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Journal of Thrombosis and Thrombolysis - In the original publication of the article, unfortunately the given name and family name of the author’s in the author group were inadvertently...  相似文献   
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The WASP gene has been recently cloned from Xp11.23 and shownto be mutated in three patients with the Wiskott-Aldrich syndrome(WAS). We have developed a screening protocol for identifyingWASP gene alterations in genomic DNA and have identified a spectrumof novel mutations In 12 additional unrelated families. Thesemissense, nonsense and frameshift mutations involve eight ofthe 12 exons of the gene. Two mutations creating premature terminationcodons were associated with lack of detectable mRNA on Northernblots. Four amino acid substitutions, Leu27Phe, Thr48lle, Val75Metand Arg477Lys, were found In patients with congenital thrombocytopeniaand no clinically evident immune defect indicating that theWASP gene is the site for mutations in X-linked thrombocytopeniaas well as in WAS. A T-cell line from a WAS patient containedtwo independent DNA alterations, a constitutional frameshiftmutation, also present in peripheral blood leukocytes from thepatient, and a compensatory splice site mutation unique to thecell line. The distribution of eight missense mutations providesvaluable information on amino acids which are essential fornormal protein function, and suggests that sites in the firsttwo exons are hot-spots for mutation.  相似文献   
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In eutherian mammals, implantation and establishment of the chorioallantoic placenta are essential for embryo development and survival. As a maternal response to implantation, uterine stromal cells proliferate, differentiate, and generate the decidua, which encapsulates the conceptus and forms the maternal part of the placenta. Little is known about decidual functions and the molecular interactions that regulate its development and maintenance. Here we show that the receptor for the cytokine interleukin-11 (IL-11Rα) is required specifically for normal establishment of the decidua. Females homozygous for a hypomorphic IL-11Rα allele are fertile and their blastocysts implant and elicit the decidual response. Because of reduced cell proliferation, however, only small deciduae form. Mutant deciduae degenerate progressively, and consequently embryo-derived trophoblast cells generate a network of trophoblast giant cells but fail to form a chorioallantoic placenta, indicating that the decidua is essential for normal fetoplacentation. IL-11Rα is expressed in the decidua as well as in numerous other tissues and cell types, including the ovary and lymphocytes. The differentiation state and proliferative responses of B and T-lymphocytes in mutant females were normal, and wild-type females carrying IL-11Rα mutant ovaries had normal deciduae, suggesting that the decidualization defects do not arise secondarily as a consequence of perturbed IL-11Rα signaling defects in lymphoid organs or in the ovary. Therefore, IL-11Rα signaling at the implantation site appears to be required for decidua development.  相似文献   
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This study aimed at developing a dental implant movement (IM) checker for assessing quantitative dental implant mobility. The design of the instrument was based on the tooth mobility (TM) tester, which was previously developed by our group. The IM checker consists of a newly developed measuring probe which has the size of a typical dental drill so that it would be easy to measure at all regions of dental implants. The probe has a bimorph ceramics transducer for actuating an implant at constant frequency and force amplitude and for detecting acceleration response. A set of strain gauges were attached to the bimorph ceramics for detecting preload during measurement. A new digital data acquisition system was used to eliminate measurement artifacts mainly due to probe handling. The IM checker could discriminate the artificial dental implant models in the range of clinical tooth mobility M0 with variation less than 6%. The measuring time needed by five operators was less than 15 s. Accordingly, the IM checker has sufficient measuring reliability and therefore it could be introduced in dental clinics.  相似文献   
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The amyloid precursor protein is contained in plantelet alpha granules and released with degranulation. Methods are described to control for amyloid precursor protein release from platelets during blood collection and processing. In normal subjects (n = 97; age range, 44–84 years), the average plasma level of amyloid precursor protein was 6.5 ± 1.8 ng/ml.  相似文献   
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Microinfusion Using Hollow Microneedles   总被引:3,自引:0,他引:3  
Purpose The aim of the study is to determine the effect of experimental parameters on microinfusion through hollow microneedles into skin to optimize drug delivery protocols and identify rate-limiting barriers to flow. Methods Glass microneedles were inserted to a depth of 720–1080 μm into human cadaver skin to microinfuse sulforhodamine solution at constant pressure. Flow rate was determined as a function of experimental parameters, such as microneedle insertion and retraction distance, infusion pressure, microneedle tip geometry, presence of hyaluronidase, and time. Results Single microneedles inserted into skin without retraction were able to infuse sulforhodamine solution into the skin at flow rates of 15–96 μl/h. Partial retraction of microneedles increased flow rate up to 11.6-fold. Infusion flow rate was also increased by greater insertion depth, larger infusion pressure, use of a beveled microneedle tip, and the presence of hyaluronidase such that flow rates ranging from 21 to 1130 μl/h were achieved. These effects can be explained by removing or overcoming the large flow resistance imposed by dense dermal tissue, compressed during microneedle insertion, which blocks flow from the needle tip. Conclusions By partially retracting microneedles after insertion and other methods to overcome flow resistance of dense dermal tissue, protocols can be designed for hollow microneedles to microinfuse fluid at therapeutically relevant rates.  相似文献   
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A number of azomustard derivatives have been shown by t.l.c. to consist of two components. In the case of CB 10-252, 4-[bis-(2-bromopropyl)amino]-2'-carboxy-2-methylazobenzene, these have been separated by preparative h.p.l.c. They are apparently diastereoisomers, chloroform solutions of which exhibit identical transcis photoisomerism and a thermal cistrans reaction in the dark. They are also reduced identically by the soluble fraction of liver homogenate. The ability of a number of human tumour xenografts to reduce CB 10-252 was measured but the tumour with the most potent reductase activity was not inhibited by the drug in vivo.  相似文献   
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