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   23篇
  免费   0篇
  5篇
综合类   2篇
农作物   1篇
水产渔业   2篇
畜牧兽医   13篇
  2022年   2篇
  2020年   1篇
  2019年   1篇
  2018年   1篇
  2013年   1篇
  2012年   1篇
  2011年   2篇
  2009年   1篇
  2008年   6篇
  2004年   2篇
  2003年   2篇
  2001年   1篇
  1999年   1篇
  1997年   1篇
排序方式: 共有23条查询结果,搜索用时 125 毫秒
1.
Captive juvenile African black-footed penguins (Spheniscus demersus) housed in an outdoor enclosure at the Baltimore Zoo have an average 50% mortality from avian malarial (Plasmodium sp.) infection each year without intense monitoring for disease and chemotherapeutic intervention. During the 1996 malaria transmission season, the safety and efficacy of an anti-circumsporozoite (CSP) DNA vaccine encoding the Plasmodium gallinaceum CSP protein against P. relictum were studied. The goal was to reduce clinical disease and death without initiating sterile immunity after release into an area with stable, endemic avian malaria. The birds were monitored for adverse clinical signs associated with vaccination, the stimulation of an anti-CSP antibody response, and protection afforded by the vaccine. The presence of P. relictum in trapped culicine mosquitoes within the penguin enclosure was monitored to assess parasite pressure. Among the vaccinated penguins, the parasitemia rate dropped from approximately 50% to approximately 17% despite intense parasite pressure, as determined by mosquito infection rate. During the year of the vaccine trial, no mortalities due to malaria occurred and no undesirable vaccination side effects occurred. This is the first trial of an antimalarial vaccine in a captive penguin colony.  相似文献   
2.
The purpose of this study was to assess the diagnostic utility of parathyroid ultrasonography to differentiate causes of hypercalcemia in dogs. We analyzed qualitative and quantitative ultrasound imaging findings and clinical pathology data from 33 dogs that underwent parathyroid ultrasound examination as part of the diagnostic evaluation for hypercalcemia. Diagnoses of the diseases causing hypercalcemia included parathyroid carcinoma (n = S), parathyroid adenoma (n = 15), parathyroid adenomatous hyperplasia (n = 6), chronic renal insufficiency (n = 3), and hypercalcemia of malignancy (n = 4). All parathyroid lesions were round or oval and hypoechoic compared with surrounding thyroid parenchyma. Adenomatous and adenocarcinomatous glands were 4 mm or larger in longest linear measurement on US examination and were statistically significantly larger than hyperplastic glands. (p < 0.001) Linear measurements of parathyroid glands acquired at the time of ultrasound examination correlated well with direct siz determination after surgical excision. (r2= 0.9, p < 0.0001) Parathyroid lesions <4 mm are highly suspicious for parathyroid adenoma or carcinoma, while US lesions <4 mm most likely represent primary adenomatous hyperplasia or secondary parathyroid hyperplasia. Parathyroid size estimation from ultrasound examination is an accurate predictor of true size.  相似文献   
3.
Degenerative disorders of motor neurons include a range of progressive fatal diseases such as amyotrophic lateral sclerosis (ALS), spinal-bulbar muscular atrophy (SBMA), and spinal muscular atrophy (SMA). Although the causative genetic alterations are known for some cases, the molecular basis of many SMA and SBMA-like syndromes and most ALS cases is unknown. Here we show that missense point mutations in the cytoplasmic dynein heavy chain result in progressive motor neuron degeneration in heterozygous mice, and in homozygotes this is accompanied by the formation of Lewy-like inclusion bodies, thus resembling key features of human pathology. These mutations exclusively perturb neuron-specific functions of dynein.  相似文献   
4.
OBJECTIVE: To determine the in vitro effect of prostaglandin (PG) E2, PGF2alpha, and the nonsteroidal anti-inflammatory drugs (NSAIDs) indomethacin, ketoprofen, and nabumetone on the contractile strength of the circular smooth muscle layer of the third compartment of the stomach of llamas. SAMPLE POPULATION: Specimens of the third compartment obtained from 5 healthy adult llamas. PROCEDURE: Full-thickness tissue samples were collected from the third compartment immediately after euthanasia. Specimens were cut into strips oriented along the circular muscle layer and mounted in a tissue bath system. Incremental amounts of ketoprofen, nabumetone, indomethacin, PGE2, and PGF2alpha were added, and contractile strength (amplitude of contractions) was recorded. RESULTS: Generally, PGE2 reduced contractile strength of the circular smooth layer of the third compartment, whereas PGF2alpha, increased the strength of contractions. The activity of the NSAIDs was generally excitatory in a concentration-dependent manner, although significant changes were induced only by administration of indomethacin. CONCLUSIONS AND CLINICAL RELEVANCE: On isolated smooth muscle strips of the third compartment of llamas, exogenous PGE2 and PGF2alpha had a variable effect on contractile strength. Administration of the NSAIDs did not inhibit contractility and would not be likely to induce stasis of the third compartment in the absence of an underlying disease process.  相似文献   
5.
A pair of Australian black swans (Cygnus atratus) with origins in Wakefield, Virginia, USA, was admitted to the quarantine area at the Baltimore Zoo for general health assessments before housing in the collections. During the quarantine period, no clinical signs of disease were manifest; however, upon examination of a blood smear, intraerythrocytic parasites were detected and initially determined to be Haemoproteus species. Diagnostic polymerase chain reaction (PCR) and sequencing results, however, indicated that the parasites were within the genus Plasmodium. Subclinical infections with Plasmodium species in birds may affect collection management, and transmission from refractory hosts to susceptible hosts should be considered when multispecies exhibits are used. In addition, changes in the dynamics of host-vector-parasite interactions might have significant impacts on wild or domesticated populations of birds.  相似文献   
6.
A sandwich enzyme-linked immunosorbent assay (ELISA) has been developed for detection of α-amylase in preharvest sprouted wheat and adapted to rapid field-use formats requiring 15–20 min to perform. Polyclonal and monoclonal antibodies were prepared to detect a mixture of high and low pI isozymes of α-amylase and high pI isozymes only. All antibodies detected α-amylase on immunoblots of either a crude wheat extract or of purified enzyme, but only the polyclonal antibodies functioned in a sandwich ELISA. Depending on the antibody combination, the tube ELISA detected either the high and low pI isozymes of α-amylase or the high pI isozymes only with a detection limit of ≈0.5–1.0 ng/mL of amylase. Wheats with falling numbers (FN) of <350 sec could be discriminated from sound wheats, with decreasing FN producing increasing assay color. Using 130 wheat grain samples, ELISA absorbances for detection of both high and low pI isozymes and of high pI isozymes only were highly positively correlated with amylase enzyme activity and negatively correlated with FN. The correlations were similar for detection of both isozyme families and for detection of high pI isozymes only. Analyses of three sets of wheat samples from different environments demonstrated that the relationship between ELISA absorbance and FN had little dependence on wheat cultivar. The precision of sample analysis using the field ELISA was similar to the precision of FN test apparatus.  相似文献   
7.
The effect of feed deprivation at four water temperatures (17, 20, 23, 26 °C) was investigated in meagre (Argyrosomus regius) of initial mean weight ± SD, 116.16?±?4.74 g, in triplicate groups. Fish were deprived of feed for a period of 60 days and sampled on days 0, 14, 41, and 60, during which body weight, specific growth rate, somatic indices, muscle proximate composition, plasma metabolite levels (total lipids, proteins, cholesterol, triglycerides, glucose), and liver and muscle enzymatic activities [L-lactate dehydrogenase (L-LDH), citrate synthase (CS), malate dehydrogenase (MDH)] were evaluated. Long-term feed deprivation resulted in a significant decrease in body weight, condition factor (CF), hepatosomatic index (HSI), muscle lipids, and plasma metabolites (all except proteins) and increase in muscle moisture. Plasma glucose concentration decreased with time and became significantly lower at 41 and 60 days. Glucose concentration and weight loss expressed a different response in the short term (14 days) than in the long term (14 and 60 days) of feed deprivation, suggesting a change in glucose metabolic profile. After 60 days of feed deprivation, there was an increase in the L-LDH activity in the liver at all temperature levels, which reflects a rising glycolytic potential by activating the carbohydrate metabolism and an ATP-dependent demand. MDH activity increased in the liver and muscle, except at 17 °C in the muscle, which indicates aerobic glycolysis and lipolysis. CS activity in the liver increased after the 60 days, whereas that in the muscle decreased, indicating the muscle is less dependent on aerobic oxidation for energy reserves.  相似文献   
8.
The objective of this study was to describe the histopathologic changes observed in extrapituitary organs as well as the pituitary glands of horses with pituitary pars intermedia dysfunction (PPID). Adrenal gland, thyroid gland, liver, lung, kidney, heart, and pituitary gland from 32 horses with clinical and histologic evidence of PPID and 20 control horses were reviewed histologically. Ten of the control horses were aged animals (≥15 years), allowing those changes attributed to age to be identified. In addition to previously reported changes in adrenal gland and liver, an association was established between PPID and several extrapituitary histopathologic changes, namely bronchiolitis, proliferative glomerulopathy, and myocardial lipofuscinosis and fibrosis. The potential biologic significance of these changes is discussed and, although the retrospective design of the current study precludes establishment of causal relationships between the observed extrapituitary changes and PPID, these findings suggest that further investigations are warranted.  相似文献   
9.
10.
As the quest for marine-derived compounds with pharmacological and biotechnological potential upsurges, the importance of following regulations and applying Responsible Research and Innovation (RRI) also increases. This article aims at: (1) presenting an overview of regulations and policies at the international and EU level, while demonstrating a variability in their implementation; (2) highlighting the importance of RRI in biodiscovery; and (3) identifying gaps and providing recommendations on how to improve the market acceptability and compliance of novel Blue Biotechnology compounds. This article is the result of the work of the Working Group 4 “Legal aspects, IPR and Ethics” of the COST Action CA18238 Ocean4Biotech, a network of more than 130 Marine Biotechnology scientists and practitioners from 37 countries. Three qualitative surveys (“Understanding of the Responsible Research and Innovation concept”, “Application of the Nagoya Protocol in Your Research”, and “Brief Survey about the experiences regarding the Nagoya Protocol”) indicate awareness and application gaps of RRI, the Nagoya Protocol, and the current status of EU policies relating to Blue Biotechnology. The article categorises the identified gaps into five main categories (awareness, understanding, education, implementation, and enforcement of the Nagoya Protocol) and provides recommendations for mitigating them at the European, national, and organisational level.  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