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The water footprint of humanity   总被引:10,自引:0,他引:10  
This study quantifies and maps the water footprint (WF) of humanity at a high spatial resolution. It reports on consumptive use of rainwater (green WF) and ground and surface water (blue WF) and volumes of water polluted (gray WF). Water footprints are estimated per nation from both a production and consumption perspective. International virtual water flows are estimated based on trade in agricultural and industrial commodities. The global annual average WF in the period 1996–2005 was 9,087 Gm3/y (74% green, 11% blue, 15% gray). Agricultural production contributes 92%. About one-fifth of the global WF relates to production for export. The total volume of international virtual water flows related to trade in agricultural and industrial products was 2,320 Gm3/y (68% green, 13% blue, 19% gray). The WF of the global average consumer was 1,385 m3/y. The average consumer in the United States has a WF of 2,842 m3/y, whereas the average citizens in China and India have WFs of 1,071 and 1,089 m3/y, respectively. Consumption of cereal products gives the largest contribution to the WF of the average consumer (27%), followed by meat (22%) and milk products (7%). The volume and pattern of consumption and the WF per ton of product of the products consumed are the main factors determining the WF of a consumer. The study illustrates the global dimension of water consumption and pollution by showing that several countries heavily rely on foreign water resources and that many countries have significant impacts on water consumption and pollution elsewhere.  相似文献   
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Background

Multidrug resistant tuberculosis(MDR-TB) is becoming a major threat to tuberculosis control programs in Ethiopia.

Objectives

To determine risk factors of MDR-TB patients in Amhara National Regional State, Ethiopia.

Methods

Case-control study was conducted from May 2013 to January 2014. Resistance to rifampicin and isoniazid were done molecularly using line probe assay. TB patients infected with MDR-M.tuberculosis and non MDR-M.tuberculosis strain were considered as cases and controls, respectively. Data was collected using structured questionnaire with face to face interview. Patients'' clinical record review was also done.Multivariate analysis was computed to determine the risk factors of MDR-TB.

Results

A total of 153 MDR-TB and equal number of non MDR-TB patients'' participated in the study. Patients who had TB treatment failure (AOR=13.5,CI=2.69–70), cavitations on chest x-ray (AOR=1.9,CI=1.1–3.38) and contact with MDR-TB patients (AOR=1.4,CI=0.19–0.39) were more likely to be MDR-TB patients. Low monthly income (AOR=1.1,CI=0.34–0.47),alcohol consumption (AOR=1.5,CI=0.2–0.98) and young age (AOR=2.9,CI=1.07–7.68) were the other risk factors of MDR-TB.

Conclusions

TB treatment failure, cavitation on chest X-ray, contact with MDR-TB patients and low socioeconomic status were important risk factors for development of MDR-TB. Therefore, strict adherence to directly observed therapy, appropriate management of TB patients and advice on the value of nutrients are helpful to control the spreading of MDR-TB.  相似文献   
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Carissa edulis (forssk) vahl (Apocynaceae) is used traditionally for the treatment of headache, chest complaints, rheumatism, gonorrhoea, syphilis, rabies and as a diuretic. In the present study, the diuretic activity of different extracts of Carissa edulis was investigated. The diuretic activity of the different extracts of Carissa edulis in a dose range of 50-1000 mg/kg was assessed orally in rats using hydrochlorothiazide as a standard drug. The root bark maceration extract showed no effect on the urine output up to a dose of 1000 mg/kg, while the root bark soxhlet extract produced a significant increase (P < 0.05) in urine output at a dose of 1000 mg/kg. The root wood maceration and root wood soxhlet extracts produced a significant increase in urine output at a dose of 50 mg/kg, with a P-value of <0.05. Urinary electrolyte excretion was also affected by the extracts: the root bark soxhlet extract increased urinary excretion of sodium, potassium and chloride ions; root wood maceration extract increased excretion of sodium and potassium, while root wood soxhlet extract increased excretion of potassium ion. These findings support the traditional use of Carissa edulis as a diuretic agent.  相似文献   
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AIMS: To describe the epidemiological development of a rural Ethiopian population from 1987 to 2004 in terms of mortality and associated sociodemographic factors. METHODS: A rural population comprising 10 communities was defined in 1987 and has since been followed by means of regular household visits. After an initial census, births, deaths and migration events were recorded, together with key background factors, on an open cohort basis. Over 97,000 individuals were observed during a total of over 700,000 person years. RESULTS: The initial population of 28,614 increased by an average of 3.64% annually to 54,426 from 1987 to 2004, and also grew older on average. Birth and mortality rates fell, but were still subject to short-term variation due to external factors. Overall mortality was 13.5 per 1000 person years. Increasing mortality in some adult age groups was consistent with increasing AIDS-related deaths, but a new local hospital in 2002 may have contributed to later falls in overall mortality. Sex, age group, time period, literacy, water source, house ownership and distance to town were all significantly associated with mortality differentials. CONCLUSIONS: This population has undergone a complex epidemiological transition during a generation. Detailed long-term surveillance of this kind is essential for describing such processes. Many factors that significantly affect mortality cannot be directly controlled by the health sector and will only improve with general development.  相似文献   
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