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51.
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
52.
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
53.

Background  

National recommendations supporting the promotion of multiple short (10+ minute) physical activity bouts each day to increase overall physical activity levels in middle-aged and older adults underscore the need to identify antecedents and correlates of such daily physical activity episodes.  相似文献   
54.
People with amnestic mild cognitive impairment (aMCI), compared to healthy older adults (HO), benefit less from semantic congruent cues during episodic encoding. The presence of the apolipoprotein E (APOE) ?4 makes this congruency benefit smaller, but the neural correlates of this deficit are unknown. Here, we estimated the source generators of EEG oscillatory activity associated with successful encoding of face‐location associations preceded by semantically congruent and incongruent cues in HO (N = 26) and aMCI subjects (N = 34), 16 of which were ?4 carriers (?4+) and 18 ?4 noncarriers (?4?). Source estimation was performed in those spectrotemporal windows where the power of low‐alpha, high‐alpha, and beta oscillatory activity differed either between congruent and incongruent faces or between groups. Differences in high‐alpha and beta‐oscillatory dynamics indicated that aMCI ?4+ are unable to activate lateral regions of the temporal lobe involved in associative memory and congruency benefit in HO. Interestingly, and regardless of APOE genotype, aMCI activated additional regions relative to HO, through alpha oscillations. However, only activation in a distributed fronto‐temporo‐parietal network in ?4 noncarriers was paralleled by enhanced memory. On the contrary, the redundant prefrontal activation shown by aMCI ?4+ did not prevent performance from decreasing. These results indicate that the effect of aMCI‐related degeneracy on functional networks is constrained by the presence of APOE ?4. Whereas individuals with aMCI ?4? activate attentional, perceptual and semantic compensatory networks, aMCI ?4+ show reduced processing efficiency and capacity. © 2015 Wiley Periodicals, Inc.  相似文献   
55.
Blindness due to corneal diseases is a common pathology affecting up to 23 million individuals worldwide. The tissue‐engineered anterior human cornea, which is currently being tested in a Phase I/II clinical trial to treat severe corneal trophic ulcers with preliminary good feasibility and safety results. This bioartificial cornea is based on a nanostructured fibrin–agarose biomaterial containing human allogeneic stromal keratocytes and cornea epithelial cells, mimicking the human native anterior cornea in terms of optical, mechanical, and biological behavior. This product is manufactured as a clinical‐grade tissue engineering product, fulfilling European requirements and regulations. The clinical translation process included several phases: an initial in vitro and in vivo preclinical research plan, including preclinical advice from the Spanish Medicines Agency followed by additional preclinical development, the adaptation of the biofabrication protocols to a good manufacturing practice manufacturing process, including all quality controls required, and the design of an advanced therapy clinical trial. The experimental development and successful translation of advanced therapy medicinal products for clinical application has to overcome many obstacles, especially when undertaken by academia or SMEs. We expect that our experience and research strategy may help future researchers to efficiently transfer their preclinical results into the clinical settings.  相似文献   
56.
Aim The aim of this study was to analyse the characteristics of horseshoe tract formation in anal fistula. Method We retrospectively analysed the data from all consecutive patients who underwent surgery for an anal fistula from November 2004 to March 2011. A horseshoe tract was defined as a circumferential extension connecting both sides of the anorectum. Results During the period of analysis, 1876 patients were operated on for a fistula. Of these, 82 (4.4%) had a horseshoe extension. The majority (72%) were male and the median age was 46 (17–84) years. The primary tract was high transsphincteric in 90% of cases and the primary opening was posterior in 65% of cases. The location of the horseshoe extension was posterior in 66% of cases with spread in the deep perianal space in 62%. In all, 71% were cryptoglandular and 24% were seen in Crohn’s disease (20). Of the 62 non‐Crohn’s patients previous treatment was common and included surgery (42), antibiotics alone (41) and non‐steroidal anti‐inflammatory drugs (21). Conclusion Horseshoe extension in anal fistula is uncommon. With Crohn’s disease excepted, the majority had had previous treatment.  相似文献   
57.
ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease.  相似文献   
58.
Clinical practice guidelines are intended to serve as a bridge between the decision levels and the sources of knowledge, giving decision makers the best synthesis of scientific evidence and an analysis of context, to provide elements of judgement and to transfer scientific knowledge into clinical practice. However, the actual impact on health care is variable and effectiveness in changing medical practice, moderate. Qualitative and quantitative studies show that most primary care physicians consider that the guides are a valuable source of advice and training and a kind of improving the quality of healthcare. However, they underline its rigidity, the difficulty to apply to individual patients and that their main goal is to reduce healthcare costs. In Spain, there are several experiences as GuíaSalud in developing clinical practice guidelines aimed specifically at primary care. However, the proper implementation of a clinical practice guideline includes not only the quality and thoroughness of the evidence, but the credibility of professionals and organizations and other contextual factors such as characteristics of patients, providers and organizations or systems. An important step in future research is to develop a better theoretical understanding of organizational change that is required for management and professionals to give appropriate guidance to the implementation of the clinical practice guidelines.  相似文献   
59.
Inhibition and potentiation of platelet function by lysolecithin   总被引:1,自引:0,他引:1  
  相似文献   
60.
Tayek JA  Atienza VJ 《Endocrine》1995,3(5):315-318
This study characterizes the hypothalamic-pituitary-adrenal axis function in patients with sepsis syndrome now known as systemic inflammatory response syndrome (SIRS). One hundred and thirteen patients with SIRS had their pituitary-adrenal axis tested with the use of a 250 μg IV ACTH stimulation test. No patient received corticosteroids prior to the ACTH stimulation test. Serum cortisol concentrations were measured prior to and 30 and 60 min after ACTH administration. 26% of the patients had bacteremia, 22% bacteruria, 22% AIDS, 17% renal failure, 15% diabetes, 13% severe liver disease, 8% GI bleed, 4% pancreatitis, 3% trauma and 1% classical Addison's disease. Several patients had more than one disorder. The overall mortality was 28%. Multivariate analysis identified that both the baseline cortisol concentration and delta cortisol concentration were significant indicators of mortality. Despite the fact that mortality was double in the bacteremic patients, the baseline cortisol concentrations were similar to the non-bacteremic patients (25.4 ± 1.9vs 25.1 ± 2.5 μg/dl). The only cortisol abnormality noted in the bacteremic patients was a significantly smaller delta cortisol response to ACTH (14.7 ± 2.2vs 18.9 ± 1.2 μg/dl;P<0.05). These data imply that bacteremic processes may alter the adrenal responsiveness to intravenous ACTH administration. Understanding the pathophysiological disturbances responsible for an impaired adrenal reserve may identify new treatment strategies for patients with bacteremia.  相似文献   
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