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21.
Objective Diabetes is associated with pulmonary tuberculosis (TB), possibly due to impaired immunity, and diabetes may exacerbate the clinical manifestations of TB. Our aim was to assess the role of diabetes in the clinical manifestations of TB. Methods We studied 1250 patients with pulmonary TB in an urban population in a cross‐sectional study in Tanzania. All participants were tested for diabetes and HIV co‐infection, and TB culture intensity was assessed. Levels of white blood cells, haemoglobin, acute phase reactants, CD4 count and HIV viral load were measured, and a qualitative morbidity questionnaire was used to identify the prevalence of disease‐related symptoms. Results Tuberculosis patients with diabetes had a higher neutrophil count (B 0.5 × 109 cells/l, 95% CI 0.2; 0.9, P = 0.001) than non‐diabetic TB patients. Serum C‐reactive protein (B 18.8 mg/l, CI 95% 8.2; 29.4, P = 0.001) and alpha‐1‐acid glycoprotein (B 0.2 g/l, CI 95% 0.03; 0.3, P = 0.02) were similarly higher in patients with diabetes. Diabetes did not affect culture intensity or HIV status, but self‐reported fever was three times higher among participants with diabetes than in those without diabetes (OR 2.9, CI 95% 1.5; 5.7, P = 0.002). Conclusion Diabetes is associated with small changes in the manifestations of TB, but may have little clinical significance.  相似文献   
22.
Objectives To describe trends in voluntary counselling and testing (VCT) use and to assess whether high‐risk and infected individuals are receiving counselling and learning their HIV status in rural Tanzania. Methods During two rounds of linked serological surveys (2003–2004 and 2006–2007) with anonymous HIV testing among adults, VCT was offered to all participants. The crude and adjusted odds ratios for completing VCT in each survey were calculated to compare uptake by demographic, behavioural and clinical characteristics, stratified by sex. Repeat testing patterns were also investigated. Results The proportion of participants completing VCT increased from 10% in 2003–2004 to 17% in 2006–2007, and among HIV‐infected persons from 14% to 25%. A higher proportion of men than women completed VCT in both rounds, but the difference declined over time. Socio‐demographic and behavioural factors associated with VCT completion were similar across rounds, including higher adjusted odds of VCT with increasing numbers of sexual partners in the past 12 months. The proportion having ever‐completed VCT reached 26% among 2006–2007 attendees, with repeat testing rates highest among those aged 35–44 years. Among 3923 participants attending both rounds, VCT completion in 2006–2007 was 17% among 3702 who were HIV negative in both rounds, 19% among 124 who were HIV infected in both rounds and 22% among 96 who seroconverted between rounds. Conclusion VCT services are attracting HIV‐infected and high‐risk individuals. However, 2 years after the introduction of antiretroviral therapy, the overall uptake remains low. Intensive mobilisation efforts are needed to achieve regular and universal VCT use.  相似文献   
23.
The subsidisation of mosquito nets has been widely used to increase ownership in countries where malaria represents a public health problem. However, an important question that has not been addressed empirically is how far net subsidy programmes increase ownership above the level that would have prevailed in the absence of the subsidy (i.e., incremental ownership). This study addresses that gap by investigating the impact of a large‐scale mosquito net voucher subsidy––the Tanzania National Voucher Scheme (TNVS)––on short‐term demand for unsubsidised commercial nets, estimating a household demand model with nationally representative household survey data. The results suggest that, despite the TNVS using a categorical targeting approach that did not discriminate by wealth, it still led to a large increase in incremental ownership of mosquito nets, with limited evidence of displacement of unsubsidised sales. Although no evidence is found of an additional TNVS voucher decreasing the number of unsubsidised sales in the same period, results indicate that an additional TNVS voucher reduced the probability of purchasing any unsubsidised net in the same period by 14%. The findings also highlight the critical role played by social learning or campaign messaging in increasing mosquito net ownership.  相似文献   
24.
Setting: Health care facilities in Dar es Salaam, Pwani, and Arusha, Tanzania.Objective: To assess health care worker (HCW) knowledge and practices 1 year after specialized training in childhood tuberculosis (TB).Design: Using a standardized survey, we interviewed a convenience sample of HCWs providing both general and specialized care to children.Results: We interviewed 117 HCWs in TB clinics, maternal and child health clinics, human immunodeficiency virus (HIV) clinics, out-patient departments, and pediatric in-patient wards at 12 facilities. A total of 81 HCWs (62% of nurses, 74% of clinicians) reported having attended the national childhood TB training course. Most HCWs responded correctly to questions on childhood TB diagnosis, treatment, and TB-HIV co-management, regardless of training history. Most HCWs reported that they routinely obtain chest radiographs, HIV testing, and a TB contact history when evaluating children for TB. Less than half of HCWs reported routinely obtaining sputum for mycobacterial culture or performing a tuberculin skin test. Three times as many trained as untrained HCWs reported having ever prescribed isoniazid preventive therapy (IPT) to a child (P < 0.05).Conclusion: In general, levels of childhood TB knowledge were high and practices were in accordance with national guidance. Specific gaps in diagnosis, treatment and use of IPT were identified for future focused training.  相似文献   
25.
The control of childhood anaemia in malaria holoendemic areas is a major public health challenge for which an optimal strategy remains to be determined. Malaria prevention may compromise the development of partial immunity. Regular micronutrient supplementation has been suggested as an alternative but its effectiveness remains unsettled. We therefore conducted a randomised placebo-controlled intervention trial with 207 Tanzanian children aged 5 months to 3 years on the efficacy of supervised supplementation of low-dose micronutrients including iron (Poly Vi-Sol with iron) three times per week, with an average attendance of >/= 90%. The mean haemoglobin (Hb) level increased by 8 g/l more in children on supplement (95% CI 3-12) during the 5-month study. All age groups benefited from the intervention including severely anaemic subjects. The mean erythrocyte cell volume (MCV) increased but Hb in children >/= 24 months improved independently of MCV and no relation was found with hookworm infection. The data therefore suggest that micronutrients other than iron also contributed to Hb improvement. In the supplement group of children who had received sulfadoxine-pyrimethamine (SP) treatment, the mean Hb level increased synergistically by 22 g/l (95% CI 13-30) compared to 7 g/l (95% CI 3-10) in those without such treatment. Supplementation did not affect malaria incidence. In conclusion, micronutrient supplementation improves childhood anaemia in malaria holoendemic areas and this effect is synergistically enhanced by temporary clearance of parasitaemia.  相似文献   
26.
27.
Objectives

Docosahexaenoic (DHA) and arachidonic (AA) acids are important for neurodevelopment. We investigated the relation between erythrocyte (RBC) DHA and AA contents and neurological development, by assessment of General Movements (GMs), in populations with substantial differences in fish intakes.

Methods

We included 3-month-old breastfed infants of three Tanzanian tribes: Maasai (low fish, n = 5), Pare (intermediate fish, n = 32), and Sengerema (high fish, n = 60); and a Dutch population (low–intermediate, fish, n = 15). GMs were assessed by motor optimality score (MOS) and the number of observed movement patterns (OMP; an MOS sub-score). RBC-DHA and AA contents were determined by capillary gas chromatography.

Results

We found no between-population differences in MOS. OMP of Sengerema infants (high fish) was higher than OMP of Dutch infants (low–intermediate fish). MOS related to age. OMP related positively to infant age (P < 0.001) and RBC-DHA (P = 0.015), and was unrelated to ethnicity and RBC-AA.

Discussion

The positive relation between RBC-DHA and the number of observed movement patterns of 3-month old infants might reflect the connection of DHA with motor development.  相似文献   

28.
Super-resistant Plasmodium falciparum threatens the effectiveness of sulfadoxine–pyrimethamine in intermittent preventive treatment for malaria during pregnancy. It is characterized by the A581G Pfdhps mutation on a background of the double-mutant Pfdhps and the triple-mutant Pfdhfr. Using samples collected during 2004–2008, we investigated the evolutionary origin of the A581G mutation by characterizing microsatellite diversity flanking Pfdhps triple-mutant (437G+540E+581G) alleles from 3 locations in eastern Africa and comparing it with double-mutant (437G+540E) alleles from the same area. In Ethiopia, both alleles derived from 1 lineage that was distinct from those in Uganda and Tanzania. Uganda and Tanzania triple mutants derived from the previously characterized southeastern Africa double-mutant lineage. The A581G mutation has occurred multiple times on local Pfdhps double-mutant backgrounds; however, a novel microsatellite allele incorporated into the Tanzania lineage since 2004 illustrates the local expansion of emergent triple-mutant lineages.  相似文献   
29.
We conducted a seroprevalence survey among 500 healthy adult donors at Zanzibar National Blood Transfusion Services. Dengue virus IgG seroprevalence was 50.6% and independently associated with age and urban residence. These data will aid in building a surveillance, preparedness, and response plan for dengue virus infections in the Zanzibar Archipelago.Key words: dengue, seroprevalence, Zanzibar, viruses, vector-borne infections  相似文献   
30.
Single-dose mass drug administration of azithromycin (AZT) is underway to eliminate trachoma worldwide. Studies in Ethiopia showed a reduction in all-cause childhood deaths after administration. To examine the effect of single-dose AZ MDA on prevalent malaria infections in a large prospective cohort of children and parents in Dodoma Province, Tanzania, we quantified the temporal prevalence of malaria parasitemia by real-time PCR for 6 months after single-dose AZT. In the first month after treatment but not in subsequent months, Plasmodium falciparum infections were reduced by 73% (95% CI 43%–89%) in treatment versus control villages and differences remained significant (p = 0.00497) in multivariate models with village-level random effects. Genetic sequencing of P. falciparum ribosomal L4 protein showed no mutations associated with AZT resistance. AZT mass drug administration caused a transient, 1-month antimalarial effect without selecting for P. falciparum ribosomal L4 resistance mutations in a region with a 10-year history of treating trachoma with this drug.  相似文献   
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