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91.
The injection of hemolyzed blood into the venous system of the dog produced a rise in the pulmonary arterial pressure and a fall in the systemic arterial pressure. There were variable changes in the heart rate. Comparison with serotonin injections indicated that the above responses were produced by factors other than serotonin.  相似文献   
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Azoospermia is a common finding in male alpacas which present for infertility. The challenge is to differentiate azoospermia of testicular origin from non‐testicular origin. In several species, alkaline phosphatase (AP) concentrations in seminal plasma have been used as a diagnostic marker of contributions of the testis and epididymis to the ejaculate. The purpose of this study was to determine whether AP assay could differentiate testicular from non‐testicular azoospermia in male alpacas. An experimental model of bilateral outflow obstruction (pre‐scrotal vasectomy) was used in 22 male alpacas, aged 2–9 years. No reproductive history was available. Animals were submitted for electroejaculation (EE) under general anaesthesia and vasectomy performed. Five weeks later, animals were submitted for EE. Vasectomy was not successful in one animal, which was removed from analysis. AP levels were compared in seminal plasma in the pre‐ and post‐vasectomy samples. The mean ± SEM concentration of AP in pre‐vasectomy seminal plasma was 504.29 ± 166.45 U/l (range 10–2910); the post‐vasectomy levels were 252.48 ± 81.77 U/l (range 0–1640; p = 0.06). In 71.4% of animals, AP levels decreased, varying from 18% to 100% reduction. Results of this study suggest that AP is not produced exclusively by the testis and epididymis in alpacas and that AP assay is not a valid diagnostic test for determination of origin of azoospermia; the gold standard for diagnosis of origin of azoospermia remains testicular biopsy.  相似文献   
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The emergence of marine toxins in water and seafood may have a considerable impact on public health. Although the tendency in Europe is to consolidate, when possible, official reference methods based on instrumental analysis, the development of alternative or complementary methods providing functional or toxicological information may provide advantages in terms of risk identification, but also low cost, simplicity, ease of use and high-throughput analysis. This article gives an overview of the immunoassays, cell-based assays, receptor-binding assays and biosensors that have been developed for the screening and quantification of emerging marine toxins: palytoxins, ciguatoxins, cyclic imines and tetrodotoxins. Their advantages and limitations are discussed, as well as their possible integration in research and monitoring programs.  相似文献   
96.
Electron microscopy of living insects   总被引:1,自引:0,他引:1  
Electron micrographs of living specimens of the various developmental stages of the insect Tribolium confusum have been obtained with a scanning electron microscope. In most cases the specimens resumed their normal activity after being examined with the electron microscope and under went metamorphosis into the next stage.  相似文献   
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Objectives   To describe the morbidity and mortality patterns and identify factors associated with morbidity in pre-weaning llamas and alpacas.
Design   Cross-sectional observational study of 287 crias born on four farms in Ohio, USA
Procedure   Historical data representing all crias born over a 6-year period were obtained from two llama farms and two alpaca farms in Ohio. Multivariable generalised linear mixed effects regression models were used to identify factors associated with morbidity outcomes.
Results   In total, 105 (37%) of the llamas and alpacas had some reported morbidity during the pre-weaning period, and mortality rate was 2.1%. In addition, 51 (18%) of llamas and alpacas experienced morbidity because of infectious disease, and 47 (16%) experienced morbidity during the neonatal period. The three most commonly reported morbidity events were undifferentiated diarrhoea (23%), umbilical hernia (16%) and unspecified infectious disease (15%). Difficult birth was an important risk factor for pre-weaning morbidity in this population.
Conclusions   Camelid veterinarians and their clients can expect that pre-weaning health events are common among crias, although mortality is low. Crias experiencing difficult births may require additional monitoring for health events during the pre-weaning period.  相似文献   
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