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11.
The influence of thoracic extradural local anaesthetics (0.5%bupivacaine) or extradural morphine on the metabolic responseto upper abdominal surgery was compared with the administrationof morphine i.v. in the period after operation. The extradurallocal anaesthetic group had significantly lower blood glucoseand plasma FFA concentrations and consistently, but not significantly,lower blood glycerol and lactate concentrations than both theother groups. At 4 h both extradural groups had significantlylower plasma FFA and blood 3-hydroxybutyrate concentrationsthan the control group. Blood alanine concentration decreasedin all three groups with a minimum at 24 h. There were no differencesin serum insulin concentrations between the groups. It is concludedthat thoracic extradural morphine differs from thoracic extradurallocal anaesthetics in being much less able to suppress the metabolicresponse associated with upper abdominal surgery.  相似文献   
12.
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
13.
Use of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxicity equivalentsconcentration (TEC) assumes that polychlorinated di benzo-p-dioxins(PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) act additivelyand via a common mechanism to cause toxicity. To test theseassumptions, 11 TCDD-like congeners and three non-TCDD-likecongeners were combined at ratios typically found in Lake Michiganlake trout. The potency of the mixture, expressed as TEC basedon fish-specific toxic equivalency factors, was compared toTCDD for producing lake trout and rainbow trout early life stagemortality. Signs of toxicity following exposure of newly fertilizedeggs to the mixture or to TCDD were indistinguishable; sac frymortality associated with blue-sac disease, and slopes of thedose-response curves for percentage sac fry mortality versusegg TEC or versus egg TCDD were parallel. However, the mixturedose-response curves were significantly shifted to the rightof the TCDD dose-response curves by 1.3- to 1.8-fold as illustratedby LD50 values. Following exposure to the mixture or TCDD, LD50sfor lake trout early life stage mortality were 97 (89–110)pg TE/g egg and 74 (70–80) pg TCDD/g (LD50, 95% fiduciallimits) and for rainbow trout were 362 (312–406) pg TE/gegg and 200 (148–237) pg TCDD/g egg. These data suggestthat TCDD-like congeners act via a common mechanism to causetoxicity during trout early development, but may not act strictlyadditively when combined in a mixture of TCDD- and non-TCDD-likecongeners at ratios found in Great Lakes fish. The deviationfrom additivity, however, is less than current safety factorsof 10-fold commonly applied in ecological risk assessments,providing support for the continued use of a TE additivity modelfor assessing risk posed by complex mixtures of PCDDs, PCDFs,and PCBs to fish.  相似文献   
14.

Aims:

To examine the variation in risk factors and hospitalization costs among four elderly dementia cohorts by race and gender.

Materials and Methods:

The 2008 Tennessee Hospital Discharged database was examined. The prevalence, risk factors and cost of inpatient care of dementia were examined for individuals aged 65 years and above, across the four race gender cohorts - white males (WM), black males (BM), white females (WF), and black females (BF).

Results:

3.6% of patients hospitalized in 2008 had dementia. Dementia was higher among females than males, and higher among blacks than whites. Further, BF had higher prevalence of dementia than WF; similarly, BM had a higher prevalence of dementia than WM. Overall, six risk factors were associated with dementia for the entire sample including HTN, DM, CKD, CHF, COPD, and stroke. These risk factors varied slightly in predicting dementia by race and gender. Hospital costs were 14% higher among dementia patients compared to non-dementia patients.

Conclusions:

There exist significant race and gender disparities in prevalence of dementia. A greater degree of co-morbidity, increased duration of hospital stay, and more frequent hospitalizations, may result in a higher cost of inpatient dementia care. Aggressive management of risk factors may subsequently reduce stroke and cost of dementia care, especially in the black population. Race and gender dependent milestones for management of these risk factors should be considered.  相似文献   
15.

Objective

The Health Assessment Questionnaire (HAQ) disability index (DI) is the most common self‐reported measure of physical disability in rheumatoid arthritis (RA). Recently, the HAQ‐II was developed in the US as a short, valid, and reliable alternative using Rasch analysis. Our objective was to compare the scaling properties of the HAQ DI and HAQ‐II in Dutch patients with RA.

Methods

We used data from 472 patients with confirmed RA. Internal construct validity of the HAQ versions was assessed using Rasch analysis. Additionally, external construct validity was assessed by examining correlates with other outcome measures.

Results

The HAQ DI had a large floor effect, with 9.5% of the patients indicating no disability compared with 4.3% for the HAQ‐II. Both versions were unidimensional and adequately fit the Rasch model, containing only 1 nonfitting item. Additionally, 2 HAQ‐II items demonstrated overfit and a high residual correlation, suggesting overlap or redundancy in item content. The HAQ‐II demonstrated better item separation, indicating that it covered a wider range of physical function. Item difficulty estimates were reasonably well spread for the HAQ‐II, whereas the HAQ DI items tended to cluster around similar difficulty levels. Both scales contained several items with differential item functioning by sex, age, or disease duration. Both scales demonstrated the expected pattern of correlations with other outcome measures.

Conclusion

The results indicate that both the HAQ DI and HAQ‐II are psychometrically robust measures of physical function. The Rasch‐developed HAQ‐II, however, has several favorable scaling properties, including a better scale length and a reduced floor effect.  相似文献   
16.
Molecular characterization of human factor XSan Antonio   总被引:1,自引:0,他引:1  
Reddy  SV; Zhou  ZQ; Rao  KJ; Scott  JP; Watzke  H; High  KA; Jagadeeswaran  P 《Blood》1989,74(5):1486-1490
Enzymatic amplification technique was used to isolate all eight exons and sequences around the splice junctions, putative promoter, and polyadenylation sites of human factor X DNA from a patient with factor X deficiency. Two genetic changes in factor X have been observed in this patient. The patient is most likely a compound heterozygote since there is only 14% activity associated with factor X. A point mutation that resulted in the substitution of cysteine (TGC) for arginine (CGC) at amino acid 366 was found in exon VIII of one allele of the factor X gene. This mutation, which occurs in the catalytic domain, can affect the formation of a disulfide bridge and thus could result in a reduction in factor X activity. Sequencing all the regions revealed a second mutation: a deletion of one nucleotide (TCCT to TCT) in exon VII that would cause a frame shift at amino acid 272 followed by termination. We have also shown that the point mutation in exon VIII creates an ApaL1 restriction site and destroys the HinP1 site. Enzymatic DNA amplification followed by restriction digestion provides a quick, reliable, and sensitive method for carrier detection and antenatal diagnosis in affected kindreds. This is the first characterization of factor X deficiency at the molecular level. We propose to name this mutation Factor XSan Antonio.  相似文献   
17.
Kao  KJ; Pizzo  SV; McKee  PA 《Blood》1981,57(3):579-585
A sensitive and precise radioreceptor assay for determining plasma levels of human factor VIII/von Willebrand's factor (FVIII/vWF) has been developed by taking advantage of the FVIII/vWF receptor sites on human platelets. Paraformaldehyde-fixed platelets, which were processed and then stored, retained FVIII/vWF binding activity and therefore could be used as a convenient source of receptors. The human plasma samples to be tested were initially filtered on 4% agarose columns to concentrate the FVIII/vWF protein in the void volume and to remove the factor(s) that interferes with the assay. The percent recovery of FVIII/vWF in the pooled eluent was measured by the recovery of added trace 125I-FVIII/vWF. The coefficients of intra- and interassay variation were 6% and 10%, respectively. The plasma FVIII/vWF concentrations determined by the assay for pooled normal plasma, hemophilia A plasma, and plasmas from two patients with von Willebrand's disease were 16.3 +/- 0.5, 52.6 +/- 1.5, 6.8 +/- 0.8, and 3.2 +/- 0.2 microgram/ml, respectively. The range of plasma FVIII/vWF concentrations varied between 8.3 microgram/ml and 24.9 microgram/ml for 10 normal adults. The plasma FVIII/vWF concentrations determined by the radioreceptor assay correlated well with levels measured by the ristocetin-induced platelet aggregation method, thus demonstrating the functional relevancy of the radioreceptor assay for plasma FVIII/vWF.  相似文献   
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20.
目的探讨蜂胶对糖尿病伤口愈合的作用及其机制。方法采用荧光电泳法,检测不同葡萄糖浓度(5、25mmol/L)和不同蜂胶浓度(10、50、100、200μg/ml)处理的体外培养的人成纤维细胞及单核巨噬细胞系的基质金属蛋白酶MMP-9蛋白的表达。结果高浓度葡萄糖(25mmol/L)状态下,MMP-9表达增加,但与低浓度(5mmol/L)比较,差异无统计学意义。蜂胶可显著降低MMP-9的表达,并呈剂量依赖性(P〈.05)。结论高糖能增加单核巨噬细胞系及成纤维细胞MMP-9的表达,可能会影响糖尿病患者伤口的愈合。蜂胶可抑制这些细胞MMP-9的表达,有益于细胞基质的积聚,从而有益于糖尿病患者伤口的愈合。  相似文献   
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