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EDITORIAL COMMENT: We accepted this case report for publication not only because of its rare anecdotal interest, which is considerable, but also since it will warn readers that rectal bleeding in pregnancy may result from an abdominal pregnancy. It is strange that the ultrasonograph seems not to have identified the calcification as a fetus although we are not told that the latter was macerated or misshapen. The editor has never seen or heard of an ectopic pregnancy causing rectal erosion and bleeding although he has reported a primary abdominal pregnancy in which the placenta was implanted on the peritoneum of the pouch of Douglas posteriorly (A); this woman presented at 23 weeks' gestation when retroplacental haemorrhage resulted in a haematoma that bulged into the vagina causing acute urinary retention. One wonders why the placenta did not erode the anterior rectal wall in this more advanced case of primary placental implantment in the pouch of Douglas.
Summary: A rare case of abdominal pregnancy, causing massive rectal bleeding due to invasion of the rectal wall by the placenta, is reported.  相似文献   
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BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
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The World Health Organization (WHO) listed the air pollution in Ulaanbaatar (Mongolia) among the top 5 cities with the worst air quality in the world. Air quality in the winter season reaches highs of 750 μg/m3 for daily average fine particulates (PM) due to increased coal combustion and lower mixing heights (<200 m), coupled with the city’s geography surrounded by mountains, which further restricts the vertical and horizontal dispersion of the pollutants. The annual average concentrations in 2010–2011 ranged 136?±?114 μg/m3 (the WHO guideline for fine PM is 10 μg/m3). The single largest source of particulate pollution in Ulaanbaatar is coal and biomass combustion in households and heat-only boilers, followed by power plants. In this paper, we present sector-specific emissions for 2010 accounting for 62,000 tons of fine PM, 55,000 tons of sulfur dioxide, and 89,000 tons of nitrogen oxide emissions. The inventory is spatially disaggregated at 0.01° resolution on a GIS platform for use in a chemical transport model (ATMoS). The modeled concentrations for the urban area ranged 153?±?70 μg/m3, when overlaid on gridded population, resulted in estimated 1,000–1,500 premature deaths per year due to outdoor air pollution. This study also highlights the linkages between indoor and outdoor air pollution. In these harsh temperate conditions, with 50 % of the emissions originating from Ger households, they are as big a health risk for indoor air quality as they are for outdoor air quality. Any intervention improving combustion efficiency or providing clean fuel for these stoves will have a combined benefit for indoor air quality, outdoor air quality, and climate policy. The analysis shows that aggressive pollution control measures are imperative to protect the population in Ulaanbaatar from excess exposure levels, and implementation of control measures like the introduction of heat efficient stoves, clean coal for heating boilers, and urban transport planning will result in significant health benefits, which surpass any costs of institutional, technical, and economic interventions.  相似文献   
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A total of 1,000 kilns producing 3.5 billion bricks and consuming 0.85 million tons of coal per year resulted in an estimated 2,200 to 4,000 premature deaths and 0.2 to 0.5 million asthma attacks per year in the Greater Dhaka region. In this paper, the emission reductions and health cost savings are presented for moving to cleaner brick manufacturing technologies for the districts of Gazipur, Savar, Dhamrai, Rupganj, Manikganj, Kaliganj, and Narayanganj. A summary of various technologies and feasibility of these technologies based on lessons learnt from the pilots is discussed. We explored three “what-if” scenarios through 2020 for better energy efficiency, lower coal consumption, and lower emission rates, under which the total health cost savings are estimated to range between USD12 million annually for short-term implementation and up to 55 million annually for long-term implementation. Between 2015 and 2020, the cumulative health cost savings could range between USD126 and 234 million, which clearly outweigh any cost of capital investment necessary for the technology change. An improvement in energy efficiency will result in USD1.8 to 3.0 million per year in coal savings, which will accrue to the kiln owners collectively, and these savings will pay back the capital investment within 3–4 years, in addition to the health cost savings for the city inhabitants. Hence, the entrepreneurs have all the social, environmental, and economic incentives to adopt cleaner technologies. A major gap at the regulatory level is in building awareness for the entrepreneurs and setting up an incentive structure to implement this transition, which is being addressed by an advisory committee by the Government of Bangladesh responsible for the revision of the Brick Burning Act of 1989 and related legislations.  相似文献   
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BackgroundBalloon mitral valvotomy (BMV) is a safe and an effective treatment in patients with symptomatic rheumatic mitral stenosis. This study was conducted to validate the importance of assessing the morphology of mitral valve commissures by transoesophageal echocardiography and thereby predicting the outcome after balloon mitral valvotomy [BMV].Materials and methodsStudy consisted of 100 patients with symptomatic mitral stenosis undergoing BMV. The Commissural Morphology and Wilkins score were assessed by transoesophageal echocardiography. Both the commissures (anterolateral and posteromedial) were scored individually according to whether non-calcified fusion was absent (0), partial (1), or extensive (2) and calcification (score 0) and combined giving an overall commissural score of 0–4. Outcome of BMV was correlated with commissural score and Wilkins score.ResultsThe commissural score and outcome after BMV correlated significantly. 66 of 70 patients (94%) with a commissural score of 3–4 obtained a good outcome compared with only six (20%) patients of 30 with a commissural score of 0–2 (positive and negative predictive accuracy 94% and 80%, respectively, p < 0.001). Increase in 2DMVA post BMV was more in patients with higher commissural score (score of 3–4). Wilkins score <8 usually predicts a good outcome but even in patients with Wilkins score >8 a commissural score >2 predicts a 50% chance of a good result.ConclusionsA higher commissural score predicts a good outcome after BMV hence it can be concluded that along with Wilkins score, commissural morphology and score should be assessed with TOE in patients undergoing BMV.  相似文献   
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ObjectiveTo evaluate the wound healing effect of aqueous extract of Crotalaria verrucosa (C. verrucosa) in rats.MethodsThree wound models including incision, excision and dead space wounds were used in this study. The parameters studied were breaking strength in incision models, granulation tissue dry weight, breaking strength and hydroxyproline content in dead space wounds, percentage of wound contraction and period of epithelialization in excision wound model.ResultsTwo doses of the extract with and without dexamethasone showed significant increases in mean hydroxyproline, total protein content and dry weight of granulation tissue but it was higher with dose 800 mg/kg comparing with the control. The dexamethasone treated group showed a significant (P<0.001) reduction in the wound breaking strength when compared to control group in incision type of wound model. Coadministration of C. verrucosa with dexamethasone significantly (P<0.001) increased the breaking strength compared to the dexamethasone treated only group. In excision wound model, the percentage of the wound contraction was significantly (P<0.01) increased by two doses of test extract on all the days except the lower dose which exhibited only on 12 th, 16 th days of drug treatment and it also reversed the dexamethasone suppressed wound contraction. It significantly (P <0.001) reduced the time required for epithelialization and reversed the epithelialization delaying effect of dexamethasone (P<0.001).ConclusionsC. verrucosa was found to possess significant wound healing property. This was evident by decrease in the period of epithelialization, increase in the rate of wound contraction, skin breaking strength, and granulation tissue dry weight content. Hence C. verrucosa could be a good wound healing agent.  相似文献   
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