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101.
OBJECTIVE: To test the hypothesis that inhibition of protein kinase (PK) activity or proteolysis inhibits ovulation. DESIGN: Rats were injected intrabursally with protein kinase (H9 or staurosporin) or proteinase (alpha 2-macroglobulin) inhibitors and oocyte release was evaluated. SETTING: Clinical Research Laboratory, Center for Reproductive Medicine, University of Kentucky Medical Center. PARTICIPANTS: Immature rats stimulated with pregnant mare serum gonadotropin. INTERVENTIONS: Staurosporin (1 or 10 microM), H9 (1 mM), alpha 2-macroglobulin (835 microIU of activity); or vehicle was injected into the right ovarian bursa. The left ovarian bursa remained intact. Animals immediately received human chorionic gonadotropin (hCG). MAIN OUTCOME MEASURES: Analysis of oocyte release and ovarian morphology. RESULTS: Oocyte release from the inhibitor-treated side decreased for the H9 group (8.1 +/- 1.9 fewer oocytes released, P less than 0.001) and the 10 microM staurosporin group (5.5 +/- 0.6, P less than 0.001). No change in oocyte release was observed in the 1 microM staurosporin, alpha 2-macroglobulin, or vehicle injected groups. Histologic examination of vehicle treated ovaries demonstrated numerous developing corpora lutea (CL; 20.5 +/- 2.1 CL/ovary) and a lack of preovulatory follicles. In contrast, ovaries treated with PK inhibitors contained unruptured preovulatory follicles coincident with fewer forming CL (11.5 +/- 3.5 CL/ovary). CONCLUSIONS: Inhibition of PK activity in vivo suppresses ovulation, demonstrating that protein phosphorylation plays an important intermediary role in the ovulatory process.  相似文献   
102.
We studied CFU-GM recovery from bone marrow samples frozen either in a machine for controlled-rate freezing or in a -70 degrees C freezer. We found no statistically significant difference between the two methods. Cooling-curve investigations also demonstrated that it was possible to obtain satisfactory cooling rates simply by manipulation of the shape and volume of the marrow and its container. Five patients received a total of six successful autografts for which their marrow cells were frozen without controlled-rate freezing. Thus it is not necessary to use a sophisticated machine in order to obtain satisfactory cryopreservation of human marrow stem cells.  相似文献   
103.
BACKGROUND. Cisplatin and 5-fluorouracil have noted synergy in preclinical systems. The authors combined methotrexate with infusional cisplatin and 5-fluorouracil in an attempt to produce a regimen with improved activity in advanced NSCLC. METHODS. Twenty-six ambulatory patients with previously untreated non-small cell lung cancer were treated with continuous-infusion cisplatin (25 mg/m2/day for 5 days), 5-fluorouracil (800 mg/m2/day for 5 days), and intermediate-dose methotrexate (200 mg/m2 on days 15, 22), followed by leucovorin rescue (PFM regimen). RESULTS. Patients received a median of four cycles of therapy. Two patients had a complete response, and 10 had a partial response (overall response rate, 46.2% or 12 of 26). The median time to treatment failure was 22.5 weeks; the median survival was 55 weeks from the start of chemotherapy. There were no toxic deaths attributed to chemotherapy. Thrombocytopenia was the only Grade 4 toxicity (27%). Grade 1/4 and 2/4 peripheral neuropathy occurred in 17 of 26 patients (66%) and was associated with a cumulative cisplatin dose of more than 300 mg/m2. CONCLUSIONS. PFM (using continuous-infusion cisplatin) produced a high response rate but resulted in an high incidence of low-grade peripheral neuropathy.  相似文献   
104.
BACKGROUND AND PURPOSE: Neutrophils are critically involved with ischemia and reperfusion injury in many tissues but have not been studied under conditions of reperfusion after focal cerebral ischemia. The present studies were conducted to confirm our previous observations quantifying neutrophils in rat permanent focal stroke using a myeloperoxidase activity assay and to extend them to transient ischemia with reperfusion. In addition, leukotriene B4 receptor binding in ischemic tissue was evaluated as a potential marker for inflammatory cell infiltration. METHODS: Histological, enzymatic, and receptor binding techniques were used to evaluate neutrophil infiltration and receptor binding in infarcted cortical tissue 24 hours after permanent middle cerebral artery occlusion (n = 25) or temporary occlusion for 80 (n = 12) or 160 (n = 22) minutes followed by reperfusion for 24 hours in spontaneously hypertensive rats. RESULTS: Sham surgery (n = 26) produced no changes in any parameter measured. After permanent middle cerebral artery occlusion, neutrophil accumulation was observed histologically, but the infiltration was moderate and typically within and adjacent to blood vessels bordering the infarcted cortex. After temporary middle cerebral artery occlusion with reperfusion, marked neutrophil infiltration was observed throughout the infarcted cortex. Myeloperoxidase activity was increased (p less than 0.05) after permanent occlusion and to a greater extent after temporary occlusion with reperfusion. Myeloperoxidase activity (units per gram wet weight) in ischemic cortex was increased over that in nonischemic (control) cortex 32.2-fold, 54.6-fold, and 92.1-fold for permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (p less than 0.05). Sham surgery produced no changes in myeloperoxidase activity. Leukotriene B4 receptor binding also was increased (p less than 0.05) after focal ischemia and paralleled the increases in myeloperoxidase activity. Ischemic cortex-specific receptor binding (femtomoles per milligram protein) was 3.87 +/- 0.63 in sham-operated rats and 4.57 +/- 0.98, 8.98 +/- 1.11, and 11.12 +/- 1.63 for rats subjected to permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (all p less than 0.05 different from sham-operated). Cortical myeloperoxidase activity was significantly correlated with the degree of cortical leukotriene B4 receptor binding (r = 0.66 and r = 0.79 in two different studies, p less than 0.01). CONCLUSION: These data indicate that neutrophils are involved in focal ischemia and that there is a dramatic accumulation of neutrophils in infarcted tissue during reperfusion that can be quantified using the myeloperoxidase activity assay. Leukotriene B4 receptor binding increases in infarcted tissue in a parallel manner, which suggests that the increased leukotriene B4 binding is to receptors located on the accumulating neutrophils.  相似文献   
105.
We studied blood pressure and natriuretic responses to acute salt loading, and the effect of non-steroidal anti-inflammatory agents on these responses, in five healthy normotensive women aged 65 to 71 years. Five women aged 25 to 31 years acted as controls. Intravenous saline loading, with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h. Baseline blood pressures were higher in the elderly. Saline infusion without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in the older group only. Ibuprofen increased baseline SBP in the elderly (129 +/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen again raised blood pressure by about 25 mmHg in the elderly only. The elderly group showed markedly increased sodium excretion during saline loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP or sodium excretion in controls. Ageing appears to increase susceptibility to salt retention and hypertension from non-steroidal anti-inflammatory agents.   相似文献   
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Increasing numbers of patients are undergoing diagnostic catheterization as outpatients; however, a small proportion of patients requires hospital admission following the procedure. Unplanned admissions after consecutive outpatient cardiac catheterizations performed during 1 year were prospectively reviewed to determine the incidence of and reasons for admission. Among 847 patients undergoing outpatient cardiac catheterization, 130 patients (15%) required hospital admission after the procedure. Admitted patients were divided into four groups: patients undergoing immediate percutaneous transluminal coronary angioplasty (PTCA) (Group 1; 33%), patients with severe cardiac disease requiring urgent intervention (Group 2; 48%), patients suffering complications or hemodynamic instability (Group 3; 15%), and patients whose procedures were completed too late to allow same-day discharge (Group 4; 4%). Patients over 65 were more likely to require admission and women were more likely to be admitted with complications or hemodynamic instability. Findings are compared with results of other outpatient series, and implications regarding appropriate setting for outpatient catheterization are discussed.  相似文献   
110.
Adherence of bacteria to corneal epithelium is a prerequisite for corneal infection. We used two methods to study the binding of Pseudomonas aeruginosa and Staphylococcus aureus to rabbit corneal epithelial cells in culture. In the first method, rabbit corneal epithelial cells grown on glass slides were incubated with P. aeruginosa or S. aureus (10(7) CFU/ml) at room temperature for 90 min, and the bacterial binding to the epithelial cells was examined by light microscopy. Both P. aeruginosa and S. aureus bound to epithelial cells. P. aeruginosa was bound to the cell periphery whereas S. aureus was bound randomly to the cell surface. In the second method, suspension cultures of corneal epithelial cells were used. In contrast to the findings in cultures on slides, binding pattern with cells in suspension was similar for both species and resembled that for S. aureus in cultures on slides. A much greater number of P. aeruginosa (186 +/- 11 bacteria/epithelial cell) than S. aureus (30 +/- 1.5 bacteria/epithelial cell) bound to epithelial cells grown on glass slides. In contrast, a similar number of P. aeruginosa (25 +/- 5.1) and S. aureus (20 +/- 4.7) bound to epithelial cells grown in suspension cultures. Using either method, Escherichia coli and Streptococcus pyogenes did not bind significantly (less than 5/cell) to corneal epithelial cells. The above methods should prove useful for characterization of bacterial binding to corneal epithelial cells in culture.  相似文献   
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