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11.
BackgroundThe risk of co-infection with Schistosoma haematobium and S. mansoni and the potential harmful effect on morbidity and control is enhanced by the overlapping distribution of both species in sub-Saharan Africa. Despite the reported high endemicity of both species in Nigeria, studies on the spread and effect of their mixed infection are limited. Therefore, a cross-sectional survey was conducted among school children in two communities in South-west Nigeria to investigate the prevalence of mixed human schistosome infection, intensity, and possible ectopic egg elimination.MethodsUrine and stool samples were collected from consenting school children in Ilie and Ore communities of Osun State, Nigeria. Schistosoma haematobium eggs were detected in urine using the urine filtration technique, while S. mansoni eggs were detected in stool using the Kato–Katz thick smear technique.ResultsThe study enrolled 466 primary and secondary school children (211; 45.3% males vs. 255; 54.7% females; mean age 11.6 ± 3.16 years). The overall prevalence of schistosomiasis was 40% (185/466), with 19% (89/466) recording single S. haematobium infection while 9% (41/465) had a single S. mansoni infection. The geometric mean egg count for S. haematobium was 189.4 egg/10ml urine; 95% CI: range 115.9–262.9, while for S. mansoni, it was 115.7 epg; 95% CI: range 78.4–152.9. The prevalence of ectopic S mansoni (S. mansoni eggs in urine) was 4.7%, while no ectopic S. haematobium (S. haematobium eggs in stool) was recorded. Mixed infection of S. haematobium/S. mansoni had a prevalence of 9.5% (44/466). More females (54.5%) presented with S. haematobium/S. mansoni co-infection. For both parasites, males had higher infection intensity, with a significant difference observed with S. haematobium (p = 0.0004). Hematuria was significant in individuals with single S. haematobium infection (p = 0.002), mixed ectopic S. haematobium/S. mansoni (p = 0.009) and mixed S. haematobium/S. mansoni/ectopic S. mansoni (p = 0.0003).ConclusionsThese findings suggest the probability of interspecific interactions between S. haematobium and S. mansoni. Scaling up of mass administration of praziquantel and control measures in the study areas is highly desirable.  相似文献   
12.
Ten healthy human volunteers were subjected to progressive lower body negative pressure (LBNP) to the onset of cardiovascular collapse to compare the response of noninvasively determined skin and fat corrected deep muscle oxygen saturation (SmO2) and pH to standard hemodynamic parameters for early detection of imminent hemodynamic instability. Muscle SmO2 and pH were determined with a novel near infrared spectroscopic (NIRS) technique. Heart rate (HR) was measured continuously via ECG, and arterial blood pressure (BP) and stroke volume (SV) were obtained noninvasively via Finometer and impedance cardiography on a beat-to-beat basis. SmO2 and SV were significantly decreased during the first LBNP level (-15 mmHg), whereas HR and BP were late indicators of impending cardiovascular collapse. SmO2 declined in parallel with SV and inversely with total peripheral resistance, suggesting, in this model, that SmO2 is an early indicator of a reduction in oxygen delivery through vasoconstriction. Muscle pH decreased later, suggesting an imbalance between delivery and demand. Spectroscopic determination of SmO2 is noninvasive and continuous, providing an early indication of impending cardiovascular collapse resulting from progressive reduction in central blood volume.  相似文献   
13.
The concentrations of copper, iron, and zinc in the major organs of Wistar albino (Rattus norvegicus) and wild black rats (Rattus rattus) were measured by means of atomic absorption spectroscopy. The copper levels in the kidneys and liver of the Wistar albino rats (WARs) were significantly higher (p<0.05) than in the wild black rats (WBRs). There were no significant differences in the concentrations of zinc in the liver, lungs, kidneys, and brain between the two study groups, but zinc was significantly higher in the spleen (p<0.05) and lower in the heart (p<0.05) of WAR, compared to WBRs. Iron was significantly higher (p<0.05) in the heart and spleen of WBRs, compared to WARs. There were no extreme differences in the organ concentrations of trace elements between the two species, but, cumulatively, the WARs tend to have higher metallic concentrations in their system than the WBRs. The potential of these differences on the experimental results should not be overlooked and will serve as basis to further consider the complex interrelationships of these animals in their microenvironments and macroenvironments.  相似文献   
14.
A study was conducted to examine the protectability of nine Nigerian medicinal plants against Callosobruchus maculatus at an ambient temperature of 28?±?2?°C and relative humidity of 70?±?5%. The nine plants used were dried and milled into fine powder before application. Among the nine plant powders used, Zanthoxylum zanthoxyloides effected highest mortality rate of 73.40 and 100% at 5% (wt/wt) concentration within two and three days of application, respectively. The effect of this plant at this level of concentration was significantly (p?<?0.05) different from other plants. However, all the plant powders effected high mortality rate as they all achieved more than 50% beetle mortality within four days of application at 20% (wt/wt) concentration. Only the powder of Z. zanthoxyloides at 10% (wt/wt) concentration was able to achieve 0% adult emergence, 0% seed damage and 100% damage reduction. Moreover, powder of Z. zanthoxyloides, Aristolochia ringens and Colocasia esculenta at 20% (wt/wt) was also able to prevent the emergence of adult C. maculatus, prevent seed damage and achieve 100% damage reduction. All the powders had low weevil perforation index when compared to the control which had above 50% weevil perforation index. At all levels of concentration, the effect of the powders was significantly (p?<?0.05) different from the control. However, Z. xanthoxyloides appeared to be the most effective; therefore, the effective utilisation of Z. xanthoxyloides as a botanical pesticide could minimise the use of hazardous chemicals in stored product pest control since it is of a botanical source.  相似文献   
15.
Chronic myeloid leukemia (CML) is characterized by the reciprocal translocation t(9;22)(q34;q11.2) which fuses the ABL1 oncogene on chromosome 9 with the BCR gene on chromosome 22. It is the BCR/ABL protein that drives the neoplasm and the ABL/BCR is not necessary for the disease. In the majority of CML cases, the BCR/ABL fusion gene is cytogenetically recognizable as a small derivative chromosome 22(der 22), which is known as the Philadelphia (Ph) chromosome. However, approximately 2-10% of patients with CML involve cryptic or complex variant translocations with deletions on the der(9) and/or der(22) occuring in roughly 10-15% of CML cases. Fluorescence in situ hybridization (FISH) analysis can help identify deletions and complex or cryptic rearrangements. Various BCR/ABL FISH probes are available, which include dual color single fusion, dual color extra signal (ES), dual color dual fusion and tri color dual fusion probes. To test the utility of these probes, six patients diagnosed with CML carrying different complex variant Ph translocations were studied by G-banding and FISH analysis using the BCR/ABL ES, BCR/ABL dual color dual fusion, and BCR/ABL tricolor probes. There are differences among the probes in their ability to detect variant rearrangements, with or without accompanying chromoso me 9 and/or 22 deletions, and low level disease.  相似文献   
16.

Background

Patent medicine vendors (PMV) provide antimalarial treatment and care throughout Sub-Saharan Africa, and can play an important role in the fight against malaria. Their close-to-client infrastructure could enable lifesaving artemisinin-based combination therapy (ACT) to reach patients in time. However, systematic assessments of drug sellers’ performance quality are crucial if their role is to be managed within the health system. Lot quality assurance sampling (LQAS) could be an efficient method to monitor and evaluate PMV practice, but has so far never been used for this purpose.

Methods

In support of the Nigeria Malaria Booster Program we assessed PMV practices in three Senatorial Districts (SDs) of Jigawa, Nigeria. A two-stage LQAS assessed whether at least 80% of PMV stores in SDs used national treatment guidelines. Acceptable sampling errors were set in consultation with government officials (alpha and beta <0.10). The hypergeometric formula determined sample sizes and cut-off values for SDs. A structured assessment tool identified high and low performing SDs for quality of care indicators.

Findings

Drug vendors performed poorly in all SDs of Jigawa for all indicators. For example, all SDs failed for stocking and selling first-line antimalarials. PMV sold no longer recommended antimalarials, such as Chloroquine, Sulfadoxine-Pyrimethamine and oral Artesunate monotherapy. Most PMV were ignorant of and lacked training about new treatment guidelines that had endorsed ACTs as first-line treatment for uncomplicated malaria.

Conclusion

There is urgent need to regularly monitor and improve the availability and quality of malaria treatment provided by medicine sellers in Nigeria; the irrational use of antimalarials in the ACT era revealed in this study bears a high risk of economic loss, death and development of drug resistance. LQAS has been shown to be a suitable method for monitoring malaria-related indicators among PMV, and should be applied in Nigeria and elsewhere to improve service delivery.  相似文献   
17.
18.
Fields surveys were conducted to assess the incidence of commonly known legume viruses on cowpeas and weed hosts within and around the cowpeas farms in nine locations across the three agro-ecological zones of Nigeria. Of 315 cowpea leaf samples collected and tested for eight viruses, 69.5% were found to be infected. Bean common mosaic virus-blackeye mosaic (BCMV-BlCM), genus Potyvirus had the highest incidence (70%) and was also the most prevalent (78%). Cowpea aphid-borne mosaic virus (CABMV, genus Potyvirus) had 64% as incidence, incidence of Southern bean mosaic virus (SBMV, genus Sobemovirus) was 21%. Bean pod mosaic virus (BPMV, genus Comovirus) was detected in 1% of the samples tested. Cowpea mosaic virus (CPMV, genus Comovirus) was undetected. Other viruses tested included Cowpea mottle virus (CPMoV, genus Carmovirus), Cucumber mosaic virus (CMV, genus Cucumovirus), and Cowpea mild mottle virus (CPMMV, genus Carlavirus). Multiple virus infections were detected in 68.0% of the infected cowpea leaf samples. The combination of BCMV-BlCM and CABMV was the most common, occurring in 76.4% of all samples. Virus incidence in weeds around the cowpea plots was 2.5% (9 out of 356) whereas 1.5% (5 out of 332) of the weeds collected within the cowpea plots were infected. Some of the weeds infected were Chromoleana odorata, Centrosema sp., Thithonia diversifolia and Talinum triangulare.  相似文献   
19.
Changes in the composition of volatile compounds in cantaloupe melon (Cucumis melo L. var. reticulatus) as a result of UV induced stress were determined by gas chromatography-mass spectrometry (GC-MS). Several volatile ester compounds were present, of which twenty-seven were identified in fresh cut cantaloupe. Fruit exposure to UV light decreased the concentrations of most of the aliphatic esters by over 60% of the amounts present in the corresponding fresh cut fruit. Cyclic and acyclic terpenoids, including phytoalexin compounds beta-ionone, geranylacetone and terpinyl acetate, were also produced as a result of UV exposure for 15 and 60 min, respectively. beta-Ionone, when added to crushed cantaloupe (0.01% w/w) completely inhibited microbial growth in the fruit for 24 h at 20 degrees C. Geranylacetone and terpinyl acetate reduced the microbial population from 6.3x10(8) in the untreated control to 1.2x10(8) and 3.5x10(7) CFU/g respectively. The results indicate the potential use of UV induced stress for screening cantaloupe melon cultivars for disease resistance, and as a minimal processing method to extend the shelf life of fresh cut cantaloupe products.  相似文献   
20.
Hypoestoxide (HE) is a diterpene isolated from Hypoestes rosea (Acanthaceae), a plant indigenous to Nigeria. Previous studies demonstrated that HE exhibited potent anti-inflammatory and anti-cancer activities in well established animal models but weak in vitro activities in both the anti-inflammation and anti-cancer in vitro screening systems. We now report a similar observation in the in vitro and in vivo screening systems for antimalarial activity. The results indicate that while HE exhibits a relatively weak in vitro activity (IC(50) = 10 microM versus 0.11 microM for chloroquine) against different strains of cultured P. falciparum parasites, the dose of HE required to reduce parasitemia by 90% in Plasmodium berghei-infected mice, is much lower than standard antimalaria drugs (SD(90) = 250 microg/kg versus 5mg/kg for chloroquine). Furthermore, lower doses of HE were much more effective than higher doses in inhibiting parasite development. The implications of these findings are discussed.  相似文献   
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