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51.
52.
Abstract: Low and high resolution sequence specific oligonucleotide probe hybridization patterns were used to design an approach to direct sequencing of allele specific amplified cDNA. Several PCR amplifications were used to derive overlapping sequence fragments to define complete first domain sequences for a single allele. This method has been used to characterize three new DRB1 alleles in the DR52 family, DRB1*1115, DRB1* 1117, and DRB1*1319. All three alleles carry polymorphisms previously observed in other DRB alleles and underscore the importance of utilizing a directed sequencing approach for obtaining unambiguous typing results in matching for bone marrow transplantation between unrelated donor and recipient. 相似文献
53.
54.
Yasuhiro Indo 《Human mutation》2001,18(6):462-471
Congenital insensitivity to pain with anhidrosis (CIPA), also referred to as hereditary sensory and autonomic neuropathy type IV (HSAN‐IV), is an autosomal recessive hereditary disorder characterized by recurrent episodic fever, anhidrosis (inability to sweat), absence of reaction to noxious stimuli, self‐mutilating behavior, and mental retardation. The TRKA (NTRK1) gene located on chromosome 1 (1q21‐q22), consists of 17 exons and spans at least 23 kb. TRKA encodes the receptor tyrosine kinase (RTK) for nerve growth factor (NGF) and is the gene responsible for CIPA. Defects in NGF signal transduction at the TRKA receptor lead to failure to support survival of sympathetic ganglion neurons and nociceptive sensory neurons derived from the neural crest. Thirty‐seven different TRKA mutations, identified in patients in various countries, including nine frameshift, seven nonsense, seven splice, and 14 missense mutations, are distributed in an extracellular domain involved in NGF binding, as well as in the intracellular signal‐transduction domain. Extensive analysis of CIPA mutations and associated intragenic polymorphisms should facilitate detection of CIPA mutations and aid in the diagnosis and genetic counseling of this painless but severe genetic disorder with devastating complications. In addition, naturally occurring TRKA missense mutations with loss of function provide considerable insight into the structure–function relationship in the RTK family. Further, molecular pathology of CIPA would provide unique opportunities to explore critical roles of the autonomic sympathetic nervous system as well as peripheral sensory nervous system that transmit noxious stimuli in humans. Hum Mutat 18:462–471, 2001. © 2001 Wiley‐Liss, Inc. 相似文献
55.
P. V. Sergeev S. A. Chukaev Yu. A. Korovkina 《Bulletin of experimental biology and medicine》1997,124(2):786-788
Effects of estradiol and testosterone and of the antiandrogens cyproterone acetate, niftolide, and antiestrogen tamoxifen
on the activities of human erythrocyte glutathione peroxidase and glutathione reductase were studiedin vitro. In contrast to hormone preperations, antihormones in high concentrations (10−4−5×10−4 M) modified the enzyme activities. Cyproterone acetate and tamoxifen increased the activity of glutathione reductase, while
tamoxifen stimulated glutathione reductase and inhibited glutathione peroxidase. Niftolide inhibited both enzymes.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 185–187, August, 1997 相似文献
56.
不同剂量病毒唑治疗肾综合征出血热306例疗效分析 总被引:3,自引:0,他引:3
应用不同剂量病毒唑对306例肾综合征同血热患者进行治疗对比观察,发现两治疗组疗效无显著性差异,但两治疗组怀对照组相比,越期率高,肾功能恢复快,血小板数恢复早,病程缩短,并发症减少,病死率也有所下降,但无显著性差异。 相似文献
57.
The purpose of the present study was a direct comparison between simultaneous recordings of skin conductance and skin resistance. Sixty male students received a series of 30 white noise stimuli, while measures were taken continuously from four sites on the palmar surfaces of the fingers. Evaluations were made for response amplitudes, recovery, and for an approximate area measure. Magnitude of reactions and reliabilities were compared using ANOVA procedures. Behavioral concordances were estimated as correlations with the subjects' ratings of stimulus intensities. Conductance and resistance measures do not differ in amplitude, in area, or in strength of their reliabilities and behavioral concordances. No differences in any respect are found between sites. Skin conductance yields significantly (p < .01) shorter recovery times than skin resistance, which is discussed in terms of membrane permeability change. 相似文献
58.
Sbracia M Baldi M Cao D Sandrelli A Chiandetti A Poverini R Aragona C 《Human reproduction (Oxford, England)》2002,17(2):320-324
BACKGROUND: In babies born after ICSI procedures, an increase of de-novo sex chromosome abnormalities has been observed. Several hypotheses have been proposed to explain these findings: an increased rate of sex chromosome aneuploidy in sperm of oligozoospermic men, or a preferential location of the sex chromosomes in the sub-acrosomal region of the sperm nucleus which leads to a reduced DNA decondensation of this region. In order to investigate which theory may be more reliable, we studied the localization of sex chromosomes and their aneuploidy rate in sperm in men undergoing ICSI. METHODS: Using fluorescent in-situ hybridization we studied sex chromosome localization and the aneuploidy rate for sex chromosomes and chromosome 18 in 20 oligospermic men undergoing ICSI and in 10 controls. RESULTS: In 40.94 and 52.92% of cases, the X and Y chromosomes respectively were localized in the sub-acrosomal region of the sperm nucleus compared with only 14.29% of cases of chromosome 18 (P < 0.001). An increase of sex chromosome aneuploidy in sperm of oligospermic men was observed; 2.91 versus 0.69% of controls (P < 0.001). CONCLUSIONS: Sex chromosomes are localized preferentially in the sub-acrosomal region of sperm and sex chromosome aneuploidy rate in the sperm of oligozoospermic men is higher than in controls. 相似文献
59.
60.
The effects of separation and reunion on the behavior of mother and infant squirrel monkeys 总被引:1,自引:0,他引:1
J Kaplan 《Developmental psychobiology》1970,3(1):43-52
Mother and infant squirrel monkeys that lived together in a socially restricted environment were separated for a period of seven days after the infants had become relatively independent, and were then reunited. Behavioral observations before, during, and after separation indicated that (1) female infants became independent of their mothers earlier than males, (2) neither mothers nor infants were severely affected by separation, and (3) an increase in attachment occurred following reunion only when the mother had a limited history of maternal experience. These results suggest that (1) certain characteristics in the maternal behavior of the squirrel monkey facilitate readjustment in mothers and infants following maternal separation, (2) maternal experience can influence the mother-infant relationship following a period of separation, and (3) the independence of infants from their mothers may be a function of both sex and species. 相似文献