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81.
Expression of the human T cell receptor V beta repertoire.   总被引:5,自引:0,他引:5  
We have used a sensitive assay, based on amplification of cDNA by the polymerase chain reaction, to determine in a variety of human tissues the relative levels of expression of the genes coding for each of the twenty families of human TcR V beta. We have determined the diversity of the expressed TcR V beta repertoire early in the development of the immune system. We have shown that the full TcR V beta repertoire is expressed early into the second trimester; the expressed repertoire is as diverse at this point, in both fetal thymus and spleen, as it is in mature thymus and peripheral blood lymphocytes. In addition the relative expression in the fetal thymus of each V beta gene is conserved to a large extent in the fetal spleen.  相似文献   
82.
In this study we investigate the expression pattern of mucin genes in the human testis and evaluate the relationship between the expression of mucin genes and impaired spermatogenesis in the human testis. Thirty human testis tissues were collected from patients undergoing diagnostic testicular biopsy to investigate the cause of infertility. One part of the tissue underwent histological observation, and the other part of the tissue was subjected to semiquantitative RT-PCR of mucin genes, that is, mucin1, 2, 3, 4, and 9. The relative amount of mucin mRNAs was calculated by densitometry using glyceraldehydes-3-phosphate dehydrogenase (GAPDH) as an internal control. The samples were histologically diagnosed as either obstructive azoospermia with normal spermatogenesis (n = 13) or non-obstructive azoospermia with impaired spermatogenesis (n = 17). In the human testis with normal spermatogenesis, mRNA expression of mucin1, 9, 13 and GAPDH were found, but RT-PCR products of mucin 2, 3 and 4 were not detected. In the testis with impaired spermatogenesis, however, RT-PCR product of mucin1 was not found. There was no difference in the other mucin mRNA expression patterns between the testis with either normal or impaired spermatogenesis. To our knowledge, this study is the first that has detected the mRNA of mucin9 and 13 in human testis. This study also shows that mucin1 expression might be closely related to spermatogenesis. Our findings should be substantiated by more direct evidence, such as mucin protein expression and localization.  相似文献   
83.
Jeune syndrome (JS) and short-rib polydactyly syndrome type III (SRP type III) are autosomal recessive disorders characterized by short ribs and polydactyly. They are distinguished from each other by the more severe radiological and histological bone findings as well as the occurrence of facial anomalies, ambiguous genitalia, and occasionally, cloacal abnormalities in SRP type III. We present a family in which two children have mild JS and one has SRP type III as evidence that JS and SRP type III are variants of the same disorder. The intrafamilial variability may reflect the effects of modifying loci on gene expression.  相似文献   
84.
Kim KM  Kim HW  Kim JO  Baek KM  Kim JG  Kang CY 《Immunology》2002,107(4):472-479
4-1BB(CD137) is a member of the tumour necrosis factor receptor superfamily and is expressed on activated T cells, monocytes and natural killer (NK) cells. The interaction of 4-1BB and 4-1BB ligand provides a costimulatory signal leading to T-cell activation. The expression of 4-1BB has been known to be activation dependent. Interestingly, we found that expression of 4-1BB increased in human peripheral blood mononuclear cells after exposure to mitomycin C. Thus, we tested whether the treatment with other DNA-damaging agents, such as doxorubicin, bleomycin, and gamma-irradiation, could induce 4-1BB expression. The data indicated that 4-1BB expression increased dose-dependently by these agents reaching maximum at 2-3 days after the exposure. We found that the major 4-1BB-expressing population was CD3+ T cells, although a moderate number of CD14+ cells and a few NKB1+ cells also expressed 4-1BB. The levels of 4-1BB expression induced by anticancer drugs, were relatively lower than that induced by CD3 ligation. Interestingly, at subcytotoxic concentrations, doxorubicin and bleomycin considerably enhanced 4-1BB expression induced by CD3 ligation in CEM cells. The ligation of the damage-induced 4-1BB by monoclonal antibody enhanced the viability and proliferating capacity of the cells. In conclusion, the expression of 4-1BB might be one of the cellular responses of the immune cells against various genotoxic stresses.  相似文献   
85.
BACKGROUND: Type-specific persistence of human papillomavirus (HPV) infection can cause invasive cervical cancer. OBJECTIVES: To evaluate the efficacy of HPV detection and typing with a general polymerase chain reaction (PCR)-based genotyping array and to compare it with a type-specific PCR assay. STUDY DESIGN: Four hundred and thirty-three cervical samples were tested with a modified MY11/GP6+ PCR-based reverse-blot assay (EasyChip HPV Blot; King Car, Taiwan [hereafter HPV Blot]) and with 20 genotypes of L1-type-specific PCR (HPV-6, -11, -16, -18, -31, -33, -35, -39, -45, -51, -52, -53, -56, -58, -59, -62, -66, -68, -70, and -71 [CP8061]). RESULTS: The concordance of the two tests in determining HPV positivity was 96.8% (419/433), with a Cohen's kappa=0.93 (95% CI: 0.90-0.97) and McNemar's test of P=1.0, which indicates excellent agreement. The overall concordance of the two tests in the identification of type-specific HPV was 91.0% (394/433). Sensitivity (90-100%), specificity (99.2-100%), and accuracy (98.6-100%) rates of HPV Blot against the gold standard were satisfactory for HPV-16, -18, -58, -33, -52, -39, -45, -31, -51, -70 while HPV-71 (63.6%) had suboptimal sensitivity. Though the kappa values between the two tests for many individual genotypes could not be reliably calculated because of low positivity, the kappa values for HPV-16, -52, and -58 were excellent (0.93, 0.96, and 0.95, respectively). CONCLUSION: The modified MY11/GP6+ PCR-based HPV Blot assay is accurate and sensitive for detection and genotyping of HPV in cervical swab samples.  相似文献   
86.
L Ho  A Cohen 《Virology》1975,67(2):588-590
An anaerobic plating technique for bacteriophage is described. This technique results in larger plaque sizes for at least nine of the bacteriophages that grow on Salmonella and Escherichia coli. The advantage of this plating technique for the selection of nonsense mutants in certain phage strains is discussed.  相似文献   
87.
The anatomy of the cardiac conduction system in normal and malformed hearts reconstructed from histological serial sections is reviewed. The sinus node and its arterial supply are located in the right superior cavoatrial junction except in hearts with left-sided juxtaposition of the atrial appendages, mirror-image, and isomeric arrangements of the atria. In the presence of normally positioned atrial and ventricular septal structures, the triangle of Koch is a useful guide to the location of the atrioventricular node and the penetrating bundle. In hearts with isolated ventricular septal defects, it is necessary to distinguish between a perimembranous defect and a muscular inlet defect. The conduction axis runs in the area of fibrous continuity at the posteroinferior edge of a perimembranous defect but in the anterosuperior rim of a muscular inlet defect. In most hearts with tetralogy of Fallot, the danger area is the region of aortic-mitral-tricuspid fibrous continuity where the axis penetrates. In hearts with atrioventricular septal defects, the lack of contiguity between atrial and ventricular septum results in a posterior displacement of the nodal triangle and coronary sinus and an elongation of the nonbranching bundle. Hearts with abnormally located atrioventricular nodes and conduction axes are mainly those with atrioventricular discordance, ambiguous atrioventricular connection in presence of left-hand pattern ventricular topology, hearts with univentricular atrioventricular connection to a morphologically left or indeterminate ventricle, and hearts with a straddling tricuspid valve. The location of the atrioventricular node is governed by the orientation of the ventricular septum and by the pattern of ventricular topology.
Resumen Se revisa la anatomía del sistema de conducción cardiaca en los corazones normales y con malformaciones a la luz de la reconstrucción a partir de cortes histológicos seriados. El nódulo sinusal y su irrigación arterial está ubicado en la unión cavoatrial derecha, excepto en corazones con yuxtaposición izquierda de las auriculillas o con alteraciones en imagen en espejo e isoméricas de las aurículas. En presencia de estructuras septales atriales y ventriculares normalmente ubicadas, el tríangulo de Koch es una guía útil para la localización del nódulo atrioventricular y la penetración del haz. En corazones con defectos septales ventriculares aislados es necesario distinguir entre un defecto perimembranoso y un defecto del tracto muscular de entrada. El haz de conducción avanza en el área de continuidad fibrosa sobre el borde posteroinferior de un defecto perimembranoso, en el filo anterosuperior de un defecto del tracto muscular de entrada. En la mayoría de los corazones con tetralogía de Fallot el área de peligro se encuentra en la región del trígono fibroso aórticomitral y tricuspídeo sobre el cual penetra el haz de conducción. En corazones con defectos septales atrioventriculares la falta de continuidad entre el septo atrial y el ventrícular resulta en un desplazamiento posterior del triángulo de Koch y del seno coronario y en una elongación del haz no ramificado. Corazones con nódulos atrioventriculares y haces de conducción anormalmente ubicados son principalmente aquellos con discordancia atrioventricular, con conexión atrioventricular ambigua en presencia de un patrón izquierdo de arquitectura ventricular, corazones con conexión atrioventricular univentricular a un ventrículo morfológicamente izquierdo o indeterminado y corazones con válvula tricuspídea cabalgante. La ubicación del nódulo atrioventricular está determinada por la orientación del septo ventricular y por el patrón de la arquitectura ventricular.

Résumé L'anatomie du système de conduction du coeur normal et du coeur siège de malformations reconstituée à partir de coupes sériées histologiques est exposée. Le sinus nodal et sa vascularisation sont situés au niveau de la partie supérieure de la jonction auriculo-ventriculaire droite sauf dans certains cas: coeur avec juxtaposition des auricules du côté gauche, image en miroir et dispositions isomères des oreillettes. Lorsque les cloisons auriculaire et ventriculaire occupent une situation normale, le triangle de Koch constitue un repère utile pour localiser le noyau auriculo-ventriculaire et le faisceau de His. En cas de défects septaux ventriculaires isolés, il est nécessaire de distinguer les défects périmembraneux et les défects musculaires. L'axe nerveux conducteur chemine dans la zone de continuité fibreuse au bord postéroinférieur du défect périmembraneux mais il chemine au bord antéro-supérieur du défect musculaire. En cas de tétralogie de Fallot, le danger se situe souvent au niveau de la zone fibreuse de continuité aortique-mitrale-tricuspide où pénètre l'axe conducteur. En cas de coeur porteur d'un défect septal auriculo-ventriculaire, le défaut de continuité entre la cloison ventriculaire et la cloison auriculaire entraîne le déplacement postérieur du triangle nodal et du sinus coronaire ainsi que l'élongation du faisceau. Les coeurs qui présentent une anomalie du siège des noyaux auriculo-ventriculaires et des nerfs conducteurs sont principalement ceux qui sont le siège d'une anomalie auriculo-ventriculaire, d'une connexion auriculo-ventriculaire ambiguë en cas d'une disposition ventriculaire de type gauche, d'une connexion auriculo-ventriculaire univentriculaire avec une morphologie ventriculaire gauche ou indeterminée, d'une valve tricuspide en fourche. Le siège du noyau auriculo-ventriculaire est fonction de l'orientation du septum ventriculaire et de l'architecture ventriculaire.


Supported by the British Heart Foundation.  相似文献   
88.
The analgesic effect, of intracerebroventricular administration of morphine, ketocyclazocine, [D-ala2]-methionine enkephalinamide (DAM), [D-ala2-D-leu5]-enkephalin. (DADLE), leuenkephalin, metenkephalin, and -endorphin on acetic acid-induced abdominal writhing (AAW) was investigated in naive and morphine-tolerant mice. It was found that the relative potencies of a series of opioids are different in naive and morphine-tolerant groups. In naive animals, the order of potency (ED50, nmol) was -endorphin > morphine=DAM > DADLE > ketocyclazocine=leuenkephalin=metenkephalin. The morphine-tolerant animals were cross-tolerant to ketocyclazocine and to all the peptides studied; DAM and -endorphin exhibited the highest degree of tolerance. In morphine-tolerant animals, the order of potency was morphine=DADLE=-endorphin > DAM=ketocyclazocine =metenkephalin > leuenkephalin. The results indicate that endogenous opioid systems may be affected by tolerance development to morphine.  相似文献   
89.
Seventy-six hearts were studied having no direct communication between the right atrium and the ventricular mass. The different cardiac chamber combinations producing so-called "tricuspid atresia" were considered. The nature of the atrioventricular valve atresia, the morphology of the ventricular mass, the size and position of the interventricular communication, the ventriculoarterial connection, and the presence of subarterial outflow tract obstruction were all analyzed. The majority of cases were of the "classical" type, i.e., absent right atrioventricular connection with the left atrium connected to the left ventricle. In another group there was absence of the right atrioventricular connection but the left atrium drained into the morphologically right ventricle, which was left-sided. In a third group both atrial chambers connected with the ventricular mass but some structure, an imperforate valve or muscular partition, completely blocked the flow pathway through the right side of the heart. All the hearts described are candidates for the Fontan procedure with either an atrioventricular or an atriopulmonary conduit. The surgical options would not be affected by the observed variability at the atrioventricular junction but would be dictated by the feasibility of incorporating the subpulmonary ventricle within the pulmonary circulation.  相似文献   
90.
From 1976 to June 1982, 237 patients with clinical suspicion of hepatic malignant disease underwent guided percutaneous fine-needle aspiration biopsy of the liver. Of these, 12 were diagnosed cytologically as "hepatocellular carcinoma" and this diagnosis was confirmed in the follow-up of all cases. On the basis of the cytomorphologic features observed in the aspirates, the tumor was subclassified into three types; well differentiated, pleomorphic large cell; and poorly differentiated. The various cytologic appearances of different types of hepatocellular carcinoma are presented and illustrated. Cytomorphologically, these three types of hepatocellular carcinoma were distinctly different and their cytomorphologic features were also sufficiently distinctive from those of secondary hepatic cancer to be diagnostic. Guided percutaneous fine-needle aspiration biopsy of the liver appears to be a definitive minimally invasive means of establishing the diagnosis of hepatocellular carcinoma, and promises to be a valuable diagnostic procedure for potentially resectable localized hepatocellular carcinoma.  相似文献   
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