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51.
The amplitude of the parity-nonconserving transition between the 6S and 7S states of cesium was precisely measured with the use of a spin-polarized atomic beam. This measurement gives Im(E1pnc)/beta = -1.5935(56) millivolts per centimeter and provides an improved test of the standard model at low energy, including a value for the S parameter of -1.3(3)exp (11)theory. The nuclear spin-dependent contribution was 0.077(11) millivolts per centimeter; this contribution is a manifestation of parity violation in atomic nuclei and is a measurement of the long-sought anapole moment.  相似文献   
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The compound eye of the cockroach Periplaneta has receptors for ultraviolet light (maximum sensitivity at 365 nanometers) and green light (maximum sensitivity at 510 nanometers). Single photoreceptor cells in the compound eye were impaled, identified by spectral response, and marked with dye-filled microelectrodes. Using two diferent dyes, we showed that both types of receptors can be found in the same ommatidium.  相似文献   
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CASE HISTORY: A feral cat captured in the Manawatu region of New Zealand was treated for worms and fleas, and kept confined in a metabolic cage. It showed good appetite and weight gain but had intermittent watery, yellow diarrhoea.

CLINICAL FINDINGS: Clinical examination under sedation was unremarkable and routine blood tests showed no significant abnormalities. The cat was negative for feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV). Different canned cat foods did not alter the course of the diarrhoea, and the cat was euthanised 6 months after capture. At necropsy, two sections of adult Spirometra tapeworms were found in the jejunum and typical Spirometra eggs were found in colonic contents. Molecular identification of the parasite was undertaken, using the cytochrome- c oxidase subunit-1 gene (cox1) sequence.

DIAGNOSIS: Chronic intermittent diarrhoea associated with Spirometra erinacei / S. erinaceieuropaei infection.

CLINICAL RELEVANCE: Spirometra has not been reported in New Zealand before but has been associated with gastrointestinal disease in cats in other parts of the world. It requires speciestargeted treatment to be eliminated effectively, and is zoonotic. Diagnosis could be diffi cult for clinicians who are not familiar with the parasite and its life cycle.  相似文献   
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Our objective was to summarize information on the diagnostic accuracy, in terms of test sensitivity (Se) and specificity (Sp), for bovine tuberculosis (bTb) tuberculin skin tests as currently used in the United States. Meta-analyses including Se and Sp estimates from field studies of bTb tuberculin tests conducted in North American cattle were conducted to provide a distribution of estimates and central tendency for Se and Sp of the caudal fold tuberculin (CFT) and serial interpretation of the CFT and comparative cervical tuberculin (CFT-CCT) tests. In total, 12 estimates for CFT and CFT-CCT test Se and Sp were identified from seven publications matching inclusion criteria. Estimates for CFT test Se ranged from 80.4% to 93.0% and CFT test Sp from 89.2% to 95.2%. Estimates for CFT-CCT test Se ranged from 74.4% to 88.4% and CFT-CCT test Sp ranged from 97.3% to 98.6%. These distributions of test Se and Sp are intended to provide a more realistic representation for U.S. bTb skin tests than previously reported. Estimation and discussion of herd-level CFT and CFT-CCT test parameters is also included. These results should be considered at the herd and individual animal level when evaluating results from tuberculin skin test results in North American cattle herds.  相似文献   
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A 9-year-old dog was presented with generalized extensive pulmonary mineralization associated with exertional dyspnea and cyanosis. The differential diagnosis for the pulmonary mineralization included metastaticand dystrophic pulmonary calcification, atypical pulmonary neoplasia, alveolar microlithiasis, idiopathic pulmonary mineralization, and idiopathic pulmonary ossification. The dog was euthanized at the owner's request. The histologic diagnosis was idiopathic pulmonary ossification. No previous report of generalized extensive idiopathic pulmonary ossification was found. Idiopathic pulmonary ossification occurs in man, usually involves a limited area of lung, and is functionally unimportant. The pulmonary ossification in the dog reported here was generalized and associated with severe pulmonary dysfunction. The disease in man and that in the dog in this report do not appear to be directly comparable.  相似文献   
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Oxyglobin (OXY) is a hemoglobin‐based oxygen carrier (HBOC) made of glutaraldehyde‐polymerized bovine hemoglobin (bHb). Products similar to OXY are under development for use as temporary blood substitutes in trauma, shock and anemia. Since they all may increase blood O2‐carrying capacity and thus, possibly tissue oxygenation, they may also be used to enhance performance of both equine and human athletes. That is why HBOCs are banned from use in athletic competition. Our goal was to determine the pharmacokinetics of OXY after intravenous (IV) infusion to horses. Blood and urine samples were collected from adult horses that received an IV dose of 32.5 g of OXY. Concentrations of OXY in plasma and urine were quantified using a newly developed LC/Q‐TOF‐MS/MS detection technique. Level of quantification (LOQ) was 50 μg mL–1. The decline of the plasma concentration‐time curve of the HBOC was described by a 2‐compartment model (C1 and C2). The median distribution alpha (t1/2k1,0) and elimination beta (t1/2k2,0) half‐lives were 1.3 and 12.0 hours, respectively. The bHb molecules in OXY are not of uniform size and vary substantially in molecular weight (MW). Of the OXY molecules 53% were eliminated in C1, which represented the smaller MW molecules and 47% in C2, which represented the larger MW bHb. The maximal 0‐time plasma concentration was 662.0 μg/mL and declined to 97.1 μg mL–1 at 24 h. The area below the plasma concentration‐time curve was 5143 μg h–1 mL–1. The volumes of C1 and C2 were 86.9 and 63.9 mL kg–1, respectively. Oxyglobin was not detected in urine. This study shows the detection and quantification in equine plasma of a HBOC following IV infusion and demonstrates the short half‐life of about 50% of infused bHb molecules.  相似文献   
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