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41.
The chemical composition of total alkaloids from leaves and roots of Guiera senegalensis was investigated. Three beta-carboline alkaloids were purified: in addition to harman and tetrahydroharman, known in roots and leaves, harmalan (dihydroharman) was isolated for the first time from roots of Guiera senegalensis. Guieranone A, a naphthyl butenone, was also purified from leaves and roots. The in vitro antiplasmodial activity and the cytotoxicity of extracts and pure compounds were evaluated. Each total alkaloid extract and beta-carboline alkaloids presented an interesting antiplasmodial activity associated with a low cytotoxicity. Harmalan was less active than harman and tetrahydroharman. Guieranone A showed a strong antiplasmodial activity associated with a high cytotoxicity toward human monocytes. Its cytotoxicity was performed against two cancer cell lines and normal skin fibroblasts in order to study its anticancer potential: guieranone A presented a strong cytotoxicity against each cell strains. Finally, we evaluated the potent synergistic antimalarial interaction between Guiera senegalensis and two plants commonly associated in traditional remedies: Mitragyna inermis and Pavetta crassipes. Three associations evaluated were additive. A synergistic effect was shown between total alkaloids extracted from leaves of Guiera senegalensis and those of Mitragyna inermis. This result justified the traditional use of the plants in combination to treat malaria.  相似文献   
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The purpose of this study was to explore the knowledge, attitudes and barriers to use of postpartum care service among rural communities in Uganda. Study was a part of a larger reproductive health evaluation project, and was cross-sectional in nature utilizing qualitative research methods using the narrative inquiry. Two matched rural communities were used in this study; Semuto in Luwero district, and Lwamaggwa in Rakai district. Fifty key informants who were purposefully selected from each study site were interviewed. They included community leaders, political leaders, health care providers, women leaders and community members. One-on-one interviews were conducted with key community informants using an interview guide. The purpose of the interview was explained to each participant, and written informed consent was obtained before the start of the interview. Respondents were allowed to express their views, opinions and observations on several health issues including postpartum health care services. There was a low level of knowledge about postpartum care services among the respondents of the two communities. There was lack of awareness about postpartum care and it’s benefits. The main barriers to use of services were; misconceptions regarding the importance of postpartum care, distance to health facilities, poverty, and health system factors notably; poor facilities, lack of essential drugs, and poor attitudes of health workers. In the effort to improve reproductive health care services, there is an urgent need to improve postpartum services, and make them more accessible and user friendly. The training of providers at all levels is essential, in addition to educating families on the importance of postpartum care services.Sarah K. Nabukera is Senior Lecturer Community Health, (currently on study leave at the University of Alabama at Birmingham); Charles Muchunguzi, Lecturer Development Studies; Francis Bajunirwe; Vincent K. Batwala; and Edgar M. Mulogo, Lecturers Community Health, all at Mbarara University of Science and Technology, Mbarara, Uganda. Souleymane Barry was Chief of Party DISH II Project, Kampala, Uganda.Kim Witte is Senior Program Evaluation Officer, Center for Communication Programs, Johns Hopkins University, Baltimore, Maryland; Celeste Farr, Assistant Professor Department of Communications, North Carolina State University, Raleigh, North Carolina; and Hamisu M Salihu Associate Professor Maternal and Child Health, University of Alabama at Birmingham, USA.This project was funded by USAID # 617-A-00-00-00-0000-00.  相似文献   
43.
Polyacrylamide gel electrophoresis allowing study of rotavirus genome was applied to 213 faecal specimens from children with acute gastroenteritis living in Dakar area, Senegal. We were able to define an electrophoretype in 41 cases (19.2%). Five different RNA electrophoretypes were shown. The electrophoretype 4 was the most frequent (41.4%). "Long" and "short" electrophoretic migration patterns were found in 36 and 5 cases, respectively. We found 34.1% of electrophoretypes in children aged from 6 to 11 months. The electrophoretypes 1, 3, 4 and 5 have co-circulated throughout the study period (March 1985 to August 1986). No mixed infections were found. Large surveys of this type would allow to evaluate the general situation in Senegal in urban areas as well as in rural areas.  相似文献   
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Measurement of viral load in plasma remains the best marker for the follow-up of antiretroviral therapy. However, its use is limited in developing countries due to the lack of adequate facilities and equipment, and cryopreservation of plasma during storage and transportation. Practical and reliable methods adapted to field conditions for the collection, transportation and accurate measurement of HIV-1 viral load are needed for the optimum use of antiretroviral therapy in resource-limited countries. This study evaluated the use of dried blood spots (DBS) for the real-time quantitation of HIV-1 RNA levels with the NucliSENS EasyQ((R)) HIV-1 assay (bioMérieux, Lyon, France) under field conditions in Senegal (Africa). Dried blood spots and plasma from 41 patients living in suburban Dakar were used for determination of HIV-1 RNA concentrations and stability at 37 degrees C. Analysis was performed at the Dakar University Hospital laboratory. Extraction was done with the bioMérieux NucliSENS((R)) miniMAGtrade mark, and real-time detection was done with the bioMérieux NucliSENS((R)) EasyQ system. HIV-1 RNA concentrations in plasma were compared with concentrations in dried blood spots after 8 and 15 days at 37 degrees C. The study showed a strong concordance in RNA levels between plasma and dried blood spots, which appear to be very stable over time with no apparent degradation observed after 2 weeks at 37 degrees C (mean difference 0.065logIU/ml). These results suggest that the use of dried blood spots in combination with the NucliSENS EasyQ HIV-1 assay is well adapted for HIV-1 RNA level monitoring in centralized laboratories in developing countries.  相似文献   
46.
Despite efforts to reduce malaria morbidity and mortality, drug-resistant parasites continue to evade control strategies. Recently, emphasis has shifted away from control and toward regional elimination and global eradication of malaria. Such a campaign requires tools to monitor genetic changes in the parasite that could compromise the effectiveness of antimalarial drugs and undermine eradication programs. These tools must be fast, sensitive, unambiguous, and cost-effective to offer real-time reports of parasite drug susceptibility status across the globe. We have developed and validated a set of genotyping assays using high-resolution melting (HRM) analysis to detect molecular biomarkers associated with drug resistance across six genes in Plasmodium falciparum. We improved on existing technical approaches by developing refinements and extensions of HRM, including the use of blocked probes (LunaProbes) and the mutant allele amplification bias (MAAB) technique. To validate the sensitivity and accuracy of our assays, we compared our findings to sequencing results in both culture-adapted lines and clinical isolates from Senegal. We demonstrate that our assays (i) identify both known and novel polymorphisms, (ii) detect multiple genotypes indicative of mixed infections, and (iii) distinguish between variants when multiple copies of a locus are present. These rapid and inexpensive assays can track drug resistance and detect emerging mutations in targeted genetic loci in P. falciparum. They provide tools for monitoring molecular changes associated with changes in drug response across populations and for determining whether parasites present after drug treatment are the result of recrudescence or reinfection in clinical settings.  相似文献   
47.
Introduction : The science presented at the 21st International AIDS Conference in Durban, South Africa, in July 2016, addressed the state of the field across basic, clinical, prevention, law and policy and implementation science. Methods and Results : The AIDS response has seen remarkable achievements in scientific advances, in translation of those advances into prevention, treatment and care for affected individuals and communities, and in large scale implementation – reaching 18 million people with antiviral therapy by mid‐year 2016. Yet incident HIV infections in adults remain stubbornly stable and are increasing in some regions and among adolescents and adults in some key populations, challenging current science, policy and programming. There have been important advances in both preventive vaccines and in cure research, but both areas require ongoing investment and innovation. Clinical research has flourished with new agents, regimens, delivery modes and diagnostics but has been challenged by aging and increasingly complex patient populations, long‐term adherence challenges, co‐infections and co‐morbidities, and unresolved issues in TB management and epidemic control. It is an extraordinary period of innovation in prevention, yet the promise of new tools and combination approaches have yet to deliver epidemic HIV control. Conclusions : Proven interventions, most notably pre‐exposure prophylaxis, PrEP, have been limited in rollout and impact. Treatment as prevention has the promise to improve clinical outcomes but remains uncertain as a prevention tool to reduce population‐level HIV incidence. The improvement of legal, policy and human rights environments for those most at risk for HIV acquisition and most at risk for lack of access to essential services; sexual and gender minorities, sex workers of all genders, people who inject drugs, and prisoners and detainees remain among the greatest unmet needs in HIV/AIDS. Failure to do better for these individuals and communities could undermine the HIV response.  相似文献   
48.
A study of 312 untreated and 303 HAART-initiating patients to determine whether HAART is related to sexual risk taking in C?te d'Ivoire. At enrollment, unprotected sex was higher among untreated patients (P = 0.014). During follow-up, risk taking was similar (P = 0.484) as a result of an increase in unprotected sex among treated patients (from 20.4 to 30.1%, P < 0.0001) and stability among untreated patients (from 27.0 to 28.8%, P = 0.301). HAART appeared to be associated with sexual risk taking.  相似文献   
49.
SETTING: Two teaching hospitals in Dakar, Senegal, a West African country with a low prevalence of human immunodeficiency virus (HIV) infection. OBJECTIVE: To determine whether patients with HIV-associated pulmonary tuberculosis have fewer acid-fast bacilli (AFB) in their sputum as assessed by routine microscopy, and to correlate the findings with systematically obtained clinical, radiographic and laboratory variables. DESIGN: Prospective study from November 1995 to October 1996 of 450 consecutive patients diagnosed with pulmonary tuberculosis. RESULTS: Tuberculosis was diagnosed in 380 patients (84.4%) by positive bacteriology, in 61 (13.6%) by a favorable response to anti-tuberculosis chemotherapy, and in nine (2.0%) by the presence of a miliary radiographic pattern. Forty (8.9%) patients were HIV-seropositive. AFB-negative smears were found in 14/40 (35.0%) of the HIV-seropositive patients with pulmonary tuberculosis compared with 71/410 (17.3%) of the seronegative patients (risk ratio [RR] = 2.02, 95% confidence interval [CI] 1.26-3.24, P = 0.01). Multivariate analysis revealed that AFB smear negativity was associated with absence of cavitation (P = 0.002), lack of cough (P = 0.005), the presence of HIV seropositivity (P = 0.02), a CD4+ cell count above 200/mm3 (P = 0.02), and age over 40 years (P = 0.03). CONCLUSIONS: Compared with HIV-seronegative patients with pulmonary tuberculosis, seropositive patients in Dakar, Senegal, are more likely to have negative sputum-AFB smears. This phenomenon has now been observed in seven of eight sub-Saharan African countries with varying HIV seroprevalence from which reports are available.  相似文献   
50.
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