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71.
PURPOSE: To determine the relationship between the length of the ulna as a proportion of height (proportional ulnar length [PUL]), forearm and wrist ranges of motion, and degree of observable deformity in people with hereditary multiple exostoses. METHODS: One hundred forty-two people with hereditary multiple exostoses were examined; 35 were under the age of 15 years and therefore were presumed to be skeletally immature. Elbow, forearm, and wrist motion were measured, and the radius and ulna were palpated for osteochondromas. Ulnar length was estimated as a proportion of height (PUL) in skeletally immature subjects. The relationships between total active motion, number of palpable osteochondromas, and proportional length were examined for one randomly selected limb from each subject. RESULTS: A negative correlation was found between the number of palpable osteochondromas and range of forearm rotation. The degree of forearm motion in those under the age of 15 years was directly related to PUL and indirectly related to the number of palpable osteochondromas. Children whose PUL is within the normal range have a normal range of motion. CONCLUSIONS: In a child with hereditary multiple exostoses affecting the forearm, the PUL is associated with the range of movement and deformity, and it can be a useful adjunct in deciding the appropriate management.  相似文献   
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Periosteal Ewing sarcoma   总被引:3,自引:0,他引:3  
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75.
The aim of this study was to determine the effect of 5-hydroxytryptamine (5-HT) uptake blockade on 5-HT turnover by measuring the concentrations of 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) in brain with the aid of high performance liquid chromatography and electrochemical detection. The indoleamines were measured in the anterior hypothalamus (AH), posterior hypothalamus (PH) and raphe nuclei 30 min after the i.v. injection of either alaproclate (30 mg/kg) or zimelidine (20 mg/kg). The effect of alaproclate was studied in male rats, pro-oestrous female rats, rats ovariectomized and injected s.c. with 20 micrograms oestradiol benzoate (OB) on dioestrus and at 12.00 h of the next day (presumptive pro-oestrus) with 2 mg progesterone (model 1) and rats ovariectomized 3-4 weeks before an s.c. injection of 20 micrograms OB followed 72 h later by an s.c. injection of 2 mg progesterone (model 2). Alaproclate caused a significant decrease in the 5-HIAA/5-HT ratio in the AH and PH of the brain of male rats, in the PH and raphe nuclei in pro-oestrous rats and model 1, and in the raphe nuclei alone in model 2. Zimelidine had no effect on the 5-HIAA/5-HT ratio in any area in model 2. In male rats the injection of parachlorophenylalanine produced a marked reduction in the brain concentrations of 5-HT and 5-HIAA, but the 5-HIAA/5-HT ratio was unchanged by a subsequent injection of alaproclate. None of the pharmacological agents affected significantly the brain concentrations of noradrenaline, dopamine or dihydroxyphenylacetic acid.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
76.
We have investigated the role of progesterone in the mating-induced release of luteinizing hormone (LH) and ovulation in female rats exposed to a 60-day period of constant light (LL). Plasma LH and progesterone concentrations were increased after mating; plasma estradiol concentrations, although not increased after mating, were increased compared with the concentrations in female rats on light-dark (LD) exposure during diestrus, proestrus evening and estrus. Progesterone induced ovulation in about half the number of female rats exposed to long-term LL, and in these animals, there was a significant increase in pituitary responsiveness to luteinizing hormone releasing hormone (LHRH) 5 h after progesterone injection. The magnitude of the priming effect of LHRH was markedly increased 2 h after progesterone treatment. Treatment with sodium pentobarbitone (SP) 15 min before an injection of progesterone, blocked the increase in pituitary responsiveness to LHRH 5 h later, but treatment with SP 4 h before progesterone injection did not block the increase in the magnitude of the priming effect of LHRH. These results suggest that progesterone acts both at the brain and pituitary to facilitate LH release, and that the increase in plasma progesterone produced by mating is at least partly responsible for the LH surge induced by mating in LL rats.  相似文献   
77.
Previous fractures of the hip, spine, or wrist are well-recognized predictors of future fracture, but the role of other fracture sites is less clear. We sought to assess the relationship between prior fracture at 10 skeletal locations and incident fracture. The Global Longitudinal Study of Osteoporosis in Women (GLOW) is an observational cohort study being conducted in 17 physician practices in 10 countries. Women aged ≥55 years answered questionnaires at baseline and at 1 and/or 2 years (fractures in previous year). Of 60,393 women enrolled, follow-up data were available for 51,762. Of these, 17.6%, 4.0%, and 1.6% had suffered 1, 2, or ≥3 fractures, respectively, since age 45 years. During the first 2 years of follow-up, 3149 women suffered 3683 incident fractures. Compared with women with no previous fractures, women with 1, 2, or ≥3 prior fractures were 1.8-, 3.0-, and 4.8-fold more likely to have any incident fracture; those with ≥3 prior fractures were 9.1-fold more likely to sustain a new vertebral fracture. Nine of 10 prior fracture locations were associated with an incident fracture. The strongest predictors of incident spine and hip fractures were prior spine fracture (hazard ratio [HR] = 7.3) and hip (HR = 3.5). Prior rib fractures were associated with a 2.3-fold risk of subsequent vertebral fracture, and previous upper leg fracture predicted a 2.2-fold increased risk of hip fracture. Women with a history of ankle fracture were at 1.8-fold risk of future fracture of a weight-bearing bone. Our findings suggest that a broad range of prior fracture sites are associated with an increased risk of incident fractures, with important implications for clinical assessments and risk model development.  相似文献   
78.
We describe a technique for the accurate and conservative debridement of the ends of divided flexor tendons. We have found this technique particularly useful for the secondary repair of tendons after re-rupture.  相似文献   
79.
The metabolic syndrome is characterized by insulin resistance and abnormal apolipoprotein AI (apoAI) and apolipoprotein B-100 (apoB) metabolism that may collectively accelerate atherosclerosis. The effects of atorvastatin (40 mg/day) and micronised fenofibrate (200 mg/day) on the kinetics of apoAI and apoB were investigated in a controlled cross-over trial of 11 dyslipidemic men with the metabolic syndrome. ApoAI and apoB kinetics were studied following intravenous d(3)-leucine administration using gas-chromatography mass spectrometry with data analyzed by compartmental modeling. Compared with placebo, atorvastatin significantly decreased (P < 0.001) plasma concentrations of cholesterol, triglyceride, LDL cholesterol, VLDL apoB, intermediate-density lipoprotein (IDL) apoB, and LDL apoB. Fenofibrate significantly decreased (P < 0.001) plasma triglyceride and VLDL apoB and elevated HDL(2) cholesterol (P < 0.001), HDL(3) cholesterol (P < 0.01), apoAI (P = 0.01), and apoAII (P < 0.001) concentrations, but it did not significantly alter LDL cholesterol. Atorvastatin significantly increased (P < 0.002) the fractional catabolic rate (FCR) of VLDL apoB, IDL apoB, and LDL apoB but did not affect the production of apoB in any lipoprotein fraction or in the turnover of apoAI. Fenofibrate significantly increased (P < 0.01) the FCR of VLDL, IDL, and LDL apoB but did not affect the production of VLDL apoB. Relative to placebo and atorvastatin, fenofibrate significantly increased the production (P < 0.001) and FCR (P = 0.016) of apoAI. Both agents significantly lowered plasma triglycerides and apoCIII concentrations, but only atorvastatin significantly lowered (P < 0.001) plasma cholesteryl ester transfer protein activity. Neither treatment altered insulin resistance. In conclusion, these differential effects of atorvastatin and fenofibrate on apoAI and apoB kinetics support the use of combination therapy for optimally regulating dyslipoproteinemia in the metabolic syndrome.  相似文献   
80.
PURPOSE: The surgical resident experience with trauma has changed. Many residents are exposed to predominantly nonoperative patient care experiences while on trauma rotations. Data from a large multicenter study were analyzed to estimate surgical resident exposure to trauma laparotomy, diagnostic peritoneal lavage (DPL), and focused abdominal sonography for trauma (U/S). METHODS: Centers completed a self-report questionnaire on their institutional demographics, admissions, and procedure for a 2-year period (1998-1999). RESULTS: A total of 82 trauma centers that provide resident teaching were included. The included centers represent over 247,000 trauma admissions. The majority of trauma centers (65.9%) had > 80% blunt injury. Although all centers performed laparotomies, other results were more variable. For U/S, 24.2% performed none at all and 47.0% performed fewer than two U/S examinations per month. For DPLs, 3.8% performed none and 66.7% performed fewer than two per month. Assuming 1 night of 4 on call, the average surgical resident training at a trauma center performing > 80% blunt trauma has the potential to participate in only 15 trauma laparotomies, 6 diagnostic peritoneal lavages, and 45 ultrasound examinations per year. In addition, the resident will care for an average of 500 blunt trauma patients before performing a splenectomy or liver repair. CONCLUSION: Surgical resident experience on most trauma services is heavily weighted to nonoperative management, with a relatively low number of procedures, little experience with DPL, and highly variable experience with ultrasound. These data have serious implications for resident training and recruitment into the specialty.  相似文献   
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