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61.
Single nucleotide polymorphisms (SNPs) of adhesion and signaling genes may influence the etiopathogenesis of multiple myeloma (MM). CD38 molecule and its ligand CD31 are expressed and interact in malignant plasma cells and MM microenvironment. In this study we evaluated allele frequencies and distribution of two potentially functional CD38 SNPs, intronic rs6449182 (184C>G) and missense rs1800561 (418C>T, Arg140Trp) in 175 Caucasian patients with MM and 207 healthy blood donors. The carriers of variant G allele of the rs6449182 SNPs were found to have significantly elevated risk of MM as compared to non-carriers; odds ratio = 5.69 (95% confidence interval = 3.7–8.7), p < 0.0001. In contrast, rs1800561 SNP minor T allele was detected at very low and comparable frequencies in patients and controls groups. In conclusion, our data suggest that inherited genetic variation in CD38 gene may impact on the risk of MM development.  相似文献   
62.
Background. Percutaneous vertebroplasty involves the injection of acrylic surgical cement into the vertebral body. The basic principles of vertebroplasty and the authors' own clinical experiences are described. Material and methods. Between November 1999 and January 2005 the authors performed percutaneous vertebroplasty on 75 patients: 45 with osteoporotic compression fractures, 15 with angiomas of the vertebral bodies, and 12 patients with spinal neoplasms. There were also 3 patients with coexisting spinal angiomas and osteoporotic compression fractures. All these patients were treated under local anesthesia. Cement injections were realized by the transpedicular approach under fluoroscopic guidance; in certain cases a CT-guided approach was used. The clinical outcome was assessed based on follow-up examinations, the Oswestry questionnaire, and the Visual Analog Pain Scale. Plain x-rays or CT scans were made for purposes of radiological evaluation. Results. Follow-up examinations revealed pain relief or significant reduction of pain in 89% of the patients. In 2 cases (3%) vertebroplasty was complicated by intracanal leakage of cement. Conclusions. Percutaneous vertebroplasty is well tolerated by patients. Filling with cement is effective in the treatment of osteoporotic compression fractures and of vertebral angiomas.  相似文献   
63.
In neoplastic disorders, endothelial cells take part in tumor progression and also influence the recovery of hematopoiesis after high-dose chemotherapy. Measurements of circulating endothelial cells (CEC), their subsets and kinetics were taken in patients with lymphoid malignancies (37 multiple myeloma, ten lymphoma) during autologous hematopoietic stem cell transplantation (HSCT). CEC were evaluated by four-color flow cytometry at different time points. Additionally levels of angiopoietins 1 and 2 were evaluated by ELISA assay. The baseline number of CECs and their subsets in patients were higher than in the control group. The median CEC number dropped significantly after transplantation (from 9.5/μL to 6.2/μL, p?<?0.001). Apoptosis of CECs 24 h after chemotherapy was enhanced in comparison to baseline values (median apoptotic CEC number 4.15/μL vs 3.1/μL; p?<?0,001). The time for neutrophil engraftment was shorter for patients with a low apoptotic CEC count at baseline as compared to those with a high apoptotic CEC count (median time to engraftment 13 vs. 16 days respectively, p?=?0.04). We observed an adverse correlation of progenitor CEC numbers measured 1 h after transplantation with the time to neutrophil engraftment (r?=??0.49, p?=?0.008). We also found a negative correlation between the number of CECs originating from microvessels measured 1 h after transplantation, and the time to neutrophil engraftment (r?=??0.39, p?=?0.04). Baseline angiopoietins 1 and 2 concentration did not influence the post-transplant regeneration time. CEC numbers significantly change during autologous HSCT. Our results suggest that progenitor CECs and CECs derived from microvessels both take part in successful engraftment.  相似文献   
64.
The authors describe the case of survival for the period of 10 years after brain metastasis surgery and removal of the left lung upper lobe due to adeno-squamous cells carcinoma. Surgery did not generate any complications. Within 8 years after the surgery the radiological examination showed infiltrations resembling changes typical for tuberculosis. Microbiological analysis showed a culture of Mycobacterium kansasi leading to diagnosis of mycobacteriosis. Hence the antituberculous treatment was extended to 12 months to be interrupted due to liver damage. Two years later the patient experienced incident of haemoptysis. Detailed examination and assessment of the respiratory tract condition revealed COPD without features of renewal of the neoplastic process or infection by Mycobacterium tuberculosis or mycobacterium other than tuberculosis. This case demonstrates that aggressive surgical approaches to lung cancer with solitary cerebral metastasis significantly improve patient survival and justifies its widespread use.  相似文献   
65.
Angiogenesis plays an important role in the biology of hematological malignancies, including essential thrombocythemia (ET) and polycythemia vera (PV). Some data suggests that it has a role in the pathogenesis of thrombosis, the major clinical problem in ET and PV. The number of different subpopulations of circulating endothelial cells (CECs), plasma levels of vascular endothelial growth factor (VEGF), soluble vascular endothelial growth factor receptor 1 and 2 (sVEGFR-1,2) and placenta growth factor (PlGF) were determined in 30 patients with ET and 16 patients with PV. Correlations between angiogenesis and JAK2-V617F mutational status, risk factors for thrombosis and coagulation activation markers were also assessed. The number of CEC subpopulations, were markedly higher in ET and PV patients, irrespective of JAK2-V617F status, when compared to the control group. The median values of activated CECs were markedly higher in PV patients with WBC >8.7 (×109/l). Significantly higher VEGF plasma levels were found in ET patients and a similar trend was seen in PV patients in relation to healthy volunteers. The plasma levels of sVEGFR-1 were significantly higher, and PlGF levels markedly lower, in the ET and PV group than in controls. Our study also demonstrated markedly increased levels of D-dimer and TAT complexes in the patient groups. In conclusion, we found that angiogenesis, as measured by CEC numbers, is increased in ET and PV patients regardless of JAK2-V617F mutational status. Our results demonstrated that angiogenic cytokines interact with known thrombotic risk factors. We confirmed the coagulation activation in ET and PV patients but found no differences in levels of coagulation activation markers in relation to JAK2-V617F mutational status.  相似文献   
66.
We studied the effects of p27 and CHEK2 variants on prostate and colon cancer risk in a case-control study. Modest effects on prostate cancer risk were observed for both CHEK2 missense and truncating variants. However, the excess cancer risk was restricted to the subgroup of men who were homozygous for the VV genotype in codon 109 of the p27 gene. Among men with the VV p27 genotype, the odds ratios associated with truncating and missense CHEK2 mutations were 3.1 (P < 0.0001) and 1.9 (P < 0.0001), respectively. Among men with other p27 genotypes (GG and VG), the odds ratios were 1.5 and 1.2 for truncating and missense CHEK2 mutations, respectively, and were not statistically significant. The interaction between CHEK2 and p27 was confirmed in a group of patients with colon cancer. Thus, it seems that the clinical expression of CHEK2 variant alleles on prostate and colon cancer risk may be restricted to individuals with a specific genotype (VV) of the p27 gene. Two-gene models provide numerous challenges for gene identification and cancer risk assessment.  相似文献   
67.
PURPOSE: We have investigated T Lymphocytes ability for CD69 molecule induction in presence and absence of monocytes in idiopathic uveitis. MATERIAL AND METHODS: Twenty-five children with idiopathic uveitis were studied. The control group consisted of 12 healthy children. Peripheral blood mononuclear cells (PBMCs) were isolated from heparinised venous blood, by density gradient centrifugation. CD69 expression was cytometrically assessed on freshly isolated and cultured T lymphocytes. RESULTS: CD69 expression on freshly isolated peripheral blood T lymphocytes was low in both studied groups. LPS-stimulated monocytes added to cultures of T lymphocytes induced increase in CD69 expression but significantly lower in children with idiopathic uveitis compare to healthy children.  相似文献   
68.
The basic problem in decompression is the limit of maximum tolerable change of pressure after diving. Due to the number of parameters involved in decompression models (bottom time, ambient pressure, exposition profile, content of breathing mixtures, properties of inert gases) the number of possible solutions is theoretically unlimited. Since the beginning of modern decompression models the starting point has been direct saturation decompression using air. The generally accepted form of solution is the linear relation between tolerable pressure P2 after saturation exposition to pressure P1 described by the equation in the form P1 = P2 x A + B, where A and B are parameters obtained by experiments. Since the introduction of this equation values of parameters have been changing in order to decrease the rate of decompression illness. The aim of this study was to analyse and interpret the trend of those changes. Sixteen published models, including the one developed in our center, were compared and gradual change of parameters was identified. This trend should result in safer decompression systems.  相似文献   
69.
The quantitative determination of coumarins, flavonoids and chlorogenic acid in the leaves and underground parts of Scopolia carniolica Jacq., S. lurida Dun. and S. sinensis Hemsl. using the RP-HPLC method has been described.  相似文献   
70.
Toluene is a major component of numerous commercial organic solvent formulations. It is often listed among the chemicals capable of producing the organic solvent syndrome and a neurobehavioral hypersensitivity condition. The hypersensitivity condition (continued long-term intensification of some behavioral reactions in response to pharmacological or environmental stressors) is usually associated with the increased tonus of the functional dopaminergic system. The aim of our current research was to determine whether, under conditions of inhalation exposure, toluene can produce long-term behavioral changes or modify the intensity of the behavioral response to apomorphine, a dopaminergic receptor agonist. In our experiment, male rats were exposed to 25, 100 and 250 ppm toluene for 4 weeks (5 days/week, 6h/day). The following behaviors were tested: finding water in a radial maze; open field motor activity, acquiring the conditional response of passive avoidance; sensitivity to a thermal pain stimulus (hot plate test) and changes in this sensitivity caused by stress; and acquiring the conditional response of two-directional active avoidance. The behavioral response to apomorphine, i.e. the increased spontaneous locomotor activity, was assessed on day 10 after the termination of the exposure in the rotary drum test. In the behavioral experiment, significant differences between groups were recorded only for the hot plate test; in the 100 and 250 ppm rats, electric-shock-related anxiety response was stronger than in the control group. In the experiment using pharmacological provocation, the behavioral response to apomorphine in the rats exposed to 100 ppm or 250 ppm toluene was significantly lower. Our results indicate that low concentrations of toluene may produce long-term behavioral changes in rats. However, these changes seem to be linked with reduced rather than increased functional tonus of the dopaminergic system.  相似文献   
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