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471.
Summary The adrenergic and cholinergic innervation of the bladder was studied in streptozotocin-diabetic rats. The presence of hypertrophy and distension in the diabetic bladders necessitates care in assessing changes occurring in the nerves, factors which are also relevant to clinical histochemical studies. Biochemical assays of cholinergic enzymes revealed decreased activities per g wet weight tissue. However, the total activities of choline acetyltransferase and acetylcholinesterase per whole bladder were significantly increased after 2 weeks of diabetes with greater changes by 8 weeks. Total dopamine levels per bladder were significantly higher than in control rats in the 2-week but not the 8-week group of animals; this may indicate an initial increase in adrenergic nerve activity. There was no impairment in the ability of the detrusor muscle to respond to noradrenaline, acetylcholine or to cholinergic nerve stimulation. Shortly after induction of diabetes streptozotocin-treated rats display polyuria. It is proposed that the activity of the bladder is therefore stimulated to allow greater volumes of urine to be passed. The results are discussed in relation to human diabetes mellitus where clinical studies have implicated a neuropathic origin to bladder dysfunction.  相似文献   
472.
Increased urinary lipoperoxides in drug abusers   总被引:2,自引:0,他引:2  
Urine lipoperoxides were measured, as the malondialdehyde-thiobarbituric acid adduct, by "high performance" liquid chromatography in men who tested positive for any of the common "drugs of abuse." Urine malondialdehyde concentrations were within the reference range in those urines containing barbiturates and amphetamines. On the other hand, significant urine malondialdehyde elevations were associated with those testing positive for marijuana (p less than 0.005), cocaine, opiates, benzodiazepines, and in those urines containing multiple drugs (p less than 0.001). The mechanism of tissue damage by these drugs is not necessarily by lipid peroxidation, since their primary toxic effects might result in cellular injury by an alternative mechanism; the observed increased lipid peroxidation could be a secondary phenomenon following tissue injury.  相似文献   
473.
Ward community groups have been mostly lost from acute psychiatric in-patient settings in recent years with changes related to care in the community and altered therapeutic expectations. This paper outlines the re-introduction of ward community groups to such a setting and, by using the quantitative measure of patient complaints and qualitative observations, offers evidence for their usefulness as a therapeutic medium, beneficial to the acute psychiatric in-patient ward, and as a container for disturbed states.  相似文献   
474.
Given the progress in the symptomatic treatment of breathlessness, and the physical and psychological morbidity associated with chronic breathlessness, estimates of the size of the population that may benefit from better support become imperative. Prevalence estimates have varied widely (0.9% of clinical encounters to 32%) and have largely relied only on respondents who used clinical services. Whole-of-population approaches may be able to define better the “true” prevalence of chronic breathlessness and quantify exertion limited by breathlessness. The aim of this study was to estimate population levels of chronic breathlessness, severity of limits to exercise, and demographic predictors of the presence of breathlessness. A whole-of-population face-to-face survey method (n = 8,396) in South Australia was used, directly standardized for age, gender, country of birth, and rurality. Respondents were asked about breathlessness and levels of exertion causing breathlessness for at least three of the last six months using a modified Medical Research Council dyspnea scale. Univariate and multivariate analyses identify the demographic characteristics of people more likely to experience chronic breathlessness. With a participation rate of 65.3%, 8.9% of respondents had breathlessness that chronically limited exertion. Significant associations with chronic breathlessness in multivariate analysis included female sex (P < 0.001), not working full time (P < 0.001), low income (P = 0.007), and older age (P = 0.031). There are significant levels of chronic breathlessness in the community. Given the prevalence, it is feasible to explore the onset of breathlessness, the underlying etiologies and subsequent health service utilization, and health consequences.  相似文献   
475.
This study aimed to review the evidence for the use of long-term oxygen therapy for patients with chronic obstructive pulmonary disease (COPD). The design was a systematic Cochrane review of randomized controlled trials (RCTs) of long-term oxygen therapy for COPD and main outcome measure was survival on home oxygen therapy. Five RCTs were identified. Data from two trials of nocturnal oxygen therapy in mild to moderate hypoxaemia were aggregated. Data from the other three trials could not be aggregated because of differences in trial design and patient selection. Treatment with continuous versus nocturnal oxygen therapy produced a significant improvement in mortality after 24 months [Peto odds ratio 0.45, 95% confidence interval (95% CI) 0.25-0.81] for the continuous therapy group. Treatment with oxygen therapy versus no oxygen therapy showed a significant improvement in mortality after five years in the group receiving oxygen therapy (Peto odds ratio 0.42, 95% CI 0.18-0.98). There was no difference in mortality for patients with COPD and mild to moderate daytime hypoxaemia and nocturnal desaturation receiving nocturnal oxygen therapy versus no oxygen therapy or sham treatment. Long-term oxygen therapy versus no oxygen therapy in patients with COPD and moderate hypoxaemia had no effect on survival. In conclusion, long-term oxygen therapy improved survival in a selected group of COPD patients with severe hypoxaemia but few co-morbidities. Long-term oxygen therapy did not improve survival in patients with moderate hypoxaemia or in those with mild to moderate hypoxaemia and arterial desaturation at night.  相似文献   
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OBJECTIVES: To describe dermatology journal uniform resource locator (URL) use and persistence and to better understand the level of control and awareness of authors regarding the availability of the URLs they cite. DESIGN: Software was written to automatically access URLs in articles published between January 1, 1999, and September 30, 2004, in the 3 dermatology journals with the highest scientific impact. Authors of publications with unavailable URLs were surveyed regarding URL content, availability, and preservation. MAIN OUTCOME MEASURES: Uniform resource locator use and persistence and author opinions and practices. RESULTS: The percentage of articles containing at least 1 URL increased from 2.3% in 1999 to 13.5% in 2004. Of the 1113 URLs, 81.7% were available (decreasing with time since publication from 89.1% of 2004 URLs to 65.4% of 1999 URLs) (P<.001). Uniform resource locator unavailability was highest in The Journal of Investigative Dermatology (22.1%) and lowest in the Archives of Dermatology (14.8%) (P=.03). Some content was partially recoverable via the Internet Archive for 120 of the 204 unavailable URLs. Most authors (55.2%) agreed that the unavailable URL content was important to the publication, but few controlled URL availability personally (5%) or with the help of others (employees, colleagues, and friends) (6.7%). CONCLUSIONS: Uniform resource locators are increasingly used and lost in dermatology journals. Loss will continue until better preservation policies are adopted.  相似文献   
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Previous characterization of mouse chromosome 2 identified genomic intervals that influence obesity, insulin resistance, and dyslipidemia. For this, resistant CAST/Ei (CAST) alleles were introgressed onto a susceptible C57BL/6J background to generate congenic strains with CAST alleles encompassing 67-162 Mb (multigenic obesity 6 [MOB6]) and 84-180 Mb (MOB5) from mouse chromosome 2. To examine the effects of each congenic locus on atherosclerosis and glucose disposal, we bred each strain onto a sensitizing LDL receptor-null (LDLR(-/-)) C57BL/6J background to predispose them to hypercholesterolemia and insulin resistance. LDLR(-/-) congenics and controls were characterized for measures of atherogenesis, insulin sensitivity, and obesity. We identified a genomic interval unique to the MOB6 congenic (72-84 Mb) that dramatically decreased atherosclerosis by approximately threefold and decreased insulin resistance. This region also reduced adiposity twofold. Conversely, the congenic region unique to MOB5 (162-180 Mb) increased insulin resistance but had little effect on atherosclerosis and adiposity. The MOB congenic intervals are concordant to human and rat quantitative trait loci influencing diabetes and atherosclerosis traits. Thus, our results define a strategy for studying the poorly understood interactions between diabetes and atherosclerosis and for identifying genes underlying the cardiovascular complications of insulin resistance.  相似文献   
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