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41.
The purpose of this study was to examine the effects of the Picture Exchange Communication System (PECS) on the spontaneous communication skills of a 6-year-old girl with autism across her home and school environments. The effects of the PECS were also examined for social interaction. Results indicated increases in spontaneous language (i.e., requests and comments) including use of the icons and verbalizations across those settings in which PECS was implemented. Intelligible verbalizations increased in two of three settings, and changes in peer social interaction were noted in one of the two school settings.  相似文献   
42.
OBJECTIVE: Two alcohol dehydrogenase genes (ADH2 and ADH3 on chromosome 4) and one aldehyde dehydrogenase gene (ALDH2 on chromosome 12) exhibit functional polymorphisms. The goal of this study was to determine whether any associations exist between the ADH2, ADH3, and ALDH2 polymorphisms and alcohol dependence in a group of Native Americans. An additional goal was to determine if any associations exist between these polymorphisms and the endophenotype, maximum number of drinks ever consumed in a 24-hour period. METHOD: Mission Indian adults (N=340) were recruited for participation from reservations in southern California. Each participant completed an interview with the Semi-Structured Assessment for the Genetics of Alcoholism. A blood sample was collected from each participant for genotyping at the ALDH2, ADH2, and ADH3 loci. RESULTS: Sixty percent of all participants (72% of men and 53% of women) met lifetime DSM-III-R criteria for alcohol dependence. A significant difference in the ADH2 allele distributions was found between alcohol-dependent and non-alcohol-dependent participants. Those with alcohol dependence were significantly less likely to have the ADH2*3 allele (odds ratio=0.28) and significantly more likely to have the ADH2*1 allele (odds ratio=2.00) than those who were not alcohol dependent. Individuals with ADH2*3 reported a lower number of maximum drinks ever consumed in a 24-hour period, compared to those without this allele. CONCLUSIONS: These results are consistent with genetic linkage studies showing protective associations for alcohol dependence and related behavior on chromosome 4 and suggest that ADH2 polymorphisms may account for these findings. These results also highlight the utility of evaluating protective factors in populations with high rates of alcohol dependence.  相似文献   
43.
BACKGROUND: Dietary surveys suggest that many older, community-dwelling adults consume insufficient dietary protein, which may contribute to the age-related loss of lean mass (LM). OBJECTIVE: The objective of the study was to determine the association between dietary protein and changes in total LM and nonbone appendicular LM (aLM) in older, community-dwelling men and women. DESIGN: Dietary protein intake was assessed by using an interviewer-administered 108-item food-frequency questionnaire in men and women aged 70-79 y who were participating in the Health, Aging, and Body Composition study (n=2066). Changes in LM and aLM over 3 y were measured by using dual-energy X-ray absorptiometry. The association between protein intake and 3-y changes in LM and aLM was examined by using multiple linear regression analysis adjusted for potential confounders. RESULTS: After adjustment for potential confounders, energy-adjusted protein intake was associated with 3-y changes in LM [beta (SE): 8.76 (3.00), P=0.004] and aLM [beta (SE): 5.31 (1.64), P=0.001]. Participants in the highest quintile of protein intake lost approximately 40% less LM and aLM than did those in the lowest quintile of protein intake (x+/-SE: -0.501+/-0.106 kg compared with -0.883+/-0.104 kg for LM; -0.400+/-0.058 kg compared with -0.661+/-0.057 kg for aLM; P for trend<0.01). The associations were attenuated slightly after adjustment for change in fat mass, but the results remained significant. CONCLUSION: Dietary protein may be a modifiable risk factor for sarcopenia in older adults and should be studied further to determine its effects on preserving LM in this population.  相似文献   
44.
BACKGROUND: Many older adults desire to lose weight, yet the proportion with a health-related weight-loss indication, weight-loss strategies, and success is unknown. OBJECTIVE: We examined the associations of reported intention to lose weight with health-related indications for weight loss, diet quality, physical activity, and weight-loss success in well-functioning older adults. DESIGN: This prospective, community-based cohort included 2708 elderly persons aged 70-79 y at baseline. We determined indication for weight loss by using the modified National Institutes of Health guidelines, diet quality by using the Healthy Eating Index, and weight-loss intention and physical activity by using questionnaires. Measured weight change over 1 y was assessed. RESULTS: Twenty-seven percent of participants reported an intention to lose weight, and 67% of those participants had an indication for weight loss. Participants who reported a weight-loss intention were heavier than those who did not, had more depressive symptoms, and were more likely to be dissatisfied with their weight, regardless of weight-loss indication. Participants with an intention to lose weight reported better eating behaviors and a more active lifestyle than did participants without a weight-loss intention, independent of other health conditions. No significant difference in actual weight loss was found between participants intending and not intending to lose weight, regardless of indication for weight loss. CONCLUSIONS: Despite being associated with healthier behaviors, the intention to lose weight did not predict greater weight loss in this well-functioning elderly cohort. More attention needs to be focused on the necessity and efficacy of specific strategies for weight loss in older adults.  相似文献   
45.
The assessment of immunogenicity of a diluted vaccinia vaccine for possible widespread use of a diluted vaccine in the event of a bioterrorist attack prompted us to focus on the development of a sensitive and specific plaque reduction neutralization (PRN) assay to assess the antibody response of volunteers to a vaccinia (Dryvax) vaccine. Two incubation times, 1 h or overnight (approximately 15 h), were explored for the neutralization step of the assay. In addition, serum samples were evaluated using both sonicated and nonsonicated virus in PRN assays with 1 and 15 h of incubation. The use of the overnight incubation method resulted in the detection of antibody in two vaccinated individuals who exhibited a take, i.e., a major reaction indicative of successive vaccination as defined by the Centers for Disease Control and Prevention, but did not have a fourfold increase in antibody to vaccinia virus by the 1-h-incubation method and increased the sensitivity from 94 to 100%. In addition to the increased sensitivity of the assay, we noted a significant increase (approximately 40-fold) in the PRN titer of serum samples tested with the 15-h-incubation method. The use of sonicated virus increased the reproducibility of the virus titers and PRN titers. Forty-two percent of the samples tested using sonicated virus had a PRN titer that was fourfold higher or greater than that of nonsonicated virus in the assay. A PRN titer that was threefold higher or greater was observed in more than half (58%) of the samples using sonicated virus. Therefore, the more sensitive, specific, and reproducible plaque neutralization assay for the detection of antibody to vaccinia virus is the method using a 15-h-incubation time and freshly sonicated vaccinia virus.  相似文献   
46.
The objective of this study was to evaluate the ability of bladder acellular matrix (BAM) to support the individual and combined growth of primary porcine bladder smooth muscle (SMC) and urothelial (UEC) cells. An in vitro co-culture system was devised to evaluate the effect of UEC on (i) SMC-mediated contraction of BAM discs, and (ii) SMC invasiveness into BAM. Cells were seeded onto BAM discs under 4 different culture conditions. Constructs were incubated for 1, 7, 14 and 28 days. Samples were then harvested for evaluation of matrix contraction. Immunohistochemistry (IHC) was utilized to examine cellular organization within the samples and conditioned media supernatants analyzed for net gelatinase activity. BAM contraction was significantly increased with co-culture. The same side co-culture configuration lead to a greater reduction in surface area than opposite side co-culture. IHC revealed enhanced SMC infiltration into BAM when co-culture was utilized. A significant increase in net gelatinase activity was also observed with the co-culture configuration. Enhanced infiltration and contractile ability of bladder SMCs with UEC co-culture may, in part, be due to an increase in gelatinase activity. The influence of bladder UECs on SMC behaviour in vitro indicates that BAM may contain some key inductive factors that serve to promote important bladder cell-cell and cell-matrix interactions.  相似文献   
47.
A novel PPAR response element in the murine iNOS promoter   总被引:6,自引:0,他引:6  
  相似文献   
48.
Pluripotent embryonic stem (ES) cells have emerged as a powerful tool for disease modeling and neural regeneration. Transplantation studies in rodents indicate that ES cell-derived glial precursors (ESGPs) efficiently restore myelin in dysmyelinating mutants and chemically induced foci of myelin loss. Here we explore the myelination potential of ESGPs in an antibody/complement-induced demyelination model. Microinjection of an antibody to myelin oligodendrocyte glycoprotein (MOG) and complement was employed to generate circumscribed areas of demyelination in the adult rat spinal cord. ESGPs transplanted into 2-day-old lesions were found to survive and differentiate into both oligodendrocytes and astrocytes. The engrafted cells remained largely confined to the lesion site and showed no evidence of tumor formation up until 4 weeks after transplantation. Within areas of pronounced microglial activation and macrophage extravasation, engrafted ES cell-derived oligodendrocytes contacted and enwrapped host axons and alongside endogenous glia, contributed to the formation of new myelin sheaths. These findings demonstrate that ESGPs transplanted into acutely demyelinated lesions can contribute to myelin repair.  相似文献   
49.
Analyses of natural feeding behavior in albino male Sprague-Dawley rats demonstrate that, when allowed to self-select from pure macronutrient diets (protein, carbohydrate and fat), these rats of the same genetic strain can be categorized into 3 subpopulations according to either their 24-h or their 12-h nocturnal patterns of nutrient intake. A majority of the animals (HC for high carbohydrate, 50% of the total population) consumed a diet rich in carbohydrate relative to protein or fat, while a smaller population of rats (HF, 30%) preferred the fat diet, and an even smaller population (HP, 20%) chose a high-protein diet. These 3 subpopulations, after a few weeks of maintenance on the diets, differed in their body weight, with the HF rats having a higher body weight than the HP animals, who tended to weigh more than the lightest HC rats. Whereas all subgroups exhibited a similar bimodal distribution of feeding during the nocturnal cycle, with peaks during the early and late dark periods, they were distinguishable on the basis of their nutrient consumption during specific phases of the dark cycle. This difference was most apparent in the early dark phase, when the 3 subgroups exhibited exaggerated preferences for the specific nutrient that was generally preferred over the 24-h cycle. This is in contrast to the middle dark phase, when diet preferences were attenuated or lost, and the late dark phase, when most rats were similar in showing an increased preference for protein and fat and a decreased preference for carbohydrate. The HF group was further distinguished by an unusually strong burst of feeding during the first 2 h of the dark period and an extra peak of feeding in the middle dark period (7th h), both of which were relatively high in fat content.  相似文献   
50.
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