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31.
Preduodenal mechanisms in initiating gallbladder emptying in man 总被引:2,自引:0,他引:2
S Ellenbogen S A Jenkins J S Grime M Critchley C R Mackie J N Baxter 《The British journal of surgery》1988,75(10):940-945
The existence of preduodenal phases of gallbladder emptying in normal volunteers was investigated by evaluating the effect of sham feeding a sandwich (chew and spit) (n = 15), the sight and smell of food followed by sham feeding a cooked meal (n = 15), and gastric distension (intragastric balloon tube) (n = 9) on gallbladder emptying and comparing these responses with those after ingestion of a standard meal (n = 14). A control group given no intestinal stimuli were studied to determine the frequency of spontaneous emptying during fasting (n = 18). 99mTc-EHIDA (2,6 diethylphenylcarbamoylmethyliminodiacetic acid) was used as the biliary tracer. The frequency of gallbladder emptying during fasting was 0.0045/min. Thus, in any 20 min period emptying occurred spontaneously in only about 1 in 11 volunteers. Significant emptying (greater than 5 per cent over 20 min) occurred in 8 out of 15 volunteers after sham feeding a sandwich (P less than 0.001 versus control), in 8 out of 15 volunteers after sham feeding a cooked meal (P = 1.0 versus sandwich sham feed, n.s.), in 6 out of 9 volunteers after gastric distension (P less than 0.001 versus control) and in 14 out of 14 volunteers after meal ingestion. The rate of emptying was significantly greater in the gastric distension and meal ingestion groups compared with other groups (P less than 0.05). However, the emptying rate after sham feeding was not significantly different from spontaneous gallbladder emptying (P greater than 0.05, n.s.). There was no significant difference in time to onset of emptying between the four stimulus groups (P greater than 0.05, n.s.). These results suggest that pre-duodenal stimuli can evoke gallbladder emptying in man, although the precise physiological significance of this phenomenon remains to be established. 相似文献
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A D Kriketos D G Carey A B Jenkins D J Chisholm S M Furler L V Campbell 《Diabetic medicine》2003,20(4):294-300
AIMS: To examine the relationships between body composition and changes in fasting glycaemia, and in indices of insulin secretion and insulin action over 6 years in females with a family history of Type 2 diabetes with or without prior gestational diabetes ('at risk' group, AR) and control females (control group, C). METHODS: At baseline and at follow-up, an oral glucose tolerance test and dual energy X-ray absorptiometry assessment of body composition were performed. Indices of insulin resistance (HOMA R') and insulin secretion (HOMA beta') were obtained from fasting insulin and glucose concentrations. RESULTS: At baseline, the groups were similar for age, body mass index, fasting levels of plasma glucose and insulin, HOMA R' and HOMA beta'. Despite similar total body fatness, AR had significantly greater waist circumference and central fat (both P < 0.02) compared with C. At follow-up there was a significant increase in central adiposity only in AR, and the fasting plasma glucose (FPG) level was higher in AR compared with C (5.0 +/- 0.2 vs. 4.3 +/- 0.2 mmol/l, P = 0.02). This rise in plasma glucose in AR was related to a decline in HOMA beta' (r = 0.45, P = 0.0065). Both the baseline and the increments in total and central abdominal fat mass were associated with the time-related decline in HOMA beta'. CONCLUSIONS: Six years after initial assessment, AR showed deterioration in FPG levels due predominantly to a decline in insulin secretion index without major change in insulin resistance index. Importantly, baseline body fatness (especially central adiposity), as well as increases in fatness with time, were the major predictors of the subsequent decline of insulin secretion index and the consequent rise in FPG. 相似文献
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Summary Salvage radical retroperitoneal node dissection for large residual masses remaining after chemotherapy for testicular cancer was performed in 41 patients. In 10 instances it was possible to carry out a radical removal and attempt to preserve the sympathetic chain on one side. Ejaculation was preserved in 8 of these cases. Where removal of the mass was complete (33 cases) active cancer was present in 6, only one of whom developed tumor recurrence. Salvage node dissection is worthwhile, and in about 25% of cases can be performed with preservation of ejaculation. 相似文献
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Ganciclovir therapy of severe cytomegalovirus infections in solid-organ transplant recipients 总被引:5,自引:0,他引:5
The clinical and virologic efficacy of ganciclovir (9-[1,3-dihydroxy-2-propoxymethyl]guanine) in the treatment of severe CMV infections in solid organ transplant recipients was investigated. Twelve patients (9 liver and 3 kidney transplant recipients) with CMV retinitis, esophagitis, hepatitis, or pneumonia received ganciclovir at a dose of 0.75-7.5 mg/kg/day for 10-30 days (mean duration 17 days). Clinical stabilization or improvement occurred in 8 patients (67%). Serial liver biopsies in 6 liver allograft recipients with CMV hepatitis demonstrated substantial histologic improvement on treatment. Of 6 patients with CMV pneumonia, 4 (67%) recovered and survived. Cultures of blood and other sites became negative in 9 patients (75%). Three patients (25%) had recurrent viral shedding after treatment, but none of these relapsed with invasive infections. Mild neutropenia was the only side effect encountered but was frequent (67%). The overall survival rate was 50%. Ganciclovir is effective in reducing CMV shedding in solid organ transplant recipients and is well tolerated. Our experience suggests a clinical benefit as well in patients with severe, invasive CMV disease. Relapse, in contrast to patients with the acquired immunodeficiency syndrome, is infrequent. 相似文献
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Sepsis-induced lung injury and the effects of ibuprofen pretreatment. Analysis of early alveolar events via repetitive bronchoalveolar lavage. 总被引:2,自引:0,他引:2
J K Jenkins P D Carey K Byrne H J Sugerman A A Fowler 《The American review of respiratory disease》1991,143(1):155-161
Current knowledge of alveolar pathophysiology during early sepsis-induced acute lung injury (ALI) and the role of resident alveolar macrophages (AM) in mediating alveolar inflammatory events during sepsis is limited. Further, the effects of ibuprofen pretreatment upon alveolar pathophysiology and AM function during early sepsis-induced ALI is unclear. Utilizing repetitive bronchoalveolar lavage (BAL) in a porcine model of sepsis-induced ALI, we studied changes in alveolar cellular constituents, BAL protein content and molecular composition, and AM superoxide anion (O2-.) generation during early sepsis. The neutrophil percentage of recovered alveolar cells (17 +/- 8%, t = 300 min versus 2 +/- 1%, t = 0; p = 0.06) and the bronchoalveolar lavage total protein content (493 +/- 110 micrograms/ml, t = 300 min versus 109 +/- 18 micrograms/ml, t = 0; p less than 0.05) increased in septic animals. Increases in BAL fluid total protein were primarily due to low-molecular-weight plasma protein, indicating relative preservation of alveolar-capillary membrane size selectivity. Alveolar macrophages harvested following 300 min of sepsis generated significantly less O2-. following phorbol myristate acetate (PMA) stimulation compared to AM harvested at baseline. Ibuprofen pretreatment of septic animals completely blocked leakage of plasma proteins into the alveoli and attenuated neutrophil migration but did not prevent downregulation of AM O2-. generation. Increased alveolar-capillary membrane permeability, neutrophil migration into the alveoli, and downregulation of AM oxidant generation occur within hours of the onset of sepsis. Ibuprofen pretreatment significantly attenuates early sepsis-induced ALI without altering sepsis-induced AM dysfunction. 相似文献