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71.
The health effects of organophosphorus (OP) pesticides on cholinesterase (ChE) activities were assessed among 81 pest control workers from Northern Omo State Farm (Ethiopia), following the occupational use of Chlorpyrifos 25 and 48% ULV and Profenifos 250 EC/ULV. Plasma ChE (PChE) and erythrocyte ChE (AChE) activities were determined electrometrically before and after pesticide exposure. Plasma alkaline phosphatase (AP) and glutamic pyruvic transaminase (GPT) values were estimated colorimetrically. Risk factors of pesticide poisoning and related occupational factors were assessed following the WHO recommendations. The mean PChE and AChE activities determined after pesticide exposures were significantly lower than the pre-exposure values (P < 0.05); 16% and 40% of the pest control workers had PChE and AChE levels below 50% of the pre-exposure values, respectively. The mean plasma AP and GPT values were found to be within the recommended normal limits. No significant difference in either of the ChE activities was observed between the spray men and the pest assessors, although the former were believed to have frequent contact with the concentrated OP formulations. Risk factors of pesticide poisoning such as workers ignorance about the toxicity of pesticides, poor personal hygiene and total absence or improper use of personal protective devices were prevalent. Measures that should be considered to minimize the problem in the farm population are recommended.  相似文献   
72.

Background

Reliable data on causes of death form the basis for building evidence on health policy, planning, monitoring, and evaluation. In Ethiopia, the majority of deaths occur at home and civil registration systems are not yet functional. The main objective of verbal autopsy (VA) is to describe the causes of death at the community or population level where civil registration and death certification systems are weak and where most people die at home without having had contact with the health system.

Methods

Causes of death were classified and prepared based on the International Classification of Diseases (ICD-10). The cause of a death was ascertained based on an interview with next of kin or other caregivers using a standardized questionnaire that draws information on signs, symptoms, medical history, and circumstances preceding death. The cause of death, or the sequence of causes that led to death, is assigned based on the data collected by the questionnaire. The complete VA questionnaires were given to two blinded physicians and reviewed independently. A third physician was assigned to review the case when disagreements in diagnosis arose.

Results

Communicable diseases (519 deaths [48.0%]), non-communicable diseases (377 deaths [34.8%]), and external causes (113 deaths [10.4%]) were the main causes of death between 2007 and 2013. Of communicable diseases, tuberculosis (207 deaths [19.7%]), HIV/AIDS (96 deaths [8.9%]) and meningitis (76 deaths [7.0%]) were the most common causes of death.

Conclusion

Tuberculosis, HIV/AIDS, and meningitis were the most common causes of deaths among adults. Death due to non-communicable diseases showed an increasing trend. Increasing community awareness of infections and their interrelationships, tuberculosis case finding, effective local TB programs, successful treatment, and interventions for HIV are supremely important.
  相似文献   
73.
74.
Objective:To evaluate the berries of Phytolacca dodecundra(P.dodecandra) for its effect on Histoplasma cupsulatum var.farciminosum(HCF) and for the treatment of cases of epizootic lymphangitis(ELi.Methods:Samples were collected from un-ruptured nodules of cases of EL at Debre Zeit and Akaki(central Ethiopia).Mycologieal culture and isolation of HCF were performed at the Akliln Lemma Institute of Pathobiology.Phytochemical screening was done for n-butanol extract of P.dodecandra to delect alkaloids,saponins,phenolic compounds and flavonoids.The minimum inhibitory concentrations(MICs) and minimum fungicidal concentrations(MFCs) ol aqueous and n-butanol extracts of P.dodecandra against FICF were determined by agar dilution assay.For the in vivo trial.5%simple ointment was prepared from n-butanol extract and applied topically to 24(twelve early and twelve moderate) cases of F.L.Results:Phytochemical screening showed that n-butanol extract ol P.dodecandra was positive lor alkaloids.saponins and phenolic compounds but negative for flavonoids.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.039%-0.078%) and(0.625%-1.250%),respectively.The MFCs of n-butanol and aqueous extracts of P.dodecandra were(0.078%t-0.156%)and(1.250%-2.500%),respectively.The MIC and MFC of ketoconazole(positive control) was(1.200×10~(-5)%-2.500×10~(-5)%) and(5.000× 10~(-5)%-1.000×10~(-4)%),respectively while growth was observed on free medium(negative control).From the total of 24 treated cases of EL,14(58.3%) responded lo treatment;however,10(41.7%) did not respond to treatment.There was no significant difference in the degree of response to treatment between early and moderate cases(χ~2=0.086:P=0.408.Conclusions:It can be concluded that n-butanol extract of P.dodecandra demonstrates antifungal effects while the aqueous extract shows no antifungal activity.  相似文献   
75.
76.
BACKGROUND: Although several surveys investigating the epidemiology of herpes simplex virus type 2 (HSV-2) infection using type-specific immunologic assays have been carried out in Africa, none has examined the risk factors for HSV-2 infection in a representative sample from an urban adult population. GOALS: To estimate the prevalence of HSV-2 infection in the adult population of Addis Ababa, Ethiopia, and to identify risk factors for HSV-2 infection. STUDY DESIGN: Two cross-sectional surveys, one community-based (June to September 1996, n = 506) and one factory-based (February to November 1997, n = 657), were conducted. Samples were tested for HSV-2 immunoglobulin G antibodies using type-specific enzyme-linked immunoassays (ELISA). RESULTS: In the community-based survey, HSV-2 prevalence increased with age until 25 years, then leveled off at 50% in both genders. The same independent predictors of HSV-2 infection were identified in both genders: older age, higher lifetime number of sexual partners, positive HIV serology, and positive Treponema pallidum hemagglutination serology. CONCLUSIONS: This study confirmed the high prevalence of HSV-2 infection among adults in an African urban population and its association with HIV infection. Prevention of HSV-2 and other sexually transmitted infections through partner reduction and condom use should be encouraged.  相似文献   
77.
78.
High ethanol tolerance is an exquisite characteristic of the yeast Saccharomyces cerevisiae, which enables this microorganism to dominate in natural and industrial fermentations. Up to now, ethanol tolerance has only been analyzed in laboratory yeast strains with moderate ethanol tolerance. The genetic basis of the much higher ethanol tolerance in natural and industrial yeast strains is unknown. We have applied pooled-segregant whole-genome sequence analysis to map all quantitative trait loci (QTL) determining high ethanol tolerance. We crossed a highly ethanol-tolerant segregant of a Brazilian bioethanol production strain with a laboratory strain with moderate ethanol tolerance. Out of 5974 segregants, we pooled 136 segregants tolerant to at least 16% ethanol and 31 segregants tolerant to at least 17%. Scoring of SNPs using whole-genome sequence analysis of DNA from the two pools and parents revealed three major loci and additional minor loci. The latter were more pronounced or only present in the 17% pool compared to the 16% pool. In the locus with the strongest linkage, we identified three closely located genes affecting ethanol tolerance: MKT1, SWS2, and APJ1, with SWS2 being a negative allele located in between two positive alleles. SWS2 and APJ1 probably contained significant polymorphisms only outside the ORF, and lower expression of APJ1 may be linked to higher ethanol tolerance. This work has identified the first causative genes involved in high ethanol tolerance of yeast. It also reveals the strong potential of pooled-segregant sequence analysis using relatively small numbers of selected segregants for identifying QTL on a genome-wide scale.  相似文献   
79.

Background

Moringa stenopetala, Baker f. (Moringaceae) is used for food and medicine in Southern Ethiopia.

Objective

To substantiate the hypotensive effect of M. stenopetala in vivo and in vitro.

Methods

An in vivo experiment was carried out on male guinea pigs anaesthetized with pentobarbital. The arterial blood pressure was recorded from a carotid artery filled with heparinized saline via an arterial cannula connected to a pressure transducer. For the in vitro experiment the descending thoracic aorta was removed and kept moistened in Krebs-Henseleit solution and then mounted in a 20ml tissue bath maintained at 37°C and bubbled with a mixture of 95% oxygen and 5% carbon dioxide.

Results

Crude aqueous leaf extract of M. stenopetala caused significant fall in systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial blood pressure (MABP) at doses of 10, 20, 30 and 40 mg/kg in normotensive anaesthetized guinea pigs (n = 12). The effect might have been mediated by non-autonomic nervous system as the effect is not altered by atropine and propranolol. The extract also caused significant dose and time dependent inhibition of K+ induced contraction on guinea pig aorta.

Conclusion

M.stenopetala has blood pressure lowering effect substantiating the use of the plant in traditional medicine.  相似文献   
80.
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