsegmentectomy. To our knowledge, there are very few reports concerning the growth rate of GISTs. Computed tomographic volumetry is useful for the follow-up of small or irregularly shaped gastric submucosal tumors, and for making decisions regarding surgical intervention.  相似文献   
993.
Ascites are commonly found in ovarian cancer patients with advanced disease and are rich in cellular components and growth-promoting factors. The purpose of this study was to assess the effect of malignant ascites on TRAIL-induced apoptosis. We demonstrate that malignant ascites obtained from women with advanced ovarian cancer protect tumor cells from TRAIL- and FasL-induced apoptosis but not against cisplatin-induced apoptosis. This antiapoptotic effect was consistently found among different malignant ascites while nonmalignant peritoneal fluids or conditioned medium from TRAIL-resistant cells failed to protect tumor cells against TRAIL killing. Malignant ascites strongly inhibits TRAIL-induced caspase-3 activation and PARP cleavage. Furthermore, ascites activate PI3K and its downstream target Akt and increases c-FLIP(S) protein levels without affecting ERK phosphorylation status. The antiapoptotic effect of malignant ascites is abrogated by the inhibition of PI3K with LY294002, by a specific inhibitor of Akt and by Akt siRNA. We further show that the pro-survival effect of ascites can be suppressed by down-regulation of c-FLIP(S). Our data indicate that malignant effusions protect against TRAIL-induced apoptosis by activating the PI3K/Akt pathway. These findings demonstrate that the tumor microenvironment may contribute to the resistance of ovarian cancer cells to death receptor-induced apoptosis.  相似文献   
994.
Objective: To investigate the effects and mechanisms of tumor suppressor gene PTEN on the induction of anoikis of human bladder transitional carcinoma cells BIU-87. Methods: BIU-87 cells were transfected with GFP plasmids containing wild-type PTEN or phosphatase inactivating mutant PTEN (C124A-PTEN) in vitro. The PTEN expression and the phosphorylation levels of focal adhesion kinase (FAK) and protein kinase B (PKB/Akt) were detected by Western blotting. Flow cytometry assay and laser scanning confocal microscopy were used to analyze apoptosis in adherent and non-adherent cells. Results: Compared with the control group; PTEN expression in the cells transfected with wild-type PTEN increased to 210%-260%, while the phosphorylation level of FAK and Akt decreased 59% ( P 〈 0.01) and 89% ( P 〈 0.01), respectively. And the anoikis percentage increased from 8,32 ± 0.57% to 37.62 ± 2.12%, In the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the anoikis percentage had obviously changed, although the PTEN expression enhanced remarkably in comparison with the control. Conclusion: Through its phosphatase activity, tumor suppressor gene PTEN can suppress the phosphorylation of FAK and Akt, and induce anoikis in human bladder transitional carcinoma cells BIU-87.  相似文献   
995.

Objective  

The aim of this study was to investigate the characteristics of gene changes from Barrett’s esophagus (BE) to esophageal adenocarcinoma by cDNA microarray.  相似文献   
996.

Objective

To observe the effect of applying tuina to exterior-interiorly connected meridians for post-stroke upper limb spasticity.

Methods

A total of 150 patients with post-stroke upper limb spasticity were randomly allocated into a treatment group (n=75) and a control group (n=75) by the random number table. Patients in the treatment group received tuina on exterior-interiorly connected meridians, whereas patients in the control group received standard rehabilitation therapy. The therapeutic efficacies in both groups were observed after 3 weeks of treatment.

Results

The total effective rate in the treatment group was 89.3%, versus 61.3% in the control group, showing a statistically significant difference (P<0.05). After the treatment, the muscle tones by the modified Ashworth scale (MAS) were significantly improved in both groups (both P<0.05); and the improvement of muscle tone was more significant in the treatment group than that in the control group (P<0.05).

Conclusion

Applying tuina to exterior-interiorly connected meridians can obtain an exact efficacy for post-stroke upper limb spasticity.
  相似文献   
997.
目的:研究不同处理方法对卵白蛋白(Ovum Albumin,OVA)变应性鼻炎小鼠模型腹腔肥大细胞脱颗粒的影响。方法:将60只雌性小鼠随机分为5组,每组12只,分别按不同方法处理后分离各组小鼠的腹腔肥大细胞,中性红染色后计算腹腔肥大细胞脱颗粒率。结果:正常对照组、OVA变应性鼻炎组、穴位敷贴组、激素对照组、磷酸盐缓冲液(Phosphate Buffer Saline,PBS)阴性对照组小鼠腹腔肥大细胞脱颗粒率分别为(15±6)%、(53±11)%、(37±13)%、(31±15)%、(47±14)%。OVA变应性鼻炎小鼠的腹腔肥大细胞有明显的脱颗粒现象:与OVA变应性鼻炎小鼠相比,穴位敷贴组及激素对照组小鼠的腹腔肥大细胞脱颗粒现象显著减轻;PBS对照组小鼠的腹腔肥大细胞脱颗粒现象没有明显变化。结论:推测穴位敷贴抗过敏机制为稳定肥大细胞膜,抑制肥大细胞脱颗粒,减少致炎介质产生。  相似文献   
998.
用梅花针叩刺斑秃区,后用艾条在患处温灸,治疗斑秃患者53例,并以口服薄芝片为对照治疗54例.3个疗程后前者总有效率为96.2%,后者为70.4%,两组疗效差异有统计意义.  相似文献   
999.

Objective

To observe the clinical effects of tuina plus Western medication for functional dyspepsia (FD) due to liver qi stagnation and spleen deficiency.

Methods

total of 72 patients in conformity with the inclusion criteria of FD were randomly divided into an observation group and a control group based upon the random number table, 36 cases in each group. The control group was treated with mosapride citrate dispersible tablets, and the observation group was treated with the same tablets plus tuina. Before the treatment and 4 weeks after the treatment, the clinical symptoms, quality of life (QOL) and depression severity were observed by the scale, and were followed up two months later after the treatment for assessment of the clinical effects.

Results

After the treatment and at the follow-up, the symptom scores of FD and the sores of Hamilton depression rating scale (HAMD) in both groups decreased, and the scores in Chinese version of quality of life questionnaire for functional digestive disorders (Chin-FDDQL) increased, with statistically significant differences in comparison with the same group before the treatment (all P<0.05). In comparison between the two groups at the same time point after the treatment, the scores of FD symptoms, HAMD and Chin-FDDQL were improved better in the observation group than those in the control group, with statistically significant differences (all P<0.05). The total effective rates at the follow-up were 91.7% in the observation group and 75.0% in the control group, without statistical difference between the two groups (P>0.05). The rate of clinical cure and remarkable effect was 66.7% in the observation group, higher than 41.7% in the control group, it is higher in the observation group than that in the control group, with a statistically significant difference between the two groups (P<0.05).

Conclusion

Tuina plus Western medication is precise in the therapeutic effects for FD due to liver qi stagnation and spleen deficiency and can effectively relieve clinical symptoms, elevate the QOL and alleviate depression severity of the patients. Moreover, it’s better than the treatment by Western medication alone in the long-term therapeutic effects.
  相似文献   
1000.
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