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31.
Our objective was to study reproductive consequences of lactation bodyweight loss occurring in primiparous sows with mild feed restriction and to relate these lactation weight losses and its consequences to metabolic profiles during lactation and subsequent early gestation. After weaning, 47 first‐litter sows were retrospectively assigned to a high– (HWL, >13.8%, n = 24) or low (LWL, ≤13.8%, n = 23)–weight loss group. Thirty‐six animals received an indwelling jugular vein catheter to determine lactational and gestational profiles of insulin‐like growth factor‐1 (IGF‐1), non‐esterified fatty acids (NEFA) and urea and gestational profiles of progesterone. At day 35 after insemination, sows were euthanized and their reproductive tract collected. Pregnancy rate was 75% (18/24) for HWL and 96% (22/23) for LWL sows. High–weight loss sows had a lower number of implantation sites (17.2 ± 0.8 vs 19.5 ± 0.7, respectively, p = 0.03) and a lower embryonic survival (65.6 ± 3.4 vs 77.4 ± 2.9%, p = 0.02), resulting in fewer vital embryos (14.9 ± 0.9 vs 16.8 ± 0.7, p = 0.07) than LWL sows. Progesterone peak values were reached later in HWL than in LWL sows (day 13.4 ± 0.5 vs 12.0 ± 0.5, respectively, p = 0.05). Gestational concentrations of IGF‐1, NEFA and urea were almost identical for HWL and LWL sows, whilst numerical differences were seen during lactation. The current study shows negative consequences of lactational weight loss in mildly feed‐restricted primiparous sows for embryonic survival and shows that these consequences seem only mildly related with metabolic alterations during lactation and not with metabolic alterations during subsequent gestation.  相似文献   
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Cryptosporidiosis is a common opportunistic infection in the gastrointestinal tract of human and nonhuman primates with AIDS. Pulmonary infection associated with Cryptosporidium spp. has not been previously reported in monkeys. Two macaques experimentally infected with simian immunodeficiency virus (SIV) had lesions containing cryptosporidial organisms involving the trachea, lungs, bile ducts, pancreas, and intestine. The pulmonary sections revealed moderate to severe bronchopneumonia associated with cryptosporidiosis. Numerous 2-4 microm oval Cryptosporidium spp. organisms were present in the cytoplasm of alveolar macrophages, multinucleated giant cells, and intestinal epithelial cells. Giant cells were positive for SIV by in situ hybridization. These are the first reported cases of cryptosporidiosis with involvement of pulmonary parenchyma in SIV-infected macaques.  相似文献   
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The purpose of this study was to evaluate the effect of cooling ovarian tissue on pig pre-antral follicles. Ovaries were maintained in saline solution (0.9%) at 4 or 20 degrees C for 6, 12 or 18 h. After storage, pre-antral follicles were morphologically evaluated. While primordial follicles were not affected by the storage, the percentage of morphologically normal growing follicles was significantly reduced in ovarian tissue stored at 20 degrees C for 12 or 18 h. To test the viability of stored follicles, growing follicles isolated from ovaries stored at 4 degrees C for 18 h and at 20 degrees C for 6 h were cultured for 3 days. Follicles stored in either condition presented the same growth pattern in vitro as fresh follicles. We conclude that storage of pig ovaries at 4 degrees C for up to 18 h or at 20 degrees C for up to 6 h does not affect the morphology of growing follicles or their ability to grow in vitro.  相似文献   
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There is a growing need for both science and practice domains to collaboratively and systematically seek knowledge-based strategies for sustainable development.In recent years,transdisciplinary research has emerged as a new approach that enables joint problem solving among scientists and stakeholders in various fields. In this paper,we aim to introduce transdisciplinary research for supporting the integration of the concept of ecosystem services into land and water management in the Tarim River Basin,Xinjiang,Northwest China.While a large number of ecosystem service studies have helped to raise the awareness for the value of nature in China,a number of challenges remain,including an improved understanding of the relationships between ecosystem structure, functions and services,and the interaction of the various ecosystem services.A meaningful valuation of ecosystem services also requires the consideration of their strong spatial heterogeneity.In addition,ways to introduce the concept of ecosystem services into decision-making in China need to be explored.Thus,successful integration of the concept of ecosystem services into actual land and water management requires a broad knowledge base that only a number of scientific disciplines and stakeholders can provide jointly,via a transdisciplinary research process.We regard transdisciplinary research as a recursive process to support adaptive management that includes joint knowledge generation and integration among scientists and stakeholders.System,target,and transformation knowledge are generated and integrated during the process of(1)problem(re)definition,(2)problem analysis and strategy development,and(3)evaluation of the impact of the derived strategy.Methods to support transdisciplinary research comprise participatory modelling(actor-based modelling and Bayesian Networks modelling)and participatory scenario development.Actor-based modelling is a semi-quantitative method that is based on the analysis of problem perspectives of individual stakeholders as depicted in perception graphs.With Bayesian Networks,complex problem fields are modelled probabilistically in a simplified manner,using both quantitative data and qualitative expert judgments.These participatory methods serve to integrate diverse scientific and stakeholder knowledge and to support the generation of actually implementable management strategies for sustainable development.For the purpose of integrating ecosystem services in land and water management in the Tarim River Basin through transdisciplinary research,collaboration among scientists and institutional stakeholders from different sectors including water,agriculture,forestry,and nature conservation is required.The challenge is to adapt methods of transdisciplinary research to socio-cultural conditions in China,particularly regarding ways of communication and decision-making.  相似文献   
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Pneumocystis carinii (PC) pneumonia is a frequent manifestation of the acquired immunodeficiency syndrome (AIDS) in humans and macaques. An unusual nodular type of PC pneumonia was observed in two simian immunodeficiency virus (SIV)-inoculated rhesus macaques (Macaca mulatta). These animals developed clinical signs of simian AIDS, including anorexia, weight loss, dyspnea, and collapse. Grossly, both animals had multifocal tan-white nodules 1-10 mm in diameter scattered throughout the lungs. One animal had similar nodules involving the diaphragm and thoracic wall. The lungs were characterized by severe PC pneumonia with numerous large nodules consisting of foamy material that compressed adjacent tissue. The nodules had central areas of necrosis and lysis of alveolar septa. Varying degrees of necrotizing vasculitis were observed in areas of nodular PC pneumonia. The presence of PC in intra-alveolar spaces and nodular lesions was confirmed by immunohistochemistry. No evidence of other agents, including viral inclusions, bacteria, fungi, and lung mites, was detected. The animal with the most severe nodular PC pneumonia had vascular involvement with extrapulmonary spread to the diaphragm, thoracic wall, and regional lymph nodes. This unusual type of nodular PC pneumonia has been rarely seen in human AIDS patients.  相似文献   
38.
Elevated ocean temperatures have been predicted to lead to a poleward shift in the latitudinal distribution ranges of fish species. Different responses of fish species to increased temperatures might lead to changes in assemblage structure and local species richness. In this study, the assemblage structure and diversity of groundfish in Icelandic waters were examined using data from a standardized groundfish survey conducted annually in 1996–2007. We used hierarchical cluster analysis to define assemblages in two time periods and canonical correspondence analysis to explore the relationships between the assemblages and temperature, depth, latitude, longitude and year. We further used two estimates of diversity, species richness and the Shannon index. Four major species assemblages were identified. Assemblages in the hydrographically stable deep waters north of the country were consistent during the study, while assemblage structure in the more variable shallow waters underwent some changes. For this period of generally increasing sea temperature, the canonical correspondence analysis also revealed a shift towards species representative of warmer temperatures. Diversity was shown to be highly variable both temporally and spatially, and also to vary with depth and temperature. Species richness increased with temperature and time southwest of the country, but decreased northeast of the country. The different trends detected between the northern and southern areas illustrate the importance of performing analyses at the most appropriate scale.  相似文献   
39.
To clarify the clinicopathological features of canine epulides, 189 epulides were reviewed retrospectively. The incidence of the fibromatous, ossifying, acanthomatous and giant cell epulides were 56.6% (107/189), 23.3% (44/189), 18.0% (34/189) and 2.1% (4/189), respectively. The average ages of dogs with fibromatous, ossifying, acanthomatous and giant cell epulides were 8.8, 8.4, 7.8 and 8.7 years, respectively. The male/female ratio of dogs with the acanthomatous epulis (0.8) was lower than those of dogs with the fibromatous (1.9), ossifying (1.4) and giant cell epulis (3.0). There were slight breed differences among the types of epulides. The most noticeable result was that 38.2% of the acanthomatous epulis occurred in Shetland sheepdogs. 43.9% of the fibromatous epulis and 52% of the ossifying epulides arose around maxillary premolars, while 58.8% of the acanthomatous epulis arose around the mandibular canines. Dogs with the fibromatous and ossifying epulides had more severe dental plaque deposition than those with the acanthomatous epulides. Few of the fibromatous (6/104) or ossifying epulides (4/44) showed recurrence after excision, while the majority (21/23) of the acanthomatous epulides showed rapid and repeated recurrences after surgical excision. Epulides treated with hemimandibulectomy or bleomycin chemotherapy did not recur. Giant cell epulides showed no recurrence after surgical removal. These results indicate that the acanthomatous epulis differed from other types of epulides in biological and morphological features and poor prognosis.  相似文献   
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