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With the spread of gambling in its many forms across the American landscape the question arises as to how senior citizens have been effected. This study examines data on gambling behavior and related attitudes gathered from a random sample of community residents in jurisdictions that had recently allowed casinos to open. Comparisons are made between senior and younger adults regarding their gambling behaviors. Though the results suggest that casino gambling is not a major threat to the elderly it is noted that more extensive research needs to be done to assess the individual and social costs and benefits, if any, associated with large numbers of the elderly regularly participating in gambling as a social activity.  相似文献   
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Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.  相似文献   
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The relationship between homovanillic acid (HVA), vanillylmandelic acid (VMA), and creatinine in the urine of 6 month old babies has been studied and reference ranges in the form of centiles constructed for HVA and VMA against creatinine. Over 10,000 urine samples were collected from babies in four health districts in the north of England. HVA and VMA concentration, either independently or when divided by creatinine concentration, were dependent upon the absolute concentration of creatinine in the sample. After adjustment for creatinine significant differences in the mean concentration of HVA were found between sexes. No such differences were found for VMA. HVA and VMA were also found to be age dependent. Centiles were constructed using a procedure which makes no distributional assumptions about the data. The net effect of utilising these centiles was to increase the predictive value of a positive screening test from 20% to 40% without any increase in the false negative rate.  相似文献   
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PURPOSE: Three-dimensional conformal radiation therapy requires the precise definition of the target volume. Its potential benefits could be offset by the inconsistency in target definition by radiation oncologists. In a previous survey of radiation oncologists, a large degree of variation in target volume definition of cervical esophageal cancer was noted for the boost phase of radiotherapy. The present study evaluated whether special training could improve the consistency in target volume definitions. METHODS AND MATERIALS: A pre-training survey was performed to establish baseline values. This was followed by a special one-on-one training session on treatment planning based on the RTOG 94-05 protocol to 12 radiation oncologists. Target volumes were redrawn immediately and at 1-2 months later. Post-training vs. pre-training target volumes were compared. RESULTS: There was less variability in the longitudinal positions of the target volumes post-training compared to pre-training (p < 0.05 in 5 of 6 comparisons). One case had more variability due to the lack of a visible gross tumor on CT scans. Transverse contours of target volumes did not show any significant difference pre- or post-training. CONCLUSION: For cervical esophageal cancer, this study suggests that special training on protocol guidelines may improve consistency in target volume definition. Explicit protocol directions are required for situations where the gross tumor is not easily visible on CT scans. This may be particularly important for multicenter clinical trials, to reduce the occurrences of protocol violations.  相似文献   
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BACKGROUND: We report survival and pretreatment prognostic factors for survival and chemosensitivity in 53 oligodendrogliomas treated with PCV (procarbazine, lomustine and vincristine) chemotherapy. METHODS: A total of 53 patients with histologically proven oligodendroglioma, anaplastic oligodendroglioma or oligo-astrocytoma and treated with PCV were extracted from the London Regional Cancer Center database. A retrospective review was conducted to evaluate overall survival and pretreatment prognostic factors for survival and chemosensitivity. RESULTS: The median survival time from diagnosis was 123.6 months. The overall five- and ten-year survival rates were 72.7% and 52.7% respectively. Age <40, seizure as an initial symptom, absence of cognitive deficit and presence of a homogeneous hypodense lesion without contrast enhancement on the initial pretreatment CT scan were all factors independently associated with favorable outcome. The presence of increased cellularity, pleomorphism, mitosis, vascular proliferation and grading as an anaplastic lesion using these surrogates on pathological assessment, were all associated with an unfavorable outcome in univariable analysis. In multivariable analysis, only the anaplastic grading and presence of increased cellularity were significant determinants of unfavorable survival. The only factor adversely associated with chemosensitivity was the presence of a focal symptom at presentation. CONCLUSION: Overall survival is significantly longer in oligodendroglial lesions than in fibrillary astrocytic tumors. A two tier grading system using standard morphological features seems accurate in predicting outcome in these patients. The presence of a neoplastic astrocytic component does not seem to impact the outcome. No clinical, radiological or pathological factor could be identified to reliably predict chemotherapy response.  相似文献   
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BACKGROUND: Several studies have reported the incidence, morbidity, and mortality of general surgical conditions (GSCs) in orthotopic heart transplant (OHT) patients. The following is the largest reported series of such patients and the first study with sufficient patient numbers to formally evaluate peritransplant variables as risk factors for GSC development. STUDY DESIGN: A GSC was defined as a condition for which a general surgeon had been consulted or as a general surgical condition recognized at the time of autopsy. The records of 453 consecutive patients who underwent OHT between 1981 and 1999 were reviewed to identify patients who developed a GSC. Kaplan-Meier actuarial analysis on this cohort, and univariate and multivariate logistic regression models applied to a subpopulation of 324 consecutive OHT patients between 1987 and 1997 were used to determine factors associated with and predictive of GSC after OHT. RESULTS: Of 453 OHT patients, 371 (81.9%) were men, and the average age was 44.5 +/- 15 (standard deviation) years. Median followup was 2,086 days (range 1 to 6,642 days). Ninety-three patients (20.5%) developed 111 GSCs. Of these, 78 were men, and the average age was 49.9+/-10.2 years. There were 83 general surgical interventions. Actuarial analyses revealed that age greater than 50 years, pretransplant diagnosis of ischemic (PTDxI) versus nonischemic heart disease, and previous general surgical history were factors associated (p < 0.05) with a higher GSC incidence. Gender, more urgent transplant priority status, cardiopulmonary bypass time, total graft ischemic time, and intensive care unit length of stay were not associated with GSC. Factors associated with GSC on univariate analysis, with odds ratios (ORs) and 95% confidence intervals (CIs) included: age analyzed as a continuous variable (OR 1.04 per year; CI 1.01, 1.06 per year; p = 0.0021), PTDxI (OR 2.40; CI 1.39, 4.15; p = 0.0016), and pretransplant general surgical history (OR 3.35; CI 1.65, 6.82; p = 0.0008). Multivariate analysis revealed that only pretransplant general surgical history (OR 3.27; CI 1.58, 6.76; p = 0.0004) and PTDxI (OR 2.37; CI 1.35, 4.16; p = 0.0023) were associated with subsequent development of GSC. CONCLUSIONS: A pretransplant diagnosis of ischemic heart disease and previous history of a general surgical procedure are two independent risk factors that predispose OHT patients to development of GSC. Because GSC may arise insidiously in immunosuppressed patients, identification of OHT patients at higher risk for GSC will permit timely intervention decisions, decreasing morbidity and mortality in this challenging group of patients.  相似文献   
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Background

The identification of live cells using membrane integrity dyes has become a frequently used technique, especially with articular cartilage and chondrocytes in situ where tissue slices are used to assess cell recovery as a function of location. The development of a reproducible computerised method of cell evaluation would eliminate many variables associated with manual counting and significantly reduce the amount of time required to evaluate experimental results.

Methods

To validate a custom computerised counting program, intra-person and inter-person cell counts of nine human evaluators (three groups – unskilled, novice, and experienced) were compared with repeated pixel counts of the custom program on 15 digitised images (in triplicate) of chondrocytes in situ stained with fluorescent dyes.

Results

Results indicated increased reproducibility with increased experience within evaluators [Intraclass Correlation Coefficient (ICC) range = 0.67 (unskilled) to 0.99 (experienced)] and between evaluators [ICC = 0.47 (unskilled), 0.85 (novice), 0.93 (experienced)]. The computer program had perfect reproducibility (ICC = 1.0). There was a significant relationship between the average of the experienced evaluators results and the custom program results (ICC = 0.77).

Conclusions

This study demonstrated that increased experience in cell counting resulted in increased reproducibility both within and between human evaluators but confirmed that the computer program was the most reproducible. There was a good correlation between the intact cell recovery determined by the computer program and the experienced human evaluators. The results of this study showed that the computer counting program was a reproducible tool to evaluate intact cell recovery after use of membrane integrity dyes on chondrocytes in situ. This and the significant decrease in the time used to count the cells by the computer program advocate its use in future studies because it has significant advantages.
  相似文献   
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