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131.
During a study of the diversity and phylogeny of rhizobia isolated from root nodules of Oxytropis ochrocephala grown in the northwest of China, four strains were classified in the genus Rhizobium on the basis of their 16S rRNA gene sequences. These strains have identical 16S rRNA gene sequences, which showed a mean similarity of 94.4 % with the most closely related species, Rhizobium oryzae. Analysis of recA and glnA sequences showed that these strains have less than 88.1 and 88.7 % similarity with the defined species of Rhizobium, respectively. The genetic diversity revealed by ERIC-PCR fingerprinting indicated that the isolates correspond to different strains. Strain CCNWQLS01T contains Q-10 as the predominant ubiquinone. The major fatty acids were identified as feature 8 (C18: 1ω7c and/or C18: 1ω6c; 67.2 %). Therefore, a novel species Rhizobium qilianshanense sp. nov. is proposed, and CCNWQLS01T (= ACCC 05747T = JCM 18337T) is designated as the type strain.  相似文献   
132.
Huang LH  Zheng YF  Song CJ  Wang YG  Xie ZY  Lai YW  Lu YZ  Liu HM 《Steroids》2012,77(5):367-374
The preparation of novel steroidal heterocycles containing the 7-aryl-substituted 1,2,4-triazolo[1,5-a]pyrimidine moiety fused to the 16,17-positions of the steroid nucleus is described. The Aldol reaction of 4-aza-androst-3,17-dione (1a) and dehydroepiandrosterone (DHEA, 1b) with aromatic aldehydes was catalyzed by KF/Al(2)O(3) to give the corresponding 3-oxo-4-aza-5α- and 3β-hydroxy-5-en-16-arylidene-17-ketosteroids (2a-r). Subsequently, the intermediates 2a-r reacted with dinucleophilic 3-amino-1,2,4-triazole in presence of t-BuOK to afford the title compounds (3a-r). All the synthesized heterosteroids are new and are currently being evaluated for their biological activities.  相似文献   
133.

Background

Previous association studies examining the relationship between the APOC1 polymorphism and susceptibility to Alzheimer’s disease (AD) have shown conflicting results, and it is not clear if an APOC1 variant acts as a genetic risk factor in AD etiology across multiple populations.

Methods

To confirm the risk association between APOC1 and AD, we designed a case-control study and also performed a meta-analysis of previously published studies.

Results

Seventy-nine patients with AD and one hundred fifty-six unrelated controls were included in case-control study. No association was found between the variation of APOC1 and AD in stage 1 of our study. However, our meta-analysis pooled a total of 2092 AD patients and 2685 controls. The APOC1 rs11568822 polymorphism was associated with increased AD risk in Caucasians, Asians and Caribbean Hispanics, but not in African Americans. APOE ε4 carriers harboring the APOC1 insertion allele, were more prevalent in AD patients than controls (χ2 = 119.46, OR = 2.79, 95% CI = 2.31–3.36, P<0.01).

Conclusions

The APOC1 insertion allele, in combination with APOE ε4, likely serves as a potential risk factor for developing AD.  相似文献   
134.
135.
An experiment was conducted in a 3?×?3?+?1 factorial experiment based on a completely randomized design to evaluate the effects of different sources of copper on growth performance, nutrient digestibility and elemental balance in young female mink on a corn–fishmeal-based diet. Animals in the control group were fed a basal diet (containing 8.05 mg Cu/kg DM; control), which mainly consisted of corn, fish meal, meat bone meal, and soybean oil, with no copper supplementation. Minks in other nine treatments were fed basal diets supplemented with Cu from reagent-grade copper sulfate, tribasic copper chloride (TBCC) and copper methionate. Cu concentrations of experiment diets were 10, 25, and 40 mg/kg copper. A metabolism trial of 4 days was conducted during the last week of experimental feeding. Final body weight and average daily gain increased (linear and quadratic, P?<?0.05) as Cu increased in the diet; maximal growth was seen in the Cu25 group. Cu supplementation slightly improved the feed conversion rate (P?=?0.095). Apparent fat digestibility was increased by copper level (P?=?0.020). Retention nitrogen was increased by copper level (linear, P?=?0.003). Copper source had a significant effect on copper retention with Cu-Met and copper sulfate treatments retention more than TBCC treatments (P?<?0.05). Our results indicate that mink can efficiently utilize added dietary fat and that Cu plays an important role in the digestion of dietary fat in mink, and mink can efficiently utilize Cu-Met and CuSO4.  相似文献   
136.
Previous research demonstrated excessive decreases in reward sensitivity and increases in harm avoidance in depressed individuals. These results straightly lead to a hypothesis that depressed patients should avoid novelty or express reduced novelty-seeking behavior. Nevertheless, literature in this regard is inconsistent. Furthermore, whether the potentially altered novelty-associated behavior is dependent on changed anxiety/fear or related to altered goal-directed approaching tendency is unclear. Here, we tested novel object-approaching behavior in a free-exploration paradigm in chronic mild stress (CMS)-induced anhedonic and stress-resistant rats respectively. Other CMS-induced, emotional behaviors were also examined in a battery of behavioral tests including novel cage, exploration, locomotor activity and elevated plus maze (EPM). We found that compared with controls, stress-resistant rats who consistently showed lower anxiety level in EPM (time in open arms) and, open-field (OF) test (time in central area) showed no sign of enhanced novel object approaching behavior. To the contrary, the anhedonic ones who did not express any sign of reduced anxiety showed paradoxically intensified novelty-approaching behavior. We concluded that reduced anxiety would not necessarily lead to enhanced novelty-seeking behavior; anhedonia coexists with anxiety-independent, increased novelty-seeking behavior. The salient paradox of coexistence of anhedonia and increased novelty-seeking behavior was critically discussed.  相似文献   
137.
Liu  Xi  Ding  Li  Yuan  Jing  Liao  Jian  Duan  Lian  Wang  Wenfei  Tan  Weiguo  Yu  Weiye  Zhou  Boping  Chen  Xinchun  Yang  Zheng 《中国病毒学》2019,34(3):334-337
<正>Dear Editor,H7 N9 is a recently identified subtype of influenza A virus that caused a major outbreak in humans in China in 2013.According to the latest data provided by the Chinese Center for Disease Control and Prevention(http://www.moh.gov.cn/zwgk/yqbb3/ejlist.shtml, updated on October 31, 2018),the mortality rate of H7 N9 infections in China amounts to  相似文献   
138.
139.

Background

The HIV-epidemic among MSM in China has worsened. In this key population, prevalence of HSV-2 and syphilis infection and co-infection with HIV is high.

Methods

A longitudinal study was conducted (n = 962) in Beijing, China, with three overlapping cohorts (n = 857, 757 and 760) consisting of MSM that were free from pairs of infections of concern (i.e. HIV-HSV-2, HIV-syphilis, HSV-2-syphilis) at baseline to estimate incidence of HIV, HSV-2, syphilis, and those of co-infection.

Results

The incidence of HIV, HSV-2 and syphilis in the overall cohort was 3.90 (95% CI = 2.37, 5.43), 7.87 (95% CI = 5.74, 10.00) and 6.06 (95% CI = 4.18, 7.94) cases per 100 person-years (PYs), respectively. The incidence of HIV-HSV-2, HIV-Syphilis and HSV-2-Syphilis co-infections was 0.30 (95% CI = 0.29, 0.88), 1.02 (95% CI = 0.13, 2.17) and 1.41 (95% CI: 0.04, 2.78) cases per 100 PYs, respectively, in the three sub-cohorts constructed for this study.

Conclusions

The incidence of HIV, HSV-2 and syphilis was very high and those of their co-infections were relatively high. Such co-infections have negative impacts on the HIV/STI epidemics. Prevention practices need to take such co-infections into account.  相似文献   
140.
为分析牙周病的发病与人口爱螺旋体的热休克蛋白的关系。通过SDS-PAGE电泳将菌体蛋白分离,转移电泳(Western blot)检查螺旋体的热休克蛋白抗原,牙周病患者血清与螺旋体的热休克蛋白进行免疫印迹试验检查灯克蛋白抗体。结果为实验所用的螺旋体有4种可诱导产生质变休克蛋白,患者血清中有多种对于口腔螺旋体蛋白能起作用的本,其中有两名患者的血清对T.socranskii35535菌株的60kD或65  相似文献   
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