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排序方式: 共有3274条查询结果,搜索用时 15 毫秒
21.
Dermatoglyphic findings were compared in 42 patients (32 females, 10 males) with Congenital Adrenal Hyperplasia (CAH) and 110 normal controls (70 females, 40 males). In CAH males, an excess of whorls (p less than 0.001), an increased total finger ridge count (p less than 0.05), and an increased frequency of patterns in the fourth interdigital area (p less than 0.025) was found. A main line A terminating high in the hypothenar area (p less than 0.05), and a missing c-triradius or an abortive main line C (p less than 0.05) was observed in CAH females. Both sexes displayed an increase in the frequency of small radially directed hypothenar patterns (p less than 0.05) and sydney lines (p less than 0.01). 相似文献
22.
New recombinants within the MHC (B-complex) of the chicken 总被引:2,自引:0,他引:2
In a search for genetic recombinations within the major histocompatibility complex (MHC) of the chicken, the B-complex, the offspring from matings between heterozygous B15/B21 and B4/B6 animals were analysed by red cell agglutination. Among the progeny, 8,912 informative typings were performed. Four recombinants were found, all separating the B-complex loci B-F and B-G (B-F codes for Class I antigens, B-G codes for an antigen of which there is no known homologue in mammals). B-L (Class II antigen) always followed B-F. Stimulation in graft versus host reactions and in mixed lymphocyte cultures followed B-F/B-L. The mapping distance between the two loci B-F and B-G is in the range of 0.04 centimorgan. The lack of recombinants separating individual B-F loci in this study and in the studies of others might indicate that chicken MHC is less complex than those of mammalian species, but alternative explanations are also possible. So far no serologically defined recombinant separating Class I (B-F) and Class II (B-L) loci has been found. 相似文献
23.
Numerous protein kinases have been implicated in visual cortex plasticity, but the role of serine/threonine protein phosphatases has not yet been established. Calcineurin, the only known Ca2+/calmodulin-activated protein phosphatase in the brain, has been identified as a molecular constraint on synaptic plasticity in the hippocampus and on memory. Using transgenic mice overexpressing calcineurin inducibly in forebrain neurons, we now provide evidence that calcineurin is also involved in ocular dominance plasticity. A transient increase in calcineurin activity is found to prevent the shift of responsiveness in the visual cortex following monocular deprivation, and this effect is reversible. These results imply that the balance between protein kinases and phosphatases is critical for visual cortex plasticity. 相似文献
24.
von Heimburg D Hemmrich K Haydarlioglu S Staiger H Pallua N 《Cells, tissues, organs》2004,178(2):87-92
The correction of soft-tissue defects by adipose tissue transplantation often produces poor and unpredictable results. The implantation of isolated and cultured preadipocytes offers a solution to this problem since these cells differentiate into adipocytes when implanted in vivo. A field of major interest is to maximize the yield of preadipocytes isolated from adipose tissue showing only low contamination with other cell types. Aspiration and excision are two concurrent clinical ways of harvesting adipose tissue for the isolation of preadipocytes. This tissue is usually discarded after surgery. In this study, the yield of preadipocytes obtained from liposuction material was compared to that of excised adipose tissue. Furthermore, we determined the loss of precursor cells if isolation of preadipocytes was delayed for 24 h. Preadipocytes were isolated from the stromal cell fraction of human subcutaneous adipose tissue samples. Harvesting of adipose tissue by suction was performed according to the Coleman procedure (manually applied negative pressure using a 10-ml syringe with a blunt tip cannula). Isolation was either carried out within 60 min after extraction or after storage for 24 h in culture medium at 4 degrees C. Isolated preadipocytes were cultured for 24 h, trypsinized and counted in a Neubauer chamber. Our results show clearly that the yield of preadipocytes isolated from liposuction material (within 60 min after extraction and after 24 h of storage) is higher than the cell yield from excised adipose tissue. Overnight storage for 24 h leads to a significant loss of preadipocytes in excised tissue but not in liposuction material. The high yield of cells isolated from liposuction material proves that extraction by suction does not damage the stromal cell fraction in the adipose tissue. If cell isolation is not performed immediately after the operation, liposuction material is clearly the better alternative for storage. 相似文献
25.
Brand K 《Current gene therapy》2002,2(2):255-271
Matrix metalloproteinases (MMPs) are of crucial importance for the invasive behavior of primary tumors and their metastases. MMP activity is regulated by the four naturally occurring tissue inhibitors of metalloproteinases (TIMPs). It has been shown that overexpression of TIMPs in tumors of various origins leads to reduced tumor growth and formation of metastases. More recently, antitumor efficacy by in vivo gene transfer of TIMPs has been reported in several clinically relevant animal models. This review analyses the therapeutic potential of the TIMPs from a cancer gene therapeutic point of view with particular emphasis on cell culture and in vivo data. 相似文献
26.
Thairu Lucy Gehling Hanna Kafwanda Sarah Yeboah-Antwi Kojo Hamer Davidson H. Lunze Karsten 《Maternal and child health journal》2022,26(6):1375-1383
Maternal and Child Health Journal - Mothers in resource-limited areas face barriers in initiating care for ill newborns, leading to delays that may contribute to newborn mortality. This qualitative... 相似文献
27.
Point-of-care measured serum cholinesterase activity predicts patient outcome following severe burns
Karsten Schmidt Aleksandar R. Zivkovic Martin Thiele Johannes Horter Thorsten Brenner Markus A. Weigand Stefan Kleinschmidt Stefan Hofer 《Burns : journal of the International Society for Burn Injuries》2021,47(4):863-872
Risk stratification is of utmost importance in burn therapy. However, suitable bedside biomarkers to evaluate the emerging inflammatory response following burn injuries are missing. Serum cholinesterase (butyrylcholinesterase, BChE) has been shown to be a clinically relevant biomarker in acute inflammatory diseases including burns.In this observational cohort study BChE activity was measured by using point-of-care testing (POCT), a novel method in acute burn care. POCT measurements were performed at emergency room admission (ERA) of 35 patients and repeated 12, 24 and 48 h later. All patients or their legal designees gave informed consent.Patients with burn injuries showed sustained BChE activity reduction following hospital admission. BChE activity correlated negatively with burn injury severity, organ failure severity and intensive care unit resource requirements. BChE activity measured at ERA and 12 h later identified survivors and predicted 28-day patient outcome with noninferior efficacy compared to the abbreviated burn severity index (ABSI) scoring. Finally, POCT-measured BChE activity might complement ABSI scoring and possibly improve early risk stratification in acute burn care therapy. 相似文献
28.
Fausto Biancari Giovanni Mariscalco Magnus Dalén Nicla Settembre Henryk Welp Andrea Perrotti Karsten Wiebe Enrico Leo Antonio Loforte Sidney Chocron Davide Pacini Tatu Juvonen L. Mikael Broman Dario Di Perna Hakeem Yusuff Chris Harvey Nicolas Mongardon Juan P. Maureira Antonio Fiore 《Journal of cardiothoracic and vascular anesthesia》2021,35(7):1999-2006
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