首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   36篇
  免费   5篇
林业   1篇
农学   1篇
  1篇
水产渔业   5篇
畜牧兽医   32篇
植物保护   1篇
  2022年   1篇
  2021年   1篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2016年   1篇
  2015年   3篇
  2014年   4篇
  2013年   4篇
  2012年   7篇
  2011年   2篇
  2010年   1篇
  2008年   2篇
  2006年   1篇
  2004年   1篇
  2001年   3篇
  2000年   3篇
  1999年   3篇
排序方式: 共有41条查询结果,搜索用时 15 毫秒
21.
To validate the mechanism of cellulose breakdown in cold climate wetlands, we investigated cellulase activity in sediments collected from 17 wetland sites in Hokkaido, the northern area of Japan. We evaluated cellulase activity by quantitative analysis of glucose released from carboxymethyl cellulose and found that sediments from peat fens demonstrated high activity, followed by sediments from lagoons and estuaries. Sediments from peat fens also contained greater amounts of organic matter, followed by lagoons and estuaries, thereby suggesting a strong positive correlation between organic matter content and cellulase activity. Evaluation of cellulase activity by qualitative cellulose zymographic analysis showed that various cellulases with different molecular sizes were implicated in cellulose breakdown in wetlands. Among them, cellulose breakdown in Meguma Pond (peat fen), Notsuke Gulf (peat fen), and Lake Utonai (lagoon) was potentially due to microorganism cellulase, while that in Lake Chobushi (lagoon) was ascribed to meiobenthos (Oligochaeta species) cellulase. The findings presented herein suggest that the origin and activity level of cellulase vary depending on the type of cold climate wetland.  相似文献   
22.
A one-month male Greyhound dog presented with a swinging gait of the hindlimbs, and later developed muscular atrophy of the femoral region and hyperextension of hindlimbs. The dog had positive serum IFAT titers to Neospora caninum, but a negative titer in the cerebrospinal fluid (CSF). N. caninum-specific DNA was amplified from the CSF using a semi-nested polymerase chain reaction assay. Clusters of protozoa in biopsied muscle fibers were subsequently confirmed as N. caninum tachyzoites by immunohistochemical examination. Early recognition and treatment are necessary for effective recovery of clinical canine neosporosis, but antemortem diagnosis is difficult. We suggest that the detection of parasite deoxyribonucleic acid in the CSF is a useful antemortem diagnostic method in facilitating treatment of this disease.  相似文献   
23.
A total of 57 Taylorella equigenitalis (n=22) and Taylorella asinigenitalis (n=35) isolates was shown not to carry any intervening sequences (IVSs) within 16S rRNA gene sequences. By contrast, we have already shown the genus Taylorella group to carry several kinds of IVSs within the 23S rRNA gene sequences.  相似文献   
24.
OBJECTIVE: To characterize respiratory reflexes elicited by nasal administration of sevoflurane (Sevo), isoflurane (Iso), or halothane (Hal) in anesthetized dogs. ANIMALS: 8 healthy Beagles. PROCEDURE: A permanent tracheostomy was created in each dog. Two to 3 weeks later, dogs were anesthetized by IV administration of thiopental and alpha-chloralose. Nasal passages were isolated such that inhalant anesthetics could be administered to the nasal passages while the dogs were breathing 100% O2 via the tracheostomy. Respiratory reflexes in response to administration of each anesthetic at 1.2 and 2.4 times the minimum alveolar concentration (MAC) and the full vaporizer setting (5%) were recorded. Reflexes in response to administration of 5% of each anesthetic also were recorded following administration of lidocaine to the nasal passages. RESULTS: Nasal administration of Sevo, Iso, and Hal induced an immediate ventilatory response characterized by a dose-dependent increase in expiratory time and a resulting decrease in expired volume per unit of time. All anesthetics had a significant effect, but for Sevo, the changes were smaller in magnitude. Responses to administration of each anesthetic were attenuated by administration of lidocaine to the nasal passages. CONCLUSIONS AND CLINICAL RELEVANCE: Nasal administration of Sevo at concentrations generally used for mask induction of anesthesia induced milder reflex inhibition of breathing, presumably via afferent neurons in the nasal passages, than that of Iso or Hal. Respiratory reflexes attributable to stimulation of the nasal passages may contribute to speed of onset and could promote a smoother induction with Sevo, compared with Iso or Hal.  相似文献   
25.
Four wethers were used in a 4 × 4 Latin square design experiment to evaluate the availability of two types of winery wastes, winery sediment and grape pomace, as ruminant feeds possessing antioxidant activities. Each wether was assigned to one of the following four treatments: (i) 75 g/kg winery sediment (WS) on a dry matter (DM) basis; (ii) 166 g/kg DM winery grape pomace (WP); (iii) control diet (CD; 17 g/kg DM soybean meal);and (iv) only tall fescue hay (TFH; no additive). Winery sediment and grape pomace had high levels of polyphenols and of radical scavenging activities. Feeding with winery sediment and grape pomace did not negatively affect the intake, but it depressed crude protein (CP) digestibility compared with CD (P = 0.052 and P < 0.01 for WS and WP, respectively). Polyphenols in winery wastes decreased ruminal ammonia production (P = 0.089 and P < 0.05), likely due to their inhibitive effect on microbial activities in the rumen. The addition of winery sediment and grape pomace decreased urinary 8‐hydroxy‐2'‐deoxyguanosine (8‐OHdG; an index of oxidative damages) excretion per day (P < 0.05 and P = 0.059). The results indicated that winery sediment and grape pomace could alter nitrogen metabolism and/or act as new antioxidants for ruminants.  相似文献   
26.
Thoroughbred horses are seasonal mating animals, raised in northern regions or countries. Foals born yearly in spring generally show a typical seasonal compensatory growth pattern, in which their growth rate declines in the first winter and increases in the next spring. In this study, a new empirical adjustment approach is proposed to adjust for this compensatory growth when growth curve equations are estimated, by using 1,633 male body weights of Thoroughbreds as an illustrating example. Based on general Richards growth curve equation, a new growth curve equation was developed and fit to the weight-age data. The new growth curve equation had a sigmoid sub-function that can adjust the compensatory growth, combined with the Richards biological parameter responsible for the maturity of animals. The unknown parameters included in the equations were estimated by SAS NLMIXED procedure. The goodness of fit was examined by using Akaike’s Information Criterion (AIC). The AIC values decreased from 13,053 (general Richards equation) to 12,794 (the newly developed equation), indicating the better fit of the new equation to the weight-age data. The shape of the growth curve was improved during the period of compensatory growth. The proposed method is one of the useful approaches for adjusting seasonal compensatory growth in growth curve estimations for Thoroughbreds, and for their management during the compensatory period. Based on this approach, the optimal growth curve equations can be estimated also for female body weight of Thoroughbreds or other growth traits affected by seasonal compensatory growth.  相似文献   
27.
28.
The reaction rates ( k s) of tocopherol metabolites (alpha-, gamma-, and delta-CEHC) and Trolox with aroxyl radical have been measured in ethanol and micellar solution by a stopped-flow spectrophotometer, and the k s values obtained were compared with those reported for tocopherols (alpha-, beta-, gamma-, and delta-tocopherol, TocH) and tocol. The rate constants ( k s) increased in the order of Tocol < delta-CEHC < delta-TocH < gamma-CEHC < Trolox approximately gamma-TocH approximately beta-TocH < alpha-CEHC < alpha-TocH in ethanol. The antioxidants that have lower oxidation potentials ( E p) showed higher reactivities. The k s values of alpha-, beta-, gamma-, and delta-tocopherol and tocol in micelle remained constant between pH 4 and pH 10 and decreased rapidly at pH 11~12 by increasing pH value. On the other hand, the k s values of alpha-CEHC, gamma-CEHC, and Trolox showed notable pH dependence. As a result of the detailed analysis of the pH dependence of the rate constants ( k s), the structure-activity relationship in the free radical-scavenging action of the tocopherol metabolites and Trolox has been clarified.  相似文献   
29.
This report describes a spontaneous hybrid cyst in a Sprague-Dawley (SD) rat. A 52-week-old, male SD rat had a cutaneous cyst on the left mystacial pad. Histologically, the cyst wall showed infundibular differentiation with keratohyalin granules in the granular layer and matrical differentiation comprising basaloid epithelial cells with trichohyalin granules. The cyst cavity was filled with lamellar, flaky keratin and aggregates of shadow cells. Immunohistochemically, the infundibular-type epithelium was positive for cytokeratin (CK) AE1/AE3, CK KL1 and CK14 but negative for CK15, whereas the matrical-type epithelium was negative for all four CK isoforms examined. These immunohistochemical properties of the infundibular- and matrical-type epithelia were similar to those of the infundibulum and inferior segment of normal hair follicles, respectively. Based on these findings, the cyst was diagnosed as a hybrid cyst, comprising more than one type of cyst arising from various parts of the pilosebaceous unit.  相似文献   
30.
Cardiopulmonary reflexes elicited by capsaicin (CAPS) instilled into the nasal passages were determined in 6 anesthetized dogs breathing spontaneously. Nasal instillation of CAPS (10 microg/ml, 10 ml) induced: 1) apneic response characterized by an increase in expiration time; 2) bronchoconstrictor response characterized by an increase in lung resistance and a decrease in dynamic compliance; and 3) cardiovascular response characterized by a decrease in heart rate and an increase in arterial blood pressure. These reflex responses to CAPS were attenuated by pretreatment with a higher dose of CAPS (100 microg/ml, 10 ml), suggesting desensitization of CAPS-sensitive endings. These results suggest that marked cardiopulmonary reflexes are produced by nasal CAPS instillation, which may result, at least in part, from stimulation of nasal CAPS-sensitive sensory afferents.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号