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131.
Compounds that prevent chloride transport in membrane vesicles have been tested for in vivo activity against the effects of intestinal secretory agents. Chloride channel blockers including diphenylamine-2-carboxylate, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonate, 5-nitro-2-(2-phenylethylamino)benzoic acid, and alpha-phenylcinnamic acid were tested for effects on jejunal or ileal secretion in weanling pigs. Secretion was studied in ligated intestinal loops in a control state, during exposure to secretory concentrations of theophylline, and after prior treatment with cholera toxin. Increases in net fluid flux induced by either theophylline or cholera toxin were not prevented by adding chloride channel blockers into the intestinal lumen. Channel blocker concentrations that reduced chloride transport by greater than 50% in pig jejunal brush border vesicles did not cause significant changes in unidirectional blood to lumen chloride flux measured in situ. Several routes of administration of the specific chloride channel blocker alpha-phenylcinnamate failed to reduce fluid secretion induced by theophylline. Chloride channel blocker effectiveness appears to be significantly different between in vitro and in vivo experimental models. In contrast to the chloride channel blockers, loperamide significantly reduced net fluid and chloride flux in ileal loops secreting fluid in response to theophylline. Antagonism of the production or actions of second messenger by loperamide was more effective than the chloride channel blockers in reducing conductive chloride transport associated with intestinal secretion.  相似文献   
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Tropical Animal Health and Production - The objective of this study was to evaluate intake, digestibility, microbial protein production, and nitrogen balance of lambs fed with different dehydrated...  相似文献   
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The aim of this study was to determine serum levels of natriuretic peptide precursors (NT‐proANP and NT‐proBNP) during pregnancy in brachycephalic bitches. Fifteen healthy multiparous bitches were selected for this prospective study. Serum levels of NT‐proANP and NT‐proBNP were measured during anoestrous and at 14, 35, 42, 49 and 56 days (2nd, 5th, 6th, 7th and 8th weeks) of pregnancy. Fourteen animals had normal gestations, and one bitch developed single foetus syndrome. The natriuretic peptide levels of this animal were not included in this study; however, it is important to report that its NT‐proANP levels were four times greater than those of normal patients. There was no significant difference (p = 0.072) in NT‐proBNP levels between anoestrous (0.20 ± 0.10 ng/ml) and the different pregnancy weeks (0.27 ± 0.12 ng/ml). There was a positive correlation (p < 0.0001) between NT‐proANP and gestational age, and the levels of this marker increased significantly (p < 0.0001) during the 6th (0.26 ± 0.06 ng/ml), 7th (0.28 ± 0.04 ng/ml) and 8th weeks (0.29 ± 0.05 ng/ml) when compared to anoestrous (0.18 ± 0.02 ng/ml). NT‐proANP serum levels are correlated with gestational development and may be indicative of cardiovascular adaptation in canine brachycephalic pregnancy.  相似文献   
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The aim was to compare the early luteal development in ewes superovulated with different doses of pFSH. Twenty‐nine Santa Inês ewes received a progesterone device (CIDR®) for 8 days. Gonadotrophic treatment started on Day 6: G200 (control, n = 9, 200 mg); G133 (n = 10, 133 mg); and G100 (n = 10, 100 mg of pFSH). On Day 6, all females received eCG (300 IU). B‐mode and spectral Doppler ultrasonography were performed daily during the early luteal phase (Days 11–15) to monitor the development of corpora lutea (CLs; dimensions) and ovarian arteries indices. CLs were also classified as normal or prematurely regressed (PRCL) on Day 15 by videolaparoscopy. Ewes from G100 and G133 showed gradual increase in luteal diameter during the early luteal phase (p < 0.001), whereas G200 animals presented increase from Day 11 to Day 13, and then decrease on Days 14 and 15 (p < 0.001). The G200 females showed greater percentage of PRCL (45.20%) than those of the other groups (p < 0.001). The normal CLs number was greater in G100 than in G133 (p = 0.04), while the PRCL number was greater in G200 than in the other groups (p = 0.03). Resistive index (RI) was greater in G200 than in G100 (p = 0.02). RI was lower in Day 12 than Day 15 (p = 0.02). Pulsatility index (PI) was greater on Days 14 and 15 (p < 0.01). In conclusion, the lowest dose of pFSH (100 mg) can be considered sufficient for an efficient superovulatory response in sheep, producing better CLs development dynamic in early luteal phase and ovarian blood perfusion and smaller number of PRCL than the traditional (200 mg) pFSH dose.  相似文献   
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The study aimed to describe the Bubalus bubalis seminal plasma proteome using a label‐free shotgun UDMSE approach. A total of 859 nonredundant proteins were identified across five biological replicates with stringent identification. Proteins specifically related to sperm maturation and protection, capacitation, fertilization and metabolic activity were detected in the buffalo seminal fluid. In conclusion, we provide a comprehensive proteomic profile of buffalo seminal plasma, which establishes a foundation for further studies designed to understand regulation of sperm function and discovery of novel biomarkers for fertility. MS data are available in the ProteomeXchange with identifier PXD003728.  相似文献   
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