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141.
The use of a hair hormone concentration assay is increasingly recognized as a useful and noninvasive technique for monitoring the endocrinological status of animals. However, few studies have focused on reproductive and stress hormones together. We used a chemiluminescent immunoassay to determine whether the progesterone, estradiol, and cortisol concentrations could be measured from hair and whether these hormone concentrations varied in different hair segments of captive Père David deer hinds. We found that progesterone, estradiol, and cortisol could be measured in the hair samples and that the progesterone concentration varied but the estradiol and cortisol concentrations did not among different hair segments. Contrary to the segmental decline in hair cortisol found in many studies, we found that progesterone concentration was higher near the tip than at the base of hair in Père David deer. This suggests that the variation in segmental hair steroid hormone concentration in seasonal molting animals may be mainly due to internal reproductive cycles and that hair steroid hormones may reflect long-term physiological changes and can thus be used for the conservation and management of wildlife.  相似文献   
142.
稻水象甲卵的空间分布型及抽样技术研究   总被引:2,自引:0,他引:2  
本文利用Taylor幂法则和Iwao回归法对稻水象甲LissorhoptrusoryzophilusKuschel卵的空间分布型进行了测定 ,结果表明稻水象甲卵在田间呈聚集分布 ,且符合负二项分布 ,k值为 0 4 796。其种群聚集主要是由环境因子引起的。应用Iwao的抽样模型建立了稻水象甲卵的田间理论抽样数公式 :N =1D2 1 784 6M + 0 2 4 2 5 。并根据Gerrard的零频率模型建立了估计该种群平均密度的零频率模型 :X =1 5 787( -lnP0 ) 1 0 62 5。  相似文献   
143.
Proper priming techniques are among the most important methods for increasing seed germination and seedling growth. Three experiments were conducted to investigate the effects of plant hormone (500 and 1000 mg/L gibberellic acid (GA)), magnetic field (3, 15, 30 mili Tesla (mT)) and laser irradiation at 650 nm (200 mW) on the germination and the growth of Salvia officinalis. We examined the plumule and radical length, plumule and radical fresh weight, plumule and radical dry weight, germination percentage, germination rate and seed vigor. The two concentrations of GA significantly increased seed germination and seedling growth. The magnetic field at 15 mT significantly increased radical length. The effect of laser irradiation was also significant on plumule length, and fresh and dry weight, radicle fresh weight, germination percentage and rate and seed vigor. Such results may be of practical use in the field, especially in arid and semiarid areas, but more research must determine the response of medicinal sage, treated with the priming techniques tested in our experiments, under stress conditions.  相似文献   
144.
Stroke is a leading cause of death, disability, and socioeconomic loss worldwide. The majority of all strokes result from an interruption in blood flow (ischemia) 1. Middle cerebral artery (MCA) delivers a great majority of blood to the lateral surface of the cortex 2, is the most common site of human stroke 3, and ischemia within its territory can result in extensive dysfunction or death 1,4,5. Survivors of ischemic stroke often suffer loss or disruption of motor capabilities, sensory deficits, and infarct. In an effort to capture these key characteristics of stroke, and thereby develop effective treatment, a great deal of emphasis is placed upon animal models of ischemia in MCA.Here we present a method of permanently occluding a cortical surface blood vessel. We will present this method using an example of a relevant vessel occlusion that models the most common type, location, and outcome of human stroke, permanent middle cerebral artery occlusion (pMCAO). In this model, we surgically expose MCA in the adult rat and subsequently occlude via double ligature and transection of the vessel. This pMCAO blocks the proximal cortical branch of MCA, causing ischemia in all of MCA cortical territory, a large portion of the cortex. This method of occlusion can also be used to occlude more distal portions of cortical vessels in order to achieve more focal ischemia targeting a smaller region of cortex. The primary disadvantages of pMCAO are that the surgical procedure is somewhat invasive as a small craniotomy is required to access MCA, though this results in minimal tissue damage. The primary advantages of this model, however, are: the site of occlusion is well defined, the degree of blood flow reduction is consistent, functional and neurological impairment occurs rapidly, infarct size is consistent, and the high rate of survival allows for long-term chronic assessment.  相似文献   
145.
Orthotopic rat liver transplantation is a popular model, which has been shown in a recent JoVE paper with the use of the "quick-linker" device. This technique allows for easier venous cuff-anatomoses after a reasonable learning curve. The device is composed of two handles, which are carved out from scalpel blades, one approximator, which is obtained by modifying Kocher''s forceps, and cuffs designed from fine-bore polyethylene tubing. The whole process can be performed at a low-cost using common laboratory material. The present report provides a step-by-step protocol for the design of the required pieces and includes stencils.  相似文献   
146.
Platelets are the fundamental players in primary hemostasis, but are also involved in several pathological conditions. The remarkable advances in proteomic methodologies have allowed a better understanding of the basic physiological pathways underlying platelet biology. In addition, recent platelet proteomics focused on disease conditions, helping to elucidate the molecular mechanisms of complex and/or unknown human disorders and to find novel biomarkers for early diagnosis and drug targets. The most common and innovative proteomic techniques, both gel-based and gel-free, used in platelet proteomics will be reviewed here. A particular focus will be given to studies that used a subproteomic strategy to analyze specific platelet conditions (resting or activated), compartments (membrane, granules and microparticles) or fractions (phosphoproteome or glycoproteome). The thousands of platelet proteins and interactions discovered so far by these different powerful proteomic approaches represent a precious source of information for both basic science and clinical applications in the field of platelet biology.  相似文献   
147.
Advances in salivary bioscience enable the widespread integration of biological measures into the behavioral and social sciences. While theoretical integration has progressed, much less attention has focused on analytical strategies and tactics. The statistical literature warns that common methods for comparing groups and studying associations can have relatively poor power compared to more modern robust techniques. Here we illustrate, in secondary data analyses using the USC Well Elderly II study (n = 460, age 60–95, 66% female), that modern robust methods make a substantial difference when analyzing relations between salivary analyte and behavioral data. Analyses that deal with the diurnal pattern of cortisol and the association of the cortisol awakening response with depressive symptoms and physical well-being are reported. Non-significant results become significant when using improved methods for dealing with skewed distributions and outliers. Analytical strategies and tactics that employ modern robust methods have the potential to reduce the probability of both Type I and Type II errors in studies that compare salivary analytes between groups, across time, or examine associations with salivary analyte levels.  相似文献   
148.
Pneumonia, the inflammatory state of lung tissue primarily due to microbial infection, claimed 52,306 lives in the United States in 20071 and resulted in the hospitalization of 1.1 million patients2. With an average length of in-patient hospital stay of five days2, pneumonia and influenza comprise significant financial burden costing the United States $40.2 billion in 20053. Under the current Infectious Disease Society of America/American Thoracic Society guidelines, standard-of-care recommendations include the rapid administration of an appropriate antibiotic regiment, fluid replacement, and ventilation (if necessary). Non-standard therapies include the use of corticosteroids and statins; however, these therapies lack conclusive supporting evidence4. (Figure 1)Osteopathic Manipulative Treatment (OMT) is a cost-effective adjunctive treatment of pneumonia that has been shown to reduce patients’ length of hospital stay, duration of intravenous antibiotics, and incidence of respiratory failure or death when compared to subjects who received conventional care alone5. The use of manual manipulation techniques for pneumonia was first recorded as early as the Spanish influenza pandemic of 1918, when patients treated with standard medical care had an estimated mortality rate of 33%, compared to a 10% mortality rate in patients treated by osteopathic physicians6. When applied to the management of pneumonia, manual manipulation techniques bolster lymphatic flow, respiratory function, and immunological defense by targeting anatomical structures involved in the these systems7,8, 9, 10.The objective of this review video-article is three-fold: a) summarize the findings of randomized controlled studies on the efficacy of OMT in adult patients with diagnosed pneumonia, b) demonstrate established protocols utilized by osteopathic physicians treating pneumonia, c) elucidate the physiological mechanisms behind manual manipulation of the respiratory and lymphatic systems. Specifically, we will discuss and demonstrate four routine techniques that address autonomics, lymph drainage, and rib cage mobility: 1) Rib Raising, 2) Thoracic Pump, 3) Doming of the Thoracic Diaphragm, and 4) Muscle Energy for Rib 1.5,11  相似文献   
149.
微卫星的构成及其检测技术   总被引:11,自引:0,他引:11  
微卫星标记是近几年来发展起来的一种新型分子标记,由于其具有检测方便,多态性高、共显性遗传、符合孟德尔遗传定律、重复性好等优点,所以在动物遗传育种中作为标记辅助选择的手段日益得到广泛关注。试就微卫星的构成及特点、以及检测技术及应用作一综述,旨在为该技术的推广应用提供理论依据。  相似文献   
150.
Tu DN  Zou AR  Liao YH  Du YM  Wang XP  Li L 《生理学报》2008,60(4):525-534
采用双电极电压钳技术,研究酮色林对表达在非洲爪蟾卵母细胞上的野生型和Y652突变型人类ether-a-go-go相关基因(human ether-a-go-go-related gene,HERG)钾通道的阻断效应,观测HERG通道的分子位点特性改变对其阻断效应的影响.结果显示,酮色林以电压依赖性和浓度依赖性的方式阻断野生型的HERG钾通道电流.尾电流包裹程序记录电流显示酮色林对HERG钾通道微小的张力性阻断.阻断特征符合对开放状态通道的阻断特征.酮色林也能调节失活状态的HERG钾通道.位于孔道S6区的氨基酸位点突变Y652A和Y652R可显著减弱酮色林对HERG通道的阻断作用.同野生犁HERG钾通道的阻断相比,Y652A突变使阻断的IC50提高72倍,而Y652R突变使阻断的IC50提高53倍.Y652A和Y652R的阴断效应之间没有明显的差别.以上结果提示,酮色林优先阻断开放状态的HERG钾通道,而Y652是酮色林与通道结合的关键位点之一.  相似文献   
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