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131.
Streptokinase has been immobilized by covalent coupling to nylon. Subcutaneous implantation of the immobilized streptokinase into rabbits resulted in a three-fold increase in their blood clotting time, which was maintained for 150 days. The immobilized streptokinase lost little if any activity over this period and no evidence of antibody formation was found. Removal of the implanted nylon-streptokinase caused a return to normal clotting times within a few days. The preliminary results demonstrate a potential usefulness of immobilized streptokinase in the treatment of thrombotic occlusive disorders as well as in the prevention of such diseases.  相似文献   
132.
A comparison of the effects of extracellular and intracellular thirst stimuli on plasma levels of angiotensin II was made in rats. The administration of polyethylene glycol and isoproterenol elicited a strong drinking response and resulted in a significant increase in plasma angiotensin II. There was a significant correlation between the volume of water intake and plasma angiotensin II levels following the injection of polyethylene glycol but not following isoproterenol. Drinking was also elicited by the administration of hypertonic saline but there was no increase in plasma angiotensin II. The results suggest that endogenously released angiotensin II contributes to extracellular thirst but not to intracellular thirst.  相似文献   
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OBJECTIVE: The purpose of this study was to evaluate the relationship between prepregnancy maternal body mass index and spontaneous preterm birth and indicated preterm birth. STUDY DESIGN: This was a secondary analysis of the Maternal-Fetal Medicine Units Network, Preterm Prediction study. Patients were classified into categories that were based on their body mass index. Rates of indicated and spontaneous preterm birth were compared. RESULTS: Five hundred ninety-seven (20.5%) of 2910 women were obese. Obese women had fewer spontaneous preterm births at < 37 weeks of gestation (6.2% vs 11.2%; P < .001) and at < 34 weeks of gestation (1.5% vs 3.5%; P = .012). Women with a body mass index of < 19 kg/m2 had 16.6% spontaneous preterm birth, with a body mass index of 19 to 24.9 kg/m 2 had 11.3% spontaneous preterm birth, with a body mass index of 25 to 29.9 kg/m2 had 8.1% spontaneous preterm birth, with a body mass index of 30 to 34.9 kg/m2 had 7.1% spontaneous preterm birth, and with a body mass index of > or = 35 kg/m2 had 5.2% spontaneous preterm birth (P < .0001). Indicated delivery was responsible for an increasing proportion of preterm births with increasing body mass index (P = .001). Obese women had lower rates of cervical length < 25 mm (5% vs 8%; P = .012). Multivariable regression analysis confirmed a lower rate of spontaneous preterm birth in obese gravid women (odds ratio, 0.57; 95% CI, 0.39-0.83; P = .003). CONCLUSION: Obesity before pregnancy is associated with a lower rate of spontaneous preterm birth.  相似文献   
136.
Optimal athletic performance depends on proper function of many organs, including the blood. This is underscored by the focus of endurance athletes on increased hemoglobin through training at altitude or exogenous erythropoietin. Several other aspects of the hematologic system can also affect or be influenced by physical activity. In this article, the authors briefly discuss inherited abnormalities of the blood that can manifest themselves in athletes. We then discuss the effects of exercise on the blood, and acquired abnormalities of blood cells or coagulation parameters that occur in athletes, and that can influence performance or cause other symptoms.  相似文献   
137.
BACKGROUND: Perioperative homologous blood transfusion (HBT) is associated with adverse reactions and risks transmission of infection. It has also been implicated as an immunosuppressive agent. Intraoperative autotransfusion (IAT) is a potential method of autologous transfusion. METHODS: This was a single-centre randomized clinical trial of IAT in surgery for abdominal aortic aneurysm. Forty patients were randomized to IAT and 41 underwent surgery with HBT only. Patients in both groups received HBT to maintain haemoglobin levels above 8 g/dl. Transfusion requirements, and incidence of systemic inflammatory response syndrome (SIRS) and infection, were compared. RESULTS: Significantly fewer patients in the IAT group required HBT (21 versus 31; P = 0.038) and the median blood requirement per patient was 2 units lower (P = 0.012). There was a higher incidence of chest infection (12 versus four patients; P = 0.049) and SIRS (20 versus nine patients; P = 0.020) in the HBT group. Risk of SIRS was related to aortic cross-clamp time in the IAT group only. CONCLUSION: Use of autotransfusion effectively reduced the need for HBT and was associated with a reduced incidence of postoperative SIRS and infective complications.  相似文献   
138.
Urological manifestations of Down syndrome   总被引:1,自引:0,他引:1  
PURPOSE: We identified the urological anomalies seen in patients with Down syndrome. MATERIALS AND METHODS: We reviewed the literature on Down syndrome and its associated genitourinary pathology. RESULTS: Associated defects have been reported throughout the genitourinary tract. The most common renal anomalies seen are renal hypoplasia, obstructive uropathy and glomerular microcysts. Decreased creatinine clearance has also been noted. Developmental anomalies, such as megaureter and vesicoureteral reflux, have been reported. Dysfunctional voiding and urinary retention have been found in these patients. Posterior urethral valves and hypospadias have also been seen. The testicular abnormalities most frequently reported are cryptorchidism, testicular cancer and infertility. CONCLUSIONS: Improved understanding and identification of the various urological anomalies associated with Down syndrome will aid in the care of these patients. In addition, an awareness of perioperative issues will further facilitate a smooth clinical course.  相似文献   
139.
An antibody directed at the carboxy tail of the cholecystokinin-1 receptor (CCK1R) was characterized by ELISA and Western blotting. Immunohistochemistry established that CCK1R-like immunoreactivity (CCK1R-LI) was widely and topographically distributed through the neuroaxis, appearing relatively higher in rhi- and diencephalon, and intense in both neuronal somata (cytoplasmic) and processes. CCK1R-LI was found in new loci, but also in areas previously identified by receptor autoradiography, electrophysiology and in situ hybridization of CCK1R mRNA. The widespread distribution of CCK1R has implications for the functional roles of these receptors in brain. The high titre and low background seen with this new antiserum makes it of great value for cell and tissue research.  相似文献   
140.
This study examined the effects of indoor gardening on socialization, activities of daily living (ADLs), and perceptions of loneliness in elderly nursing home residents. A total of 66 residents from two nursing homes participated in this two-phase study. In phase one, experimental group 1 participated once a week for 5 weeks in gardening activities while a control group received a 20-minute visit. While no significant differences were found between groups in socialization or perceptions of loneliness, there were significant pretest-posttest differences within groups on loneliness and guidance, reassurance of worth, social integration, and reliable alliance. The results also demonstrated gardening interventions had a significant effect on three ADLs (transfer, eating, and toileting). Phase two examined differences in the effects of a 5-week versus a 2-week intervention program. Although no significant within-group differences were noted in socialization, loneliness, or ADLs, the 5-week program was more effective in increasing socialization and physical functioning.  相似文献   
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