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581.
This study was conducted to purify a tissue inhibitor of metalloproteinase (TIMP)-1 in a serum-free medium conditioned with bovine oviduct epithelial cells (BOEC) and to evaluate its effect on development of "HanWoo" (Bos taurus coreanae) embryos to the blastocyst stage. In the first study using SDS-PAGE electrophoresis, the presence of 32 kDa proteins, which contains TIMP-1, was detected in the medium conditioned with BOEC, and TIMP-1 was then purified from the medium by gel filtration and HPLC techniques. When examined TIMP-1 secretion, fluorescent foci indicating the secretion of TIMP-1 were found after stained BOEC with fluorescein isothiocyanate. In the next experiment, two-cell embryos derived from in vitro-fertilization were cultured in a serum-free medium, to which 0, 1.25, 2.5 or 5 microg/ml of purified TIMP-1 was supplemented. More (P<0.05) embryos developed to the morula and blastocyst stages after the addition of 2.5 microg/ml to culture medium than after no addition. In conclusion, our data indicate that BOEC secrete TIMP-1 and this glycoprotein promotes the prehatched development of "HanWoo" embryos derived from in vitro-fertilization.  相似文献   
582.
A simple, non-microscopic method was developed for the direct detection of Trichinella spiralis in pork. Samples of meat were treated with pepsin for 2 h to liberate the larvae, and sonicates were made from the deposit and used in an antigen detection system. In this system, latex particles, sensitized with a parasite-specific monoclonal antibody, were utilized in a slide or tube agglutination test. The efficiencies of these immunological methods were compared with that of trichinelloscopy in the examination of 102 pork specimens, 35 of which contained varying numbers of larvae after enzymatic digestion of 2 g of the meat. Trichinelloscopy detected 77.1% of these positive samples, but this was lower (55.5 and 41.7%) for those samples with a low larval burden (less than 50 or less than 10 larvae g-1 tissue, respectively). Better results (88.6, 76.5 and 60.0%) were obtained with the slide latex agglutination technique. The efficiency of detection was further improved (100%) using the more sensitive tube agglutination method. However, this was based on a small number (20) of samples examined and the limit of detection of this technique was subsequently found to be three larvae in total. No false-positives were seen with the latex agglutination methods from a total of 67 uninfected specimens examined.  相似文献   
583.
Effective vaccinations against swine influenza reduce the economic loss of pig industries, and also may minimize the possibility of emergence of new pandemic viruses, since pigs are intermediate hosts to generate reassortant viruses among avian and mammalian influenza viruses. In this study, we showed that intranasal immunization of pigs with formalin-inactivated or ether-split influenza vaccine (A/Aichi/2/68) induced virus-specific IgG, IgM, and IgA antibodies in their nasal secretions and sera, resulting in complete protection from virus challenge. Antibody response to the challenge virus was not observed in the immunized pigs, suggesting that the replication of the virus in the primary targets, respiratory epithelial cells, was inhibited. The present results indicate that intranasal immunization of pigs with inactivated vaccines is effective to control swine influenza, and also provide a good model, as well as a mouse model, to evaluate an intranasal application of influenza vaccine for humans.  相似文献   
584.
Australia exports 75% of the wheat produced annually, and the Asian region is an important export market for Australian wheat. These markets require suitable quality grain for use in wheat‐based products, so the understanding of wheat end products from an Asian consumer point of view is important. The major wheat quality requirements for char siew bao, a Chinese Guangdong‐style steamed bun, were determined. The research 1) developed laboratory methods for the production and assessment of char siew bao using a scoring system; 2) optimized the new methods and compared the new methods with a traditional method; and 3) used the new validated methods in an investigation of the role of soft wheat quality on char siew bao. A sponge‐and‐dough method with 1 hr fermentation time was developed to establish a simplified laboratory method for char siew bao production. The screening experiments and response surface methodology experiments showed that water addition, sugar, and sponge mixing time were responsible for 69% of the variation in total score. Dough strength was the most important parameter affecting char siew bao quality, followed by flour swelling volume, protein content, and dough extensibility. Both protein and starch quality were important determinants of char siew bao quality.  相似文献   
585.
Based on the model–data comparison at the eddy-covariance observation sites from CarboEastAsia datasets, we report the current status of the terrestrial carbon cycle modeling in monsoon Asia. In order to assess the modeling performance and discuss future requirements for both modeling and observation efforts in Asia, we ran eight terrestrial biosphere models at 24 sites from 1901 to 2010. By analyzing the modeled carbon fluxes against the CarboEastAsia datasets, the strengths and weaknesses of terrestrial biosphere modeling over Asia were evaluated. In terms of pattern and magnitude, the carbon fluxes (i.e., gross primary productivity, ecosystem respiration, and net ecosystem exchange) at the temperate and boreal forest sites were simulated best, whereas the simulation results from the tropical forest, cropland, and disturbed sites were poor. The multi-model ensemble mean values showed lower root mean square errors and higher correlations, suggesting that composition of multiple terrestrial biosphere models would be preferable for terrestrial carbon budget assessments in Asia. These results indicate that the current model-based estimation of terrestrial carbon budget has large uncertainties, and future research should further refine the models to permit re-evaluation of the terrestrial carbon budget.  相似文献   
586.
587.
Malaysia is a non‐endemic country for hepatitis E virus (HEV) infection. However, seroprevalence as high as 50% among samples of aboriginal people were reported over two decades ago. A total of 207 samples collected from seven aboriginal villages in rural settlements across two states in Malaysia were analysed for anti‐HEV IgG and IgM by an enzyme‐linked immunoassay. Following the detection of anti‐HEV seroprevalence, we organized health outreach to inform and educate the community. Qualitative interviews were conducted with individuals tested positive for anti‐HEV antibodies. Data derived from interviews and observations were used to investigate possible lifestyle behaviours associated with HEV infection. Anti‐HEV IgG was detected in six samples (5.9%) from the village of Dusun Kubur. Qualitative inquiry and observation study revealed poor dietary and household hygiene, contaminated food and water, contact with animal faeces, unsanitary and domestic waste disposal, and wildlife reservoirs could be the contributing factors for transmission and acquisition of HEV infection. Investigation during health outreach is important to provide insights for future empirical research and implementation for improvement of lifestyle behaviours among the aborigines. Managing the risk of HEV infection in the aborigines may reduce the risk of HEV transmission to the local communities.  相似文献   
588.
589.
A 36-y-old white rhinoceros (Ceratotherium simum) was presented with respiratory distress, sanguineous vaginal exudate, and anorexia. The clinical signs progressed over 40 d, and the rhinoceros died. Autopsy revealed significant ascites; a unilateral, 12.5-cm diameter, polypoid mass in the left ovary; a white, firm transmural mass in the right uterine horn; a white, friable mass in the lung; and white-to-tan, friable small nodules in the diaphragm. Histologic examination revealed similar neoplastic cells in the masses in all 4 locations, composed predominantly of epithelial cells proliferating in a tubulopapillary pattern with significant nuclear atypia and numerous atypical mitotic figures (18–42 per 2.37 mm2). Immunohistochemistry for CK7 (cytokeratin 7) and CK20 (cytokeratin 20) suggest that the ovarian, pulmonary, and diaphragmatic lesions were of ovarian origin and that the ovary was the primary tumor site.  相似文献   
590.
A 2‐year‐old female spayed Great Dane presented for inappetence and lethargy. Abdominal radiographs revealed a severely gas‐distended segment of colon. Computed tomography was performed and characterized a 180° anticlockwise colonic torsion with entrapment in a mesenteric/omental rent without vascular compromise. Exploratory laparotomy confirmed entrapment, but not colonic torsion. Computed tomography provided important information to assist clinical management decisions for this dog with colonic entrapment.  相似文献   
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