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11.
本文用放射免疫测定法对7只雌性恒河猴(Macaca mulatta)的20个月经周期进行了雌二醇、孕酮和睾酮的动态测定分析,其中15个月经周期的中期都有睾酮和雌二醇峰(其峰值分别为1010.7±411.3pg/ml和179.1±91.3pg/ml),孕酮在黄体期的峰值为2.54±0.65ng/ml。正常黄体期的血清孕酮水平不低于1ng/ml。20个月经周期的平均天数为28.6±5.4天,滤泡期和黄体期分别为11.9±2,6和19.2±6.3天。月经周期可用公式Y=18.92±0.03×X~2 (Y:月经周期,X:黄体期。R=0.9444)表示。实验结果表明,测定周期内三种性类固醇激素可以准确确定排卵。睾酮在生殖周期内的分泌调节机制还待进一步研究。  相似文献   
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油菜与紫云英间混作系统的生理生态效应   总被引:5,自引:0,他引:5  
采用7种耕种方式研究油菜与紫云英间混作系统中油菜生长发育、产量形成及其效益.结果表明,育苗移栽油菜的株高、叶片大小、根颈粗、开盘度以及产量指标均明显优于免耕直播油菜;与紫云英混作的免耕直播油菜,各形态指标均优于免耕直播间作和单作油菜.耕翻后与紫云英混作的育苗移栽油菜产量比免耕直播单作油菜增产11.9%;与紫云英混作的免耕育苗移栽油菜产量与免耕直播单作相近.耕翻后与紫云英混作的育苗移栽油菜产值和效益最大,免耕直播油菜单作其次.结合产投比和土地当量比,耕翻后与紫云英混作育苗移栽油菜和与紫云英混作免耕育苗移栽油菜两种方式综合效益最高,增产增收,增加有机肥源,提高土壤肥力.  相似文献   
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Hu K 《FEBS letters》2006,580(27):6361-6365
Mechanisms for loss and gain of introns are elusive. Reported here is a new pattern of intron loss which features a random loss of a single intron in a multiple-intron gene with its neighboring introns remained, which process is defined as intron exclusion. Intron exclusion is reminiscent of removal of a limited stretch of non-homologous sequence in a homologous recombination (HR) triggered by a double strand break (DSB), and therefore lends further evidence for a theory of intron loss through HR between a cDNA and its genomic intron-containing locus. Thus, a model for intron loss is formulated.  相似文献   
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The relationship between ethylene and cyanide (HCN) and karrikin 1 (KAR1) in dormancy release was studied in secondary dormant Brassica oleracea L. (Chinese cabbage) seeds. Freshly harvested seeds of Brassica oleracea usually have poor germination potential. Karrikin1 (KAR1) and cyanide (HCN) are able to stimulate seed germination. However, the stimulatory effects of these two chemicals depend on the activation of the ethylene biosynthesis pathway and on ethylene perception. In this study, KAR1 and HCN application increased the activity of ethylene and of two ethylene biosynthesis enzymes, ACC synthase (ACS) and ACC oxidase (ACO). KAR1 and HCN collectively promoted the accumulation of 1 aminocyclopropane-1-carboxylic acid (ACC). In the presence of NO (nitric oxide) and KAR1, ACS and ACO activities reached their maximum levels after 36 and 42 h, respectively. Ethylene inhibitors suppressed seed germination by approximately 55%, whereas the respiratory inhibitors SHAM and NaN3 inhibited seed germination by 5–10% in the presence of HCN and KAR1. KAR1 and HCN collectively reduced the abscisic acid (ABA) content in seeds, increased the gibberellic acid (GA) content and released seed dormancy. The expression of ethylene biosynthesis genes and ethylene receptor genes (BOACO1, BOACS1, BOACS3, BOACS4, BOACS5, BOACS7, BOACS9, BOACS11, BOETR1 and BOETR2) provided further evidence of the involvement of ethylene in KAR1 and HCN-induced germination. BOACO1, BOACS1, BOACS5, BOACS7, BOACS9, BOACS11, BOETR1 and BOETR2 genes were up regulated in the presence of KAR1 and HCN, while the remaining genes were down regulated. The expression of various ethylene biosynthesis and ethylene receptor genes suggested functional diversification and variations in seed sensitivity in the presence of KAR1 and HCN. Therefore, in the current study, KAR1 and HCN application effectively induced the germination of B. oleracea seeds (approximately 97% germination rate) after 6 days by modifying the ethylene biosynthetic pathway.

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Background

Periodontal disease is common among adults and is associated with an increasing risk of chronic kidney disease (CKD). We aimed to investigate the prevalence and risk factors of CKD in patients with periodontal disease in China.

Methods

In the current cross-sectional study, patients with periodontal disease were included from Guangdong Provincial Stomatological Hospital between March 2011 and August 2011. CKD was defined as estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2, the presence of albuminuria, or hematuria. All patients with periodontal disease underwent a periodontal examination, including periodontal probing pocket depth, gingival recession, and clinical attachment level by Florida Probe. They completed a questionnaire and had blood and urine samples taken. The adjusted prevalence of indicators of kidney damage was calculated and risk factors associated with CKD were analyzed.

Results

A total of 1392 patients with periodontal disease were invited to participate this study and 1268 completed the survey and examination. After adjusting for age and sex, the prevalence of reduced eGFR, albuminuria, and hematuria was 2.7% (95% CI 1.7–3.7), 6.7% (95% CI 5.5–8.1) and 10.9% (95% CI 9.2–12.5), respectively. The adjusted prevalence of CKD was 18.2% (95% CI 16.2–20.3). Age, male, diabetes, hypertension, history of CKD, hyperuricemia, and interleukin-6 levels (≥7.54 ng/L) were independent risk factors for reduced eGFR. Female, diabetes, hypertension, history of CKD, hyperuricemia, high level of cholesterol, and high sensitivity C-reactive protein (hsCRP) (≥1.03 mg/L) and TNF-α levels (≥1.12 ng/L) were independently associated with an increased risk of albuminuria. Female, lower education (<high school), and history of CKD were independent risk factors for hematuria.

Conclusions

18.2% of Chinese patients with periodontal disease have proteinuria, hematuria, or reduced eGFR, indicating the presence of kidney damage. Whether prevention or treatment of periodontal disease can reduce the high prevalence of CKD, however, remains to be further investigated.  相似文献   
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The mammalian liver has a very strong regeneration capacity after partial hepa- tectomy (PH). To further learn the genes participating in the liver regeneration (LR), 551 cDNAs selected from subtracted cDNA libraries of the regenerating rat liver were screened by microarray, and their expression pro?les were studied by cluster and generalization analyses. Among them, 177 genes were identi?ed unre- ported and up- or down-regulated more than twofold at one or more time points after PH, of wh…  相似文献   
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