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991.
We treated 37 infected tibial shaft nonunions by debridement followed by open autogenous cancellous bone grafting in a 2-stage procedure. Additional surgery was done in 21 fractures including second debridement before bone grafting and/or a second limited bone grafting and/or a split-thickness skin grafting. All fractures healed after an average of 11 (8-16) months. During 2 years follow-up there were no recurrences of the infection. Two cases of early refracture occurred, both healed following new bone grafting.  相似文献   
992.
PURPOSE: To analyze the occurrence of subacute and late adverse effects in patients treated with preoperative irradiation for rectal cancer. PATIENTS AND METHODS: The study population included 1,147 patients randomly assigned to preoperative radiation therapy or surgery alone in the Swedish Rectal Cancer Trial conducted 1987 through 1990. Patient data were matched against the Swedish Hospital Discharge Register to identify patients admitted to hospital after the primary treatment of the rectal cancer. Patients with known residual disease were excluded, and patients with a recurrence were censored 3 months before the date of recurrence. Relative risks (RR) with 95% CIs were calculated. RESULTS: Irradiated patients were at increased risk of admissions during the first 6 months from the primary treatment (RR = 1.64; 95% CI, 1.21 to 2.22); these were mainly for gastrointestinal diagnoses. Overall, the two groups showed no difference in the risk of admissions more than 6 months from the primary treatment (RR = 0.95; 95% CI, 0.80 to 1.12). Regarding specific diagnoses, however, RRs were increased for admissions later than 6 months from the primary treatment in irradiated patients for unspecified infections, bowel obstruction, abdominal pain, and nausea. CONCLUSION: Gastrointestinal disorders, resulting in hospital admissions, seem to be the most common adverse effect of short-course preoperative radiation therapy in patients with rectal cancer. Bowel obstruction was the diagnosis of potentially greatest importance, which was more frequent in irradiated than in nonirradiated patients.  相似文献   
993.
Twenty-seven Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines and 27 EBV-carrying Bur-kitt-lymphoma-derived lines were analyzed for expression of the second EBV-encoded nuclear antigen (EBNA-2) by immunoblotting and anticomple-ment immunofluorescence with EBNA-2-specific sera. While all lymphoblastoid cell lines expressed EBNA-2, only 10 of the 27 BL lines were EBNA-2-positive. Comparison of the EBNA-2 coding Bam HI W-Y- and H-fragments of EBV-DNA in the different cell lines by restriction enzyme analysis suggests that EBNA-2 negativity is due either to sequence diversity or to a deletion in the BamHI WYH region.  相似文献   
994.
A case-control study on work with video screen equipment during pregnancy has been made for three cohorts of women, identified with the aid of occupational codes in the census, linked to the Medical Birth Registry and a registry containing information on women hospitalized for spontaneous abortion. Five hundred and twenty-two cases were selected (women with spontaneous abortions or women who had infants that died, had severe malformations, or had a birth-weight below 1,500 g) and 1,032 controls (women who had infants without any of these characteristics) taken from the same age stratum as the cases. All pregnancies had occurred in 1980-81. Questionnaires were mailed to the women asking for information on their work situation, including questions about work with video screen equipment. Fifty-eight women were excluded for various reasons. Response rate was 93%--lower (89%) among women with spontaneous abortions than among women who gave birth (95%). As stress and smoking were associated with video screen work, the effect of video screen work was analyzed after stratification for stress and smoking--no statistically significant effect of video screen work was seen but odds ratios were above 1. Crude odds ratios for video screen work were significantly elevated and showed a dose-dependent effect. This finding is discussed from the point of view of biases in the study: selective non-responding, recall bias, geographical variability, and lack of information on women who had induced abortions. Using questionnaire data for exposure rates in the populations studied, an estimate of the effect greater than or equal to 10 hr weekly work with video screens on spontaneous abortion rate was made. The point estimate was 1.04 with a 95% confidence interval of 0.9-1.2. Analysis of 44 infants with birth defects whose mothers had worked more than 10 hr/week with video screen equipment compared to 30 infants with birth defects whose mothers had not used such equipment in early pregnancy showed no signs of specificity in the type of birth defect.  相似文献   
995.
BACKGROUND: Antipsychotic drugs modulate N-methyl-D-aspartate (NMDA) receptor function in animals. The novel single photon emission tomography (SPET) radiotracer [123I]CNS-1261 binds to the PCP/MK-801 intrachannel site of the NMDA receptor, allowing the noninvasive estimation of NMDA receptor activity in living humans. We used [123I]CNS-1261 to determine whether binding to the NMDA receptor intrachannel PCP/MK-801 site is affected by schizophrenia or by treatment with typical antipsychotics and clozapine in vivo. METHODS: Three groups of schizophrenia patients were recruited-drug free (n = 5), typical antipsychotic treated (n = 7), and clozapine treated (n = 9)-as well as a control group of healthy normal volunteers (n = 13). All underwent [123I]CNS-1261 SPET scanning. Total volume of distribution of [123I]CNS-1261 was determined within predefined user-independent regions of interest after alignment of all images to a common template. RESULTS: There was no apparent difference in total volume of distribution of [123I]CNS-1261 in drug-free patients relative to healthy control subjects. A nonsignificant reduction in total volume of distribution was observed in typical antipsychotic treated patients. A significant decline in total volume of distribution of [123I]CNS-1261 was observed in all examined brain regions in the clozapine-treated patient group relative to healthy control subjects (p < .005). CONCLUSIONS: Clozapine treatment resulted in a global reduction in [123I]CNS-1261 binding to the NMDA receptor intrachannel PCP/MK-801 site in vivo. This supports an effect of the drug on glutamatergic systems that could be exploited for future antipsychotic drug discovery.  相似文献   
996.
997.
Abstract In an earlier study on a selected group of adolescents with high caries prevalence we found dietary habits that resembled those considered to promote the development of atherosclerosis. In the present study we have compared DMF-score with factors traditionally associated with the risk for development cardiovascular diseases (CVD), All 15-yr-olds living in an urban community in Northern Sweden 1987–1989 were included. Medical variables related lo the risk of developing CVD were evaluated in groups of adolescents with various levels of manifest caries expressed as decayed and filled surfaces (DPS). The proportion of individuals with no medical risk factor at an unfavorable level was significantly higher in a caries free than in a high-caries (DFS9) group. Adolescents with two or more medical factors reaching unfavorable levels had a significantly higher caries score than the group with no factor at unfavorable level. A significant positive correlation was found for the whole group between DFS-score and relative body weight (body mass index) in an univariate correlation test as well as multiple linear regression analysis. The hypothesis that high caries score can be an indicator for unfavorable levels of traditional risk factors for CVD is not contradicted by the results in the present study but supported by the observed covariation with BMI. We therefore suggest that dietary counseling to adolescents with a high caries score in combination with a moderate obesity can be of advantage in reducing the caries risk as well as the risk for development of CVD at higher ages.  相似文献   
998.
Abstract In a previous population-based study of 3896 7–9-year-old children living in Sweden, it was found that 32 children (0.8%) exhibited radiographic, periodontal bone loss at 2 proximal surfaces of their deciduous teeth. In the present study, 26 of the 32 children were subjected to additional oral and systemic health examination. 20 other children without any radiographic evidence of bone loss in their primary dentition served as referents. None of the cases or the referents were detected to have any systemic disease. The frequency of bleeding and suppuration on probing, radiographic proximal calculus and probing attachment loss was higher among the cases than the referents. Actinobacillus actinomycetemcomitans was found subgingivally in 14 of the cases but in none of the referents. 11 of 22 cases analysed for presence of serum antibodies against A. actinomycetemcomitans leukotoxin were sero-positive compared to none of 7 referents available for analysis. Evaluation of the data from each child revealed wide variations in clinical parameters among the children in the case group. In this group, there were children with deep probing depths, probing attachment loss, suppuration on probing, proximal calculus and presence of subgingival A. actinomycetemcomitans, indicating current periodontitis. However, in the case group there were also children without positive signs of inflammatory disease, similar to the children in the reference group. In fact, the findings suggest that less than half of the number of individuals with 2 proximal sites with bone loss had current periodontitis.  相似文献   
999.
1000.
Visual disturbances after industrial triethylamine exposure   总被引:6,自引:0,他引:6  
Summary Among 19 workers in a polyurethane foam production plant, visual disturbances (foggy vision, blue haze, and sometimes halo phenomena) were reported on a total of 47 occasions by five workers over 11 weeks. The symptoms were associated with triethylamine exposure. Time-weighted average levels of 12 to 13 mg/m3 were recorded at work operations associated with symptoms, and 4 to 5 mg/m3 at other tasks. Twice as high peak levels were recorded. A detailed medical examination of the five affected workers in a free interval did not reveal any signs of permanent eye disease.  相似文献   
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