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排序方式: 共有78条查询结果,搜索用时 15 毫秒
1.
Proximal femur articulation in Pliocene hominids   总被引:1,自引:0,他引:1  
The supposed "nonhuman anthropoid"-type femur head articular surface described for the Pliocene hominid specimen A.L.288-1 ("Lucy") by Stern and Susman in 1983 is present in significant numbers of modern human femora. This nonmetric skeletal trait was also found to be sex-related in modern human samples examined.  相似文献   
2.
A new hominid parietal from Bodo, Middle Awash Valley, Ethiopia   总被引:2,自引:0,他引:2  
A piece of left parietal of a Middle Pleistocene hominid, recovered from the Upper Bodo Sand Unit, in the Middle Awash, Ethiopia, is described anatomically and compared to Middle Pleistocene hominids and modern Homo sapiens. It bears several primitive features and has important implications for the original Bodo skull, found at the same stratigraphic level in the same area. The new fossil skull represents a different individual from the original Bodo skull.  相似文献   
3.
The mainly neotropical genus Calliandra Benth. (Leguminosae–Mimosoideae–Ingeae) is reported for the first time as native in continental Africa. There are two species known, C. gilbertii Thulin & Hunde sp. nov. in E Kenya and Somalia and C. redacta (J. H. Ross) Thulin & Hunde comb. nov. in South Africa near the Namibia border. On pollen morphological grounds they are supposed to be most related to certain neotropical species but the pollen does not agree entirely with any previously known group of the genus. The distribution of C gilbertii and C. redacta stresses the phytogeographical link between the arid zones of northern and southern Africa.  相似文献   
4.

Although GR2(SO4 2-) can be easily formed by abiotic synthesis, the biotic formation of hydroxysulphate as a single iron(II-III) mineral in microbial culture and its characterization was not achieved. This study was carried out to investigate the sole formation of GR2(SO4 2-) during the reduction of γ-FeOOH by a dissimilatory iron-respiring bacterium, Shewanella putrefaciens CIP 8040T. Reduction experiments were performed in a non-buffered medium devoid of organic compounds, with 25 mM of sulphate and with a range of lepidocrocite concentrations with H2 as the electron donor under nongrowth conditions. The resulting biogenic solids, after iron-respiring activity, were characterized by X-ray diffraction (XRD), transmission Mössbauer spectroscopy (TMS) and electron microscopy (SEM and TEM). The sulphate has been identified as the intercalated anion by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). In addition, the structure of this sulphate anion was discussed. Our experimental study demonstrated that, under H2 atmosphere, the biogenic solid was a GR2(SO4 2-), as the sole iron(II-III) bearing mineral, whatever the initial lepidocrocite concentration. The crystals of the biotically formed GR2(SO4 2-) are significantly larger than those observed for GR2(SO4 2-) obtained through abiotic preparation, < 15 μ m diameter as against 0.5–4 μm, respectively.  相似文献   
5.
Tuberculosis (TB) is one of the major public health and socio-economic issues in the 21st century globally. Assessment of TB treatment outcomes, and monitoring and evaluation of its risk factors in Directly Observed Treatment Short Course (DOTS) are among the major indicators of the performance of a national TB control program. Hence, this institution-based retrospective study was conducted to determine the treatment outcome of TB patients and investigate factors associated with unsuccessful outcome at Dilla University Referral Hospital, southern Ethiopia. Five years (2008 to 2013) TB record of TB clinic of the hospital was reviewed. A total 1537 registered TB patients with complete information were included. Of these, 942 (61.3%) were male, 1015 (66%) were from rural areas, 544 (35.4%) were smear positive pulmonary TB (PTB+), 816 (53.1%) were smear negative pulmonary TB (PTB-) and 177(11.5%) were extra pulmonary TB (EPTB) patients. Records of the 1537 TB patients showed that 181 (11.8%) were cured, 1129(73.5%) completed treatment, 171 (11.1%) defaulted, 52 (3.4%) died and 4 (0.3%) had treatment failure. The overall mean treatment success rate of the TB patients was 85.2%. The treatment success rate of the TB patients increased from 80.5% in September 2008-August 2009 to 84.8% in September 2012–May 2013. Tuberculosis type, age, residence and year of treatment were significantly associated with unsuccessful treatment outcome. The risk of unsuccessful outcome was significantly higher among TB patients from rural areas (AOR = 1.63, 95% CI: 1.21–2.20) compared to their urban counterparts. Unsuccessful treatment outcome was also observed in PTB- patients (AOR = 1.77, 95% CI: 1.26–2.50) and EPTB (AOR = 2.07, 95% CI: 1.28–3.37) compared to the PTB+ patients. In conclusion, it appears that DOTS have improved treatment success in the hospital during five years. Regular follow-up of patients with poor treatment outcome and provision of health information on TB treatment to patients from rural area is recommended.  相似文献   
6.
The flagellar calcium-binding protein (FCaBP) of the flagellated protozoan Trypanosoma cruzi associates with the flagellar membrane via its N-terminal myristate and palmitate moieties in a calcium-modulated, conformation-dependent manner. This mechanism of localization is similar to that described for neuronal calcium sensors, which undergo calcium-dependent changes in conformation, which modulate the availability of the acyl groups for membrane interaction and partner association. To test whether FCaBP undergoes a calcium-dependent conformational change and to explore the role of such a change in flagellar targeting, we first introduced point mutations into each of the two EF-hand calcium-binding sites of FCaBP to define their affinities. Analysis of recombinant EF-3 mutant (E151Q), EF-4 mutant (E188Q), and double mutant proteins showed EF-3 to be the high affinity site (Kd approximately 9 microM) and EF-4 the low affinity site (Kd approximately 120 microM). These assignments also correlated with partial (E188Q), nearly complete (E151Q), and complete (E151Q,E188Q) disruption of calcium-induced conformational changes determined by NMR spectrometry. We next expressed the FCaBP E151Q mutant and the double mutant in T. cruzi epimastigotes. These transproteins localized to the flagellum, suggesting the existence of a calcium-dependent interaction of FCaBP that is independent of its intrinsic calcium binding capacity. Several proteins were identified by FCaBP affinity chromatography that interact with FCaBP in a calcium-dependent manner, but with differential dependence on calcium-binding by FCaBP. These findings may have broader implications for the calcium acyl switch mechanism of protein regulation.  相似文献   
7.

Background

To assess and compare the prevalence, severity and prognosis of anti-TB drug induced hepatotoxicity (DIH) in HIV positive and HIV negative tuberculosis (TB) patients in Ethiopia.

Methodology/Principal Findings

In this study, 103 HIV positive and 94 HIV negative TB patients were enrolled. All patients were evaluated for different risk factors and monitored biochemically and clinically for development of DIH. Sub-clinical hepatotoxicity was observed in 17.3% of the patients and 8 out of the 197 (4.1%) developed clinical hepatotoxicity. Seven of the 8 were HIV positive and 2 were positive for HBsAg.

Conclusions/Significance

Sub-clinical hepatotoxicity was significantly associated with HIV co-infection (p = 0.002), concomitant drug intake (p = 0.008), and decrease in CD4 count (p = 0.001). Stepwise restarting of anti TB treatment was also successful in almost all the patients who developed clinical DIH. We therefore conclude that anti-TB DIH is a major problem in HIV-associated TB with a decline in immune status and that there is a need for a regular biochemical and clinical follow up for those patients who are at risk.  相似文献   
8.
9.
BackgroundEthiopia aims to eliminate lymphatic filariasis by 2020, through a dual approach of mass drug administration to interrupt transmission and morbidity control which includes making hydrocele surgery available in all endemic areas. Locating patients requiring surgery, providing high quality surgeries, and following up patients are all formidable challenges for many resource-challenged or difficult-to-reach communities. To date, hydrocele surgery in Ethiopia has only occurred when a patient has the knowledge, time and resources to travel to regional hospitals. Ethiopia tested the novel approach of using a surgical camp, defined as mobilizing, transporting, providing surgery at a static site, and following up of a large cohort of hydrocele patients within a hospital’s catchment area, to address delays in seeking and receiving care.Methodology and resultsHealth extension workers mobilized 252 patients with scrotal swelling from a list of 385 suspected hydrocele cases from seven endemic districts in the region of Beneshangul-Gumuz. Clinical health workers and surgeons confirmed 119 as eligible for surgery. Of 70 additional patients who self-referred, 56 were eligible for surgery. Over a two-week period at a regional hospital, 175 hydrocele excision surgeries were conducted. After discharge three days after surgery, trained clinical health workers followed up with the patients on Day 5, Day 8, Day 14 and 1st-month benchmarks with a randomized follow-up of a selection of patients conducted at 9–12 months. There were no post-operative complications upon discharge at Day 3 and 22, while minor complications occurred (12.6%) between Day 3 and one month. The 9–12 month follow-up found patients self-reported an improvement in quality of life, health and economic status.ConclusionA hydrocele surgery camp was effective at providing a large number of quality surgeries in a short time. Using peripheral health workers to mobilize and follow up patients helped address delays in seeking and receiving quality care. Mainstreaming patient mobilization and follow-up into a community health system could be effective in other countries. The camp’s results also influenced two regions in Ethiopia to change their policies in order to offer free hydrocele surgery (including patient transport, consultation, surgery, diagnostic tests and necessary medications).  相似文献   
10.
Adugna A 《Hereditas》2008,145(1):28-37
The experiment was carried out to estimate GEI in sorghum for grain yield using univariate and multivariate statistical approaches based on two sets of performance trials (T1 and T2). While T1 consisted of 15 genotypes and tested in 8 environments, T2 that consisted of 13 genotypes was carried out in 13 environments. Because the combined ANOVA of each trial revealed significant differences among the genotypes, among the environments and GEI, the five univariate stability estimates: CV(i), S(i)(2), W(i)(2), sigma(i)(2), b(i) and Sd(i)(2) were evaluated for ranking the genotypes. There was positive rank-correlation between CVi and S(i)(2) and among W(i)(2), sigma(i)(2), b(i). Sd(i)(2) had significant positive rank-correlation with sigma(i)(2) and bi in T1 but weak rank-correlation with the remaining parameters in both trials. The three types of univariate stability estimates and the only multivariate stability estimate, the AMMI analysis declared genotypes 2 and 5 to be the most stable in T1, but they gave quite unrelated ranking in T2. Because of the lack of correspondence among the tested stability estimates in the two trials, it was difficult to reach a conclusion on producing genotype recommendation based on the univariate statistical approach. However, as GEI has multivariate nature, the multivariate approach is believed to give more robust inference. Hence, some stable genotypes were suggested using the AMMI model for sorghum growing dry lowlands of the country.  相似文献   
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