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91.
In the antimycobacterial susceptibility test for INH using the egg-based Ogawa media, 3 concentrations (0.1, 1, or 5 micrograms/ml) of INH were used, and 1 microgram/ml was used as a critical concentration for INH resistance. However, it was controversial whether INH 0.1 microgram/ml resistant M. tuberculosis was clinically significant or not. We investigated the MIC values of INH 0.1 microgram/ml resistant strains by using BrothMIC MTB-1 method, and 115 strains of M. tuberculosis confirmed by DNA-prove test were used. The distribution of MIC values of 115 strains determined by Ogawa INH susceptibility test was shown in figure. By BrothMIC MTB-1 method, they were classified into 3 groups; susceptible, low resistant and high resistant groups. The mean MIC value of INH 0.1 microgram/ml resistant M. tuberculosis was estimated to be 4.53 micrograms/ml with its 95% confidence interval 3.21-5.85 micrograms/ml, and they were determined as "resistant" in BrothMIC MTB-1 method. These results supported the idea that patients with INH 0.1 microgram/ml resistant M. tuberculosis strains should be regarded as clinically "resistant".  相似文献   
92.
Platelet-derived growth factor (PDGF) plays an important role in the pathogenic course of atherosclerosis, pulmonary fibrosis, and glomerulonephritis, and increased activity of the PDGF signaling pathway has been implicated as a contributing factor in the progression of the diseases. Taurine may be a prophylactic amino acid for atherosclerosis not only by decreasing plasma cholesterol level, but also by inhibiting the cell proliferation-signaling pathway. To elucidate how taurine affects the signaling pathway, we investigated the effect of taurine on the expression of immediate-early genes and activation of mitogen-activated protein kinases (MAPKs) in NIH/3T3 cells as standard mesenchymal cells. Taurine inhibited PDGF-BB-induced c-fos and c-jun mRNA expressions dose-dependently, although structural analogues of taurine did not. Taurine decreased the PDGF-induced p44/p42 ERK (extracellular signal-regulated kinase) phosphorylation state dose-dependently, although no phosphorylation was observed on JNK/SAPK (c-Jun N-terminal kinase/stress-activated protein kinase) and p38 MAPK. Further, PDGF-BB-induced tyrosine phosphorylation of the PDGF-beta receptor was not influenced by treatment with taurine, indicating that taurine never affects ligand-receptor interaction, and may act downstream of the PDGF receptor. Thus, the inhibitory mechanism of taurine on PDGF-induced c-fos and c-jun mRNA expressions may depend on the p44/p42 ERK pathway, but not on PDGF-beta receptor tyrosine phosphorylation, JNK/SAPK or p38 MAPK pathway. These results suggest that taurine may suppress the cell proliferation-signaling pathway through the inhibition of ERK activity and immediate-early gene expression.  相似文献   
93.
Postcontrast CT scanning using multislice CT was performed for 20 patients with gastric cancer. Three-dimensional (3D) CT angiography of the arterial and venous phases was reconstructed using the volume-rendering technique and then fused. 3D-CT angiography showed the arteries and veins around the stomach, and multiphase fusion imaging was able to demonstrate clearly and three-dimensionally the gastric vascular anatomy. In conclusion, the multiphase fusion image was considered to be useful in the preoperative simulation of laparoscopic gastric cancer surgery.  相似文献   
94.
PURPOSE: To quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. METHODS: A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. RESULTS: A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6 +/- 132.7 and 41.0 +/- 27.0 ml/min/ 100 g, arterial blood volume was 19.4 +/- 14.6 and 4.8 +/- 4.2 ml/100 g, and arterial mean transit time was 8.9 +/- 4.2 and 10.2 +/- 5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. CONCLUSION: This technique could be used to quantify pure hepatic arterial blood perfusion.  相似文献   
95.
The immunocompetence and nutritional state of patients with advanced or recurrent gastric cancer is low, making it important to conduct chemotherapy while at the same time improving or maintaining their immunocompetence and nutritional state. To reduce the side effects but not the antitumor effect of TS-1, a 2-week regime of TS-1, and 1-week drug-free interval, in combination with the immunotherapeutic agent lentinan (LNT) was started in 5 patients with advanced or recurrent gastric cancer. Toxicity, efficacy, immunocompetence and nutritional state were investigated preliminarily to examine whether or not usefulness of lentinan could be evaluated. The IAP tended to decrease. TS-1 and lentinan combination immunochemotherapy was able to be carried out safely in patients with advanced recurrent gastric cancer. In order to examine the usefulness of combined LNT, it is thought to be necessary to perform a randomized trial using toxicity and not only efficacy but QOL and immunological and nutritional parameters as indicators.  相似文献   
96.
BACKGROUND: Survivin, a novel inhibitor of apoptosis, is undetectable in normal adult tissues but becomes notably expressed in the most common human cancers, and is recognized as a potential target in anticancer therapy. METHODS: In this study we evaluated a survivin antisense expressing replication-incompetent adenoviral vector under the control of the cytomegalovirus promoter (pAd.CMV-SAS) for cytoreductive effects in human HT-29 colon cancer cells in vitro and in vivo. RESULTS: Infection of tumor cells with pAd.CMV-SAS caused down-regulation of survivin expression and the potential for spontaneous apoptosis in tumor cells. In contrast, pAd.CMV-SAS did not affect cell viability of normal human cells including fibroblasts. In addition, infection of tumor cells with pAd.CMV-SAS resulted in an increase of the G0/G1 phase population in the cell cycle, and increased their sensitivity to chemotherapeutic drugs in vitro. The efficacies of pAd.CMV-SAS were inversely correlated with survivin expression level. In nude mice, pAd.CMV-SAS suppressed tumor formation, as well as decreased the tumor volumes to approximately 30% of the control tumors. Furthermore, it was confirmed that the anti-tumor efficacy of pAd.CMV-SAS was also enhanced in combination with chemotherapeutic drugs in vivo. CONCLUSIONS: These findings suggest that targeting of survivin using adenoviral antisense vectors may have a potential role in the selective therapy of colon cancer.  相似文献   
97.
Interleukin-21 (IL-21) is a novel cytokine that can induce proliferation of activated T cells and maturation of natural killer (NK) cells. We therefore examined whether expression of the IL-21 gene in tumor cells could generate antitumor responses. Murine colon carcinoma Colon 26 cells that were transduced with the mouse IL-21 gene (Colon 26/IL-21) were rejected in syngeneic mice and the mice subsequently acquired protective immunity. The growth of Colon 26/IL-21 tumors developed in nude mice was retarded compared with that of parent tumors, and this growth suppression was not observed in nude mice that were treated with anti-asialo GM(1) antibody. Spleen cells from the mice that had rejected Colon 26/IL-21 cells showed cytotoxic activity to Colon 26 but not to irrelevant tumor cells, and produced larger amounts of interferon-gamma upon stimulation with irradiated Colon 26 cells. Spleen cells from Colon 26/IL-21-tumor- but not parent-tumor-bearing mice had lytic activity to YAC-1 cells. These data suggest that expression of IL-21 in tumors induces T- and NK-cell-dependent antitumor effects.  相似文献   
98.
The Wnt/beta-catenin signaling pathway is critical for normal mammalian development, the specification of epidermal cells and neoplastic transformation of intestinal epithelium. However, precise molecular information regarding cell-specific responses to beta-catenin signaling has been limited. This question was addressed using a mouse model in which exon 3 of the beta-catenin gene was deleted in several cell types with loxP-mediated recombination utilizing a Cre transgene under control of the mouse mammary tumor virus-long terminal repeat (MMTV-LTR). The stabilization of beta-catenin in prostate epithelium resulted in hyperplasias and extensive transdifferentiation into epidermal-like structures, which expressed keratins 1 and 6, filaggrin, loricrin and involucrin. The cell-specific loss of NKCC1 protein and reduced nuclear Stat5a is further suggestive of a loss of prostate epithelial characteristics. In addition to the prostate, hyperplasias and squamous metaplasias were detected in epithelia of the epididymis, vas deferens, coagulating gland, preputial gland and salivary gland. However, and in contrast to a recent study, no lesions reminiscent of high-grade prostate intraepithelial neoplasia were detected. Since beta-catenin was activated in several cell types and impinged upon the viability of these mice, it was not possible to evaluate the cumulative effect over more than 3 months. To assess long-term consequences of beta-catenin activation, mutant and control prostate tissues were transplanted into the mammary fat pads of wild-type males. Notably, squamous metaplasias, intra-acinous hyperplasia and possible neoplastic transformation were observed after a total of 18 weeks of beta-catenin stimulation. This suggests that the transdifferentiation into squamous metaplasias is an early response of endoderm-derived cells to beta-catenin, and that the development of intra-acinous hyperplasias or neoplastic foci is a later event.  相似文献   
99.
Although the health care costs and the number of disability cases across all medical illnesses have increased, disability management programs implementing stress management interventions have been found to improve physical and mental health, reduce costs to employers, and facilitate the reintegration of injured individuals into the work environment. Stress management programs limit the impact and chronicity of disabilities and can be used to reduce and control the cost of disability in the workplace. Providing the most efficacious behavioral interventions thereby allows employers, employees and health professionals to work cooperatively to achieve optimum health and cost effectiveness. This review presents a variety of group and individual interventions, which have been utilized to aid disabled employees in coping with work-related injuries and medical illness. The implementation of stress management interventions in the workplace is described in detail, with special emphasis on the use of cognitive behavioral stress management. Finally, this review outlines a team approach to the application of a workplace stress management intervention aimed at reducing the overall impact of disability.  相似文献   
100.

Background

The response rate of advanced or recurrent gastric cancer to S-1 (TS-1®) is 46.5%, which is higher than the response rate of this type of cancer to any other anticancer agent. However, the incidence of adverse reactions to this drug has also been reported to be as high as 83.2%. According to a postmarketing survey, adverse reactions to this drug begin to appear 2–3 weeks after the start of drug administration. With these findings in mind, we recently devised a new dosing regimen for the drug, by which the drug is administered for 2-week periods separated by 1-week drug-free intervals (the 2-week regimen). The aim of this retrospective study was to evaluate the efficacy and feasibility of the 2-week regimen in comparison with a 4-week dosing regimen with a 2-week interval between sessions (the 4-week regimen) as the historical control.

Methods

The subjects were 27 patients with advanced or recurrent gastric cancer who received S-1 therapy at our center between September 1999 and November 2001. Of these patients, 14 who received the 4-week regimen before January 2001 served as historical controls, and the results in these patients were compared with those of the remaining 13 patients, who received the 2-week regimen after February 2001. Patient backgrounds, adverse reactions, compliance, and efficacy were investigated retrospectively.

Results

The incidence of adverse reactions tended to be lower in the 2-week-regimen group (77%) than in the 4-week-regimen group (93%). The percentage of patients who received the drug for 6 months in complete compliance with the dosing schedule, as calculated by the Kaplan-Meier method, was 85% in the 2-week-regimen group and 40% in the 4-week-regimen group. The response rate to the drug was 23% in the 2-week-regimen group and 21% in the 4-week-regimen group.

Conclusion

These results suggest that this 2-week regimen may mitigate adverse reactions and prolong the medication period.
  相似文献   
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