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101.
B7-H3 negatively regulates Th1-mediated immune responses. Here, we aimed to investigate whether B7-H3 is involved in the development of murine experimental allergic conjunctivitis (EC), which is predominantly mediated by Th2 cells. Intraperitoneal injection of anti-B7-H3 Ab during the induction phase of EC significantly augmented the severity of EC evaluated as conjunctival eosinophil numbers and Ag-induced IL-5 production by splenocytes. Injection of anti-B7-H3 Ab during the effector phase of EC did not significantly affect the severity of EC. In addition, transfer of Ag-primed splenocytes treated with anti-B7-H3 Ab in vitro did not significantly affect the severity of EC, compared to the splenocytes treated with the control Ab. Thus, regulation of EC by blocking of B7-H3 was observed during the induction phase but not the effector phase. Moreover, this study provides a new notion that B7-H3 regulates not only Th1-mediated but also Th2-mediated immune reactions.  相似文献   
102.
HIV-1 evolution in the envelope gene (env) was analyzed in four asymptomatic antiretroviral therapy na?ve patients with typical and slow disease progression rates. In typical progressors, viral populations were monophyletic and two distinct evolutionary patterns were observed. In one patient, HIV-1 evolution displayed a strong temporal structure similar to the consistent pattern previously described. In the other, viral evolution displayed a lack of temporal structure with no increase in genetic heterogeneity and divergence over time. In slow progressors, several clades were observed in viral populations. However, analysis within the major sub-population revealed the same two evolutionary patterns described for typical progressors. Synonymous and non-synonymous substitution rate analyses indicated that positive selection was the major force driving HIV-1 evolution in viral populations with temporal structure, while evolution in viral populations with an atemporal structure was dominated by genetic drift and purifying selection. These results support the existence of distinct patterns of env evolution in untreated HIV-1-infected patients.  相似文献   
103.
Contact hypersensitivity (CHS) is a cutaneous immune reaction mediated mainly by antigen-specific effector T cells and is regarded as a model for Th1/Tc1-mediated inflammation. However, recent reports have suggested pivotal roles of B cells in CHS. CD19 serves as a positive B-cell response regulator that defines signaling thresholds critical for B-cell responses. In the current study, we assessed the role of the B-cell-specific surface molecule CD19 on the development of CHS by examining CD19-deficient mice. Although CD19-deficient mice are hyposensitive to a variety of transmembrane signals, CD19 loss resulted in increased and prolonged reaction of CHS, suggesting an inhibitory role of CD19 expression in CHS. Sensitized lymph nodes and elicited ear lesions from CD19-deficient mice exhibited Th1/Tc1-shifted cytokine profile with increased interferon-gamma expression and decreased interleukin-10 expression. Adoptive transfer experiments revealed that CD19 expression in recipient mice was required for optimal suppression of CHS response, indicating its role in the elicitation phase. Furthermore, spleen B cells, especially marginal zone B cells, from wild-type mice were able to normalize exaggerated CHS reactions in CD19-deficient mice. Thus, CD19 expression in B cells is critical for termination of CHS responses, possibly through the function of regulatory B cells.  相似文献   
104.
105.
Bone strength is predominantly determined by bone density, but bone microarchitecture also plays an important role. We examined whether trabecular bone score (TBS) predicts the risk of vertebral fractures in a Japanese female cohort. Of 1950 randomly selected women aged 15 to 79 years, we analyzed data from 665 women aged 50 years and older, who completed the baseline study and at least one follow‐up survey over 10 years, and who had no conditions affecting bone metabolism. Each survey included spinal imaging by dual‐energy X‐ray absorptiometry (DXA) for vertebral fracture assessment and spine areal bone mineral density (aBMD) measurement. TBS was obtained from spine DXA scans archived in the baseline study. Incident vertebral fracture was determined when vertebral height was reduced by 20% or more and satisfied McCloskey‐Kanis criteria or Genant's grade 2 fracture at follow‐up. Among eligible women (mean age 64.1 ± 8.1 years), 92 suffered incident vertebral fractures (16.7/103 person‐years). These women were older with lower aBMD and TBS values relative to those without fractures. The unadjusted odds ratio of vertebral fractures for one standard deviation decrease in TBS was 1.98 (95% confidence interval [CI] 1.56, 2.51) and remained significant (1.64, 95% CI 1.25, 2.15) after adjusting for aBMD. The area under the receiver operating characteristic curve of TBS and aBMD combined was 0.700 for vertebral fracture prediction and was not significantly greater than that of aBMD alone (0.673). However, reclassification improvement measures indicated that TBS and aBMD combined significantly improved risk prediction accuracy compared with aBMD alone. Further inclusion of age and prevalent vertebral deformity in the model improved vertebral fracture prediction, and TBS remained significant in the model. Thus, lower TBS was associated with higher risk of vertebral fracture over 10 years independently of aBMD and clinical risk factors including prevalent vertebral deformity. TBS could effectively improve fracture risk assessment in clinical settings. © 2014 American Society for Bone and Mineral Research.  相似文献   
106.

Background

Surgical site infection (SSI) after spinal surgery is a devastating complication. Various methods of skin closure are used in spinal surgery, but the optimal skin-closure method remains unclear. A recent report recommended against the use of metal staples for skin closure in orthopedic surgery. 2-Octyl-cyanoacrylate (Dermabond; Ethicon, NJ, USA) has been widely applied for wound closure in various surgeries. In this cohort study, we assessed the rate of SSI in spinal surgery using metal staples and 2-octyl-cyanoacrylate for wound closure.

Methods

This study enrolled 609 consecutive patients undergoing spinal surgery in our hospital. From April 2007 to March 2010 surgical wounds were closed with metal staples (group 1, n = 294). From April 2010 to February 2012 skin closure was performed using 2-octyl-cyanoacrylate (group 2, n = 315). We assessed the rate of SSI using these two different methods of wound closure. Prospective study of the time and cost evaluation of wound closure was performed between two groups.

Results

Patients in the 2-octyl-cyanoacrylate group had more risk factors for SSI than those in the metal-staple group. Nonetheless, eight patients in the metal-staple group compared with none in the 2-octyl-cyanoacrylate group acquired SSIs (p < 0.01). The closure of the wound in length of 10 cm with 2-octyl-cyanoacrylate could save 28 s and $13.5.

Conclusions

This study reveals that in spinal surgery, wound closure using 2-octyl-cyanoacrylate was associated with a lower rate of SSI than wound closure with staples. Moreover, the use of 2-octyl-cyanoacrylate has a more time saving effect and cost-effectiveness than the use of staples in wound closure of 10 cm in length.  相似文献   
107.
108.
Changes in platelet alpha 2 adrenoreceptors and their relation to plasma catecholamine concentrations were studied in 11 patients with acute transmural myocardial infarction. A radiolabelled alpha 2 adrenoreceptor antagonist, [3H]-yohimbine, was used to assay alpha 2 adrenoreceptors on platelet membranes, and plasma catecholamine concentrations were measured by high performance liquid chromatography. The number of platelet alpha 2 adrenoreceptors, the dissociation constant, and plasma noradrenaline and adrenaline concentrations were studied 6.6 (3.3) (mean (SD)) hours after the onset of acute myocardial infarction and one month later. The mean (SD) number of adrenoreceptors increased significantly from 94.5 (50.5) fmol/mg protein immediately after infarction to 157.0 (65.7) fmol/mg protein one month later. The dissociation constant, however, did not change significantly (4.33 (1.40) nmol/l vs 4.37 (1.22) nmol/l). Raised noradrenaline (5.60 (4.37) nmol/l) and adrenaline (0.28 (0.14) nmol/l) concentrations had fallen significantly to normal values (1.21 (0.67) and 0.09 (0.05) nmol/l respectively) a month after infarction. The decrease in the number of alpha 2 adrenoreceptors soon after infarction may be beneficial because such a change will reduce the strength of various reactions to catecholamines, such as vasoconstriction.  相似文献   
109.
We have assessed the sequential changes in left ventricular function and ECG in 39 patients with coronary artery disease (CAD) using an ambulatory ventricular function monitor. Following radionuclide ventriculography, the instrument detectors were placed over the region of the left ventricle and lung, and beat-to-beat left ventricular time activity curve and modified V5 ECG data were continuously monitored for up to 6 hours (mean 2.5 hours), while the patient performed various daily activities. Thirty-six episodes of transient ejection fraction (EF) decrease (6-18%) were recorded in 16 patients, 12 were symptomatic and 24 asymptomatic. ST segment changes were recorded in 6 of the 12 symptomatic and 5 of the 24 asymptomatic episodes. In 10 of the 12 symptomatic episodes, EF began to drop 30 to 90 seconds before the onset of the symptoms. Of 14 episodes of significant ST segment depression in five patients, 11 were associated with a significant EF decrease. We conclude that the combination of left ventricular function and ECG monitoring is a promising means for determining incidence of silent and symptomatic ischemia and for severity of ischemia in patients with CAD.  相似文献   
110.
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