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31.
穴位激光照射对兔子宫类固醇激素受体的影响   总被引:1,自引:0,他引:1  
黄平  黄文心 《激光生物学报》1994,3(3):497-502,493
对兔用He-Ne激光照射穴位,照射外生殖器,用类固醇激素受体测定法测定子宫雌二醇受体(ER)和孕酮受体(PR)含量。照射穴位后部分实验组的ER和PR浓度上升,与正常对照组相比较有显著或极显著差别(P<0.05,P<0.01),ER提高1.7-3.2倍,PR提高2.7-3.7倍。实验结果提示激光可通过类固醇激素受体浓度的提高,在受体水平上影响机体代谢。  相似文献   
32.
乐安江沉积物中金属污染的潜在生态风险评价   总被引:114,自引:3,他引:114  
选择污染严重的乐安江河流沉积物为对象,利用风险因子E和风险指数RI等定量诊断工具开展沉积物中重金属污染的潜在生态风险评价。根据风险指标体系和空间分异规律,将流域划分居不同特征的4种生态风险功能区。对比评价效果。潜在生态风险评价与地积累 情况大同小异,可以相互补充和借鉴。  相似文献   
33.
We report the morphology and morphogenesis of Urosoma caudata (Ehrenberg, 1833) Berger, 1999 based on in vivo observation and protargol impregnation and provide an improved diagnosis of Ucaudata based on previous and current work. Urosoma caudata differs from its congeners mainly by the combination of the following features: tail‐like posterior end, colorless cortical granules, and two macronuclear nodules. Urosoma caudata shares most of the ontogenetic features with its congeners: the oral primordium of the opisthe develops apokinetally, and the frontal‐ventral‐transverse cirral anlagen develop in five streaks. However, a unique morphogenetic characteristic is recognizable: the anlagen of three dorsal kineties occur de novo to the left of the parental structures differing from their intrakinetal origin in other Urosoma species. The first record of the 18S rRNA gene sequence for the species is also provided. Phylogenetic analyses based on 18S rRNA gene sequence data suggest that the genus Urosoma is a nonmonophyletic group.  相似文献   
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Many stem cell populations are tightly regulated by their local microenvironment (niche), which comprises distinct types of stromal cells. However, little is known about mechanisms by which niche subgroups coordinately determine the stem cell fate. Here we identify that Yki, the key Hippo pathway component, is essential for escort cell (EC) function in promoting germline differentiation in Drosophila ovary. We found that Hedgehog (Hh) signals emanating primarily from cap cells support the function of ECs, where Cubitus interruptus (Ci), the Hh signaling effector, acts to inhibit Hippo kinase cascade activity. Mechanistically, we found that Ci competitively interacts with Hpo and impairs the Hpo-Wts signaling complex formation, thereby promoting Yki nuclear localization. The actions of Ci ensure effective Yki signaling to antagonize Sd/Tgi/Vg-mediated default repression in ECs. This study uncovers a mechanism explaining how subgroups of niche cells coordinate to determine the stem cell fate via Hh-Hippo signaling crosstalk, and enhances our understanding of mechanistic regulations of the oncogenic Yki/YAP signaling.  相似文献   
37.
Waste is unwanted or useless material. It is widely recognized that waste materials are valuable resources, whilst there is debate as to how this value is best realized. Re-use, recycling and energy recovery are being applied to regulated wastes. Yet, while recycling and re-use are increasing, the overall amounts of waste are still growing, and there is an increasing demand for primary resources and stress on eco-systems. In this webalert, we will focus on some important websites which provide readers with more informative resources related to waste management.  相似文献   
38.
The de novo design of protein-protein interfaces is a stringent test of our understanding of the principles underlying protein-protein interactions and would enable unique approaches to biological and medical challenges. Here we describe a motif-based method to computationally design protein-protein complexes with native-like interface composition and interaction density. Using this method we designed a pair of proteins, Prb and Pdar, that heterodimerize with a Kd of 130 nM, 1000-fold tighter than any previously designed de novo protein-protein complex. Directed evolution identified two point mutations that improve affinity to 180 pM. Crystal structures of an affinity-matured complex reveal binding is entirely through the designed interface residues. Surprisingly, in the in vitro evolved complex one of the partners is rotated 180° relative to the original design model, yet still maintains the central computationally designed hotspot interaction and preserves the character of many peripheral interactions. This work demonstrates that high-affinity protein interfaces can be created by designing complementary interaction surfaces on two noninteracting partners and underscores remaining challenges.  相似文献   
39.
He Q  Ren P  Kong X  Xu W  Tang H  Yin Y  Wang Y 《Molecular bioSystems》2011,7(7):2147-2155
Intrauterine growth restriction (IUGR) is not only an underlying factor for stunted postnatal growth and newborn deaths, but also associated with disease prevalence, such as hypertension and diabetes, in both adult humans and animals. To investigate the metabolic status of IUGR, the differences in serum and jejunal tissue metabonome were examined in IUGR and normal weight 21 day old piglets. IUGR piglets had a significantly lower birth weight (785 ± 42 g vs. 1451 ± 124 g), weaned weight (3053 ± 375 g vs. 6489 ± 545 g) and average daily gain (108 ± 16 g vs. 240 ± 21 g) than normal weight piglets (p < 0.05). IUGR piglets also had a shorter villus height and smaller villus height to crypt depth ratio (p < 0.05) in jejunum. An NMR-based metabonomic study found that serum levels of glycoprotein, albumin and threonine were higher in IUGR than in normal weight piglets, while serum levels of HDL, lipids, unsaturated lipids, glycerophosphorylcholine, myo-inositol, citrate, glutamine and tyrosine were lower in IUGR piglets (p < 0.05). In addition, marked changes in jejunal metabolites, including elevated levels of lipids and unsaturated lipids, and decreased levels of valine, alanine, glutamine, glutamate, choline, glycerophosphorylcholine, trimethylamine-N-oxide, scyllo-inositol, lactate, creatine, glucose, galactose, phenylalanine, tyrosine, glutathione, inosine and taurine were observed in IUGR piglets (p < 0.05). These novel findings indicate that IUGR piglets have a distinctive metabolic status compared to normal weight piglets, including changes in lipogenesis, lipid oxidation, energy supply and utilization, amino acid and protein metabolism, and antioxidant ability; these changes could contribute to impaired growth and jejunal function.  相似文献   
40.
Chai Y  Xu H  Wang W  Liu B  Yang D  Fan H  Song F  Lu Z 《PloS one》2011,6(7):e21718

Background

For decades the development of community health services has been emphasized in China to cope with the growing burden of chronic diseases by providing basic medical services. This survey aims at investigating factors associated with the use of Community Health Centers (CHCs) for the management of hypertensive patients in Chengdu, China.

Methods

We used a systematic sampling method to select 2,030 patients with hypertension or diabetes registered in 29 CHCs in Chengdu in 2007. Researchers interviewed patients who consented to participate at their home. This paper reports findings from the survey of 1,716 hypertensive patients with completed questionnaires. Univariate analyses and multiple logistic regression analyses were conducted to explore factors influencing the use of CHCs for the management of hypertensive patients.

Results

81.4% of hypertensive patients regularly used CHCs for hypertension monitoring and treatment in Chengdu. Univariate analyses indicated that use of CHCs was associated with the education level, occupation, types of medical insurance, Body Mass Index(BMI), patients'' knowledge on hypertension, awareness of CHCs functions, satisfaction of the service of CHCs. Multiple regression analyses found that use of CHCs was positively associated with the following factors: the Urban Resident Basic Medical Insurance(URBMI), knowledge on blood pressure, awareness of the sites in CHCs to measure blood pressure, awareness of having to take life-long antihypertensive medicine once the treatment started, awareness of the health records registration in CHCs, regular follow up, improved convenience of seeing doctor. Patients with professional job were less likely to use the services of CHCs.

Conclusions

The use of CHCs for hypertension management could be increased by improving residents'' knowledge on the monitoring and treatment of hypertension, and the awareness of CHCs functions. The CHCs could play an important role in providing medical care to low-income, unemployed and other disadvantaged patients with hypertension.  相似文献   
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