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41.
Summary Biomechanical models of the cervical spine require knowledge of the position, size and orientation of the individual muscles that act on the cervical spine. We have developed a technique to stereometrically measure anatomical specimens. The apparatus is composed of three graduated metallic rods, which slide along a fixed support. This method is accurate to map the anatomy of individual muscles and provides quantitative data on their lines of action. Results are obtained from one specimen. The computer processing of the collected data allows formulation of a three-dimensional model of the neck muscles in man.
Méthode d'étude anatomique quantitative des muscles de la nuqueEtude préliminaire
Résumé Pour élaborer un modèle biomécanique de la colonne cervicale, il faut connaître la position, la taille et l'orientation des différents muscles du cou. Nous avons mis au point une méthode de mesure stéréométrique sur des sujets anatomiques. L'appareil est composé de 3 axes métalliques gradués qui coulissent sur un support fixe. Cette technique permet une étude anatomique précise de chacun des muscles de la nuque, fournissant des données quantitatives sur les différents faisceaux ou lignes d'action. Les résultats sont obtenus sur un sujet. Leur traitement informatique permettra l'élaboration d'un modèle mathématique tridimensionnel des muscles du cou chez l'homme.
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The recombination events of the γ and β T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR αβ PTCLs, 22/23 cases showed a γ-gene rearrangement while only 18/23 showed a concomitant β-gene rearrangement. The germline configuration of the β locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three γδ PTCLs rearranged both γ and β genes. TCR silent PTCLs showed three different patterns of γ- and β-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged γ and a germline β locus; and five cases had the two loci rearranged. Regarding the variable genes in the γ-rearranged alleles, members of the VγI subgroup were the most frequently presented (39/50), followed by VγII, VγIII, and VγIV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the γ locus is more frequently rearranged whatever the TCR expression. The γ-locus analysis provides a better diagnostic yield than the β locus in the study of PTCL clonality.  相似文献   
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The membrane phenotype of human T cell colony progenitors and that of their clonal progeny was studied for expression of the T4 and T8 determinants. Using clonal culture conditions, the colonies were grown in semi-solid agar medium from peripheral blood cells. Clonality was assessed using the glucose-6-phosphate-dehydrogenase isoenzyme marker. Combination of this marker with the culture of sorted cell fractions allowed us to ascribe the colony progenitors to a subset of OKT4+ lymphocytes. The progeny consisted of the mixture of single OKT4+, single OKT8+ and double OKT4+8+ cells, as determined by double staining. Double staining was performed on mass-harvested colony cells and on individual colonies expanded in liquid culture with fresh interleukin 2. Expression of the OKT8 positivity on colony cells deriving from OKT4+ progenitors required an interaction with radioresistant OKT8+ cells that were co-cultured with these progenitors. Furthermore, the functional capacities of the cell progeny were assayed on the pokeweed mitogen-driven immunoglobulin production by B cells. It was found that OKT4+ colony cells were helper whereas OKT8+ colony cells were suppressor cells. It is concluded that a subset of OKT4+ peripheral blood T lymphocytes can generate colonies containing both helper OKT4+ cells and suppressor OKT8+ cells.  相似文献   
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Summary To study the antenatal differentiation of the human intervertebral disc, the columns of forty eight embryos and fetuses were examined histologically. The primitive disc is composed of two structures: the notochord which shows a progressive expansion into the disc, and the fibrocartilaginous perinotochordal disc. No histological sign of interaction between notochordal and perinotochordal cells, which may explain the notochordal expansion into the discs, was seen. On the other hand, the notochordal intervention in the cartilaginous differentiation of the inner zone is probable.
Différenciation anténatale du disque intervertébral humain
Résumé Cette étude de la différenciation anténatale du disque intervertébral humain repose sur l'examen de coupes histologiques de quarante huit colonnes vertébrales d'embryons et de foetus. Le disque primitif est composé de deux structures : la notochorde, qui présente une expansion progressive de son diamètre au sein du disque, et le disque périnotochordal, d'abord mésenchymateux puis fibrocartilagineux. Il n'a pas été mis en évidence de signe histologique témoignant d'une interaction entre les cellules notochordales et les cellules périnotochordales qui puisse expliquer l'expansion de la notochorde au sein des disques. Le rôle de la notochorde dans la différenciation cartilagineuse de la zone centrale est par contre probable.
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47.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。  相似文献   
48.
Patients with total hip arthroplasty were screened for the presence of proinflammatory cytokines in the systemic circulation. Only increased levels of interleukin-6 were detected in patients having had total hip arthroplasty more than 10 years ago. These increased levels of interleukin-6 were associated with a decrease in bone mineral density associated with polyethylene wear and with radiologic osteolysis in some patients. These abnormalities were not found in control subjects without total hip arthroplasty or in patients who had a prosthesis in place for less than 6 years. The elevation in interleukin-6 levels found in patients with the oldest prostheses could constitute a marker for periprosthetic osteolysis.  相似文献   
49.
We previously reported that polyinosinic-polycytidylic acid, a potent interferon inducer, inhibits the growth of B16 malignant melanoma in the C57BL/6 mouse. Two experiments were done to evaluate the effectiveness of interferon in tumor inhibition in vivo. In the first, mice were implanted with melanoma and divided into four groups, according to treatment: interferon preparation; interferon control preparation ("breakthrough fraction"); phosphate-buffered saline control; and murine serum albumin control. Daily, each mouse was given i.p. injections of 200,000 NIH reference units (hereafter called units) of interferon or of one of the control substances. The second experiment was similar to the first, except that bovine serum albumin was an additional control. In both experiments, the average tumor volume in interferon-treated mice was statistically significantly smaller than that of each control group. Mouse interferon preparations also inhibited the multiplication of B16 malignant melanoma cells in culture. This inhibition was statistically significant from interferon levels as low as 5 to as high as 5000 units/ml. The degree of inhibition markedly increased from 5 up to 500 units, the inhibition reaching its maximum at this concentration. The inhibitory effect of interferon was abrogated by anti-murine interferon serum produced in a rabbit. These findings suggest that the in vivo inhibition of the growth of B16 melanoma demonstrated with polyinosinicpolycytidylic acid and with exogenous interferon probably results, at least in part, from a direct effect of interferon on the tumor cells themselves.  相似文献   
50.
In two headache questionnaire surveys we inquired about the occurrence of headache in the mothers, fathers, siblings and children of the respondents. In total, 633 people completed valid questionnaires, 260 in the first survey and 373 in the second. The hypothesis was that familial headache occurrence would be positively associated with headache frequency. In each survey, the regression of headache frequency on the number of parents having headache was highly significant. Neither sex nor the sibling and children variables were significant predictors. In the cross-tabulations of the parental occurrence of headache with headache frequency we saw a clear "break-point" between the "no headache" and the headache frequency categories studied. For the final analyses the dichotomy "headache/no headache" was related in fourfold tables to headache occurrence in the father and the mother separately, and to the number of headache parents. The positive associations were not simply due to the large number of migraine cases since they remained after removing the migraineurs.  相似文献   
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