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1.
We have isolated the delta-globin gene of the New-World spider monkey,
Ateles geoffroyi, and compared its nucleotide sequence with those of other
primate delta- and beta-globin genes. Among primate delta-globin genes, the
rate of nonsynonymous substitutions is much less than the rate of
synonymous substitutions. This suggests that primate delta- globin genes
may remain under evolutionary conservation, perhaps because hemoglobin A2
has an as yet unknown physiological importance.
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Giselle?L?Ferrari Jefferson?LB?Marques Rajiv?A?Gandhi Simon?R?Heller Fábio?K?Schneider Solomon?Tesfaye Humberto?R?GambaEmail author 《Biomedical engineering online》2010,9(1):26
Background
Autonomic neuropathy is a common and serious complication of diabetes. Early detection is essential to enable appropriate interventional therapy and management. Dynamic pupillometry has been proposed as a simpler and more sensitive tool to detect subclinical autonomic dysfunction. The aim of this study was to investigate pupil responsiveness in diabetic subjects with and without cardiovascular autonomic neuropathy (CAN) using dynamic pupillometry in two sets of experiments. 相似文献5.
Spiroplasma species in the Costa Rican highlands: implications for biogeography and biodiversity 总被引:1,自引:0,他引:1
Robert F. Whitcomb Joseph G. Tully Gail E. Gasparich Laura B. Regassa David L. Williamson Frank E. French 《Biodiversity and Conservation》2007,16(13):3877-3894
More than 1,000 Spiroplasma isolates have been obtained from horse flies and deer flies (Diptera:Tabanidae) in the United States and Canada. However, the spiroplasma biota of Central America is poorly known. In August of 1995 and
1998, 13 isolates were obtained in 14 attempts from horse flies of a single species, Poeciloderas quadripunctatus, taken in the Costa Rican highlands (1,100–2,000 m). The majority of the “isolates” proved to be mixtures of two or more
Spiroplasma species, but after filter cloning, single strains emerged that were designated as representatives of the 13 accessions. Six
distinct spiroplasma serogroups were identified from these isolations. Three of the strains are putative new species with
no serological relationship to any other Spiroplasma species. A fourth strain is a putative new species that may be distantly related to S. helicoides, a southeastern U.S. species. These four strains are accorded herein status as representatives of new serogroups: strain
BARC 4886 (group XXXV); strain BARC 4900 (group XXXVI); strain BARC 4908 (group XXXVII); and GSU5450 (group XXXVIII). A fifth
Spiroplasma species was very closely related to S. lineolae, known previously only from the Georgia (U.S.) coast. The sixth was most closely related to subgroup VIII-3, known from Texas
and the southeastern U.S. Discovery of six spiroplasma species in only 13 attempted isolations reflects diversity seldom equaled
in southeast Georgia, and never elsewhere in the U.S. These results are consistent with a hypothesis that spiroplasma diversity
increases from north (Nova Scotia) to south (Georgia and Costa Rica). The discovery of significant affinity between some spiroplasmas
of the southeastern U.S. and the Costa Rican highlands was unexpected, but may reflect a climatically complex Pleistocene
history.
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Robert F. WhitcombEmail: |
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This study examined the nutritional status of mothers in one of the most populous food-insecure zones in southern Ethiopia, the Sidama zone. The study used primary data collected from 1094 households with a child under 24 months located in ten kebeles (the smallest administrative district). Households were selected using multi-stage probability sampling techniques. The mothers' nutritional status was estimated using both body mass index (BMI) and mid-upper-arm circumference (MUAC). The results from the BMI analysis revealed that 28.1% of the women were malnourished (BMI <18.5) and 67.5% were normal (BMI 18.5 to <25.0), while the remaining small proportion (4.5%) fell in the overweight or obese categories. Similarly, the computation of maternal nutritional status by MUAC analysis showed that 31.4% of the women were malnourished (MUAC <22). Further analysis of the main predictors of maternal malnutrition using logistic regression showed that three individual-level variables and three household-level variables predicted maternal malnutrition: woman's age, duration of breast-feeding, literacy status, marital form, land size and intra-household food distribution. The study concludes that maternal malnutrition is a serious problem in the study area and that there are contextual risk factors that could be addressed to partially tackle the problem. 相似文献
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一种新的肝细胞生成素(HPO)转录本及其生物学活性 总被引:3,自引:1,他引:2
利用 5′RACE技术从人胎肝组织中分离一种新形式的肝细胞生成素 (HPO 2 0 5 )cDNA ,其编码蛋白质氨基酸序列的N端较已报道的人肝细胞生成素HPO(hepatopoietin)多 80个氨基酸 ,推测其蛋白质分子量为 2 3kD。RT PCR检测HPOmRNA在多种肝癌细胞中表达 ,Western印迹可检测到 2 3kDHPO 2 0 5表达 ,表明此种形式HPO在自然状态下存在。将构建的HPO 2 0 5真核表达载体转染入COS 7细胞 ,其表达蛋白质能够刺激HepG2肝癌细胞DNA合成 ;将HPO 2 0 5、HPO和荷空表达载体分别转染入低水平表达HPO的Bel 740 2肝癌细胞株 ,发现HPO 2 0 5比HPO具有较强的激活MAPK磷酸化的活性。细胞周期分析稳定转染HPO 2 0 5 ,HPO细胞的增殖周期也支持这一结论。这些结果表明HPO 2 0 5具有刺激肝源性细胞增殖的活性 ,并提示HPO 2 0 5可能较HPO有更强的生物学活性 相似文献
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棕色固氮菌(Azotobacter vinelandii Lipmann)突变种UW3能在无Mo的无氨培养基中固氮生长,低浓度的Mn对UW3突变种生长有促进作用,从在Mn中生长的UW3菌体中分离得到的部分纯固氮酶组分Ⅰ蛋白含量有Mn和Fe原子(Fe/Mo/Mn为10.41:0.19:1.00)并有OP MoFe蛋白一半的还原乙炔和质子的活性。这种蛋白的吸收光谱和圆二色谱与MoFe蛋白存在明显的差异,含Mn蛋白的亚基分子量都与MoFe蛋白的α亚基相近。初步结果表明,这种含Mn蛋白可胡是一种固氮酶组分Ⅰ蛋白。 相似文献
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在合适的结晶条件下 ,从含Cr无氨培养基中生长的固氮菌 (AzotobactervinelandiiLipmann)突变种UW3 中纯化出的CrFe蛋白可从溶液中析出深棕色斜四棱柱晶体 ,晶体最大的两条对角线长度分别可达 0 .2 5mm和 0 .12mm。PEG 80 0 0、MgCl2 、NaCl、Tris和Hepes缓冲液的浓度及结晶方法等对该蛋白的出晶率、晶核数目、晶体大小和质量都有明显影响。CrFe蛋白结晶所需的上述化合物的最适浓度与在Mn中生长的固氮菌突变种UW3 的MnFe蛋白和缺失nifZ固氮菌突变种的ΔnifZMoFe蛋白结晶所需的最适浓度有所不同。结果表明 ,该蛋白晶体可能为CrFe蛋白的晶体 相似文献
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Abattoir evidence on association between uterine and ovarian abnormalities in Ethiopian highland ewes 总被引:1,自引:0,他引:1
A study was conducted on 3275 non-pregnant Ethiopian highland ewes slaughtered at the Addis Ababa municipal abattoir to determine whether uterine and ovarian abnormalities were associated. Each reproductive tract was examined for the presence of ovarian cysts, ovarobursal adhesions and gross uterine abnormalities. The percentage of ewes with ovarian cysts, ovarobursal adhesions and combination of both on the same ovary was 4.3%, 7.6% and 1.7%, respectively. The percentage of uterine abnormalities in tracts with ovarian cysts, ovarobursal adhesions, combined ovarian cysts and ovarobursal adhesions and those with normal ovaries was 46.1%, 31.9%, 46.3% and 4.3%, respectively. The prevalence of uterine abnormalities including hydro/mucometra, endometritis and pyometra was significantly higher (P<0.001) in ewes with abnormal ovarian conditions than in those with normal ovaries. Also, the prevalence of uterine abnormalities was higher (P<0.01) in ewes with ovarian cysts than in those with ovarobursal adhesions alone while in those ewes with co-existing ovarian cysts and ovarobursal adhesions it did not differ (P>0.05) from those with either of these ovarian conditions. Among uterine abnormalities hydro/mucometra was higher (P<0.01) in ewes with abnormal ovaries. In both groups of ewes with and without ovarian abnormalities pyometra was the least prevalent uterine disorder. These results indicate a direct strong association between uterine and ovarian abnormalities in the Ethiopian highland ewes. 相似文献