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91.
92.
We examined the emergence and sequential changes in type I, II, and VI collagen production in an experimental rabbit model of disc degeneration. Type I collagen was minimally present initially and did not change over 24 weeks. Type I collagen seemed to have no effect on the degenerative process in this model. Staining for type II collagen was positive circumferentially in chondrocytelike cells and was mild in the early phase of disc degeneration, when the chondrocytelike cells began to appear in the inner layers of the annulus fibrosus. The stain became stronger during the middle phase when the chondrocytelike cells arranged themselves in cluster. Compared with type II collagen, the staining for type VI collagen was relatively strong early in the degenerative process. These findings led us to speculate that these chondrocytelike cells play an active role in the degenerative process. The reinsertion of nucleus pulposus cells cocultured with annulus fibrosus delayed disc degeneration and the emergence of chondrocytelike cells. Considering that the emergence of chondrocytelike cells which produce type II and type VI collagen is delayed in discs with the injection of cocultured nucleus pulposus cells by annulus fibrosus cells, we conclude that chondrocytelike cells that produce type VI collagen also seems to accelerate degeneration. Type VI collagen is produced at an earlier phase than type II collagen and may be both active agent and a marker for disc degeneration.  相似文献   
93.
In the present study, an attempt was made to study the feasibility of nanoparticulate adsorbents in the presence of an absorption enhancer, as a drug delivery tool for the administration of erythropoietin (EPO) to the small intestine. Liquid filled nano- and micro-particles (LFNPS/LFMPS) were prepared using solid adsorbents such as porous silicon dioxide (Sylysia 550), carbon nanotubes (CNTs), carbon nanohorns, fullerene, charcoal and bamboo charcoal. Surfactants such as a saturated polyglycolysed C8-C18 glyceride (Gelucire 44/14), PEG-8 capryl/caprylic acid glycerides (Labrasol) and polyoxyethylene hydrogenated castor oil derivative (HCO-60) were used as an absorption enhancer at 50mg/kg along with casein/lactoferrin as enzyme inhibitors. The absorption of EPO was studied by measuring serum EPO levels by an ELISA method after small intestinal administration of EPO-LFNPS preparation to rats at the EPO dose level of 100 IU/kg. Among the adsorbents studied, CNTs showed the highest serum EPO level of 62.7 +/- 11.6 mIU/ml. In addition, with the use of casein, EPO absorption was improved, C(max) 143.1 +/- 15.2 mIU/ml. Labrasol showed the highest absorption enhancing effect after intra-jejunum administration than Gelucire 44/14 and HCO-60, 25.6 +/- 3.2 and 22.2 +/- 3.6 mIU/ml, respectively. Jejunum was found to be the best absorption site for the absorption of EPO from LFNPS. The use of CNTs as LFNPS, improved the bioavailability of EPO to 11.5% following intra-small intestinal administration.  相似文献   
94.
检测白血病细胞系KOCL-33EPO受体(EPOR)的表达并阐明EPOR介导的增殖信号的转导途径,用生物素酰基化EPO和流式细胞仪检测EPOR的表达,用免疫沉淀法和Western印迹法检测EPOR,SHC和PLC-γ的酪氨酸磷酸化,结果发现KOCL-33细胞可有EPOR的表达,且EPO可引起其增殖,EPO刺激后1分钟,EPOR形成同源二聚体,出现酪氨酸磷酸化;EPO刺激后1分钟,SHC和PLC-γ出现免疫共沉淀和酪氨酸磷酸化增强,上述结果说明在EPOR介导的KOCL-33细胞增殖信号的传导中,EPOR形成同源二聚体、出现酪氨酸磷酸化,且SHC和PLC-γ两结合在一起协同发挥作用。  相似文献   
95.
目的 检测白血病细胞系红细胞生成素受体(EpoR)的表达并阐明EpoR介导的白血病细胞系KOCL-33增殖信号传导途径。方法 用生物系酰基化Epo及流式细胞仪检测白血 纱KOCL-33细胞中几种信号传导蛋白 酷氨酸磷酸化。结果 (1)除T淋巴细胞系外,其余细胞纱EpoR表达均为阳性,阳性率为18%~99%,均值52%。不同类型的细胞系EpoR阳性率的差异没有统计学意义。(2)9株细胞中7株细胞因受  相似文献   
96.

Ethnopharmacological relevance

Several Northern Hemisphere Drosera species have been used in the therapy of respiratory tract infections as the traditional medicine Droserae Herba.

Aim of the study

To determine the anti-inflammatory effects of Drosera species and to investigate a substitute material for Droserae Herba, we examined the effect of extracts of Drosera rotundifolia, Drosera tokaiensis and Drosera spatulata on activated T cell membrane (aTc-m)-induced inflammatory gene expression in HMC-1 human mast cells.

Materials and methods

Drosera rotundifolia, Drosera spatulata and Drosera tokaiensis were collected in Japan. Herbs were extracted with 80% EtOH, and subsequently applied to OASIS HLB column. HMC-1 cells were treated with each Drosera column-adsorbed fraction for 15 min, and subsequently added to aTc-m and incubated for 16 h. Inflammatory gene and protein expressions were determined by DNA microarray, RT-PCR and Western blotting.

Results

Drosera rotundifolia and Drosera tokaiensis fractions, but not the Drosera spatulata fraction, suppressed inflammatory gene expression induced by aTc-m in HMC-1 cells.

Conclusions

Drosera rotundifolia and Drosera tokaiensis suppressed activation of HMC-1 cells induced by aTc-m. Since the Drosera tokaiensis fraction was more effective than the traditionally used Drosera rotundifolia, Drosera tokaiensis is a likely substitute as a source of Droserae Herba.  相似文献   
97.
98.
We report a case of synovial sarcoma in the neck that was initially considered to be a benign soft-tissue tumour. The mass appeared to originate in the perivertebral space, extending to the spinal canal via the C3/4 and C4/5 neural foramina. The mass also encased the right vertebral artery and this suggested a malignant soft-tissue tumour.  相似文献   
99.
Purpose. Vascular endothelial growth factor C (VEGF-C) is known to be associated with the development of the lymphatic vessel system. Recently, VEGF-C is thought to be correlated with lymph node metastasis in some malignant tumors. In this study, we investigated the correlation between VEGF-C expression and lymph node metastasis in early carcinoma of the colon and rectum. Methods. Two hundred and twenty-one endoscopically biopsied specimens from patients with T1 colorectal carcinoma prior to operation were investigated by an immunohistochemical study. Results. VEGF-C expression was more frequently observed in the tumors with nodal metastasis than in those without metastasis. Moreover, a multivariate analysis indicated that VEGF-C expression is an independent predictor of lymph node metastasis. Conclusion. VEGF-C staining using endoscopically biopsied specimens prior to operation could be of use in the prediction of lymph node metastasis and in preoperative selection of treatment in patients with T1 colorectal carcinoma.  相似文献   
100.
Background Despite the recent wide availability of ultrasonography and fine-needle aspiration biopsy, endocrine surgeons often encounter incidental papillary carcinoma (IPC), that is a papillary carcinoma that had gone undetected by preoperative imaging studies but was identified by pathological examination of surgical specimens resected for benign thyroid diseases. Methods The present study was developed to investigate the prognoses of 317 patients who underwent surgery for benign diseases involving IPC in comparison with the prognoses of 1,674 patients with clinically apparent papillary carcinoma detected preoperatively and diagnosed. Results None of the patients underwent further surgery such as completion total thyroidectomy and node dissection immediately after the diagnosis of IPC. To date, 7 patients (2.2%) have had recurrences; 6 of those were locoregional recurrences and one was a bone metastasis. None of the patients have died of thyroid carcinoma. The disease-free survival of IPC patients was significantly better than that of clinically apparent papillary carcinoma patients and was similar to that of the subset of patients with papillary microcarcinoma without clinically apparent metastasis. Conclusions Because IPC is associated with good prognosis, further surgery, such as completion total thyroidectomy or lymph node dissection immediately after the diagnosis of IPC is not necessary.  相似文献   
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