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1.
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.  相似文献   
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The goal of the present study was to test the impact of administration time of the angiotensin II type 1-receptor blocker candesartan on cerebral blood flow (CBF), infarct size, and neuroscore in transient cerebral ischemia. Therefore, 1-hour middle cerebral artery occlusion (MCAO) was followed by reperfusion. Rats received 0.5-mg/kg candesartan intravenously 2 hours before MCAO (pretreatment), 24 hours after MCAO, every 24 hours after MCAO, or 2 hours before and every 24 hours after MCAO. Infarct size (mm3) and a neuroscore at day 7 were compared with controls. CBF was quantified by radiolabeled microspheres and laser-Doppler flowmetry. Compared with controls (95 +/- 8), infarct size in candesartan-treated groups was smaller (59 +/- 5, 68 +/- 10, 28 +/- 3, and 15 +/- 3, respectively; P<0.05). Although there was no difference in neuroscore between pretreatment and controls (1.55 +/- 0.18, 1.80 +/- 0.13), other treatment regimens resulted in improved neuroscores (1.33 +/- 0.16, 1.11 +/- 0.11, 0.73 +/- 0.15; P<0.05). CBF in pretreated animals at 0.5 hours after MCAO was significantly higher than in controls (0.58 +/- 0.09 mL x g(-1) x min(-1) and 44% +/- 7% of baseline compared with 0.49 +/- 0.06 mL x g(-1) x min(-1) and 37% +/- 6%, microspheres and laser-Doppler flowmetry; P<0.05). Thus, candesartan reduces infarct size even if administered only during reperfusion. Apart from pretreatment, other treatment regimens result in significantly improved neuroscores. In the acute phase of cerebral ischemia, candesartan increases CBF.  相似文献   
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实验性单纯疱疹性角膜炎的组织病理学研究   总被引:1,自引:0,他引:1  
目的:动态观察1型单纯疱疹病毒(HSV-1)感染角膜后的组织病理改变。方法:BALB/c小鼠眼角膜接种HSV-1(KOS株)以诱发单纯疱疹性角膜炎(HSK)。分别收集正常眼球及感染后第2、7、14天的感染眼球,组织学观察结膜及角膜的病理过程。结果:感染后第2天,中性粒细胞、淋巴细胞及其他单核细胞浸润结膜并在第7-14天间快速向中央角膜扩散。结论:在HSK发展中,中性粒细胞浸润导致进行性的组织破坏。  相似文献   
5.
Wilson's disease (WD) is an inherited disorder of copper metabolism yielding marked motor deficits, including a severely disabling tremor. As a structural correlate of the disease, a variety of cerebral abnormalities has been revealed. However, the relationship between motor deficits and cerebral lesions has remained largely unknown. Here, we investigated correlation between WD tremor and cerebral magnetic resonance imaging (MRI) findings. Cerebral MRI abnormalities in 6 symptomatic WD patients were compared to findings in 6 asymptomatic WD patients and 10 healthy controls. All patients were treated with long-term copper chelating therapy. Motor symptoms including tremor were determined by Unified Parkinson's Disease Rating Scale Part III (UPDRS-III). MRI findings in symptomatic WD patients revealed significant symmetric T2*-weighted hypointense signal alterations of globus pallidus, head of the caudate nucleus, and substantia nigra. In contrast, MRI of asymptomatic WD patients did not differ from healthy controls. Correlation analysis revealed a significant positive correlation between MRI basal ganglia lesions and UPDRS action tremor score. Our results demonstrate for the first time that Wilson's disease tremor is associated with lesions of the globus pallidus, the head of the caudate nucleus, and the substantia nigra.  相似文献   
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It has been extensively documented the role of the indirect pathway of allorecognition in allograft rejection. However, recent data demonstrate that the manipulation of this pathway could be also sufficient to promote prolongation of allograft survival. In the present study we evaluated the effect of preoperative immunization with the WF-specific MHC class II peptides RT1.D2 and RT1.B2 in combination with low-dose CsA from days 0 to 7 (5 mg/kg/day) and from days 8 to 30 (1 mg/kg/day) after WF small bowel transplantation. Seven days before and on the day of transplantation, LEW recipients were immunized with the two WF MHC class II peptides RT1.B2 and RT1.D2. The CsA monotherapy induced an allograft survival of 49.3 +/- 6.1 days. MHC class II peptide immunization had a limited effect on allograft survival for RT1.D2 (47.1 +/- 3.8 days) and induced prolongation of allograft survival for RT1.B2 (73.6 +/- 34.6 days). This effect seems to be based on the absence or silence of RT1.B2-reactive T cells and rejection seems to be correlated with the presence of RT1.B2-specific T cells in the late phase. Therefore, the combination of RT1.B2 with low-dose CsA shifts the immunological response and protects small bowel allograft rejection.  相似文献   
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Background: Thymusderived lymphocytes play a critical role in the development of herpes simplex keratitis (HSK). T-cell subsets defined by their expression of various T-cell receptor (TCR) Vß segments were studied following corneal HSV-1 infection (p.i.). Methods: Conjunctiva, corneal limbus and corneal stroma of two inbred BALB/c congenic mouse strains which differ only in the gene products closely linked to the Igh-1 locus on chromosome 12 were analyzed. Results: While C.B-17 mice (Igh-1b) were resistant to HSK, C.AL-20 mice (Igh-1d) clinically developed severe necrotizing keratitis by day 11 p.i. The corneal stroma of C.B-17 mice remained clear, while it was increasingly infiltrated by mononuclear cells and neutrophils in C.AL-20 mice by day 11 p.i. In C.B-17 mice, Thy1.2+ cells were found in the conjunctiva between days 2 to 4 p.i., and subsequently decreased. Only a few Thyl.2+ cells were found in the limbus, and no such cells were found in the stroma. In contrast, in C.AL-20 mice the numbers of Thyl.2+ cells (activated CD4+, Vß8+ T cells) profoundly increased in the conjunctiva by day 4 p.i. These cells infiltrated the limbus between days 7 and 11 p.i. and eventually entered the stromal tissue by day 11 p.i. Conclusions: Our data suggest that the HSV-1-induced corneal tissue destruction is mediated by mononuclear cells and neutrophils and that these cells are probably attracted into the cornea by cytokines elaborated by activated CD4+, Vß8+ T cells.Presented as a paper at the ECORA Meeting, 4–7 October 1993, Bonn  相似文献   
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BACKGROUND: Our purpose was to develop and evaluate protocols for selective immunosuppression after liver transplantation using the monoclonal antibodies (mAbs) NDS-61, directed against the interleukin-2 receptor (CD25), and 1A29, directed against the intercellular adhesion molecule-1 (CD54), in combination with subtherapeutic cyclosporine (CsA). METHODS: Orthotopic rat liver transplantation (ORLT) was performed in a DA-to-LEW strain combination. Immunosuppression was administered from day 0 to +13. Functional parameters such as survival time, body weight, and serum bilirubin levels were measured and the liver grafts were evaluated histologically. RESULTS: A stepwise tapering of CsA from 3 to 0.25 mg/kg/day reduced the long-term survival rate. All animals died at a CsA dosage of 0.25 mg/kg/day, which was therefore defined as subtherapeutic. Monotherapy with the anti-CD25 mAb was performed at dosages of 600 and 1800 microg/kg/day. The lower mAb dosage resulted in a long-term survival rate of 12% and was defined as subtherapeutic. The combination therapy of CsA (0.25 mg/kg/day) and anti-CD25 mAb (600 microg/kg/day) produced a synergistic effect and led to a long-term survival rate of 84%. This survival rate was significantly higher than those after either CsA (P<0.005) or anti-CD25 mAb (P<0.001) monotherapy. Both dosages (10 and 30 microg/kg/day) of anti-CD54 mAb monotherapy as well as anti-CD54 mAb combined with a subtherapeutic dosage of CsA were ineffective in preventing acute allograft rejection. The addition of anti-CD54 mAb (30 microg/kg/day) to combined CsA plus anti-CD25 mAb therapy (triple therapy), however, increased the long-term survival rate to 100%. In the triple therapy group there was no rejection process in the liver allografts at any time, and donor-specific tolerance could be shown by donor-specific and third-party heterotopic heart transplantation. CONCLUSIONS: The synergistic action of subtherapeutic CsA plus anti-CD25 mAb NDS-60 could be demonstrated, whereas anti-CD54 mAb only had a positive effect in a triple therapy group. Triple therapy prevented both acute and chronic rejection and induced donor-specific tolerance.  相似文献   
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