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991.
The differential localization of the inhibin beta subunits betaA and betaB in the testis of adult bull was studied using specific monoclonal and polyclonal primary antibodies. Inhibin betaA- and betaB-subunits were localized only in the Sertoli cells. The inhibin betaA-subunit was observed in the cytoplasm while the betaB-subunit was localized in the nucleus. No specific findings depending on spermatogenic stages were observed among the seminiferous tubules. Moreover, the inhibin alpha-subunit was not detected in the testis of the bulls. In addition, no inhibin subunits were detected in the Leydig cells and spermatogenic cells. These findings indicate the presence of betaA- and betaB-subunits in the bull, which may suggest a possibility that activin is produced and/or stored in the Sertoli cells and regulates spermatogenesis in an autocrine/paracrine manner. Moreover, the inhibin betaB-subunit may be produced in the nucleus but the functional meaning of this is not yet clear.  相似文献   
992.
993.
A collapse of melon plants (Cucumis melo L.) grown under both winter and summer conditions in Israel was shown to be incited by the soilborne pathogenMacrophomina phaseolina (Tassi) Goid. Although symptoms were noted in the crown area of the plant, results of root isolations confirmed that the damage encountered under local conditions was due primarily to a root rot caused by this pathogen. We found infection to be more prevalent in summer than in winter sowings, and collapse in the summer occurred sooner in later than in earlier sowings. Methyl bromide fumigation controlled the pathogen, prevented collapse, and increased yield as compared with the control treatment.  相似文献   
994.
Abstract

Orobanche is the most debilitating plant parasite of tobacco in Andhra Pradesh. The crop suffers considerably for about six weeks before the parasite appears above the ground. In the absence of effective herbicides for controlling Orobanche especially in this pre-emergence phase, it was felt worthwhile to evaluate the effectiveness of various cultivated crops as trap crops. A preliminary pot trial was conducted with 17 crop plants and the results are presented.  相似文献   
995.
乌龙茶种质资源种群遗传多样性AFLP评价   总被引:18,自引:1,他引:18  
以银染法AFLP分子标记技术用5对引物组合对来自福建武夷山市、安溪县、台湾省和广东潮安县45份乌龙茶品种资源进行遗传多样性分析。结果表明,5对引物扩增出208条多态性条带,多态性为92.03%;最大遗传距离为0.481,最小遗传距离为0.124,种质资源间遗传多样性估值较高,达0.311。按照地理分布分组分析表明,种群内遗传多样性以武夷山最高,其次为安溪乌龙茶种质资源,以台湾的乌龙茶种质资源遗传多样性最小;种群间遗传相似性,以武夷山与安溪种群间最高,达0.9505,以台湾和潮安县类型间的相似性最低,相似性系数为0.77。构建的种间和种群间进化树表明,可将45份乌龙茶品种划分为二大类型,福建类型和广东潮安类型。结合种群间相似系数,提出乌龙茶种质资源与其加工工艺的演化路径是一致的,也是由武夷山向安溪再向台湾传播。  相似文献   
996.
To quantitate acetylpromazine-induced alpha-adrenergic receptor blockade, phenylephrine was infused into dogs. The amount of phenylephrine necessary to increase the mean arterial blood pressure (MAP) 50% above base line, with or without the prior administration of acetylpromazine, served to quantify the degree of acetylpromazine-induced alpha-adrenergic receptor blockade. Seven dogs were anesthetized with thiopental, maintained on halothane in oxygen, and mechanically ventilated. All infusions were made through a catheter in the cephalic vein. Continuous recordings were made of MAP and a lead II ECG. After induction of anesthesia, instrumentation, and stabilization of heart rate, MAP, and ventilation, 6 group I dogs were infused with phenylephrine until a 50% increase in MAP was recorded (phenylephrine control). On subsequent research days, each dog was anesthetized, instrumented as described, and given (IV) 1 of 3 dosages of acetylpromazine in the following order--0.05, 0.125, and 0.25 mg/kg. The dose of phenylephrine necessary to increase MAP 50% in the presence of acetylpromazine was recorded. Five group II dogs were studied as in group I, but each dog was given (IM) atropine (0.04 mg/kg) before anesthetization. Two dosages of acetylpromazine were studied in the following order--0.05 and 0.25 mg/kg. Group I dogs, when compared with their phenylephrine controls, were given significantly more phenylephrine to raise MAP 50% at each dose of acetylpromazine studied. The same trend was observed in group II dogs, but at smaller doses of phenylephrine, probably as a result of the positive chronotropic effect of atropine on the heart.  相似文献   
997.
The dinoflagellate Prorocentrum cordatum, often called P. minimum, is a potentially toxic alga found in algal blooms. Volatile compounds released by the alga might carry important information, e.g., on its physiological state, and may act as chemical messengers. We report here the identification of volatile organic compounds emitted by two strains, xenic P. cordatum CCMP 1529 and axenic P. cordatum CCMP 1329. The volatiles released during culture were identified despite their low production rates, using sensitive methods such as open-system-stripping analysis (OSSA) on Tenax TA desorption tubes, thermodesorption, cryofocusing and GC/MS-analysis. The analyses revealed 16 compounds released from the xenic strain and 52 compounds from the axenic strain. The majority of compounds were apocarotenoids, aromatic compounds and small oxylipins, but new natural products such as 3,7-dimethyl-4-octanolide were also identified and synthesized. The large difference of compound composition between xenic and axenic algae will be discussed.  相似文献   
998.
999.
1000.
Endocarditis caused by Corynebacterium sp in a dog   总被引:1,自引:0,他引:1  
Mitral valve bacterial endocarditis, caused by Corynebacterium sp, was diagnosed in a dog. The bacteria had characteristics unlike those commonly recognized for most species of Corynebacterium. The primary source of bacteremia was suspected to be a pilonidal cyst of the sacrum. The dog was treated with a first-generation cephalosporin for 6 weeks, and the pilonidal cyst was surgically removed. Physical examination 1 year after initial examination revealed no abnormalities other than a cardiac murmur. On echocardiographic examination 1 year after treatment, the vegetative lesion was still present; however, chamber dimensions had returned to normal. Wall thickness and contractility remained increased.  相似文献   
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