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71.
Objective: In this study our aim was to investigate the efficacy of free tototal PSA ratio in discrimination of benign prostate hyperplasia andprostate cancer.Materials and methods: A total of 194 patients, 52 to 82 years old (mean66.06 ± 0.47 years) with PSA levels between 4 to 20 ng/mL wereincluded into this study. Each patient underwent sextant prostate biopsyunder transrectal ultrasound guidance. The patients were divided into twogroups as PSA 4–10 and 10–20 ng/mL. Patients with benign and malignresults were compared with respect to age, total PSA level, free PSA leveland free/total (f/t) PSA ratio.Results: Biopsies revealed prostate cancer in 16 of 130 patients (12.3%)with serum PSA 4–10 ng/mL and in 10 of 64 patients (15.6%) with serumPSA 10–20 ng/ml. In both PSA groups free PSA and f/t PSA levels werestatistically significant, where total PSA levels were not. In patients with4–20 ng/mL total PSA levels and a cut off level of < 0.18 for f/t PSA, thesensitivity, specificity and positive predictive value for prostate cancerwere 88.5%, 53.6% and 20.4% respectively.Conclusion: Higher levels of PSA suggest prostate cancer, but stilladditional parameters are needed for patients with PSA 4–20 ng/mL, suchas free PSA and f/t PSA. Although a cut off level of < 0.18 for f/t PSA seemsto be the most accurate one to discriminate benign and malign diseasesfurther studies on larger groups of patients are needed.  相似文献   
72.
The Bacillus subtilis rec assay has been specially developed to detect DNA-damaging potential in chemicals, with the rationale based on the relative difference of survival of a DNA repair combination proficient strains and its deficient strain, which is interpreted as genotoxicity. The genotoxic activities of newly (1–6) and previously (7–18) synthesized various benzoxazoles and benzimidazoles were analyzed via the B. subtilis rec assay. Newly obtained benzoxazole and benzimidazole derivatives (1–6) were synthesized in the presence of polyphosphoric acid (PPA) and 6 N HCl, respectively to detect their DNA-damaging activities. Among the tested compounds, 6-methyl-2-(o-chlorophenyl)benzoxazole (9), 5-amino-2-(p-methylbenzyl)benzoxazole (4), 5-(p-fluorobenzamido)-2-phenylbenzoxazole (13), and 2-(p-methylaminophenyl)benzoxazole (18) showed genotoxic activities having Rec50 values of 1.85, 1.74, 1.60, and 1.50 or S-probit values of 0.534, 0.482, 0.460, and 0.357, respectively. On the other hand, 2-(p-bromobenzyl)-5-methylbenzimidazole (6) and 2-benzyl-5-(p-fluorophenylacetamido)-benzoxazole (15) were exhibited a reverse effect that displayed a bacterial growth in the rec - strains while there was no any bacterial growth in rec + strains at the same concentration.  相似文献   
73.
OBJECTIVE: To determine the effects of the 1983 law that legalized induced abortion on the number and place of abortions, and on the use of family planning (FP) methods before and after abortion, and to determine the demographic characteristics and reproductive health features according to the order of abortion. METHOD: This study included 2455 married, widowed or divorced women presenting at Mother and Child Health-Family Planning Centres in Ankara. A questionnaire was used for data collection. RESULT: Nearly three out of 10 (28.7%) of the women had undergone at least one induced abortion. In the age groups 45-54 and 55-64, 49 and 37.3%, respectively, had had one or more terminations of pregnancy (TOPs). The induced abortion rate increased following the enacting of the law. In the 15-24 and in the 55-64 age group, 55.6 and 89%, respectively, of the women had been aborted by a private physician. Before the index pregnancy, 63.1% were not using contraception compared with 37.3% thereafter. The rate of use of FP increased after the law was passed. CONCLUSION: Although the most common reason for having an abortion was unwanted pregnancy in all age groups and nearly 60.0% of the women aged less than 55 reported that they were not using any FP method at the time of the TOP, the proportion of women having undergone at least one of these procedures increased after the law was passed, indicating that abortion is used as a FP method.  相似文献   
74.
75.
OBJECTIVE: To examine the contribution of genetic and environmental factors to disease occurrence in 26 families with two or more members affected with systemic lupus erythematosus (SLE). METHODS: Genetic and environmental factors were examined by HLA-A, B, C/DR typing and by determining the presence of lymphocytotoxic antibodies (LCA) in patients and their consanguineous and non-consanguineous relatives. RESULTS: No association between SLE and HLA-A, B, C antigens was found. There was, however, a significant association with HLA-DR2 in white subjects with SLE. The most striking finding was that HLA sharing was increased among the affected members, suggesting genetic similarities. Seven of 14 sib pairs (50%) who had concordant SLE were HLA identical as opposed to an expected 25%. Another interesting finding was that 15/18 (83%) patients with SLE and 11/22 (50%) consanguineous relatives had LCA, while 1/9 (11%) spouses, and 2/42 (5%) healthy controls had these antibodies. CONCLUSION: Genetic factors have a role in the development and expression of SLE. Environmental factors may trigger the disease in genetically susceptible hosts.  相似文献   
76.
The presence of extended spectrum beta-lactamases (ESbetaLs) in 129 Escherichia coli and 128 Klebsiella pneumoniae strains was determined with the E test. beta-lactamases were detected in 66 (51.2%) of E.coli and 107 (83.6%) of K. pneumoniae by the nitrocefin disk method. Putative ESbetaL production was observed in 15.5% of E. coli and 55.5% of K. pneumoniae with the E test. Among the putative ESbetaL-producer strains 11 were found to be susceptible to ceftizoxime, 6 to ceftazidime, 2 to ceftriaxone, cefotaxime and aztreonam, and one to cefoperazone according to the disk diffusion test. All putative ESbetaL-producers were resistant to cefodizime, thus it may be a good indicator of the presence of mainly TEM-type ESbetaL. The E test was also found to be practicable for the detection of ESbetaLs in clinical laboratory. Further studies are needed to clarify whether ESbetaL can be identified reliably in species that, in addition to plasmid mediated ESbetaL production, chromosomally encoded AmpC beta-lactamases and other class A ESbetaLs by disk diffusion test.  相似文献   
77.
Objective: Cigarette smoking is one of the major risk factors for coronary artery disease. However, chronic smoking has additional cardiac adverse effects independent of coronary atherosclerosis. We assessed the possible effects of chronic smoking on left and right ventricular (LV, RV) long-axis function using Doppler myocardial imaging (DMI). Methods: Forty otherwise healthy smokers (mean age = 26 ± 3 years) and 40 age-matched nonsmoking controls enrolled. Standard echocardiography protocol was followed by DMI. Peak systolic (VS), early (VE) and late diastolic (VA) velocities, peak systolic strain (S), and strain rate (SR) were measured from septal, lateral, and RV free walls. Results: The baseline characteristics of two groups were similar. There were significant differences regarding Doppler myocardial velocity, S, and SR indices. Septal VE (P < 0.04), S (P < 0.0001) and SR (P < 0.02) were significantly reduced in smokers. For both lateral and RV free wall, VS (P < 0.003, P < 0.002, respectively), VE (P < 0.0001, P < 0.002, respectively), S (P < 0.0001 for both), and SR (P < 0.0001, P < 0.002, respectively) were significantly reduced in smokers. There were significant correlations between the amount of smoking and septal, lateral, and RV free wall S and SR. Conclusions: Chronic cigarette smoking causes alterations in long-axis systolic and diastolic functions of right and left ventricles in healthy young subjects. These changes can be accurately detected with Doppler myocardial velocity and SR imaging.  相似文献   
78.
OBJECTIVE: The aim of this study was to investigate the nutritional status of children on continuous ambulatory peritoneal dialysis (CAPD) and to relate it to the dose of dialysis and serum levels of inflammatory cytokines and insulin-like growth factor-1 (IGF-1). PATIENTS: 17 CAPD patients (8 girls, 9 boys; mean age 13.1 +/- 3.5 years, median 15 years) were included in the study. Anthropometric measurements and serum albumin levels were used in the evaluation of nutritional status. Serum interleukin (IL)-1beta, IL-6, tumor necrosis factor alpha, and IGF-1 levels were determined in all CAPD patients and in a healthy control group. Weekly Kt/V and creatinine clearance (CCr) were measured to determine adequacy of dialysis. RESULTS: The mean dialysis period was 23.7 +/- 15.2 months (median 23 months). Anthropometric measurements and serum albumin level were as follows: height 130.2 +/- 15.6 cm, height standard deviation score (HtSDS) -4.2 +/- 2.4, body mass index (BMI) 16.3 +/- 1.6 kg/m2, body mass index standard deviation score (BMISDS) -0.8 +/- 0.9, triceps skinfold thickness (TST) 4.2 +/- 1.4 mm, midarm circumference (MAC) 16.21 +/- 2.3 cm, upper arm muscle area (AMA) 1799.1 +/- 535.7 mm2, upper arm fat area (AFA) 334.5 +/- 143 mm2, and serum albumin 3.1 +/- 0.7 g/dL. The BMI was above the fifth percentile in all patients; TST and MAC were below the fifth percentile in 14 patients (82.4%) and 10 patients (58.8%) respectively. The AMA was below the fifth percentile in 8 patients; however, the AFA was below the fifth percentile in all patients. Mean serum albumin level was under 3.5 g/dL in 70.5% of the children. We found significant positive correlations between BMI and Kt/V (r = 0.69, p < 0.01), CCr (r = 0.64, p < 0.05), and IL-6 (r = 0.61, p < 0.01). There was an inverse correlation between BMISDS and dialysis period (r = -0.58, p < 0.05); and between IL-6 and serum albumin (r = -0.49, p < 0.05). A significant positive correlation between BMISDS and serum IGF-1 level (r = 0.62, p < 0.01) was noted. We also found a significant positive correlation between serum IGF-1 level and both HtSDS (r = 0.57, p < 0.05) and TST (r = 0.52, p < 0.05). Significant positive correlations between AFA and CCr and IGF-1 were also noted (both r = 0.56, p < 0.05). CONCLUSION: Although many factors may be responsible for malnutrition and growth retardation, we found that prolonged period of dialysis, inadequate dialysis, and low IGF-1 levels are the most important risk factors in CAPD patients.  相似文献   
79.
OBJECTIVE: Portomesenteric venous gas is a rare condition with an unclear pathogenesis. Most studies in the medical literature mention computed tomography (CT) as the primary imaging tool for this entity. The objective of this study was to outline the advantages and disadvantages of sonography in the evaluation of patients with portomesenteric venous gas. METHODS: We describe 7 patients (3 female and 4 male; age range, 47-83 years) with portomesenteric venous gas. Both CT and sonographic examinations were performed in each patient. Our patient population consisted of 2 patients with superior mesenteric artery occlusion, 3 with ischemia of the colon, small bowel, or both, 1 with gastric ulcer perforation, and 1 with ischemic bowel disease presumably secondary to complications of continuous ambulatory peritoneal dialysis. RESULTS: Portal venous gas was observed in all 7 patients with sonography and in 6 patients with CT. Computed tomography was unable to show gas in the portal venous system in 1 patient. Sonography showed patchy hepatic gas accumulation (likely within small peripheral portal vein branches) with no correlative findings on CT. Computed tomography showed important associated findings, including pneumatosis intestinalis. CONCLUSIONS: In cases with portomesenteric gas, CT is the preferred modality for showing the underlying etiology. However, with its real-time imaging capability, sonography may also be a very valuable imaging modality in the evaluation of this entity.  相似文献   
80.
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