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971.
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973.
In insect eggs, the chorion has the essential function of protecting the embryo from external agents during development while allowing gas exchange for respiration. In this study, we found a novel gene, Nilaparvata lugens chorion protein (NlChP), that is involved in chorion formation in the brown planthopper, Nilaparvata lugens. NlChP was highly expressed in the follicular cells of female adult brown planthoppers. Knockdown of NlChP resulted in oocyte malformation and the inability to perform oviposition, and electron microscopy showed that the malformed oocytes had thin and rough endochorion layers compared to the control group. Liquid chromatography with tandem mass spectrometry analysis of the eggshell components revealed four unique peptides that were matched to NlChP. Our results demonstrate that NlChP is a novel chorion protein essential for egg maturation in N. lugens, a hemipteran insect with telotrophic meroistic ovaries. NlChP may be a potential target in RNA interference‐based insect pest management.  相似文献   
974.
目的:探讨青光眼术后白内障在小瞳孔下超声乳化联合人工晶状体植入术的临床疗效及手术技巧。
  方法:采用超声乳化白内障摘出联合人工晶状体植入术治疗小瞳孔青光眼术后白内障36例36眼,均采用透明角膜切口植入折叠人工晶状体,观察比较手术前后视力、眼压滤过泡及并发症情况,术后随访3 mo。
  结果:术前裸眼视力或最佳矫正视力均≤0.3,术后1wk最佳矫正视力≥0.3者23眼(63.89%),术后3mo随访视力≥0.3者34眼(94.44%),视力<0.3者2眼(5.56%),其中1眼为青光眼术后视神经萎缩,1眼合并糖尿病视网膜病变;眼压控制正常,滤过泡完整,未见严重并发症。
  结论:青光眼术后白内障在小瞳孔下行白内障超声乳化联合人工晶状体植入术手术复杂,手术技巧合理应用仍能取得较好临床效果,影响视力的主要因素是原先存在的视网膜视神经病变。  相似文献   
975.
Limited evidence exists for the association between diet pattern and obesity phenotypes among Chinese adults. In the present study, we analyzed the cross-sectional data from 474,192 adults aged 30–79 years from the China Kadoorie Biobank baseline survey. Food consumption was collected by an interviewer-administered questionnaire. Three dietary patterns were extracted by factor analysis combined with cluster analysis. After being adjusted for potential confounders, individuals following a traditional southern dietary pattern had the lowest body mass index (BMI) and waist circumference (WC); the Western/new affluence dietary pattern had the highest BMI; and the traditional northern dietary pattern had the highest WC. Compared to the traditional southern dietary pattern in multivariable adjusted logistic models, individuals following a Western/new affluence dietary pattern had a significantly increased risk of general obesity (prevalence ratio (PR): 1.06, 95% confidence interval (CI): 1.03–1.08) and central obesity (PR: 1.07, 95% CI: 1.06–1.08). The corresponding risks for the traditional northern dietary pattern were 1.05 (1.02–1.09) and 1.17 (1.25–1.18), respectively. In addition, the associations were modified by lifestyle behaviors, and the combined effects with alcohol drinking, tobacco smoking, and physical activity were analyzed. Further prospective studies are needed to elucidate the diet-obesity relationships.  相似文献   
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979.
Aditoprim (ADP), a new developed dihydrofolate reductase (DHFR) inhibitor, has great potential in clinical veterinary medicine because of its greater pharmacokinetic properties than structural analogs. Preclinical toxicology studies were performed to assess the safety of ADP including an acute oral toxicity test, a subchronic toxicity test and five mutagenicity tests. In the acute oral toxicity test, ADP was administered singly by oral gavage to Wistar rats and Kunming mice. The LD50 calculated was 1400 mg kg–1 body weight (BW) day–1 in rats and 1130 mg kg–1 BW day–1 in mice. In a subchronic study, Wistar rats were administered ADP at dose levels of 0, 20, 100 and 1000 mg kg–1 diet for 90 days. Significant decreases were observed on body weight and food efficiency in the high‐dose group. Treatment‐related changes in clinical serum biochemistry were found in the medium‐ and high‐dose groups. Significant increases in the relative weights of livers and kidneys in females and testis in males in the 1000 mg kg–1 diet, and significant decrease in relative weights of livers in males in the 100 mg kg–1 diet were noted. Histopathological observations revealed that the 1000 mg kg–1 ADP diet could induce lymphocytic infiltration and hepatocytic necrosis near the hepatic portal area. The genotoxicity of ADP was negative in tests, such as the bacterial reverse mutation assay, mice bone marrow erythrocyte micronucleus assay, in vitro chromosomal aberration test, in vitro cho/hgprt mammalian cell mutagenesis assay and mice testicle cells chromosome aberration. Based on the subchronic study, the no‐observed‐adverse‐effect level for ADP was a 20 mg kg–1 diet, which is about 1.44‐1.53 mg kg–1 BW day–1 in rats. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
980.
This paper considers the effect of mental health insurance mandates on the supply of cadaveric donors. We find that enacting a mental health mandate decreases the count of organ donors from suicides and results are driven by female donors. Using a number of empirical specifications, we calculate that the mental health parity laws are responsible for an approximately 0.52% decrease in cadaveric donors. Additional regression results show that the mandates are not related to other types of organ donations, ruling out the possibility that the mandates are related to an overall trend in the supply of organ donations. The findings suggest that future policies aimed at reducing suicide in a large and significant way can potentially increase the inefficiency that currently exists in the organ donor market. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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