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161.
162.
Rolando Gonzlez Jos Clara García‐Moro Silvia Dahinten Miquel Hernndez 《American journal of human biology》2002,14(3):308-320
A complicated history of isolation between Fueguian and Patagonian groups (originated by the appearance of the Straits of Magellan) as much as differences in population structure and life strategies constitute important factors in the clustering pattern of those groups. The aim of this work was to test several hypotheses about population structure and history of Fueguian‐Patagonians to propose a model that incorporates predictions for future studies. R matrix methods and matrix permutation analyses were performed upon a data matrix of craniofacial measurements of 441 skulls divided into nine samples pertaining to six Patagonian and three Fueguian populations. Association of biological distances with three matrices representing several settlement patterns was tested using matrix permutation tests. Results of R matrix study show that the minimum genetic distance obtained confirms separation between Fueguians and Patagonians. Moreover, an analysis of residual variances from the expected regression line confirms admixture between Andean and Pampean populations and Araucanian groups, consistent with ethnohistorical observations. A model representing a long history of isolation between Fueguian and Patagonians, rather than a model emphasizing differences in life‐strategies, presented the best correlation with the biological distance matrix. Because similar results were already obtained in archaeological, molecular, and morphological studies, a model for the settlement of Tierra del Fuego is proposed. It is summarized by four main hypotheses that can be tested independently by different disciplines in the future. Am. J. Hum. Biol. 14:308–320, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
163.
Seiler Petra; Fischer Bernd; Lindenau Antje; Beier Henning M. 《Human reproduction (Oxford, England)》1994,9(10):1920-1926
The commercial polychlorinated biphenyl (PCB) formulation Aroclor1260 (4 mg/kg body weight), technical grade dichlorodiphenyltrichloroethane(DDT; 3 mg) and Lindane (-hexachlorocyclohexane; 0.8 mg) wereadministered orally, either separately or in combination, tosexually mature female rabbits three times per week for 1215weeks. Oviductal and uterine luminal fluid, cleavage stage embryos(day 1 post coitum), blastocysts (day 6), fetuses, exocoelicfluid and placentae (day 11) were analysed, firstly for chlorinatedhydrocarbon residues, and secondly for embryonic and fetal development.The doses applied were well tolerated by the treated animals.PCB and DDT accumulated in uterine secretions (day 6) but notin oviductal luminal fluid (day 1). Both chlorinated hydrocarbonswere found in preimplantation blastocysts. Residues in day 11fetuses were 16- (DDT) or 18-fold (PCB) higher than in day 6blastocysts. Significant amounts were also detected in placentaltissue and in exocoelic fluid. A specific accumulation of thehighly chlorinated biphenyl congener no. 180 was noted in fetuses,placentae and exocoelic fluid. The clear accumulation of thechlorinated hydrocarbon compounds in luminal fluid and embryonictissue is contrasted by rather weak effects on fertility. Nostatistically significant differences between treated animalsand controls were observed for fertilization rate and pre- andpost-implantation (up to day 11 post coitum) losses. However,in females exposed to PCB, a 20% higher loss of blastocystswas noticed, as compared with controls (P > 0.05). This effectwas shown on day 6 of embryonic development and may be due tothe embryotoxic activities of PCB. 相似文献
164.
Adriana C. Gittenberger‐De Groot Edris A.F. Mahtab Nathan D. Hahurij Lambertus J. Wisse Marco C. Deruiter Maurits C.E.F. Wijffels Robert E. Poelmann 《Anatomical record (Hoboken, N.J. : 2007)》2007,290(1):115-122
Recent advances in the study of cardiac development have shown the relevance of addition of myocardium to the primary myocardial heart tube. In wild‐type mouse embryos (E9.5–15.5), we have studied the myocardium at the venous pole of the heart using immunohistochemistry and 3D reconstructions of expression patterns of MLC‐2a, Nkx2.5, and podoplanin, a novel coelomic and myocardial marker. Podoplanin‐positive coelomic epithelium was continuous with adjacent podoplanin‐ and MLC‐2a‐positive myocardium that formed a conspicuous band along the left cardinal vein extending through the base of the atrial septum to the posterior myocardium of the atrioventricular canal, the atrioventricular nodal region, and the His‐Purkinje system. Later on, podoplanin expression was also found in the myocardium surrounding the pulmonary vein. On the right side, podoplanin‐positive cells were seen along the right cardinal vein, which during development persisted in the sinoatrial node and part of the venous valves. In the MLC‐2a‐ and podoplanin‐positive myocardium, Nkx2.5 expression was absent in the sinoatrial node and the wall of the cardinal veins. There was a mosaic positivity in the wall of the common pulmonary vein and the atrioventricular conduction system as opposed to the overall Nkx2.5 expression seen in the chamber myocardium. We conclude that we have found podoplanin as a marker that links a novel Nkx2.5‐negative sinus venosus myocardial area, which we refer to as the posterior heart field, with the cardiac conduction system. Anat Rec, 290:115–122, 2007. © 2006 Wiley‐Liss, Inc. 相似文献
165.
Krister W. Fjermestad Rene Huster Christina Thunberg Simen Stokke Claus H. Gravholt Anne‐Kristin Solbakk 《American journal of medical genetics. Part C, Seminars in medical genetics》2020,184(2):482-492
A few studies have examined neuropsychological functions, sleep, and mental health combined in Klinefelter syndrome (KS; 47,XXY). We investigated neuropsychological functions with standard tests, sleep with actigraphy, and self‐reported mental health in 30 men with KS (Mean age = 36.7 years) compared to 21 controls (Mean age = 36.8 years). Men with KS scored significantly lower on mental speed, attention span, working memory, inhibition, and set‐shifting tests, as well as overall IQ (mean effect size difference Cohen's d = 0.79). Men with KS had significantly longer night wakes, with no differences in other sleep variables (mean d = 0.34). Men with KS reported poorer mental health than controls (mean d = 1.16). Regression analyses showed neuropsychological functions explained variance in some sleep domains for men with KS but not for controls. Neuropsychological functions explained variance in some mental health domains for controls. For men with KS, however, verbal IQ was the only significant predictor of mental health. Altogether, men with KS display problems in neuropsychological functions and mental health but do not appear different from controls on most sleep parameters. Our findings indicate that relations between neuropsychological functions, sleep, and mental health differ between men with KS and controls. 相似文献
166.
167.
Weyer C Sabat R Wissel H Krüger DH Stevens PA Prösch S 《American journal of respiratory cell and molecular biology》2000,23(1):71-78
The role of surfactant protein (SP)-A in cytomegalovirus (CMV) infection of the lung was investigated. We found that SP-A binds to various immobilized human CMV proteins and those exposed on the surface of infected embryonal lung fibroblasts. The interaction between SP-A and immobilized CMV proteins was found to be calcium-dependent and inhibited by mannan, suggesting involvement of the carbohydrate recognition domain of SP-A and high-mannose carbohydrate residues of viral envelope glycoproteins. Using flow cytometry and confocal laser fluorescence microscopy in the rat model we showed that preincubation of rat CMV with SP-A stimulates its binding and internalization by rat type II pneumocytes and alveolar tissue macrophages. This effect was concentration- and Ca(2+)-dependent but was not inhibited by mannan. Therefore, the domains of SP-A involved in SP-A CMV interaction and in interaction of the SP-A/virus complex with rat lung cells are distinct. Additionally, in the human CMV model, sheep as well as human proteinosis SP-A did not significantly affect human CMV replication in embryonal lung fibroblasts. Thus, SP-A may contribute to CMV-associated pathology of the lung by increasing the efficiency of target cell infection. 相似文献
168.
169.
Using serial frozen sections, monoclonal antibodies and an indirect immunoperoxidase method, 13 fibroadenomas (FA) and 3 cystosarcomas phyllodes (CSP) were analyzed for the expression of Egp34, HEA319-antigen, leucocyte differentiation antigens CD10, CD30, CD57, CD72, CDw75, and CD77, epidermal growth factor receptor (EGFR), estrogen (ER) and progesterone receptor (PR), and transferrin receptor (CD71). Egp34, CDw75, HEA319 antigen, CD10, and CD30 turned out to be consistently expressed in different cell types constituting FA and CSP and revealed that in malignant CSP the myoepithelial compartment acquires the ability to invade the stroma. Phenomenologically, the variable mode of expression of CD57 in myoepithelial cells, of CD77 in ductal epithelium, and of CD72 in both epithelial and stromal cells is suggestive for reflecting differences in their functional state but cannot be further interpreted at present. Expression of PR and ER was restricted to duct cells and was relatively independent, non-systematical. However, expression of ER and EGFR was inverse. This was also true for EGFR and CD71 in both duct cells and myoepithelial cells of FA. In contrast, stromal cells of FA were able to co-express EGFR and CD71 in the absence of PR and ER. This suggests a hormone-independent stimulation of the stromal cell compartment, possibly leading to local proliferation as the primary event in tumorigenesis of FA. In malignant CSP, however, the main proliferating cell is an abnormally mobile, HEA319 antigen-, CD10- and CD30-positive myoepithelial cell found to co-express ERFR and CD71 which is abnormal for this cell type but encountered in (myo-)fibroblasts of FA. 相似文献
170.