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81.
Non‐consumer researchers collaborating with consumer researchers can benefit from greater relevance of research and improved congruence between research processes and health policy. As with all research collaborations, such partnerships are both constrained and facilitated by research ecosystems. However, it seems that collaborations with consumer researchers are impacted in particular ways by the research ecosystem. Drawing on ecological systems theory, this study aims to improve understandings of how ecological structures impact collaborations between non‐consumer and consumer researchers. Interviews were conducted with 11 non‐consumer researchers from a range of mental health disciplines about their experiences collaborating with consumer researchers. One theme developed through analysis of the data set related to the research ecosystem. Data from this theme were extracted and discursively analysed using the principles of discursive psychology. Findings emphasize distinct factors that influence collaborations at each level of the ecosystem, encompassing both local research culture and broader research systems. Findings suggest that external pressures (such as deadlines for funding applications, or bureaucratic processes) from the broader ecosystemic levels need to be challenged at the local collaboration level. Non‐consumer researchers might support collaborations through, for instance, working to create enhanced flexibility in research timelines, or making time for relationship building, thus fostering more meaningful collaborations.  相似文献   
82.
RESEARCH QUESTIONS: Couples undergoing IVF in Switzerland may have embryos in excess of their clinical need that they can donate to human embryonic stem cell research. Thus a new practice has emerged in Switzerland when IVF treatment and embryonic stem cell research come into contact. This interface needs to be investigated from an ethical-legal point of view to facilitate a fair informed choice process for the couples involved.METHODS: Ethical analysis, patient perspectives elaboration. Interdisciplinary approach that draws on the research project JESP-ELSI (joint embryonic stem cell research project--ethical legal and societal implications). RESULTS AND CONCLUSIONS: To facilitate the donation of surplus embryos to human embryonic stem cell research, we propose a procedure of informed choice that fits to the current Swiss legal situation. In addition we identify problems within the current legal setting and suggest methods to improve communication at the interface between IVF and embryonic stem cell research from an ethical perspective.  相似文献   
83.
Colonic motor activity was initiated by infusions of bile salts into the caecum or rectum of the anaesthetized rabbit. Primary bile acids were examined proximally and distally in the colon and elicited marked motor responses. Sinc dihydroxy bile acids are known to be potent inhibitors of electrolyte and water absorption in the colon, the secondary bile acid deoxycholic acid, the dihydroxyl compound most related to cholic acid which is the main bile acid in the rabbit, was examined distally and was also active, but to a lesser extent than cholic acid conjugates in this species. In man, a relationship was found between the faecal bile acid excretion and colonic motility: the introduction of bile acids directly into the human sigmoid colon and rectum also stimulated colonic motility. In man, the dihydroxy compound chenodeoxycholic acid was slightly more active than conjugates of cholic acid.  相似文献   
84.
STUDY OBJECTIVES: The noninvasive assessment and monitoring of airway inflammation could be important in respiratory disease. The pH of exhaled breath condensate (EBC) is a promising marker. Although pH has been measured in the EBC of adults with inflammatory airway diseases, no study has measured this in children. DESIGN: This study aimed to assess whether there is a change in pH in the EBC of children with cystic fibrosis (CF) and asthma, and to try to determine whether pH could be used as a marker of airway inflammation. Furthermore, the relationships among EBC pH, severity of disease, and oxidative stress were studied. PATIENTS AND METHODS: We studied 20 children with CF (mean [+/- SEM] age, 7 +/- 3 years), 20 children with asthma (mean age, 7 +/- 2 years), and 15 age-matched healthy children (mean age, 7 +/- 2 years). The pH of EBC was measured using a pH meter. MEASUREMENTS AND RESULTS: Lower pH values were observed in the EBC of children with CF and asthma compared to control subjects (mean pH, 7.23 +/- 0.03 and 7.42 +/- 0.01 vs 7.85 +/- 0.02, respectively). Furthermore, relationships among EBC pH, severity of asthma, and the presence of an infective exacerbation of CF was found. There was a negative correlation between exhaled pH and exhaled leukotriene B(4) concentrations (r = -0.5; p < 0.005). CONCLUSION: We conclude that the measurement of EBC pH may be useful in the evaluation of airway inflammation in children with asthma and CF.  相似文献   
85.
G M Fullarton  S Falconer  A Campbell    W R Murray 《Gut》1992,33(4):550-553
Although sphincter of Oddi dysfunction is a recognised cause of post cholecystectomy pain, the control mechanisms involved in sphincter of Oddi function are poorly understood. Pharmacological relaxation of the sphincter of Oddi may have a beneficial effect particularly in sphincter of Oddi dysfunction where basal sphincter pressure is high. The aim of this study was to investigate the effects of calcium channel blockade (nicardipine) and synthetic cholecystokinin (ceruletide) on sphincter of Oddi pressures. Nineteen patients (median age 49 years; range 21-75) attending for routine endoscopic retrograde cholangiopancreatographic (ERCP) examination were studied. No patients with evidence of sphincter of Oddi dysfunction were included in the study. Each patient was randomly allocated to receive a three minute intravenous infusion of nicardipine 3 mg (six) ceruletide 5 ng/kg (seven) or placebo (six). Endoscopic biliary manometry was done with recording of basal sphincter of Oddi pressures, sphincter of Oddi phasic wave amplitude and frequency before and after intravenous infusions. In the nicardipine group patients showed a decrease in both basal and phasic amplitude sphincter of Oddi pressure (mm Hg) from the preinfusion values (mean (SEM)) of 24.7 (3.6) and 112.3 (13.4) to 12.9 (2.9) (p less than 0.01) and 89.9 (12.4) (p less than 0.03) after infusion respectively. Ceruletide produced a decrease in sphincter of Oddi phasic wave frequency (c/min) from 3.4 (0.3) before infusion to 2.6 (0.5) after infusion (p less than 0.05). We conclude that nicardipine effectively decreases sphincter of Oddi pressure. This drug may therefore be of value in the treatment of sphincter of Oddi dysfunction where raised sphincter pressures are thought to be the primary pathogenic feature.  相似文献   
86.

Background

Conflicting evidence exists on whether smoking acts as an effect modifier of the association between APOE genotype and risk of coronary heart disease (CHD).

Methods and results

We searched PubMed and EMBASE to June 11, 2013 for published studies reporting APOE genotype, smoking status and CHD events and added unpublished data from population cohorts. We tested for presence of effect modification by smoking status in the relationship between APOE genotype and risk of CHD using likelihood ratio test.In total 13 studies (including unpublished data from eight cohorts) with 10,134 CHD events in 130,004 individuals of European descent were identified. The odds ratio (OR) for CHD risk from APOE genotype (ε4 carriers versus non-carriers) was 1.06 (95% confidence interval (CI): 1.01, 1.12) and for smoking (present vs. past/never smokers) was OR 2.05 (95%CI: 1.95, 2.14). When the association between APOE genotype and CHD was stratified by smoking status, compared to non-ε4 carriers, ε4 carriers had an OR of 1.11 (95%CI: 1.02, 1.21) in 28,789 present smokers and an OR of 1.04 (95%CI 0.98, 1.10) in 101,215 previous/never smokers, with no evidence of effect modification (P-value for heterogeneity = 0.19). Analysis of pack years in individual participant data of >60,000 with adjustment for cardiovascular traits also failed to identify evidence of effect modification.

Conclusions

In the largest analysis to date, we identified no evidence for effect modification by smoking status in the association between APOE genotype and risk of CHD.  相似文献   
87.
Preoperative fasting aims to increase patient safety by reducing the risk of adverse events during general anaesthesia. However, prolonged fasting may be associated with dehydration, hypoglycaemia and electrolyte imbalance as well as patient discomfort. We aimed to examine compliance with the current best practice guidelines in a large surgical unit and to identify areas for improvement. Adult patients undergoing elective and emergency general, orthopaedic, gynaecology and vascular surgery procedures in the Royal Infirmary of Edinburgh were surveyed over a 3-month period commencing November 2011. A standardised questionnaire was used to collect information on the duration of preoperative fasting and the advice administered by medical and nursing staff. 292 patients were included. Median fast from solids was 13.5 h for elective patients (IQR 11.5–16) and 17.38 h for emergency patients (IQR 13.68–28.5 h). Similarly, the median fast from fluids was 9.36 h for elective patients (IQR 5.38–12.75 h) and 12.97 h for emergency patients (IQR 8.5–16.22 h). The instructions that elective patients received contributed to prolonged fasting times. The median fast for elective patients fully compliant with fasting advice would be 10 h for solids (IQR 8.75–12 h) and 6.25 h (IQR 3.83–9.25 h) for clear fluids. Elective patients fasted for longer than recommended confirming that clinical practice is slow to change. The use of universal fasting instructions and patient choice are factors that unnecessarily prolong preoperative fasting, which however appears to be multifactorial. Service improvement by abbreviation of the observed fasting periods will rely on targeted staff education and effective clinical communication by provision of written information for both elective and emergency surgical patients. The routine use of preoperative nutritional supplements may need to be re-examined when further evidence is available.  相似文献   
88.
89.

Purpose

To determine a reference background urinary thallium level; to compare urinary thallium data from workers to this background level; to investigate factors affecting these levels and whether creatinine correction is appropriate.

Methods

Urine samples from non-occupationally exposed people (n = 273, from 113 individuals) and workers (n = 896, from 447 individuals) were analysed for thallium by ICP-MS. A reference background level was calculated, defined as the 95th percentile value of a non-occupationally exposed population. Worker data were divided into two subsets: thallium workers (those who work directly with thallium or its compounds) and general workers; and compared to the background level. Bayesian linear mixed effects modelling was used to investigate factors affecting urinary thallium concentration and the efficacy of creatinine correction for the determination of urinary thallium.

Results

The reference background urinary thallium level is 0.27 μmol/mol creatinine (creatinine-corrected) or 0.40 μg/l (uncorrected). Median values were 0.11 μmol/mol creatinine or 0.17 μg/l for non-occupationally exposed people, 0.12 μmol/mol creatinine or 0.20 μg/l for general workers and 0.19 μmol/mol creatinine or 0.41 μg/l for thallium workers. Variation was lower in creatinine-corrected models. Nine per cent of samples from general workers and 39 % of samples from thallium workers exceeded the creatinine-corrected background level. By 2010, 90 % of all workers had urinary thallium levels below the 95th percentile reference background level.

Conclusions

Urinary thallium concentrations were higher in thallium workers than non-occupationally exposed people and general workers. Creatinine correction is appropriate.  相似文献   
90.
Oxidative stress is considered an important factor that promotes cell death in response to a variety of pathophysiological conditions. This study investigated the antioxidant properties of allicin, the principle ingredient of garlic, on preventing oxidative stress-induced injury. The antioxidant capacities of allicin were measured by using 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay and hydrogen peroxide (H2O2)-induced cell damage on H9c2 cardiomyoblasts. Allicin (0.3–10?μM) pre-incubation could concentration-dependently attenuate the intracellular reactive oxygen species (ROS) increase induced by H2O2 on H9c2 cells. It could also protect H9c2 cells against H2O2-induced cell damage. However, the DPPH free radical scavenging activity of allicin was shown to be low. Therefore, it is believed that the protective effect of allicin on H9c2 cells could inhibit intracellular ROS production instead of scavenging extracellular H2O2 or free radicals. For the observed protective effect on H9c2 cells, allicin might also be effective in reducing free radical-induced myocardial cell death in ischemic condition.  相似文献   
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