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71.
The Blue Nile (Abay) Highlands of Ethiopia are characterized by significant interannual climate variability, complex topography and associated local climate contrasts, erosive rains and erodible soils, and intense land pressure due to an increasing population and an economy that is almost entirely dependent on smallholder, low-input agriculture. As a result, these highland zones are highly vulnerable to negative impacts of climate variability. As patterns of variability and precipitation intensity alter under anthropogenic climate change, there is concern that this vulnerability will increase, threatening economic development and food security in the region. In order to overcome these challenges and to enhance sustainable development in the context of climate change, it is necessary to establish climate resilient development strategies that are informed by best-available Earth System Science (ESS) information. This requirement is complicated by the fact that climate projections for the Abay Highlands contain significant and perhaps irreducible uncertainties. A critical challenge for ESS, then, is to generate and to communicate meaningful information for climate resilient development in the context of a highly uncertain climate forecast. Here we report on a framework for applying ESS to climate resilient development in the Abay Highlands, with a focus on the challenge of reducing land degradation.  相似文献   
72.
Ethiopia has become warmer over the past century and human induced climate change will bring further warming over the next century at unprecedented rates. On the average, climate models show a tendency for higher mean annual rainfall and for wetter conditions, in particular during October, November and December, but there is much uncertainty about the future amount, distribution, timing and intensity of rainfall. Ethiopia's low level of economic development, combined with its heavy dependence on agriculture and high population growth rate make the country particularly susceptible to the adverse effects of climate change. Nearly 90% of Ethiopia's population lives in the Highlands, which include the critical Blue Nile (Abay) Highlands--a region that holds special importance due to its role in domestic agricultural production and international water resources. A five year study of climate vulnerability and adaptation strategies in communities of Choke Mountain, located in the center of the Abay Highlands, has informed a proposed framework for enhancing climate resilience in communities across the region. The framework is motivated by the critical need to enhance capacity to cope with climate change and, subsequently, to advance a carbon neutral and climate resilient economy in Ethiopia. The implicit hypothesis in applying a research framework for this effort is that science-based information, generated through improved understanding of impacts and vulnerabilities of local communities, can contribute to enhanced resilience strategies. We view adaptation to climate change in a wider context of changes, including, among others, market conditions, the political-institutional framework, and population dynamics. From a livelihood perspective, culture, historical settings, the diversity of income generation strategies, knowledge, and education are important factors that contribute to adaptive capacities. This paper reviews key findings of the Choke Mountain study, describes the principles of the climate resilience framework, and proposes an implementation strategy for climate resilient development to be applied in the Abay Highlands, with potential expansion to agricultural communities across the region and beyond.  相似文献   
73.
74.
Dietary pantothenic acid supplementation was investigated to re-evaluate National Research Council recommendation level of 10 ppm on broilers growth rate, feed consumption, feed efficiency, survivability, nitrogen-corrected metabolizable energy, and pectoralis major (breast muscle) pantothenic acid concentration as well as carcass parameters including dressing percentage, liver, gizzard, abdominal fat pad percentage and specific gravity. Treatments evaluated included: 1. basal corn and soybean meal diet containing 10 ppm pantothenic acid supplemented to National Research Council recommendations; 2. as treatment 1 plus 20 ppm pantothenic acid; and 3. as treatment 1 plus 40 ppm pantothenic acid. Increasing dietary pantothenic acid supplementation beyond 10 ppm did not (P>.1) influence growth rate, feed consumption, feed efficiency, survivability, and nitrogen-corrected metabolizable energy. Dietary pantothenic acid supplementation beyond National Research Council recommendation failed to impact any of the carcass parameters measured, but elevated (P<.05) pectoralis major pantothenic acid concentration. The data suggests that the National Research Council recommendation of 10 ppm dietary pantothenic acid is satisfactory for growth but increasing broilers dietary pantothenic acid enhances carcass nutritional value.  相似文献   
75.
We describe our experience of the HIV seroprevalence among blood donors in a rural general hospital in Ethiopia during an eight-year period (January 1998-December 2006). From 3305 blood donors screened, 51 (1.4%) were positive for HIV antibodies.  相似文献   
76.
BACKGROUND: Carica papaya family Caricaceacae is one of the herbal remedies, which has recently become a subject of research focus. It is used in traditional medicine for variety of purposes in treating infectious and noninfectious diseases. OBJECTIVE: The objective of this study was to assess the antibacterial effect of papaya seed extract against bacterial pathogens isolated from wound, urine and stool. METHODS: This analytical experimental study was conducted in Jimma University, School of Medical Laboratory Technology, Microbiology laboratory between February to March 2005. The antibacterial activity of methanol extract of papaya seed was investigated against specific pathogenic bacteria isolated from wound, urine and stool by an agar dilution technique and the crude preparation was assessed by an agar diffusion technique. The growth or inhibition of control strains of Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa as well as the clinical isolates of these bacteria were determined in growth media. RESULTS: Results obtained in this study indicate that the minimum inhibitory concentration of papaya seed extract for 50% of the test bacteria was 18.38mg/ml and for S. typhi the MIC was at 11.8 mg/ml of extract. However, the growth inhibitory effect of papaya seed extract was not observed for P. aeruginosa up to 26.25 mg /ml of extract. Even though, the minimum bactericidal concentration is higher than the minimum inhibitory concentration of papaya seed extract (13.13 mg/ml, 11.8 mg/ml respectively) against S. typhi control and clinical isolates, the minimum bactericidal concentration for 50% of the tested bacteria was found to be similar with the minimum inhibitory concentration of the test bacteria, CONCLUSION: Papaya seed could be used as an effective antibacterial agent for the tested organisms. Nevertheless, preclinical studies including invivo animal models and clinical trial on the effect of the seed are essential before advocating large-scale therapy.  相似文献   
77.

Background

The initiation of highly active antiretroviral therapy (HAART) plays a significant role in the clinical management of HIV infected people by preventing morbidity and mortality. This benefit becomes, the most terrible when treatment failure develops. Thus, this research aims to assess the prevalence and associated factors of treatment failure among HIV/AIDS patients on HAART attending University of Gondar Referral Hospital Northwest Ethiopia.

Results

Patients on ART with a minimum of 6?months and up to 12?years of treatment were being enrolled. The prevalence of treatment failure, immunological failure and virological failure among people living with HIV/AIDS attending University of Gondar referral hospital were 20.3, 13.2, and 14.7%, respectively. Patients who had no formal education (Adjusted odds ratio (AOR): 3.8; 95% CI, 1.05–13.77), primary level education (AOR: 4.2; 95% CI, 1.16–15.01) and duration on ART <?6?years (AOR: 2.1; 95%CI, 1.12–3.81) were a significant risk factor. However, initial adult regimen D4T?+? 3TC+ EFV (AOR: 0.025; 95% CI, 0.002–0.36), AZT +3TC?+?NVP (AOR: 0.07; 95% CI, 0.01–0.71), AZT?+? 3TC?+?EFV (AOR: 0.046; 95% CI, 0.004–0.57) andTDF+3TC?+?EFV (AOR: 0.04; 95% CI, 0.004–0.46) were significantly protective for treatment failure.

Conclusions

Timely and early identification of associated factors and monitoring antiretroviral therapy treatment failure should be done to enhance the benefit and to prevent further complication of the patients. It is preferable to initiate ART using any one of the following ART regimens: AZT +3TC?+?NVP, AZT?+?3TC?+?EFV and TDF?+?3TC?+?EFV to prevent treatment failure. Since the prevalence of this treatment failure and its associated factor may be different from other ART centers and community in Ethiopia, further national representative institutional based cross-sectional researches are needed across all ART centers of Ethiopia in order to determine the prevalence of treatment failure and its associated factors.
  相似文献   
78.
In this paper, we describe a case of an otherwise healthy 51 year old Caucasian male who presented with extensive venous thrombosis and a large retroperitoneal hepatoma without active bleeding. On imaging he was found to have focal calciifcation in the juxtarenal IVC and extensive thrombosis of the iliofemoral and femoropoliteal veins as well as the infrarenal IVC. Despite treating the patient with pharmacomechanical thrombectomy and anticoaguation, he passed away likely due to a new pulmonary embolism. According to the literature available to us, IVC calcification is a rare finding in adults and has been associated with an increased incidence of recurrent deep vein thrombosis and pulmonary embolism. While long term anticoagulation has been recommended for patients with recurrent venous thromboembolism (VTE), there is no expert consensus or societal guidelines for the treatment VTE in the setting of IVC calcification, specifically, regarding pharmacomechanical Vs. surgical thrombectomy [1]. Furthermore, no recommendations currently exist regarding whether expectant management Vs. prophylactic anticoagulation is appropriate. In conclusion, disease specific management guidelines by professional medical societies may be needed regarding the utility and appropriateness of pharmacomechanical thrombectomy Vs. surgical thrombectomy for symptomatic cases as well as expectant management Vs. prophylactic anticoagulation for asymptomatic cases in the setting of IVC calcification.  相似文献   
79.
80.
INTRODUCTION: The continuous improvement of gene transfer technologies has broad implications for stem cell biology, gene discovery, and gene therapy. Although viral vectors are efficient gene delivery vehicles, their safety, immunogenicity and manufacturing challenges hamper clinical progress. In contrast, non-viral gene delivery systems are less immunogenic and easier to manufacture. AREAS COVERED: In this review, we explore the emerging potential of transposons in gene and cell therapy. The safety, efficiency, and biology of novel hyperactive Sleeping Beauty (SB) and piggyBac (PB) transposon systems will be highlighted for ex vivo gene therapy in clinically relevant adult stem/progenitor cells, particularly hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), myoblasts, and induced pluripotent stem (iPS) cells. Moreover, efforts toward in vivo transposon-based gene therapy will be discussed. EXPERT OPINION: The latest generation SB and PB transposons currently represent some of the most attractive systems for stable non-viral genetic modification of primary cells, particularly adult stem cells. This paves the way toward the use of transposons as a non-viral gene therapy approach to correct hereditary disorders including those that affect the hematopoietic system. The development of targeted integration into "safe harbor" genetic loci may further improve their safety profile.  相似文献   
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