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61.
Despite progress in reduction in maternal deaths in South Africa, deaths due to complications of hypertension in pregnancy remain high at 26 deaths per 100 000 live births in 2016. The South African health ministry modified its existing four-visit antenatal care model to align with the World Health Organization’s (WHO) 2016 recommendations for the number and content of antenatal care contacts. Implementation of the eight-contact antenatal care recommendations began in April 2017, after adaptation to the national context and nationwide trainings. In this article, we describe the stages of implementation and the monitoring of key indicators. We share lessons, particularly from the important early stages of nationwide scale-up and an analysis of the early results. We analysed samples of maternity case records in four catchment areas in the first year of the updated care model. The mean number of antenatal care contacts among five monthly samples of 200 women increased steadily from 4.76 (standard deviation, SD: 2.0) in March 2017 to 5.90 (SD: 2.3) in February 2018. The proportion of women with hypertension detected who received appropriate action (provision of medical treatment or referral) also increased from 83.3% (20/24) to 100.0% (35/35) over the same period. South Africa’s experiences with implementation of the updated antenatal care package shows that commitment from all stakeholders is essential for success. Training and readiness are key to identifying and managing women with complications and developing an efficient antenatal care system accessible to all women.  相似文献   
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This study evaluated Doppler flow velocimetry of the umbilical artery in patients with suspected intrauterine growth retardation as detected by poor symphysis-fundus growth (SFG). The sensitivity of Doppler in detecting light for gestational age babies and intrauterine growth retardation was poor. Antenatal complications, neonatal morbidity and perinatal mortality occurred significantly more frequently in patients with abnormal flow. Doppler flow velocimetry is an excellent test to identify babies at high risk for perinatal morbidity and mortality, when poor SFG is present.  相似文献   
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Background Chronic renal failure is known to cause various nail pathologies. They may be directly related to the renal condition itself or its complications or to the therapy. Objective To compare nail changes in end‐stage renal failure patients under haemodialysis with healthy persons and to study the potential relationship with various parameters in the patients. Patients and Methods The study comprised 100 patients with chronic renal failure under regular haemodialysis as well as 100 healthy control subjects of matched age and sex. Both groups were subjected to full history taking and thorough general and nail examination. Complete blood picture, liver and kidney function tests and fasting blood glucose level were investigated. Results Nail disorders were more prevalent in patients (76%) than in control group (30%). The half and half nail was the most common finding (20%) followed by – in descending manner – absent lunula, onycholysis, brittle nail, Beau's lines, clubbing, longitudinal ridging, onychomycosis, subungual hyperkeratosis, koilonychias, total leukonychia, splinter hemorrhage, pitting and pincer nail deformity. There was non‐significant correlation between nail changes and age of the patients or duration of haemodialysis. In addition, no evidence of significant relation was found between nail changes and both haemoglobin and albumin levels. Conclusion Frequent nail changes are observed on systematic nail examination of uraemic patients undergoing haemodialysis; however, the cause of them remains obscure and could not be traced to a particular abnormality in the renal condition, medication or the procedure itself and it needs further investigations.  相似文献   
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Compared with our understanding of endochondral ossification, much less is known about the coordinated arrest of growth defined by the narrowing and fusion of the cartilaginous growth plate. Throughout the musculoskeletal system, appropriate cell and tissue responses to mechanical force delineate morphogenesis and ensure lifelong health. It remains unclear how mechanical cues are integrated into many biological programs, including those coordinating the ossification of the adolescent growth plate at the cessation of growth. Primary cilia are microtubule-based organelles tuning a range of cell activities, including signaling cascades activated or modulated by extracellular biophysical cues. Cilia have been proposed to directly facilitate cell mechanotransduction. To explore the influence of primary cilia in the mouse adolescent limb, we conditionally targeted the ciliary gene Intraflagellar transport protein 88 (Ift88fl/fl) in the juvenile and adolescent skeleton using a cartilage-specific, inducible Cre (AggrecanCreERT2 Ift88fl/fl). Deletion of IFT88 in cartilage, which reduced ciliation in the growth plate, disrupted chondrocyte differentiation, cartilage resorption, and mineralization. These effects were largely restricted to peripheral tibial regions beneath the load-bearing compartments of the knee. These regions were typified by an enlarged population of hypertrophic chondrocytes. Although normal patterns of hedgehog signaling were maintained, targeting IFT88 inhibited hypertrophic chondrocyte VEGF expression and downstream vascular recruitment, osteoclastic activity, and the replacement of cartilage with bone. In control mice, increases to physiological loading also impair ossification in the peripheral growth plate, mimicking the effects of IFT88 deletion. Limb immobilization inhibited changes to VEGF expression and epiphyseal morphology in Ift88cKO mice, indicating the effects of depletion of IFT88 in the adolescent growth plate are mechano-dependent. We propose that during this pivotal phase in adolescent skeletal maturation, ciliary IFT88 protects uniform, coordinated ossification of the growth plate from an otherwise disruptive heterogeneity of physiological mechanical forces. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
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OBJECTIVE : To determine and compare the efficacy of 5‐day t.d.s and 7‐day b.d. treatment regimens comprising lansoprazole, clarithromycin and amoxicillin in the eradication of Helicobacter pylori. METHODS : Patients with unequivocal evidence of H. pylori infection based on histology and rapid urease tests of both antrum and corpus biopsies were recruited for the study. The study was a randomized, investigator‐blind, comparative study. Patients received either 500 mg clarithromycin t.d.s. and 500 mg amoxicillin t.d.s. for 5 days (LAC5) or 500 mg clarithromycin b.d. and 500 mg amoxicillin b.d. for 7 days (LAC7) together with 30 mg lansoprazole (both groups) daily for either 5 or 7 days, depending on the treatment group. Patients were assessed for the successful eradication of H. pylori, defined as the absence of bacteria based on histology and urease tests on both antral and corporeal biopsies, carried out at least 4 weeks after completion of the therapy. RESULTS : One hundred and eight patients were recruited for the study. In the LAC5 treatment group, four patients failed to return for follow up and in the LAC7 group, two failed to return for follow up and two were not compliant with medications. Eradication rates based on an intention‐to‐treat analysis were: 46/54 for LAC5 (85.2%; 95% CI = 72.9–93.4) and 47/54 for LAC7 (87.0%; 95% CI = 75.1–94.6). Based on a per protocol analysis, the rates were: 46/50 for LAC5 (92.0%; 95% CI = 80.8–97.8) and 47/50 for LAC7 (94.0%; 95% CI = 83.5–98.7). Both treatment regimens were convenient for patients and except for two patients in the LAC7 group, all patients reported taking 100% of all prescribed medications. The side‐effects encountered were uniformly mild and no patient discontinued treatment because of intolerance to medications. The most common side‐effects were altered taste (LAC5 64.7%; LAC7 78.8%). Diarrhea, nausea and anorexia were reported in a minority of patients. CONCLUSIONS : Both the LAC5 t.d.s. and the LAC7 b.d. treatment regimens were well tolerated by patients and were highly effective in the eradication of H. pylori.  相似文献   
68.
The effect of cefoperazone, a third-generation cephalosporin, on biliary lipid secretion in rats was examined. Rats were anesthetized with ether and the mid-lumbar vein and common bile duct cannulated. Bile acid secretion was maintained by intravenous taurocholic acid infusion (28 mol/hr). A 1-hr control period was followed by intravenous cefoperazone infusion at either submaximal (20 mol/hr), or supramaximal (60 mol/hr) concentrations. At the cefoperazone infusion rate of 20 mol/hr (biliary secretion of 7.1±1.6 mol/hr) phospholipid secretion fell 19% and cholesterol secretion fell 31%; at a cefoperazone infusion rate of 60 mol/hr (biliary secretion rate of 27.1±5.1 mol/hr) phospholipid and cholesterol secretion were further reduced 40% and 56%, respectively, of controls. All changes were significant (P<0.01). Inhibition of both cholesterol and phospholipid secretion paralleled each other, was dose-dependent, and reversible. Cefoperazone's inhibitory action was abolished at a bile acid infusion rate of 108 mol/hr. Cefoperazone was not found to be associated with bile acid micelles or mixed micelles as determined by ultracentrifugation and gel filtration. Thus, the effect of cefoperazone on biliary lipid secretion is not due to the impairment of mixed micelle formation in the canalicular lumen but rather its inhibitory effect appears to be due to a presecretory event.  相似文献   
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Problem

Suboptimal care contributes to perinatal mortality rates. Quality-of-care audits can be used to identify and change suboptimal care, but it is not known if such audits have reduced perinatal mortality in South Africa.

Approach

We investigated perinatal mortality trends in health facilities that had completed at least five years of quality-of-care audits. In a subset of facilities that began audits from 2006, we analysed modifiable factors that may have contributed to perinatal deaths.

Local setting

Since the 1990s, the perinatal problem identification programme has performed quality-of-care audits in South Africa to record perinatal deaths, identify modifiable factors and motivate change.

Relevant changes

Five years of continuous audits were available for 163 facilities. Perinatal mortality rates decreased in 48 facilities (29%) and increased in 52 (32%). Among the subset of facilities that began audits in 2006, there was a decrease in perinatal mortality of 30% (16/54) but an increase in 35% (19/54). Facilities with increasing perinatal mortality were more likely to identify the following contributing factors: patient delay in seeking help when a baby was ill (odds ratio, OR: 4.67; 95% confidence interval, CI: 1.99–10.97); lack of use of antenatal steroids (OR: 9.57; 95% CI: 2.97–30.81); lack of nursing personnel (OR: 2.67; 95% CI: 1.34–5.33); fetal distress not detected antepartum when the fetus is monitored (OR: 2.92; 95% CI: 1.47–5.8) and poor progress in labour with incorrect interpretation of the partogram (OR: 2.77; 95% CI: 1.43–5.34).

Lessons learnt

Quality-of-care audits were not shown to improve perinatal mortality in this study.  相似文献   
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