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81.
82.

Purpose

Contrast induced nephropathy (CIN) is defined as a decrease in renal function following administration of contrast media. The aim of this meta-analysis was to asses the overall risk of CIN, chronic loss of kidney function and the need for renal replacement therapy (RRT) after intravenous contrast enhanced CT-scan. Secondly, we aimed to identify subgroups at increased risk for CIN.

Materials and methods

A literature search in Pubmed, Medline, Embase and Cochrane databases was performed. Data extraction was carried out independently by two reviewers. Meta-analysis and meta-regression were performed using an exact likelihood approach.

Results

Forty studies evaluating the incidence of CIN after CT were included. The pooled incidence of CIN was 6.4% (95% CI 5.0–8.1). The risk of RRT after CIN was low, 0.06% (95% CI 0.01–0.4). The decline in renal function persisted in 1.1% of patients (95% CI 0.6–2.1%). Patients with chronic kidney disease (odds ratio 2.26, p < 0.001) or diabetes mellitus (odds ratio 3.10, p < 0.001) were at increased risk for the development of CIN.

Conclusion

CIN occurred in 6% of patients after contrast enhanced CT. In 1% of all patients undergoing contrast enhanced CT the decline in renal function persisted.  相似文献   
83.
Development and manufacture of nanomaterials is growing at an exponential rate, despite an incomplete understanding of how their physicochemical characteristics affect their potential toxicity. Redox activity has been suggested to be an important physicochemical property of nanomaterials to predict their biological activity. This study assessed the influence of redox activity by modification of cerium dioxide nanoparticles (CeO2 NPs) via zirconium (Zr) doping on the biodistribution, pulmonary and cardiovascular effects in mice following inhalation. Healthy mice (C57BL/6?J), mice prone to cardiovascular disease (ApoE?/?, western-diet fed) and a mouse model of neurological disease (5?×?FAD) were exposed via nose-only inhalation to CeO2 NPs with varying amounts of Zr-doping (0%, 27% or 78% Zr), or clean air, over a four-week period (4?mg/m3 for 3?h/day, 5?days/week). Effects were assessed four weeks post-exposure. In all three mouse models CeO2 NP exposure had no major toxicological effects apart from some modest inflammatory histopathology in the lung, which was not related to the amount of Zr-doping. In ApoE?/? mice CeO2 did not change the size of atherosclerotic plaques, but there was a trend towards increased inflammatory cell content in relation to the Zr content of the CeO2 NPs. These findings show that subacute inhalation of CeO2 NPs causes minimal pulmonary and cardiovascular effect four weeks post-exposure and that Zr-doping of CeO2 NPs has limited effect on these responses. Further studies with nanomaterials with a higher inherent toxicity or a broader range of redox activities are needed to fully assess the influence of redox activity on the toxicity of nanomaterials.  相似文献   
84.
The aim of the present systematic review was to evaluate the available evidence on laboratory diagnosis of CDI and to formulate recommendations to optimize CDI testing. In comparison with cell culture cytotoxicity assay (CCA) and toxigenic culture (TC) of stools, we analyzed the test characteristics of 13 commercial available enzyme immunoasssays (EIA) detecting toxins A and/or B, 4 EIAs detecting Clostridium difficile glutamate dehydrogenase (GDH), and a real-time PCR for C. difficile toxin B gene. In comparison with CCA and TCA and assuming a prevalence of CDI of 5%, PPV and NPV varied between 0.28–0.77, 0.12–0.65 and 0.98–1.00, 0.97–1.00, respectively. Only if the tests were performed in a population with a CDI prevalence of 50 percent, would PPVs be acceptable (ranging from 0.71 to 1.00).To overcome the problem of a low PPV, we propose a two step approach, with a second test or a reference method in case of a positive first test. Further reducing the number of false negative results would require either retesting of all subjects with a negative first test, or re-testing all subjects with a negative second test, after an initially positive test. This approach resulted in non-significant improvements, and emphasizes the need for better diagnostic tests. Further studies to validate the applicability of two-step testing, including assessment of clinical features, are required.  相似文献   
85.
Medicine, Health Care and Philosophy -  相似文献   
86.
BACKGROUND: Obesity is associated with multiple health problems, often originating in childhood. OBJECTIVE: The objective was to investigate differences in the development of adiposity from childhood to adulthood as related to race, sex, and socioeconomic status (SES). DESIGN: Individual growth curve modeling for waist circumference, body mass index, and sum of skinfold thicknesses (triceps, subscapular, and suprailiac) was performed in an 11-y cohort study of 622 African Americans and European Americans aged 4.2-27.5 y. We examined the development of adiposity in 2 ways: 1) differences related to race, sex, and parents' education (SES), and 2) differences between obese, overweight, and normal-weight persons at the end of their childhood (> 17 y of age). RESULTS: The sum of skinfold thicknesses was greater in females than in males, with a larger increase with age. Race, sex, and SES showed a complex relation with body mass index and the sum of skinfold thicknesses. The low-SES group showed the fastest increase in waist circumference with age. The obese group showed the most rapid increase in the 3 measures of adiposity. Growth curves for the obese group were distinguishable from those for the normal-weight persons at an earlier age for African Americans than for European Americans. CONCLUSIONS: The development rate of adiposity from childhood into early adulthood is influenced by sex and SES but not by race. However, race, sex, and SES had joint effects on adiposity levels. The development of obesity can begin to be distinguished in midchildhood, but the age at which this distinction becomes apparent depends on race.  相似文献   
87.
The vulnerability of motoneurones to glutamate has been implicated in neurological disorders such as amyotrophic lateral sclerosis but it is not known whether specific receptor subtypes mediate this effect. In order to investigate this further, the expression of N-methyl-D-aspartate (NMDA) receptor subunits was studied during the first three post-natal weeks when motoneurones are differentially vulnerable to injury following neonatal nerve crush compared to the adult. Unilateral nerve crush was carried out at day 2 after birth (P2) which causes a decrease of 66% in motoneurone number by 14 days (P14). To study receptor expression in identified motoneurones, serial section analysis was carried out on retrogradely labelled common peroneal (CP) motoneurones by combined immunocytochemistry and in situ hybridization (ISH). mRNA levels were also quantified in homogenates from lumbar spinal cords in which the side ipsilateral to the crush was separated from the contralateral side. The NR1 subunit of the NMDA receptor was widely distributed in the spinal cord being expressed most strongly in motoneurone somata particularly during the neonatal period (P3-P7). The NR2 subunits were also expressed at higher levels in the somata and dendrites of neonatal motoneurones compared to older animals. NR2B mRNA was expressed at low to moderate levels throughout the studied period whereas NR2A mRNA levels were low until P21. Following unilateral nerve crush, an initial decrease in NR1 mRNA occurred at one day after nerve crush (P3) in labelled CP motoneurones ipsilateral to the crush which was followed by a significant increase in NR1 subunit expression at 5 days post-injury. This increase was bilateral although reaching greater significance ipsilateral to the crush compared with sham-operated animals. A significant increase in NR1 and NR2B mRNA post injury was also detected in spinal cord homogenates. In addition, the changes in levels of NR1 and NR2B mRNA were reflected by comparable bilateral changes at P7 in receptor protein determined by quantitative immunocytochemical analysis of NR1 and NR2 subunit expression in identified CP motoneurones indicating a co-ordinated regulation of receptor subunits in response to injury.  相似文献   
88.
A lack of specific autobiographical memory may result from exposure to psychological trauma, intrusive memories of adverse events, and/or a general memory deficit. This study explored the role of these variables in 25 patients with various psychiatric diagnoses and 15 healthy controls. All participants had been exposed to war atrocities during their childhood in Indonesia. Patients produced significantly less specific memories than did controls. In addition, rather than performance on general neuropsychological memory tests, the frequent occurrence of intrusive memories and the avoidance of reminders of trauma predicted less autobiographical memory specificity. These results replicate and extend earlier findings on intrusive and nonspecific autobiographical memory in depressed samples to a group of people who experienced war atrocities in childhood.  相似文献   
89.
Medicine does not usually consider the human body from an aesthetic point of view. This article explores the notion of the lived body as aesthetic object in anthropological medicine, concentrating on the views of Buytendijk and Straus on human uprightness and gracefulness. It is argued that their insights constitute a counter-balance to the way the human body is predominantly approached in medicine and medical ethics. In particular, (1) the relationship between anthropological, aesthetic and ethical norms, (2) the possible danger of a naturalistic fallacy, (3) the implications for the care of disabled people and (4) the intrinsic aesthetic quality of the human body are dealt with. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
90.
BACKGROUND: Rabeprazole sodium is the newest member of a class of substituted benzimidazole molecules known as proton pump inhibitors. Other proton pump inhibitors have been shown to be effective in healing active duodenal ulcer. METHOD: This randomized, double-blind, multicentre study, conducted at 25 European sites, compared the efficacy and tolerability of rabeprazole and omeprazole in patients with active duodenal ulcers. One hundred and two patients with active duodenal ulcer received rabeprazole 20 mg and 103 patients omeprazole 20 mg once daily for 2 or 4 weeks, with ulcer healing monitored by endoscopy. RESULTS: After 2 weeks, complete ulcer healing was documented in 69% of patients given rabeprazole 20 mg and in 62% of patients given omeprazole 20 mg (N.S.). After 4 weeks, healing rates were 98% in the rabeprazole group and 93% in the omeprazole group (P = 0.083). Rabeprazole-treated patients had significantly greater improvement in daytime pain symptom relief than those treated with omeprazole at the conclusion of the study (P = 0.038). Both drugs were well tolerated over the 4-week treatment period. Mean changes from baseline to end-point in fasting serum gastrin were significantly greater in the rabeprazole group, but at end-point mean values were well within normal limits for both groups. No clinically meaningful changes or other between-group differences were observed in laboratory parameters. CONCLUSION: In this study, rabeprazole produced healing rates equivalent to omeprazole at weeks 2 and 4, and provided significantly greater improvement in daytime pain. Both treatments were well tolerated.  相似文献   
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