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991.
Donald G. Payan L. Joseph Wheat Zackarie Brahmi Stephen Ip W. Peter Hansen Robert A. Hoffman Kathleen Healey Robert H. Rubin 《Journal of clinical immunology》1984,4(2):98-107
Circulating T-lymphocyte subpopulations were enumerated in 65 patients with histoplasmosis and correlated with the different clinical manifestations of the disease. Acute pulmonary histoplasmosis, rheumatologic, disseminated, and chronic inflammatory manifestations of histoplasmosis were all associated with a significant elevation above normal of OKT8+ (suppressor-cytotoxic) lymphocytes and a significantly lower than normal OKT4+ (helper-inducer)-lymphocyte to OKT8+-lymphocyte ratio. In contrast, cavitary disease was associated with an increase in OKT4+ lymphocytes, a decrease in OKT8+ lymphocytes, and a higher than normal OKT4/OKT8 ratio. Clinical recovery was associated with normalization of these values. Functional activity determined by coculture techniques correlated closely with T-lymphocyte subset measurements. These distinct subset abnormalities may help monitor immunological aspects of disease activity. 相似文献
992.
Paris of hamsters were housed in large enclosures that contained separate male and female living areas and observed over the 4-day estrous cycle and after ovariectomy. Agonistic elements exhibited frequently by females included on-back, boxing, lateral posturing, and biting, whereas males engaged frequently in boxing and on-back patterns of behavior. Furthermore, on-back and boxing by females were significantly higher on estrus than on any other day of the estrous cycle. Agonistic acts performed after ovariectomy did not differ in occurrence from those shown by animals on diestrus and proestrus. Vaginal marking increased during diestrus and attained a peak 24 hr prior to sexual receptivity. Both vaginal marking and mating occurred more frequently in the female's than male's home area suggesting that vaginal marks on days preceding behavioral estrus serve to attract males to the nest of females. Males also organized their marking patterns by location as shown by more flank marking in their own than their partner's area, albeit the significance for this difference in location is not known. The results demonstrate that when heterosexual paris of hamsters are tested in large and partially familiar habitats, a wide range of behavior is exhibited and organized in a manner that is not observed in small and unfamiliar cages. 相似文献
993.
Richard S. Surwit Marilyn N. Bradner Cynthia H. Fenton Robert N. Pilon 《Psychophysiology》1978,15(4):320-323
The purpose of the present study was to assess the relationship between lateralization of body image and right versus left vasomotor activity. Fifteen right-handed female patients suffering from idiopathic Raynaud's disease demonstrated a relationship between the extent of right lateralization of body image and bilateral digital skin temperature during a controlled temperature stress test. In addition, subjects showing a reliable right side awareness demonstrated more unilateral vasospastic attacks in their right hand than their left hand white subjects showing no clear right lateralization by body image reported more left hand attacks than right hand attacks. These results were taken as consistent with previous work on the relationship between skin conductance and lateralization of body image. 相似文献
994.
Robert F. Phalen Hsu-Chi Yeh Otto G. Raabe David J. Velasquez 《Anatomical record (Hoboken, N.J. : 2007)》1973,175(2):255-517
A method for producing flexible silicone rubber casts of the airways of the lungs in-situ is described. Casts are made to correspond to lung volumes occurring during normal breathing. The lung is prepared for casting by replacing the air within with CO2 followed by filling with degassed physiological saline. The saline dissolves the CO2 gas within the airways allowing for a bubble-free finished cast. Casting compound is then slowly injected through the trachea. The saline diffuses out of the lung and passes out of the thorax through several small slits in the thoracic wall. After the injection is completed, the cast lung is allowed to cure in-situ before it is removed and the tissue digested away. Finished casts have an overall shape corresponding closely to the shape of the thorax. Casts produced by this in-situ method appear to have more realistic geometrical relationships than those produced from excised lungs. 相似文献
995.
Fas Ligand-dependent and -independent mechanisms of toxicity induced by T cell lymphomas in lymphoid organs and in the liver 总被引:15,自引:0,他引:15
Lombard C McKallip RJ Hylemon PB Nagarkatti PS Nagarkatti M 《Clinical immunology (Orlando, Fla.)》2003,109(2):144-153
In the current study, we investigated the effect of growth of FasL+ tumors in vivo on the functions of peripheral lymphoid organs and the liver. Injection of FasL+ LSA tumor cells into syngeneic C57BL/6 wild-type mice but not C57BL/6 lpr/lpr (Fas-deficient) mice caused apoptosis in splenocytes. Spleen cells expressing CD3, CD4, CD8, CD19, Mac-3, and CD44 were all susceptible to tumor-induced apoptosis. Also, activated T cells were more sensitive to apoptosis induced by LSA tumor cell lysate when compared to naïve T cells. In contrast, anti-Fas Abs (Jo2) induced apoptosis in only activated but not naïve T cells. When the LSA tumor-bearing mice were injected with a superantigen (SEA), these mice showed a significant decrease in the expansion of SEA-reactive Vβ3+ and Vβ11+ T cells. When injected into syngeneic mice, the FasL+ LSA tumor cells caused hepatotoxicity, as indicated by an increase in serum aspartate aminotransferase (AST) levels. Interestingly, Fas-deficient C57BL/6 lpr/lpr mice also showed significant AST levels in the serum following LSA tumor growth. Moreover, hepatocytes isolated from C57BL/6 wild-type and C57BL/6 lpr/lpr mice were equally susceptible to apoptosis induced by LSA tumor cell lysate in vitro. Using cDNA array, LSA tumor cells were found to express several cytokine genes including IL-2, IL-7, IL-11, IL-13, IL-16, lymphotoxin β, and tumor necrosis factor β. Together, these data suggested that, in mice bearing FasL+ LSA tumor, the immunotoxicity is FasL-based, whereas the hepatotoxicity, at least in part, may be FasL-independent. 相似文献
996.
This article seeks to partially fill a paucity of available data on physical performance in hunter–gatherer societies. Quantitative data are presented on various physical performance measures conducted on the Ache of eastern Paraguay, hunter–gatherers up to the 1970s and now part‐time foragers and horticulturists. The performance battery was conducted on most individuals over 10 years of age, allowing for cross‐sectional examination of growth and senescence patterns across the lifespan for both sexes. These measures tend to display steep ascents and peak in the early 20s with slight declines thereafter with age for males, whereas females demonstrate peaks in performance earlier in life, with lower or no senescence rates thereafter. The result is a convergence in physical performance between men and women at later ages. We suggest that the female physiology faces reproductive constraints to performance early in life but shifts allocation to increased work output later in life during the long human postmenopausal stage. In contrast, the male physiology maximizes work output in early adult life. These schedules of physical performance are contrasted with schedules of food production ability, which tend to occur later in life, and therefore imply that skill rather than strength alone is an important component of the human foraging niche. Am. J. Hum. Biol. 15:196–208, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
997.
Jeff Alexander Marie-France Del Guercio John D Fikes Robert W Chesnut Francis V Chisari Kyong-Mi Chang Ettore Appella Alessandro Sette 《Human immunology》1998,59(12):776-782
Using short term CTL lines derived from HLA A2/Kb transgenic mice and IFN-gamma release assays we demonstrate that the NS4.1769 epitope, is generated from natural processing of the NS4 antigen, and presented in the context of the A2/Kb molecules. Interestingly, T cell recognition of the naturally processed form of the NS4.1769 epitope was associated with significant IFN-gamma release, but no direct cytolytic activity. Epitopes of this phenotype might be of interest, in terms of therapy of chronic HCV infection by associating the benefit of localized lymphokine release with low or absent direct cytopathicity. 相似文献
998.
Psychometric Properties of Resting Anterior EEG Asymmetry: Temporal Stability and Internal Consistency 总被引:7,自引:0,他引:7
Andrew J. Tomarken Richard J. Davidson Robert E. Wheeler Linda Kinney 《Psychophysiology》1992,29(5):576-592
We examined whether resting anterior electroencephalographic (EEG) asymmetry in the alpha frequency band has psychometric properties that would be expected of a measure assessing individual differences. In each of two experimental sessions, separated by three weeks, resting EEG in midfrontal and anterior temporal sites was recorded from 85 female adults during eight 60-s baselines. Resting alpha asymmetry demonstrated acceptable test-retest stability and excellent internal consistency reliability. Analyses including other frequency bands indicated that degree of stability varied somewhat as a function of band and region. In addition, asymmetry was less stable than absolute power. Discussion focuses on the implications of the present findings for the measurement and conceptualization of resting anterior asymmetry. 相似文献
999.
Ranajit Chakraborty Ranjan Deka Li Jin Robert E. Ferrell 《American journal of human biology》1992,4(3):387-397
Because of their high degree of polymorphisms, the variable number of tandem repeat (VNTR) loci have become extremely useful in studies involving gene mapping, determination of identity and relatedness of individuals, and evolutionary relationships among populations. However, there are some concerns regarding whether or not the patterns of such genetic variation can be studied by the classical population models that are developed for studying genetic variation at blood groups and protein loci, since VNTR alleles detected by molecular size may not always be identical by descent. Although theoretical and empirical studies demonstrate that this concern is overstated, this study provides further support of the application of the traditional mutation-drift models to predict the pattern of intra- and inter-populational variation at VNTR loci. By comparing genetic variation at six VNTR loci with that at 16 blood groups and protein loci in three ethnically defined populations, we show that the patterns of variability at these two sets of loci are in general parallel to each other. Shared VNTR alleles among populations are generally more frequent than the ones which are not present in every population; the proportion of shared alleles among populations increases with increasing genetic similarity of populations; and the number of VNTR alleles is positively correlated with gene diversity at these loci. All of these observations are in agreement with the prediction of the mutation-drift models, particularly when the possibility of forward-backward mutations are taken into account. This parallelism of genetic variation at VNTR loci and blood groups/protein loci further asserts the potential of using such hypervariable loci for microevoltionary studies, where closely related populations may exhibit considerably less allele frequency differences at the classical blood group and protein loci. © 1992 Wiley-Liss, Inc. 相似文献
1000.
The caudate lobe of the liver 总被引:3,自引:0,他引:3
Y. Heloury J. Leborgne J. M. Rogez R. Robert J. Y. Barbin J. Hureau 《Surgical and radiologic anatomy : SRA》1988,10(1):83-91
Summary The caudate lobe of the liver is an independent segment straddling the right and left lobes of the liver. It is divided into 2 parts, right and left, indicated eternally by the caudate and papillary processes. It is now possible to unvestigate it by ultrasonography and computed tomography, allowing its surgical excision for tumoral disease of the superior biliary confluence.
Le lobe caudé du foie
Résumé Le lobe caudé du foie est un secteur indépendant à cheval sur les foies droit et gauche. Il est séparé en 2 parties droites et gauches, marquées extérieurement par les processus caudé et papillaire. Son exploration est actuellement possible (échographie et tomodensitométrie), ce qui autorise son exérèse chirurgicale (pathologie tumorale du confluent biliaire supérieur).相似文献