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21.
22.
The frequency of heterozygous protein C and protein S deficiency, detected by measuring total plasma antigen, in a group (n = 141) of young unrelated patients (less than 45 years old) with venous thrombotic disease was studied and compared to that of antithrombin III, fibrinogen, and plasminogen deficiencies. Among 91 patients not receiving oral anticoagulants, six had low protein S antigen levels and one had a low protein C antigen level. Among 50 patients receiving oral anticoagulant therapy, abnormally low ratios of protein S or C to other vitamin K-dependent factors were presented by one patient for protein S and five for protein C. Thus, heterozygous Type I protein S deficiency appeared in seven of 141 patients (5%) and heterozygous Type I protein C deficiency in six of 141 patients (4%). Eleven of thirteen deficient patients had recurrent venous thrombosis. In this group of 141 patients, 1% had an identifiable fibrinogen abnormality, 2% a plasminogen abnormality, and 3% an antithrombin III deficiency. Thus, among the known plasma protein deficiencies associated with venous thrombosis, protein S and protein C deficiencies (9%) emerge as the leading identifiable associated abnormalities.  相似文献   
23.
Carcinoembryonic antigen (CEA) has been extracted and purified by two different methods from a single aqueous homogenate of liver metastases from a primary adenocarcinoma of the colon, thus enabling direct comparison to be made between a conventional technique using gel filtration and a monoclonal antibody immunoadsorbent method. Yield, immunoreactivity and purity have been determined in both cases by direct weighing, enzyme-linked immunoadsorbent assay, radioimmunoassay and SDS-polyacrylamide gel electrophoresis. Reactivity of the antigen with monoclonal and polyclonal anti-CEA antibodies recognising different epitopes was analysed by Western blotting. There appears to be no significant difference in immunoreactivity or purity by these criteria, but the immunoadsorbent method gave a higher yield of CEA for far less expenditure of time and effort. A variant of CEA with a lower molecular weight was also identified in both preparations.  相似文献   
24.
The effects of candoxatrilat (cis-4-([2-carboxy-3-(2-methoxyethoxy)propyl]-1-cyclopentanecarbonyla mino)- 1-cyclohexane carboxylic acid) and the ring-deleted atrial natriuretic factor (ANF) analogue C-ANF4-23 (des[Gln18, Ser19, Gly20, Leu21, Gly22]ANF4-23-NH2) on the clearance of (3-[125I]iodotyrosyl28)ANF (125I-ANF) were studied in both intact and nephrectomized anaesthetized rats. HPLC analysis was used to verify that the 125I-labelled material isolated by solid phase extraction of rat plasma was intact ANF. In intact animals, clearance of 125I-ANF was biphasic with a T1/2 alpha of 17 sec and T1/2 beta of 95 sec. Volume of distribution (Vd) was 564 mL/kg and plasma clearance (Clp) 248 mL/min/kg. Candoxatrilat, over the dose range 0.01-10 mg/kg i.v., increased T1/2 beta (by a maximum of 56%) and decreased Clp (by up to 52%) with no effect on T1/2 alpha or Vd. C-ANF4-23 (10 micrograms/kg+1 microgram/kg/min i.v.) reduced Vd (by 57%) and Clp (by 54%) with no effect on T1/2 beta, whilst abolishing the T1/2 alpha phase in over 50% of animals. Increasing the dose of C-ANF4-23 did not increase the effect on any of these parameters, apart from a small increase in T1/2 beta. Combining the two agents resulted in a substantial decrease in Clp (76%) whilst the reduction in Vd and increase in T1/2 beta were comparable to those seen with C-ANF4-23 and candoxatrilat alone, respectively. In nephrectomized rats, the pharmacokinetics of 125I-ANF and the changes induced by candoxatrilat were similar to those observed in intact animals, whilst the effects of C-ANF4-23 alone were greater than in intact animals. The combination of C-ANF4-23 and candoxatrilat again produced a substantial increase in T1/2 beta (153%) and decreases in Vd (55%) and Clp (78%) in nephrectomized animals, although these changes could not be distinguished from those seen in intact animals treated with the same combination. Our studies indicate that neutral endopeptidase and ANF-C receptors are both major, and approximately equal, clearance mechanisms for 125I-ANF, together accounting for at least 75% of the total clearance of this peptide in the rat.  相似文献   
25.
The dietary lysine requirement of juvenile hybrid striped bass.   总被引:1,自引:0,他引:1  
Two experiments were conducted to determine the dietary lysine requirement of juvenile hybrid striped bass (Morone saxatilis x M. chrysops). In both experiments the diets contained 35 g crude protein/100 g diet (10 g crude protein supplied by casein and gelatin and 25 g crude protein supplied by crystalline L-amino acids) and contained graded levels of L-lysine.HCl resulting in eight dietary treatments. Diets were fed to triplicate groups of fish and ranged in dietary lysine concentration from 1.2 to 2.6 g/100 g of the dry diet in Experiment 1 and from 0.8 to 2.2 g/100 g of the dry diet in Experiment 2. Weight gain and food efficiency data from Experiment 1 indicated the dietary lysine requirement to be between 1.2 and 1.4 g/100 g of the dry diet. Weight gain, food efficiency and serum lysine data from Experiment 2 confirmed the requirement to be between 1.2 and 1.4 g/100 g of the dry diet. Broken-line analysis of weight gain and food efficiency data from Experiment 2 indicated the dietary lysine requirement to be 1.4 +/- 0.2% of the dry diet, or 4.0 g/100 g of the dietary protein. Changes in the relative proportions of dietary lipid and carbohydrate between the two experiments, although maintaining similar gross energy levels, did not alter the lysine requirement estimate of juvenile hybrid striped bass.  相似文献   
26.
AIMS: To assess the performance of a risk score comprising data routinely available in general practice records (age, gender, body mass index, family history of diabetes, smoking habits and prescribed anti-hypertensive drugs or steroids) in detecting diabetes, impaired glucose tolerance and metabolic syndrome. METHODS: In a population-based, cross-sectional study in a semi-rural general practice in Jutland, Denmark, Cambridge Risk Scores were calculated for 1355 patients without known diabetes (69% response rate) who completed questionnaires and underwent anthropometric measurement and an oral glucose tolerance test. RESULTS: Prevalences of diabetes, impaired glucose tolerance and metabolic syndrome were 2.29% (95% CI: 1.56-3.23), 6.64% (95% CI: 5.38-8.10) and 13.4% (95% CI: 11.5-15.2), respectively. Area under the ROC curve for the risk score and diabetes was 83.8% (75.9-91.7) and for metabolic syndrome [European Group for the Study of Insulin Resistance (EGIR)] was 78.1% (74.6-81.6). Twenty per cent of the population had a risk score above 0.246; at this threshold the sensitivity to detect diabetes was 71.0% (53.4-83.9), the specificity 81.2% (79.0-83.2), positive predictive value 8.1% (6.6-10.0) and likelihood ratio 3.77 (2.94-4.85). For metabolic syndrome (EGIR) corresponding values for sensitivity were 50.3% (43.1-57.5), specificity 84.7% (82.5-85.6), positive predictive value 33.6% (28.2-39.4), and likelihood ratio 3.28 (2.69-4.00). CONCLUSIONS: Undiagnosed hyperglycaemia and metabolic syndrome are common. The Cambridge Risk Score is a practical first step in a screening procedure to identify individuals with these disorders who might benefit from diagnostic testing or to direct preventive interventions.  相似文献   
27.
Using a newly modified dye dilution method for cardiac output determination, we successfully performed frequent serial hemodynamic measurements in newborn dogs to characterize hemodynamic changes in endotoxin shock in neonates. Sixty-seven mongrel newborn dogs (2 to 20 days old, 300 to 1500 gm) were divided into four groups: group 1 (2 to 20 days old, 300 to 1500 gm) received normal saline solution, group 2 (2 to 10 days old, 300 to 800 gm) received 1.5 mg/kg of Escherichia coli lipopolysaccharide (LPS), group 3 (2 to 10 days old, 300 to 800 gm) received 10 mg/kg of LPS, and group 4 (11 to 20 days old, 801 to 1500 gm) received 10 mg/kg of LPS. Cardiac output, heart rate, mean arterial pressure, systemic vascular resistance, and minute work were measured serially after endotoxin administration for 4 hours. Despite extensive manipulation, these measurements were stable in controls throughout the length of the study. Endotoxin, administered at two different doses of 1.5 mg/kg and 10 mg/kg, had profound effects on hemodynamic responses. These effects included a significant dose-related fall in cardiac output, minimal changes in heart rate, and a marked rise in systemic vascular resistance. The hemodynamic changes reported in this study lend additional support to the hypothesis that maturational factors are involved in the hemodynamic response to LPS.  相似文献   
28.
K L Reuter  T Griffin  R E Hunter 《Cancer》1989,63(6):1123-1128
In 35 women with epithelial carcinoma of the ovary, the results of restaging laparotomy were compared with the preoperative abdominopelvic computed tomography (CT) findings to evaluate the accuracy of CT for determining tumor status. In the 36 studies performed, enhanced CT scans at 10-mm to 15-mm intervals had a sensitivity of 84% and a specificity of 88%; in addition, there was 86% agreement between the CT and surgical findings. These results suggest that although CT is not accurate enough to completely replace the restaging laparotomy, its high accuracy in determining residual disease after treatment is helpful for patient management.  相似文献   
29.
Adipose tissue lipogenesis and fat deposition in leaner broiler chickens.   总被引:5,自引:0,他引:5  
Rates of hepatic lipogenesis and secretion of plasma triglyceride-rich lipoproteins in 6- to 7-wk-old broiler chickens were similar to the overall rate of fat deposition in these birds, although approximately 20% of [14C]-labeled VLDL was oxidized to CO2 within 8 h. Only 6-7% of VLDL and portomicron triglyceride was taken up by the abdominal fat pad, but this proportion of total triglyceride flux could account for about 80-85% of the total fatty acids accumulating in that depot. The rate of lipogenesis in adipose tissue was much lower than that in the liver, but it could account for much of the remaining fatty acids. Lipogenesis from [14C]acetate in cultured chicken adipocytes was markedly inhibited by adding VLDL as an exogenous source of fatty acids. However, adipose tissue lipogenesis was not increased in vivo by reduction of plasma lipoprotein flux by genetic selection, by the feeding of a high protein diet or by immunological intervention. The results confirm that adipose tissue lipogenesis makes only a small contribution to adipose tissue growth in normal broilers. Its importance does not increase in response to the reductions in hepatic lipogenesis that accompany genetic or nutritional manipulation of body composition.  相似文献   
30.
The effect of swallowing a small quantity of water or of solid food (biscuit) on the renogram curve was observed in 177 patients. Swallowing provoked contraction of the renal pelvis in 63% of the kidneys with a pelvicalyceal system which was neither obstructed nor dilated, with expulsion of a substantial fraction of the contents within 30 s. This did not occur in obstructed or denervated kidneys, nor in patients with a high transection of the spinal cord. Evidence is adduced that this contraction is mediated reflexly. This effect may be used diagnostically to distinguish physiological dilatation from obstruction. The implications when performing and interpreting renography are discussed. Correspondence to: M.V. Merrick  相似文献   
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