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991.
Robson C. Gutierre Mizue I. Egami Marta M. Antoniazzi Carlos Jared 《Comparative clinical pathology》2008,17(4):221-228
The caecilians (Amphibia, Gymnophiona) constitute one of the least known groups of terrestrial vertebrates because most species
live underground in quite inaccessible environments. Siphonops annulatus is an exclusively fossorial species and is the most extensively distributed caecilian in South America. Little is known of
this order concerning circulating granulocytes, including their morphological and cytochemical structure and ultrastructure.
This paper is part of a project covering the study of granulocytes in representative species of the order Amphibia. Blood
extensions were carried out and submitted to Leishman, Toluidine Blue, Periodic acid Schiff, Sirius Red and hydrogen o-toluidine peroxide methods. Part of the samples was prepared for conventional transmission electron microscopy. Among granular
leukocytes, mature and immature neutrophils and eosinophils were identified, plus basophils. The most frequent granulocyte
encountered in S. annulatus peripheral blood is the neutrophil. This is a cell with a hyper-segmented nucleus and with a very clear cytoplasm when compared
to the eosinophil, which presents large cytoplasmic acidophilic granules. On the other hand, the basophils present basophilic
and metachromatic granules. Glycogen was detected in the cytoplasm of the neutrophils and eosinophils, while basic protein
rich in amino acids was observed in the eosinophil’s granules. Myeloperoxidase activity was detected in the cytoplasm of the
neutrophils and eosinophils. Neutrophils were ultrastructurally detected with three types of small granules: eosinophils with
large and small spherical granules and basophils with large spherical granules with lamellate structures. 相似文献
992.
David P. Bazett-Jones Ren Li Eden Fussner Rosa Nisman Hesam Dehghani 《Chromosome research》2008,16(3):397-412
Electron microscopy has been the ‘gold standard’ of spatial resolution for studying the structure of the cell nucleus. Electron
spectroscopic imaging (ESI) offers advantages over conventional transmission electron microscopy by eliminating the need for
heavy-atom contrast agents. ESI also provides mass-dependent and element-specific information at high resolution, permitting
the distinguishing of structures that are primarily composed of protein, DNA, or RNA. The technique can be applied to understand
the structural consequences of epigenetic modifications, such as modified histones, on chromatin fiber morphology. ESI can
also be applied to elucidate the multifunctional behavior of subnuclear ‘organelles’ such as the nucleolus and promyelocytic
leukemia nuclear bodies.
The authors dedicate this paper to the memory of Ying Ren (1961–2007). We all benefited from knowing her. Our research advanced
through the technical creativity she provided. 相似文献
993.
994.
Single sperm typing demonstrates that reduced recombination is associated with the production of aneuploid 24,XY human sperm 总被引:13,自引:0,他引:13
Shi Q Spriggs E Field LL Ko E Barclay L Martin RH 《American journal of medical genetics》2001,99(1):34-38
To account for the increased proportion of paternal nondisjunction in 47,XXY males as compared to other trisomies, it has been suggested that the XY bivalent, with its reduced region of homology, is particularly susceptible to nondisjunction. Molecular studies of liveborn Klinefelter syndrome (47,XXY) individuals have reported an association between the absence of recombination in the pseudoautosomal region and nondisjunction of the XY bivalent. In this study we examined single sperm from a normal 46,XY male to determine if there is any alteration in the recombination frequency of aneuploid disomic 24,XY sperm compared to unisomic sperm (23,X or Y). Two DNA markers STS/STS pseudogene and DXYS15 were typed in sperm from a heterozygous man to determine if recombination had occurred in the pseudoautosomal region. Individual unisomic sperm (23,X or Y) were isolated using a FACStar(Plus) flow cytometer into PCR tubes. To identify disomic 24,XY sperm, 3-colour FISH analysis was performed with probes for chromosomes X,Y and 1. The 24,XY cells were identified using fluorescence microscopy, each disomic sperm was scraped off the slide using a glass needle attached to a micromanipulator and then put into a PCR tube. Hemi-nested PCR analysis of the two markers was performed to determine the frequency of recombination. A total of 329 unisomic sperm and 150 disomic sperm have been typed. The frequency of recombination between the two DNA markers was 38.3% for the unisomic sperm, similar to frequencies previously reported. The 24,XY disomic sperm had an estimated recombination frequency of 25.3%, however, a highly significant decrease compared to the unisomic 23,X or 23,Y sperm (chi(2) = 10.7, P = 0.001). This direct analysis of human sperm indicates that lack of recombination in the pseudoautosomal region is a significant cause of XY nondisjunction and thus Klinefelter syndrome. Copyright Wiley-Liss. Inc. 相似文献
995.
Y D Shi 《中华神经精神科杂志》1990,23(6):348-50, 384
In this article, 163 cases of hypertension patients and 117 cases of stroke patients with acute period including 43 cases of hemorrhagic strokes and 74 cases of ischemic strokes were analyzed between average arterial blood pressure and blood viscosity. The curves of relation of blood pressure versus blood viscosity in the hypertension patients' group showed "M" shape. The hemorrhagic stroke patients were located by up-side of the "M" shape curve and the ischemic stroke patients were situated by the down-side of the "M" shape curve. 相似文献
996.
This paper reports 25 kinds of polyclonal or monoclonal antibodies by ABC immunohistochemical technique used for 253 cell smears by fine-needle aspiration. The results were,1. Immunohistochemical diagnosis were classified into 136 metastatic cancers ( K12 EMA CEA LCA-),92 lymphomas (LCA k12- EMA- CEA-), 4 mesenchymal tumors (Vimentin ), 3 melanomas (S-100 NSE ). 15 reactive proliferations (k λ4 CD CD8 ) and 3 unspecified.2. The origin of 70 metastatic cancers were classified into 36 lung (HLC3-AB ), 4 gastrointestinal tract (MG7 ), 8 thyroid (TGB ), 1 prostate (PSA ), 3 liver (AFP ) and 14 unknown. 3. Immunologic phenotype of 87 lymphomas wereclassified into 66 cases of B-cell, 4 T-cell, 3 hsitocyte, 7 Hodgkin' s diseases and 7 unclear. The above results suggest that immunohistochemlcal method may be used as a new method of diagnosing and differentiating epithelial and non-epithelial tumors, detecting primary focus of metastatic cncer, differentiating between reactive proliferation adn lymphome a 相似文献
997.
研究国内来源于地榆属8个不同种、变种与变型的地榆及2种混淆品的生药性状、组织构造及其粉末的鉴别特征,并分别列出生药性状、组织构造及粉末特征的检索表。 相似文献
998.
The reliability of a five-item Katz's Activities of Daily Living (ADL) scale collected by self-report telephone interview is presented. A random sample of 6,472 South Carolina residents over 55 years of age selected from a statewide population is used. Factor structure, Guttman properties, internal consistency reliability, Mokken's index of test homogeneity, and Spearman's coefficient of rank-order correlation are used to show that ADL data gathered by telephone interview are reliable. Because telephone interviewing methods are faster, cheaper, and safer they are recommended as a viable way for researchers, policymakers, and practitioners to gather ADL information. 相似文献
999.
1000.
rIL—2、TNF—α、IFN—γ对抗CD3—抗胶质瘤双特异性抗体的协同细胞毒作用 总被引:3,自引:1,他引:2
目的:观察细胞因子rIL-2、TNF-α、IFN-γ对抗CD3-抗胶质瘤双特异性抗体(双抗)的协同作用,进一步提高双抗对人脑胶质瘤的治疗作用。方法:以人脑胶质瘤细胞株SHG-44为靶细胞,健康人或胶质瘤患的外周血单个核细胞(PBMC)为效应细胞,以18h ^3H-TdR掺入释放法测定细胞毒活性,采用单比实验和联合作用等对比分析方法,分析各细胞因子(rIL-2、TNF-α、IFN-γ)对双抗诱导的细胞毒性作用的影响。结果:rIL-2、TNF-α、IFN-γ均可协同提高双抗对人脑胶质瘤的细胞毒作用(P<0.05)。来源于恶性胶质瘤患的效应细胞活性较正常人低,rIL-2与双抗可协同增强其活性。结论:细胞因子rIL-2、TNF-α、IFN-γ可协同提高双抗对效应细胞的活化,充分激活效应细胞,增强抗肿瘤免疫能力。 相似文献