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41.
In order to understand better the natural history and conservation status of the unique land-basking Hawaiian green turtle population (Chelonia sp.), intensive tagging studies were conducted at French Frigate Shoals (24°N 160 °W), a wildlife sanctuary comprising the only aggregate breeding site remaining in the 2600 km long Archipelago. Additionally, newly captured Chelonia, as well as individuals held for extended periods in display aquaria, were tagged and released around the large islands in the southeast. Tag recoveries of adults identified during the 1973 and 1974 nesting seasons documented migrations from French Frigate Shoals to the islands of Kauai, Oahu and Maui, distances of 713, 936 and 1069 km to the southeast, respectively, and to French Frigate Shoals from Lisianski Island and Pearl and Hermes Reef, distances of 834 and 1075 km to the northwest, respectively. A captive-held female released off Niihau travelled 658 km to French Frigate Shoals where nesting was recorded. Other animals released from captivity showed movement between the large islands, while those released shortly after capture remained in the same coastal area for up to 11 months. Combined results from the present study and previous intermittent taggings made since 1961 by Federal and State wildlife management personnel indicated that breeding colony members are derived from widely separated feeding areas within the archipelago and appear to be reproductively isolated from other Pacific Chelonia. Northwestern areas of the archipelago are thought to serve as important migratory stations for early life stage development.  相似文献   
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Hyaluronic acid: a novel, double helical molecule   总被引:3,自引:0,他引:3  
Films prepared from a deformable gel (or putty) of hyaluronic acid show high crystallinity and orientation in their x-ray diffraction patterns. We have derived a probable structure for the molecules in these films. This is a double helix in which two identical, left-handed strands are antiparallel to one another. Each strand has four disaccharide residues per pitch length. Although the putty is prepared at pH 2.5, at which dilute solutions of hyaluronic have exaggerated rheological properties, the double helical form can also exist at physiological pH and therefore may be a biologically important form.  相似文献   
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OBJECTIVES: To determine if chronic selegiline HCl administration affects the cardiopulmonary response to medetomidine, oxymorphone, or butorphanol in dogs. STUDY DESIGN: Prospective randomized experimental study. ANIMALS: Twenty-eight adult, random source, hound dogs weighing 21-33 kg. METHODS: Dogs were assigned to the following treatment groups: selegiline + medetomidine (MED; n = 6); placebo + MED (n = 6), selegiline + oxymorphone (OXY; n = 6); placebo + OXY (n = 6); selegiline + butorphanol (BUT; n = 7) or placebo + BUT (n = 6). Nine dogs were treated with two of the three pre-medicants. Dogs were treated with selegiline (1 mg kg(-1) PO, q 24 hours) or placebo for at least 44 days prior to pre-medicant administration. On the day of the experiment, arterial blood for blood gas analysis, blood pressure measurements, ECG, cardiac ultrasound (mM-mode, 2-D, and continuous wave Doppler), and behavioral observations were obtained by blinded observers. An IV injection of MED (750 micro g m(-2)), OXY (0.1 mg kg(-1)) or BUT (0.4 mg kg(-1)) was given. Cardiopulmonary and behavioral data were collected at 1, 2, 5, 15, 30, and 60 minutes after injection. RESULTS: Selegiline did not modify responses to any of the pre-medicant drugs. Medetomidine caused a significant decrease in heart rate (HR), cardiac output (CO), and fractional shortening (FS). Mean arterial pressure (MAP), systemic vascular resistance (SVR), and central venous pressure (CVP) were increased. Level of consciousness and resistance to restraint were both decreased. Oxymorphone did not affect MAP, CO, CVP, or SVR, but RR and PaCO(2) were increased. Level of consciousness and resistance to restraint were decreased. BUT decreased heart rate at 1 and 5 minutes. All other cardiovascular parameters were unchanged. BUT administration was associated with decreased arterial pH and increased PaCO(2). BUT decreased level of consciousness and resistance to restraint. CONCLUSIONS AND CLINICAL RELEVANCE: Although pre-medicants themselves altered cardiopulmonary and behavioral function, selegiline did not affect the response to medetomidine, oxymorphone, or butorphanol in this group of normal dogs.  相似文献   
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We developed an efficient model for responsive gels that captures large-scale, two-dimensional (2D) deformations and chemical reactions within a swollen polymer network. The 2D calculations allowed us to probe not only volume changes but also changes in sample shape. By focusing on gels undergoing the oscillatory Belousov-Zhabotinsky reaction, we observed traveling waves of local swelling that form a rich variety of dynamic patterns and give rise to distinctive oscillations in the gel's shape. The observed patterns depend critically on the gel's dimensions. The approach provides a useful computational tool for probing the dynamics of chemomechanical processes and uncovering morphological transformations in responsive gels.  相似文献   
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Reference intervals (RI) are an integral component of laboratory diagnostic testing and clinical decision‐making and represent estimated distributions of reference values (RV) from healthy populations of comparable individuals. Because decisions to pursue diagnoses or initiate treatment are often based on values falling outside RI, the collection and analysis of RV should be approached with diligence. This report is a condensation of the ASVCP 2011 consensus guidelines for determination of de novo RI in veterinary species, which mirror the 2008 Clinical Laboratory and Standards Institute (CLSI) recommendations, but with language and examples specific to veterinary species. Newer topics include robust methods for calculating RI from small sample sizes and procedures for outlier detection adapted to data quality. Because collecting sufficient reference samples is challenging, this document also provides recommendations for determining multicenter RI and for transference and validation of RI from other sources (eg, manufacturers). Advice for use and interpretation of subject‐based RI is included, as these RI are an alternative to population‐based RI when sample size or inter‐individual variation is high. Finally, generation of decision limits, which distinguish between populations according to a predefined query (eg, diseased or non‐diseased), is described. Adoption of these guidelines by the entire veterinary community will improve communication and dissemination of expected clinical laboratory values in a variety of animal species and will provide a template for publications on RI. This and other reports from the Quality Assurance and Laboratory Standards (QALS) committee are intended to promote quality laboratory practices in laboratories serving both clinical and research veterinarians.  相似文献   
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OBJECTIVE: To determine effects of selegiline hydrochloride, phenylpropanolamine (PPA), or a combination of both on physiologic and behavioral variables in dogs. ANIMALS: 40 adult hound-type dogs. PROCEDURE: Dogs were assigned to 4 groups. One group received selegiline (1 mg/kg, PO, q 24 h) and PPA (1.1 mg/kg, PO, q 8 h), a second group received selegiline alone, a third group received PPA alone, and a fourth group received neither drug. Dogs were observed 3 times/d throughout the 30-day study (daily during the first week, on alternate days during the next 2 weeks, and again daily during the final week). Observers recorded rectal temperature, pulse, respiratory rate, oscillometric blood pressure, and lead-II ECG and assessed 4 behaviors, using an analogue scale. Variables were compared among treatment groups by use of a 2-factor ANOVA with data categorized into three 10-day treatment periods. A similar comparison was made among treatment groups with data categorized by time of observation (morning, afternoon, or evening) for all study days. RESULTS: Variables did not differ among groups at study initiation. Pulse rate was the only variable that differed significantly among treatment groups during the study. During the first 10 days of treatment, dogs receiving PPA had a lower pulse rate than dogs that did not. Although signs of illness were apparent in a few dogs, illness did not appear to be related to treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Adverse effects were not detected after administration of selegiline, PPA, or a combination of the drugs in healthy dogs.  相似文献   
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