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Background. Vitiligo is an acquired skin disorder that is characterized by well-defined, often symmetric white patches. Although current therapeutic modalities are directed toward increasing melanocyte melanin production, few treatment modalities address the immunologic nature of the disease.
Objective. To determine whether excimer laser, a known therapeutic modality, in combination with tacrolimus, a topical immunomodulator, accelerate response time and/or improve the degree of response in patients with this disorder.
Methods. Eight subjects diagnosed with vitiligo were recruited to participate in this institutional review board–approved double-blind, placebo-controlled study. Twenty-four symmetric vitiliginous patches (elbows, knees) from eight subjects received excimer laser treatment three times per week for 24 treatments or 10 weeks. Additionally, topical tacrolimus 0.1% ointment (Protopic) and placebo (Aquaphor) were applied to randomized patches (left or right) twice daily throughout the length of the trial. Vitiliginous patches were monitored with photographs at baseline, every 2 weeks, and 6 months after treatment. Biopsies were performed on subjects with significant results.
Results. Twenty vitiliginous patches from six subjects qualified for evaluation. Fifty percent of patches treated with combination excimer laser and tacrolimus achieved a successful response (75% repigmentation) compared with 20% for the placebo group. Subjects who responded successfully repigmented faster (19%) with combination therapy compared with excimer laser alone. Additionally, three subjects experienced transient hyperpigmentation in lesions treated with combination therapy.
Conclusion. Combining topical immunomodulators with known phototherapeutic modalities may represent a key advancement in the treatment of disease.  相似文献   
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Patients' Expectations of Asthma Treatment   总被引:1,自引:0,他引:1  
A multicomponent model has been developed to explain patients' unmet expectations of medical care. The model proposes that expectations are related to patients' personal experiences with illness, perceived vulnerability to disease, transmitted knowledge, and perceived severity of disease. The objective of this cross-sectional study was to determine whether this model can be applied to patients' unrealistic expectations of treatment outcomes, specifically expecting to be cured of asthma. In total, 230 patients observed in a primary care practice in New York City were interviewed in person with open-ended questions about their expectations of asthma treatment. Responses were analyzed with qualitative techniques to generate categories of expectations. Patients had a mean age of 41 ± 11 years, 21% were white, 30% African American, 42% Latino, and 7% other groups. Major categories of expectations were generated from patients' responses and included symptom relief (expected by 52%), cure (36%), improved physical function (21%), and improved psychological well-being (15%). The category of expecting a cure was assessed with patients' responses to the following items representing components of the model: 1) resource utilization and medication requirements for asthma (representing severity of disease); 2) perceived quality of asthma care and satisfaction with care (representing past asthma experiences); 3) the Asthma Self-Efficacy Scale (representing perceived vulnerability to exacerbations); and 4) experiences of social network contacts with asthma and the Check Your Asthma IQ survey (representing transmitted knowledge). In bivariate analysis, patients who expected a cure were more likely to be Latino or Native American or Asian (p = 0.02), to have never required oral corticosteroids (p = 0.004), to be dissatisfied with the status of their asthma (p = 0.008), to know others who were limited by asthma (p = 0.03), to have worse Asthma Self-Efficacy Scale scores (p = 0.002), to have worse Check Your Asthma IQ scores (p = 0.04), and to currently be taking inhaled corticosteroids (p = 0.03). In multivariate analysis, worse asthma self-efficacy (p = 0.008), never having required oral corticosteroids (p = 0.005), and currently taking inhaled corticosteroids (p = 0.05) remained associated with expecting a cure. As a result of this study, we found that patients have multiple expectations of asthma treatment, including realistic expectations such as symptom relief and improved function, as well as unrealistic expectations, specifically to be cured of asthma. A multicomponent model of patient and disease characteristics was associated with this unrealistic expectation. These findings indicate that clinicians can intervene in diverse areas to foster realistic expectations of treatment outcomes among asthma patients.  相似文献   
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Native American, Hispanic, and Anglo sixth graders reacting to an example of teenage problem drinking expressed similar beliefs and attitudes in many respects. However, Native American children viewed the problem as less serious, subscribed more to a disease theory of alcoholism, attributed less causal responsibility to the individual, and adopted a less aggressive approach toward treatment than did Hispanic, and especially Anglo, children. Their less conventional value orientations accounted for all these differences except their stronger endorsement of a disease theory of problem drinking.  相似文献   
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Summary: The present studies assessed the effects of manipulating extracellular sodium (Na) concentration and Na transport on cellular hypertrophy and hyperplasia in primary culture of rat proximal tubular cells. A concentration-dependent effect on thymidine incorporation and protein content was observed with cell culture media Na concentration of 130, 140 and 150 mmol/L. This effect was independent of osmolality (matched with mannitol) and no stimulatory effect occurred if choline was substituted for Na. Cells derived from sham-operated (Sx) animals exposed to a higher media concentration of Na (150 vs 140 mmol/L) had both stimulated thymidine incorporation to 186.8 ± 35.41% (P<0.05) and enhanced cell protein content to 134.7 ± 135% (P<0.05). This effect was more pronounced in cell cultures derived from unilaterally nephrectomized (Nx) animals, being 212.8 ± 31.5% (P<0.01) for thymidine incorporation (P<0.05 vs cells from sham-operated animals grown in high Na media) and 114.4 ± 3.2% (P<0.001) for protein content (P=0.11 vs sham-operated cells grown in similar conditions). the addition of 10?4 mmol/L ethylisopropyl amiloride hydrochloride (EIPA) to Nx cells in a normal or high Na concentration media resulted in a decrease in cellular protein content to 82.6 ± 6.8% (P<0.05) and 85.5 ± 0.2% (P<0.0001) compared to respective controls. 10?4 mol/L EIPA in media supplemented with insulin-like growth factor (IGF-1) blocked the proliferative response normally seen in response to this growth factor from 156.6 ± 13.7 to 27.5 ± 3.1% (P<0.0001) compared to control. However, the presence of EIPA did not abrogate the hypertrophic response elicited by IGF-1 (cell protein content 128.1 ± 13.1% of control with IGF-1 vs 124.9 ± 12.5 with IGF-1 and EIPA; P= n.s.). Addition of 10?4 mol/L EIPA to 10% serum derived from either Sx or Nx animals blocked the growth response to the sera, limiting the cellular protein content to 76.6 ± 5.5% (P<0.0001) and 89.7 ± 4.4% (P<0.0001) and thymidine incorporation to quiescent levels of 0.2 ± 0.1% (P<0.0001) and 0.4 ± 0.1% (P<0.0001) compared to respective controls. In summary, rat renal proximal tubular cell growth is influenced by Na concentrations in the cell culture environment and inhibited in the presence of EIPA. This supports a role for altered epithelial transport in the cellular growth response to a number of stimuli.  相似文献   
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