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An investigayion was made into the status of the Morelet's crocodile Crocodylus moreleti Dumeril & Dumeril in Belize, a Caribbean nation of Central America. Juvenile animals were found to be rather common in isolated areas, but very few adults were observed; we believe this to be an indication of over-exploitation. Certain aspects of the hide-hunting-dealing enterprise are also examined, and it is concluded that if C. moreleti is to survive in any numbers, a policy of protection should be instituted.  相似文献   
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Florida manatees (Trichechus manatus latirostris) are exposed to many conditions in their habitat that may adversely impact health and impair immune function in this endangered species. In an effort to increase the current knowledge base regarding the manatee immune system, the production of an important reactive nitrogen intermediate, nitric oxide (NO), by manatee peripheral blood mononuclear cells (PBMC) was investigated. PBMC from healthy captive manatees were stimulated with LPS, IFN-gamma, or TNF-alpha, either alone or in various combinations, with NO production assessed after 24, 48, 72, and 96 h of culture. NO production in response to LPS stimulation was significantly greater after 48, 72, or 96 h of culture compared to NO production after 24h of culture. A specific inhibitor of inducible nitric oxide synthase (iNOS), L-NIL (L-N(6)-(1-iminoethyl)lysine), significantly decreased NO production by LPS-stimulated manatee PBMC. Manatee specific oligonucleotide primers for iNOS were designed to measure expression of relative amounts of mRNA in LPS-stimulated manatee PBMC from captive manatees. NO production by PBMC from manatees exposed to red tide toxins was analyzed, with significantly greater NO production by both unstimulated and LPS stimulated PBMC from red tide exposed compared with healthy captive or cold-stress manatees. Free-ranging manatees produced significantly lower amounts of nitric oxide compared to either captive or red tide rescued manatees. Results presented in this paper contribute to the current understanding of manatee immune function and represent the first report of nitric oxide production in the immune system of a marine mammal.  相似文献   
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Natriuretic peptides are useful in diagnosing heart failure in dogs. However, their usefulness in detecting early stages of myxomatous mitral valve disease (MMVD) has been debated. This study evaluated N-terminal (NT) fragment pro-atrial natriuretic peptide (NT-proANP) and NT-pro-brain natriuretic peptide (NT-proBNP) in 39 Cavalier King Charles Spaniels (CKCS) with pre-clinical mitral valve regurgitation (MR), sixteen dogs with clinical signs of heart failure (HF) and thirteen healthy control dogs. Twenty seven CKCS and ten control dogs were re-examined 4 years after the initial examination and the status of the dogs 5 years after the initial examination was determined by telephone calls to the owner. All dogs were evaluated by clinical examination and echocardiography. CKCS with severe MR had higher NT-proANP and NT-proBNP compared to controls and CKCS with less severe MR. Dogs with clinical signs of HF had markedly elevated NT-proANP and NT-proBNP. Plasma concentrations of the natriuretic peptides measured at re-examination could predict progression in regurgitant jet size.  相似文献   
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OBJECTIVE: To develop a model of low urethral pressure incontinence and compare the relative contributions of the pudendal and hypogastric nerves with urethral function by performing selective neurectomy and ovariohysterectomy in dogs. ANIMALS: 19 healthy Foxhounds. PROCEDURE: Dogs were allocated into 2 groups. The first group (10 dogs) underwent bilateral hypogastric neurectomy and ovariohysterectomy and subsequent bilateral pudendal neurectomy. The second group (9 dogs) underwent bilateral pudendal neurectomy and subsequent hypogastric neurectomy and ovariohysterectomy. Urethral pressure profilometry and leak point pressure (LPP) tests were performed before and after each neurectomy. RESULTS: Before surgery, mean +/- SD LPP and maximal urethral closure pressure (MUCP) in all dogs were 169.3 +/- 24.9 cm H2O and 108.3 +/- 19.3 cm H2O, respectively; these values decreased to 92.3 +/- 27 cm H2O and 60.7 +/- 20.0 cm H2O, respectively, after both selective neurectomy surgeries. There was a progressive decline of LPP after each neurectomy; however, MUCP decreased only after pudendal neurectomy. Fifteen dogs had mild clinical signs of urinary incontinence. All dogs appeared to have normal bladder function as indicated by posturing to void and consciously voiding a full stream of urine. Urinary tract infection did not develop in any dog. CONCLUSIONS AND CLINICAL RELEVANCE: Hypogastric and pudendal neurectomy and ovariohysterectomy caused a maximum decrease in LPP whereas pudendal neurectomy caused a maximum decrease in MUCP. IMPACT ON HUMAN MEDICINE: This model may be useful for evaluation of treatments for improving urinary control in postmenopausal women.  相似文献   
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