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41.
W C Light R E Reisman M Shimizu C E Arbesman 《The Journal of allergy and clinical immunology》1977,59(5):391-397
Fifteen patients were studied who had unusual reactions following insect stings. These included serum sickness, neurologic disease, renal disease, and delayed hypersensitivity-type reactions. The clinical features are briefly outlined. Measurements were made of serum venom-specific IgE and IgG antibodies. These antibodies were present in some patients and in these instances suggested an immunologic pathogenesis for the reactions. Alternative etiologies for the unusual reactions are also discussed. 相似文献
42.
The effect of adrenergic and cholinergic drugs on short incubation “active” E rosette formation was studied in 19 patients with bronchial asthma and 17 healthy controls. Both groups had an equal absolute number of baseline “active” E rosettes, but the asthmatics demonstrated a higher percent baseline value. The beta adrenergic drug isoproterenol (10?3 M) inhibited the formation of “active” E rosettes in asthmatics by only 18.0% as compared to a 60.8% inhibition in the control group. Carbamylcholine (10?5 M) a cholinergic agonist, also showed a lower than normal response in asthmatics, 34.3% enhancement of “active” E rosetting compared to a 52.4% enhancement in the controls. The alpha adrenergic agent phenylephrine (10?5 M) exhibited equal enhancing effects in both groups, 34.2% in the asthmatics and 36.5% in the controls. Isoproterenol (10?3 M) had a minimal effect on inhibition of long incubation “total” E rosettes in both groups studied. The beta adrenergic abnormality conforms to the beta blockade theory of asthma of Szentivanyi. The cholinergic abnormality is unexplained in view of the hyperresponsiveness of patients with asthma to cholinergic agents in vivo. Patients with bronchial asthma probably have an autonomic dysfunction that may play a role in the pathogenesis of their disease. 相似文献
43.
Summary Genetic analyses of n-alkane non-utilizing mutants of the yeast Yarrowia (Saccharomycopsis) lipolytica were continued. By analyses of inter-mutant complementation and recombination a total of 26 genetic loci have been identified. Mutations representing these loci have phenotypes characteristic of defects in substrate uptake or in one or more of the enzymatic activities making up the hydroxylase complex. Tests of 14C n-hexadecane uptake by a set of alkane-negative mutants representing the 26 loci show that 16 of the mutations cause a significant reduction in n-alkane uptake. N-alkane uptake by Y. lipolytica is shown to be inducible and to be inhibited by the metabolic poisons 2–4 dinitrophenol and KCN. The latter observation indicates that n-alkane uptake of Y. lipolytica is due to active transport. 相似文献
44.
R E Ruffin J D Fitzgerald A S Rebuck 《The Journal of allergy and clinical immunology》1977,59(2):136-141
The effects of the beta 2-adrenergic agonist, salbutamol, 200 mug, and the cholinergic antagonist, Sch 1000, 40 mug, have been compared in 25 asthmatic patients using a single dose, double-blind, crossover trial design. Salbutamol aerosol produces a greater degree of bronchodilatation than Sch 1000 aerosol during the initial three hours following drug administration. There is no significant difference in the bronchodilator effects of the two drugs in the interval four to eight hours after drug administration. Nonatopic patients showed less difference in bronchodilator response to each of the two drugs than atopic patients. Neither drug showed any significant adverse effect on blood pressure, pulse rate, or electrocardiogram. In six asthmatic patients the effect of the combination of salbutamol, 200 mug, and Sch 1000, 40 mug, was evaluated. The combination produced a longer duration of bronchodilatation than either drug alone when compared to placebo. 相似文献
45.
The prognostic role of the extent of Y microdeletion on spermatogenesis and maturity of Sertoli cells 总被引:6,自引:0,他引:6
Kleiman SE Bar-Shira Maymon B Yogev L Paz G Yavetz H 《Human reproduction (Oxford, England)》2001,16(3):399-402
Substantial involvement of the Y chromosome in sexual development and spermatogenesis has been demonstrated. Over the last decade, varying extent of Y chromosome microdeletions have been identified among infertile patients with azoospermia or oligozoospermia. These microdeletions were clustered in three main regions named AZFa, AZFb, and AZFc. Analysis of the Y chromosome microdeletion was found to be of prognostic value in cases of infertility, both in terms of clinical management as well as for understanding the aetiology of the spermatogenesis impairment. However, the accumulated data are difficult to analyse, due to the variable extent of these deletions, the different sequence-tagged sites (STS) used to detect the microdeletions, and the non-uniformity of the histological terminology used by different investigators. This debate discusses the chances of finding testicular spermatozoa in men with a varying extent of Y chromosome microdeletions. The genotype and germ cell findings in men with AZFa microdeletions as well as those that include more than a single AZF region are reviewed, as is the effect of Y chromosome AZF microdeletions on the maturity of the Sertoli cells. 相似文献
46.
Co-localization of neuropeptide Y, vasoactive intestinal polypeptide and dynorphin in non-noradrenergic axons of the guinea pig uterine artery 总被引:5,自引:0,他引:5
Two major populations of perivascular axons containing immunoreactivity to neuropeptide Y (NPY) have been revealed in the main uterine artery of the guinea pig by immunohistochemical procedures which allow the simultaneous visualization of two antigens. One population contained immunoreactivity to dopamine-beta-hydroxylase (D beta H) and was presumably noradrenergic. The other main population of axons with NPY-like immunoreactivity (NPY-LI) did not have D beta H-like immunoreactivity (D beta H-LI) and was presumably non-noradrenergic. These non-noradrenergic axons also contained immunoreactivity to vasoactive intestinal polypeptide (VIP) and dynorphin (DYN). Indeed, nearly all axons with VIP-LI also contained NPY-LI and DYN-like immunoreactivity (DYN-LI). NPY constricted the uterine artery perfused in vitro, whilst VIP dilated uterine arteries preconstricted with noradrenaline or NPY. Thus, we have evidence for the coexistence of a vasoconstrictor peptide and a vasodilator peptide in the same non-noradrenergic perivascular axons, which also contain an opioid peptide, dynorphin. 相似文献
47.
Mitochondrial DNA and Y-Chromosome Variation in the Caucasus 总被引:7,自引:3,他引:7
I. Nasidze E. Y. S. Ling D. Quinque I. Dupanloup R. Cordaux S. Rychkov O. Naumova O. Zhukova N. Sarraf-Zadegan G. A. Naderi S. Asgary S. Sardas D. D. Farhud T. Sarkisian C. Asadov A. Kerimov M. Stoneking 《Annals of human genetics》2004,68(3):205-221
We have analyzed mtDNA HVI sequences and Y chromosome haplogroups based on 11 binary markers in 371 individuals, from 11 populations in the Caucasus and the neighbouring countries of Turkey and Iran. Y chromosome haplogroup diversity in the Caucasus was almost as high as in Central Asia and the Near East, and significantly higher than in Europe. More than 27% of the variance in Y‐haplogroups can be attributed to differences between populations, whereas mtDNA showed much lower heterogeneity between populations (less then 5%), suggesting a strong influence of patrilocal social structure. Several groups from the highland region of the Caucasus exhibited low diversity and high differentiation for either or both genetic systems, reflecting enhanced genetic drift in these small, isolated populations. Overall, the Caucasus groups showed greater similarity with West Asian than with European groups for both genetic systems, although this similarity was much more pronounced for the Y chromosome than for mtDNA, suggesting that male‐mediated migrations from West Asia have influenced the genetic structure of Caucasus populations. 相似文献
48.
A new haplogroup pattern displayed in Fujian Han in China 总被引:1,自引:0,他引:1
Yu M Zhang Y Xue Y Chen F Wang Q Huang X Wang B Yu Y Liu A Ma L Shi R Lu F Shi Z Zhang Y Cheng W Ai Q Xu F Huang C Chen B Yang H Kang X Sun Y Zhang G Li P Fu S 《Journal of human genetics》2002,47(2):95-98
Human Y-chromosomal binary polymorphisms have been considered to preserve the paternal genetic legacy and provide evidence
on human evolution and the genetic relationships among and demographic history of different populations. To reveal the genetic
origin and immigration of the Fujian Han, 13 binary markers on the Y chromosome were used to screen Fujian Han by allele-specific
polymerase chain reaction. The results indicated that the M9G marker was highly prevalent (96.20%), suggesting a significant genetic drift. In addition, M122C frequency was only 22.78%, and M45A and M103T were default. The distinctive haplogroup frequencies (H1, H5, and H6/7/8) imply that the haplogroup pattern is a relatively ancestral and interim type.
Received: October 13, 2001 / Accepted: December 3, 2001 相似文献
49.
W C Light R E Reisman V S Ilea J I Wypych T Okazaki C E Arbesman 《The Journal of allergy and clinical immunology》1976,58(2):322-329
The antigenic and allergenic properties of phospholipase A2 (PLA2) and whole bee venom were compared by measuring the IgG and IgE antibody responses in animals and man. Precipitating antibodies raised in rabbits and reaginic and other antibodies raised in mice reacted about equally with both bee venom and PLA. The majority of human sera containing bee venom-specific IgE also contained PLA-specific IgE, although in somewhat lower titers. Similarly, most human sera with significant amounts of total antibodies reacting with bee venom also had antibodies reacting with PLA. Histamine and SRS-a release from leukocytes of sensitive patients followed challenge with whole bee venom and PLA in the majority of instances. However, mediator release from several patients' cells was obtained with bee venom only. These studies suggest that although PLA is a major allergen and antigen in bee venom, significant exceptions in patients' reactivity may limit its potential diagnostic and therapeutic usefulness. 相似文献
50.
人工流产胎儿标本23例,孕龄10~41周,用免疫组织化学ABC法,研究人胎儿脊髓神经肽Y样神经元的发育和分布。结果在胎龄第10周,发现脊髓后角浅层(RextdⅠ、Ⅱ层)已有神经肽Y样免疫阳性神经元胞体存在,且阳性神经元总数随胎龄的增加而递增,并向后角深层(RexedⅢ~Ⅳ层)扩展神经肽Y样阳性纤维,在胎龄第10周,不仅出现于脊髓的灰质和白质,而且见于脊髓的被膜。随胎龄的增长,免疫阳性反应纤维相对集中于脊髓的植物性神经中枢的所在部位,揭示在妊娠早期,神经肽Y可能与脊髓植物神经元的发育及其功能的调节有关。 相似文献