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71.
72.
Sheep are an important biological model in such diverse areas as immunology and reproductive biology. The limitation of sheep as an experimental model is the absence of reliable cell lines. To establish cell lines that express functional sheep membrane molecules, we produced a sheep x mouse heterohybridoma by fusion of sheep efferent lymph T cells with the murine myeloma cell line NS1. A cloned heterohybridoma fusion partner was selected by treatment with 8-azaguanine. The resulting cell line HL1/385 was selected for hypoxanthine/aminopterin/thymidine (HAT) sensitivity and growth efficiency. The HL1/385 cell line was used as a back-fusion partner into lectin-stimulated efferent T lymphocytes. The back-fusion approach produced more than 50 heterohybrid cell lines with high growth efficiency. The expression of physiological levels of the sheep beta-1 integrin cell surface molecule on the HT4/6 cell line was stable for months in culture. These results suggest that somatic heterohybrids may provide a reliable source of cell lines for sheep studies in vitro. 相似文献
73.
Choroid plexus carcinoma was diagnosed in a 5-year-old female mixed breed dog which was euthanized due to progressive neurologic disease. Diagnosis of the tumour was based on gross and light microscopic findings following a complete necropsy. The chemical staining patterns in the case are compared with human choroid plexus tumours. The criteria for the distinction between benign and malignant variants of choroid plexus tumours are discussed. 相似文献
74.
The authors examine the DSM-III distinction between schizoid and avoidant personality disorders. This distinction is based on Millon's biosocial learning theory and his interpretation of Kretschmer's personality types. The authors argue that this separation of a continuous distribution is historically misconceived and serves to obscure the significant features of schizoid personality. They examine Kretschmer's conceptualization of schizoid personality for the implications it carries for the development of a classification of personality disorder, suggesting that Kretschmer's approach implies a "polythetic" model of personality disorder that conceptualizes disorders as categories of dimensions. 相似文献
75.
In this experiment subjects were briefly presented with a vertically written word to either the left or right visual field. On half the critical trials the target word was irregular in its spelling-to-sound correspondence (e.g. PINT) and in the other half it was regular (e.g. LIME). With right visual field presentation substantially more regular than irregular words were reported correctly but with left visual field presentation no such effect was found. The data also showed the presence of far more "regularization" errors following right visual field presentation. The data are seen as consistent with the view that the right hemisphere is not capable of generating phonology. 相似文献
76.
BackgroundIn the context of the opioid epidemic, a limited but growing body of literature has found state medical marijuana laws (MMLs) to be associated with lower levels of opioid prescribing. However, robust evidence linking state MMLs with individual-level opioid-related outcomes is lacking, particularly among women. This finding is especially true for pregnant and parenting women, who have been disproportionately affected by the opioid crisis.MethodsUsing data drawn from the 2002–2014 National Survey on Drug Use and Heath, the study uses a difference-in-differences estimation strategy to compare opioid-related outcomes (opioid misuse initiation, opioid misuse in the past month and past year, and opioid use disorder) among all women, pregnant women, and parenting women in states with and without MMLs (before and after implementation). The study also investigates the impact of MMLs on marijuana use and marijuana use disorder.ResultsThe findings indicate that MMLs were not associated with opioid misuse, opioid misuse initiation, or opioid use disorder among all women, pregnant women, and parenting women. These laws were, however, positively correlated with marijuana use and marijuana use disorder among all women and women with children. In addition, MMLs were associated with an increase in the frequency of opioid misuse for pregnant women and a decrease in the frequency of opioid misuse for parenting women.ConclusionsThis finding suggests that, although medical marijuana may be viewed by some as a substitute for opioid analgesics, MMLs may not be an effective policy tool to tackle the opioid epidemic among women, especially pregnant and parenting women. 相似文献
77.
Custom 3D printed total talus implants have been used successfully as a functional alternative to arthrodesis or amputation in cases of severe talar destruction or loss. However, the ideal material and construct still remains to be elucidated. Current models have been made from aluminum ceramic, cobalt chrome, stainless steel, titanium, or metal combinations. The implants may be constrained (subtalar arthrodesis) or unconstrained (press fit within mortise). They may also be combined with a tibial prosthesis or used in isolation. The majority of currently published case studies examine unconstrained and isolated implants. This case study presents satisfactory 1-y outcomes in 3 cobalt chrome constrained total talar implants used in combination with a tibial prosthesis, and a literature review of total talus replacements. 相似文献
78.
79.
Thierry Tiendrebeogo Eugne Messou Shino Arikawa Didier K Ekouevi Aristophane Tanon Vivian Kwaghe Eric Balestre Marcel Djimon Zannou Armel Poda Franois Dabis Antoine Jaquet Albert Minga Renaud Becquet IeDEA West Africa Collaboration 《Journal of the International AIDS Society》2021,24(5)
IntroductionSex differences have already been reported in sub‐Saharan Africa for attrition and immunological response after antiretroviral therapy (ART) initiation, but follow‐up was usually limited to the first two to three years after ART initiation. We evaluated sex differences on the same outcomes in the 10 years following ART initiation in West African adults.MethodsWe used cohort data of patients included in the IeDEA West Africa collaboration, who initiated ART between 2002 and 2014. We modelled no‐follow‐up and 10‐year attrition risks, and immunological response by sex using logistic regression analysis, survival analysis with random effect and linear mixed models respectively.ResultsA total of 71,283 patients (65.8% women) contributed to 310,007 person‐years of follow‐up in 16 clinics in eight West African countries. The cumulative attrition incidence at 10‐year after ART initiation reached 75% and 68% for men and women respectively. Being male was associated with an increased risk of no follow‐up after starting ART (5.1% vs. 4.0%, adjusted Odds Ratio: 1.25 [95% CI: 1.15 to 1.35]) and of 10‐year attrition throughout the 10‐year period following ART initiation: adjusted Hazard Ratios were 1.22 [95% CI: 1.17 to 1.27], 1.08 [95% CI: 1.04 to 1.12] and 1.04 [95% CI: 1.01 to 1.08] during year 1, years 2 to 4 and 5 to 10 respectively. A better immunological response was achieved by women than men: monthly CD4 gain was 30.2 and 28.3 cells/mL in the first four months and 2.6 and 1.9 cells/μL thereafter. Ultimately, women reached the average threshold of 500 CD4 cells/μL in their sixth year of follow‐up, whereas men failed to reach it even at the end of the 10‐year follow‐up period. The proportion of patients reaching the threshold was much higher in women than in men after 10 years since ART initiation (65% vs. 44%).ConclusionsIn West Africa, attrition is unacceptably high in both sexes. Men are more vulnerable than women on both attrition and immunological response to ART in the 10 years following ART initiation. Innovative tracing strategies that are sex‐adapted are needed for patients in care to monitor attrition, detect early high‐risk groups so that they can stay in care with a durably controlled infection. 相似文献
80.
慢性肺源性心脏病人血液触变特性 总被引:1,自引:0,他引:1
本文用Low Shear 30流变测定仪,测定了55例肺心病患者全血触变特性的变化,分析了这些变化与肺心病发生和发展的关系。结果表明:肺心病患者血液的触变特性发生了异常改变。HCT、τ_o、η_s、μ、(η_s-μ)、A、ARC均升高,并随病情加重而逐渐明显。其原因主要在于肺心病缺氧所致的继发性红细胞增多及血液氧分压降低,和二氧化碳分压升高所致的红细胞变形性降低。血液触交特性的改变又使血液循环外周阻力增大,右心负荷增加,从而进一步加重了病情的发展。 相似文献