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21.
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   
22.
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   
23.
樟树茎段组培快繁   总被引:1,自引:0,他引:1       下载免费PDF全文
以当年生樟树Cinnamomum camphora带芽茎段为外植体,研究6-苄基腺膘呤(6-BA)和萘乙酸(NAA)在初代培养和继代培养过程中对樟树茎段腋芽及丛生芽诱导增殖的影响。结果表明:最适腋芽诱导培养基为MS(Murashige and Skoog)+1.00 mgL-1 6-BA+(0.01~0.10 mgL-1) NAA。继代培养时采用正交试验设计进行培养基筛选,经极差分析和方差分析得知丛生芽发生率较高的培养基为MS+1.00 mgL-1 6-BA + 0.10 mgL-1 NAA,而丛生芽增殖最佳培养基为MS+(0.50~1.00) mgL-1 6-BA。将无菌苗转入最适生根培养基1/2MS+1.50 mgL-1 NAA,生根率可达90%;生根的无菌苗移栽至m(蛭石)∶m(泥炭)为1 ∶ 1的混合基质中,经过15~20 d练苗,95%以上无菌苗均能成活。这一结果为樟树优良品种的工业化育苗奠定了技术基础。图2表5参13  相似文献   
24.
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   
25.
Clinical isolates (n = 63) of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes) showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E) accounting for 10/63 (15.9%) of the isolates. ERIC2 RAPD PCR proved to be a highly discriminatory molecular typing tool of P. aeruginosa in isolates recovered from horses. With the adoption of several controls to aid reproducibility, this technique may be useful as an alternative to PFGE, particularly in epidemiological investigations of outbreaks where speed may be a significant parameter. This is the first report of clonal heterogeneity amongst P. aeruginosa from horses and demonstrated that ERIC RAPD PCR is a rapid method for the examination of this species in horses, which may be useful in outbreak analysis.  相似文献   
26.
Previously, three distinct populations of putative primordial germ cells (PGCs), namely gonocytes, intermediate cells and pre‐spermatogonia, have been described in the human foetal testis. According to our knowledge, these PGCs have not been studied in any other species. The aim of our study was to identify similar PGC populations in canine embryos. First, we develop a protocol for canine embryo isolation. Following our protocol, 15 canine embryos at 21–25 days of pregnancy were isolated by ovaryhysterectomy surgery. Our data indicate that dramatic changes occur in canine embryo development and PGCs specification between 21 to 25 days of gestation. At that moment, only two PGC populations with distinct morphology can be identified by histological analyses. Cell population 1 presented round nuclei with prominent nucleolus and a high nuclear to cytoplasm ratio, showing gonocyte morphology. Cell population 2 was often localized at the periphery of the testicular cords and presented typical features of PGC. Both germ cell populations were positively immunostained with anti‐human OCT‐4 antibody. However, at day 25, all cells of population 1 reacted positively with OCT‐4, whereas in population 2, fewer cells were positive for this marker. These two PGCs populations present morphological features similar to gonocytes and intermediate cells from human foetal testis. It is expected that a population of pre‐spermatogonia would be observed at later stages of canine foetus development. We also showed that anti‐human OCT‐4 antibody can be useful to identify canine PGC in vivo.  相似文献   
27.
As part of an ongoing research program to synthesize novel pillared layered materials, nickel and cobalt hydroxyacetates were inserted between the layers of amine intercalates of alpha-zirconium phosphate. The structure of the resultant nickel composite, derived from x-ray powder data, was found to consist of a three-tiered layer of nickel atoms bridged by hydroxo and acetato groups. Heating to 420 degrees C converted the hydroxyacetate layers to oxide and imparted ordered magnetic domains to the composite. The phosphate layers appear to act as a template directing the growth of the inserted layers in this class of composite materials.  相似文献   
28.
关于内蒙古大兴安岭林区实施森林抚育补贴项目的探讨   总被引:2,自引:0,他引:2  
文章通过对内蒙古大兴安岭林区实施森林抚育补贴项目的背景、必要性的分析,论述了森林抚育是促进林区生态、经济和社会协调发展的有力措施。  相似文献   
29.
30.
Many researches describe the embryonic developmental features in domestic animals; however, in farm animals, they are scarce. Most farm animal studies are related to assisted reproduction and embryos transfer techniques. But, morphological features and size measure to estimate the age gestation are rarely reported in literature. Thus, in this study, we described the developmental changes in the bubaline (Bubalus bubali) concepts from 21 to 60 days of gestation. Our results revealed that buffalo embryos similar morphological characteristics similar to other mammalian species. Also, similarities between bovine and bubaline persist; except on foetal stages when buffalos have a faster development than bovine. Therefore, buffalo's gestation period exhibits some varieties and accurate embryo age is more difficult. Yet, when we use a combination of the crown–rump, macroscopic analysis and alizarin red, it is possible to describe better the whole embryogenesis stages of the buffalo and which can contribute for future reproduction researches and applications in veterinary practice.  相似文献   
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