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991.
The study was conducted on 10 buffalo calves with a weight of 98.5 +/- 3.9 kg and age 9.7 +/- 1.3 months. Ten trials of two treatments were carried out using a randomized block design. Atropine at the dose of 0.02 mg/kg bodyweight was administered in both the groups. The animals of group I received romifidine at the dose of 10 microg/kg i.v., 10 min after atropine administration, whereas, animals of group II received triflupromazine at the dose of 0.3 mg/kg i.m. and 10 min later romifidine at the dose of 10 microg/kg i.v. immediately followed by ketamine at the dose of 5 mg/kg i.v. The onset of action of romifidine in group I occurred within 2 min and the animals remained under mild sedation for 31 +/- 4.8 min. In group II, the triflupromazine-romifidine-ketamine combination induced anaesthesia for 14 +/- 2.3 min. Hypothermia, significant bradycardia and respiratory depression was noticed in both groups at different time intervals.  相似文献   
992.
This study evaluated the suitability of invA gene amplification by PCR as an effective means of detecting Salmonella species in pigs experimentally infected with S. Typhimurium DT104. A controlled infection study using 24 pigs was performed in order to compare efficacy, precision and detection rates of the invA-based PCR method originally described by Rahn, K. De Grandis, S.A., Clarke, R.C., McEwan, S.A., Galan, J.E., Ginocchio, C., Curtiss, R. 3rd, C.L. Gyles, (Mol. Cell. Probes 1992; 6: 271-279) as a new in-house invA-based PCR method for the specific detection of Salmonella spp. in pork and different tissue samples of slaughter pigs. Finally, PCR results were compared with culture detection rates obtained by isolation procedures following the ISO 6579:2000, the 'gold standard'. After slaughtering, 14 different tissue samples of each pig were investigated to verify the usefulness of the two invA-based PCR methods in different matrices of slaughter pigs. The results demonstrate that the application of the widely used invA-based primer pair (139 + 141) may result in questionable products if samples gained from selective enrichment in the Rappaport-Vassiliadis medium were investigated. These questionable products can lead to false-positive results, if no additional hybridization procedure is attached or if unspecialized persons use this method in routine laboratory practice. The newly developed in-house PCR method used is based on the 3'-prime region of invA, especially designed and harmonized for the detection of Salmonella in different matrices of slaughtered pigs after bacterial enriched broth culture. In this study, this PCR revealed no questionable products and, furthermore, the specificity of the amplificate could be tested by means of the restriction enzyme NdeI. In comparison with the culture detection procedure, the new PCR method has a sensitivity of 100% and a specificity of 96%. Thus, this method might be used as a meaningful tool in eliminating Salmonella-positive carcasses at slaughterhouse level and thus, keeping them out of the food chain.  相似文献   
993.
The pharmacokinetic properties of clemastine were investigated in six healthy dogs and compared with the effect of the drug recorded as inhibition of wheal formation induced by intradermal injections of histamine. Clemastine clearance was high (median: 2.1 L h(-1) kg(-1)) and the volume of distribution large (13.4 L kg(-1)). The half-life after intravenous administration was 3.8 h and the plasma protein binding level in vitro was 98%. After oral administration, the bioavailability was only 3%. Given intravenously, clemastine (0.1 mg kg(-1)) inhibited wheal formation completely for 7 h, whereas the effect after oral administration (0.5 mg kg(-1)) was minor. The data show that most dosage regimens suggested in the literature for the oral administration of clemastine to dogs are likely to give too low a systemic exposure of the drug to allow effective therapy.  相似文献   
994.
This survey assessed the feline transfusion practices at the University of Berlin from 1998 to 2001 in regard to patient population, indications, efficacy, and transfusion reactions. Blood was obtained from seven healthy in-house donors and 127 mostly indoor client-owned pet cats. Over a 3-year period 91 cats were transfused with blood type compatible blood. The blood was fresh (within 8 h of collection) or stored no longer than 15 days. Transfusions were required because of blood loss anaemia (n=40), haemolytic anaemia (n=13), ineffective erythropoiesis (n=35), hypoproteinaemia (n=2) or coagulopathy (n=2). The anaemic cats had a pretransfusion haematocrit of 5-20% (m [median]=13), and received one to six transfusions (m=1). The survival rates of the anaemic cats at 1 and 10 days after transfusion were 84 and 64%, respectively. None of the deaths appeared to be related to transfusion reactions. The major crossmatch, undertaken before 117 transfusions, was incompatible for eight cats. All except for one had previously been transfused. Lysis of transfused cells in six cases resulted in a less than expected haematocrit rise and an increase in serum bilirubin. Transient mild transfusion reactions were only noted in two cats during the second or third transfusion. In conclusion, with proper donor selection and appropriate compatibility screening, blood transfusions are well tolerated, appear effective, and may increase chances of survival.  相似文献   
995.
Different barley varieties, consisting of hulled and hull-less types, of normal, waxy, and high amylose starch, as well as two-rowed and six-rowed types, were analyzed for their main proanthocyanidins and bound phenolic acids. Variations in proanthocyanidin and phenolic acid contents were studied in different barley types as well as inter-relationships between the phytochemicals and polysaccharides. The main flavanols found in the analyzed barley varieties were two dimeric as well as four trimeric forms in addition to catechin. The total amount of flavanols ranged from 325 to 527 microg/g of fresh weight of barley flour. No evident associations were found between variations in proanthocyanidin levels and different barley types. The total amount of phenolic acids ranged from 604 to 1346 microg/g of fresh weight of barley flour, with ferulic acid as the dominating acid. The amount of phenolic acids varied according to occurrence or lack of hull, with significantly higher levels in the hulled varieties.  相似文献   
996.
How does the bilingual brain distinguish and control which language is in use? Previous functional imaging experiments have not been able to answer this question because proficient bilinguals activate the same brain regions irrespective of the language being tested. Here, we reveal that neuronal responses within the left caudate are sensitive to changes in the language or the meaning of words. By demonstrating this effect in populations of German-English and Japanese-English bilinguals, we suggest that the left caudate plays a universal role in monitoring and controlling the language in use.  相似文献   
997.
Transport of metabolites across the mitochondrial inner membrane is highly selective, thereby maintaining the electrochemical proton gradient that functions as the main driving force for cellular adenosine triphosphate synthesis. Mitochondria import many preproteins via the presequence translocase of the inner membrane. However, the reconstituted Tim23 protein constitutes a pore remaining mainly in its open form, a state that would be deleterious in organello. We found that the intermembrane space domain of Tim50 induced the Tim23 channel to close. Presequences overcame this effect and activated the channel for translocation. Thus, the hydrophilic cis domain of Tim50 maintains the permeability barrier of mitochondria by closing the translocation pore in a presequence-regulated manner.  相似文献   
998.
The endemic species richness on Madagascar, relative to landmass area, is unparalleled in the world. Many organisms on the island have restricted geographical ranges. A comprehensive hypothesis explaining the evolution of this microendemism has yet to be developed. Using an analysis of watersheds in the context of Quaternary climatic shifts, we provide a new mechanistic model to explain the process of explosive speciation on the island. River catchments with sources at relatively low elevations were zones of isolation and hence led to the speciation of locally endemic taxa, whereas those at higher elevations were zones of retreat and dispersion and hence contain proportionately lower levels of microendemism. These results provide a framework for biogeographic and phylogeographic studies, as well as a basis for prioritizing conservation actions of the remaining natural forest habitats on the island.  相似文献   
999.
Quantifying long-range dissemination of infectious diseases is a key issue in their dynamics and control. Here, we use influenza-related mortality data to analyze the between-state progression of interpandemic influenza in the United States over the past 30 years. Outbreaks show hierarchical spatial spread evidenced by higher pairwise synchrony between more populous states. Seasons with higher influenza mortality are associated with higher disease transmission and more rapid spread than are mild ones. The regional spread of infection correlates more closely with rates of movement of people to and from their workplaces (workflows) than with geographical distance. Workflows are described in turn by a gravity model, with a rapid decay of commuting up to around 100 km and a long tail of rare longer range flow. A simple epidemiological model, based on the gravity formulation, captures the observed increase of influenza spatial synchrony with transmissibility; high transmission allows influenza to spread rapidly beyond local spatial constraints.  相似文献   
1000.
Kutschera U 《Science (New York, N.Y.)》2006,311(5763):952-4; author reply 952-4
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