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PURPOSE: This study examined the nature of the variability in salivary immunoglobulin and albumin concentrations within an individual, between individuals, and between populations with differing levels of habitual physical activity. METHODS: Fourteen elite swimmers, and 21 active and 18 sedentary individuals provided 12 saliva samples over a 30-d period. Group classifications were based on interviews, anthropometric measurements, and physical activity records. Symptoms of illness and physical activity data were recorded daily. Salivary IgA, IgG, and IgM were measured by ELISA, and albumin concentrations were measured by nephelometry. Variability was assessed using ANOVA procedures. RESULTS: Elite swimmers, compared with active and sedentary individuals, had higher concentrations of salivary IgA (geometric mean=65 vs 32 and 40 mg.L, P=0.002) and greater variability in salivary IgA concentrations as individuals (P=0.007) and as a group (P=0.03). Salivary IgG variability in swimmers was also twofold greater than the other two groups (P=0.008). Salivary IgM and albumin variability were not significantly different between groups, but individual variability differed for swimmers and active individuals. The intraclass correlations for salivary IgA and IgG (but not for IgM or albumin) were 50% lower for swimmers than the other two groups (ICC for IgA: 20% swimmers vs 54% active and 46% sedentary individuals; ICC for IgG: 36 vs 59 and 57%). CONCLUSION: The variability and fluctuation of salivary immunoglobulin concentrations were consistently greater in the elite swimmers, but multiple samples from individual swimmers were less correlated compared with participants with lower physical activity levels. These findings have implications for monitoring mucosal immune status within individuals and when comparing salivary immunoglobulin concentrations between groups with differing levels of physical fitness and activity.  相似文献   
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Objectives: To determine individual differences in the impact of illness on the change in performance of swimmers in international competitions. Methods: Subjects were members of the Australian swimming team (33 male and 39 female, aged 15–27 years). Swimmers provided a weekly seven day recall of symptoms of illness during final six weeks of preparations for international competition over a three year period. Swimmers were categorised as either ill (one or more episodes of illness) or healthy. The measure of performances was the international point score. Mean changes in points score were calculated for healthy and ill swimmers between a national championship and an international competition (∼16 weeks later). Likelihoods of substantial effects of illness on an individual''s true change in performance (beneficial/trivial/harmful) were estimated from means and standard deviations, assuming a smallest substantial change of 6 points. Results: Illness was reported before international performances by 38% of female and 35% of male swimmers. For female swimmers the change in performance was –3.7 (21.5) points (mean (SD)) with illness and –2.6 (19.0) points when healthy; for male swimmers the changes were –1.4 (17.5) points with illness and 5.6 (13.2) points when healthy. The likelihoods that illness had a substantial beneficial/trivial/harmful effect on performance of an individual swimmer were 32%/31%/37% for female and 17%/31%/52% for male participants (90% confidence limits ∼±10% to 20%). Conclusions: Although mild illness had only a trivial mean effect on female swimmers and a small harmful mean effect on male swimmers, there were substantial chances of benefit and harm for individuals.  相似文献   
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A comprehensive review of shoulder impingement reveals numerous causes, contributing factors, and therapeutic options for the resolution of symptoms and return to optimal shoulder function. The clinical diagnosis of shoulder impingement is rather straightforward, but the challenge arises in identifying causative factors and directing treatment options to alleviate symptoms and restore normal function. Shoulder impingement occurs when the space between the proximal humerus and the coracoacromial arch is narrowed such that the transversing tendons, primarily the supraspinatus and to a lesser degree, the infraspinatus, are injured. As the most diagnosed shoulder ailment an understanding of shoulder anatomy, supporting musculature and function, inciting factors, and individual demands are critical in directing the appropriate treatment plan. Medications, therapeutic exercise and surgical interventions all have their place in the treatment of shoulder impingement.  相似文献   
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OBJECT: Cerebral vasospasm is a common cause of morbidity and death following aneurysmal subarachnoid hemorrhage (SAH). Previous research has shown that bilirubin oxidation products (BOXes) are present in the cerebral spinal fluid in patients with SAH-induced cerebral vasospasm and can contribute to vasoconstriction and vasospasm in vitro and in vivo. The events leading to cerebral vasospasm are not understood; however, one component of the occlusion may be due to vascular remodeling. In this study the authors have investigated the actions of BOXes, okadaic acid ([OA], a phosphatase inhibitor), and phorbol-12 myristate-13 acetate ([PMA], a protein kinase activator) on vascular smooth-muscle cell (VSMC) morphology and metabolism. METHODS: Immunohistochemical analysis was performed to assess VSMC morphology and alpha-smooth-muscle actin (alphaSMA) distribution following the application of BOXes, OA, or PMA. Changes in the level of lactate dehydrogenase (LDH) release and oxidative metabolism were also measured. The BOXes, OA, or PMA caused VSMCs to change their shape and exhibit altered alphaSMA distribution. These treatments increased LDH release (p < 0.05), which is an index of increased cell stress. Oxidative metabolism significantly increased at low and high doses of BOXes, that is, 143 +/- 8.5% and 180 +/- 11.8%, respectively (p < 0.0001). Both PMA and OA also caused a significant increase in metabolism. CONCLUSIONS: The authors concluded that BOXes, OA, and PMA alter VSMC morphology and metabolic activity, events that have been observed during vascular remodeling. Although the mechanism remains unclear, the results indicate that BOXes may play a role in the vascular remodeling that occurs following aneurysmal SAH.  相似文献   
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The relationship between quality and outcomes in routine depression care   总被引:3,自引:0,他引:3  
OBJECTIVE: This longitudinal, nonexperimental study examined whether depression treatment provided in concordance with guidelines developed by the Agency for Healthcare Research and Quality (AHRQ) is associated with improved clinical outcomes. METHODS: The medical, insurance, and pharmacy records of a community-based sample of 435 subjects who screened positive for current major depression were abstracted to ascertain whether depression treatment was received and whether it was provided in accordance with AHRQ guidelines. Regression analyses estimated the impact of guideline-concordant treatment on the change in depression severity and on mental and physical health over a six-month period. An instrumental variables analysis was used to check the sensitivity of the results to selection bias. RESULTS: A total of 106 subjects were treated for depression by 105 different primary care and specialty providers. Sixty percent of the sample had current major depression, and about 40 percent had subthreshold depression. Only 29 percent of the patients received guideline-concordant treatment. For patients with major depression, guideline-concordant care was significantly and substantially associated with improved depression severity but not with improvements in overall mental or physical health. The instrumental variables analysis indicated that the standard regression analysis underestimated the treatment effect by 21 percent. For those with subthreshold depression, guideline-concordant care was not associated with improved outcomes. DISCUSSION AND CONCLUSIONS: This community-based, nonexperimental study found a positive relationship between the quality of care for depression and clinical outcomes for patients with major depression in routine practice settings.  相似文献   
48.
PURPOSE: Exercise and training are known to elicit changes in mucosal humoral immunity, but whether these alterations have any impact on competitive performance remains unclear. This investigation examined relationships between salivary immunoglobulin (Ig) concentration, the incidence of respiratory tract illness (RTI), and competitive performance in elite swimmers. METHODS: Forty-one members of the Australian Swimming Team (21 males and 20 females) aged 15-27 yr were monitored during preparations for the 1998 Commonwealth Games. Twenty-five coaches and staff (19 males and 6 females) aged 32-65 yr, serving as "environmental controls," were also monitored. Salivary IgA, IgM, and IgG and albumin concentration (mg.L-1) were measured in both groups in May 1998 and again in August 1998, 17 d before competition. Subjects were categorized as "ill" (at least one RTI) or "healthy". RESULTS: There were no significant changes in salivary IgA, IgM, or IgG concentration in the swimmers between May and August, nor were there any differences between healthy (N = 23) and ill (N = 18) swimmers. There was a significant positive relationship between IgM and performance in the male swimmers (r = 0.85, P < 0.001) but not for any other parameter. There was no significant difference in performance between ill and healthy swimmers (P = 0.11). Gold medal winners (N = 9) had higher IgM levels than other swimmers (N = 32) in May (P = 0.02) and higher IgG in August (P = 0.02). CONCLUSION: These data indicate that a season of training by elite swimmers did not alter salivary immunoglobulin concentrations, and the presence of RTI had no significant impact on competitive performance.  相似文献   
49.
Epidemic dropsy is a potentially life‐threatening condition resulting from the ingestion of argemone oil derived from the seeds of Argemone mexicana Linn. Exposure to argemone oil is usually inadvertent, arising from mustard cooking oil adulteration. Sanguinarine, an alkaloid present in argemone oil, has been postulated as a causative agent with the severity of epidemic dropsy correlating with plasma sanguinarine levels. Cases of epidemic dropsy have also been reported following the topical application of argemone containing massage oil. Black salve, a topical skin cancer therapy also contains sanguinarine, but at significantly higher concentrations than that reported for contaminated massage oil. Although not reported to date, a theoretical risk therefore exists of black salve inducing epidemic dropsy. This literature review explores the presentation and pathophysiology of epidemic dropsy and assesses the risk of it being induced by black salve.  相似文献   
50.
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