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1.
目的 探讨可育男性减数分裂前期Ⅰ同源染色体的联会和重组.方法 应用铺展技术制备精母细胞联会复合体,以SCP3抗体、MLH1抗体和CREST抗血清孵育来显示联会复合体侧轴、重组位点和着丝点.结果 5例可育男性中,粗线期细胞的比例介于67%~78%;每个细胞中重组位点数平均为46.1±3.9,范围为34~61,具有显著的个体差异;联会复合体上出现缺口(gap)或未配对区(split)的细胞比例分别为14.3%和2.9%.结论 可育男性的遗传重组频率具有显著的个体差异.  相似文献   

2.
目的 :通过观察小鼠精母细胞联会复合体形成过程 ,研究减数分裂时同源染色体的配对行为。方法 :用本室改进的微铺展 硝酸银染色技术制备小鼠精母细胞联会复合体样品 ,进行电镜观察。结果 :同源染色体配对时 ,大多数是两个端粒开始接触 ,联会复合体似拉链一样扩展。有的在同源染色体内部区域的一点或多点同时开始配对 ,联会以扣纽扣方式进行。XY染色体配对仅限于部分区域。一个细胞内不同对染色体的联会不同步。同源染色体交叉在联会过程中形成 ,大多数同源染色体形成一个或多个交叉 ,但有的一个交叉也没有。结论 :大多数同源染色体以不同方式进行配对 ,交叉互换的数目也各不相同。  相似文献   

3.
目的 研究无精症和隐匿精子症染色体核型与Y染色体无精因子(azoospermia factor,AZF)微缺失的发生频率及其关系.方法 对997例无精症和隐匿精子症患者进行常规染色体核型分析及多重聚合酶链反应技术检测AZF位点.结果 在997例无精症和隐匿精子症患者中,染色体核型异常检出率28.4%,异常核型包括47,XXY、46,XY(Y<G)、46,XX、嵌合体及相互易位等.AZF微缺失总检出率17.4%.常见于46,XY及46,XY(Y<G)等核型.结论 染色体核型异常是无精症和隐匿精子症的重要遗传病因.正常核型与Y<G患者中存在较高的AZF微缺失率,对这些患者进行AZF微缺失检查有助于明确病因,避免一些不必要的临床治疗及遗传缺陷的垂直传递.  相似文献   

4.
本文对实验啮齿动物豚鼠、兔、大白鼠、小白鼠(津白Ⅰ号、津白Ⅱ号和昆明种)精母细胞联会复合体进行了观察。其联会复合体基本组成是相同的,如都包括2条侧体和两侧体间的空间中的一条中体,并有较细的横丝等,但在形态上,还存在一定差异。同源染色体和其间的联会复合体,吸附于核内膜上,核内膜加厚形成板状物,其中体明显到达核膜。性泡是X染色体和Y染色体在减数分裂期间配对。小鼠核仁密切联系性泡。性泡也可紧密贴于核膜,中体上存在有数目不等的小结节。  相似文献   

5.
目的探讨非梗阻性无精子症(NOA)与染色体异常及多态之间的关系。方法选取临床诊断为NOA的653例男性患者行常规外周血染色体G显带核型分析和Y染色体AZF微缺失检测,同时选取487例正常生育男性作为对照组。结果 653例NOA患者中,性染色体异常发生率为18.68%(122/653),常染色体异常率为2.76%(18/653),染色体多态占5.97%(39/653)。精液正常对照组中,性染色体异常率为0.62%(3/487),常染色体异常率为0.82%(4/487),染色体多态占6.98%(34/487)。NOA组与精液正常对照组进行比较:性染色体异常,有显著性差异(χ2=93.27,P0.05);常染色体异常,有显著性差异(χ2=5.52,P0.05);染色体多态性,无显著性差异(χ2=0.09,P0.05)。NOA组患者共检出Y染色体微缺失34例,其中AZFa微缺失2例,AZFb微缺失5例,AZFc微缺失18例,AZFb+AZFc微缺失5例,AZFa+AZFc微缺失1例,AZFa+AZFb+AZFc微缺失3例。结论性染色体数目异常和Y染色体结构的异常是导致NOA的一个重要因素,对NOA患者行染色体检查是十分必要的;染色体多态与NOA无明显相关性。  相似文献   

6.
目的评价经皮附睾精子抽吸术(percutaneus epididymal sperm aspiration,PESA)或睾丸精子抽吸术(testicu1ar sperm aspiration,TESA)结合卵胞浆内单精子注射(intracytoplasmic sperm injection,ICSI)治疗无精子症的临床效果。方法对290例因男性梗阻性及非梗阻性无精子症(non-obstructive azoospermia,NOA)采用PESA或TESA穿刺获取精子,女方采用长方案超排卵,然后对处于细胞分裂中期的成熟卵母细胞进行单精予注射。结果梗阻性无精子症组203例,受精率77.5%,临床妊娠率46.1%;非梗阻性无精子症组87例,受精率73.O%,临床妊娠率41.4%,两组比较其受精率及临床妊娠率均无显著性差异(P〉0.05)。结论采用PESA或TESA获取精子结合ICSI是治疗梗阻性及非梗阻性无精子症等严重的男性不育症的一种有效的方法。  相似文献   

7.
男性不育患者Y染色体AZF基因微缺失检测   总被引:1,自引:0,他引:1  
目的探讨原发性无精子症、严重少精子症及少精子症患者与Y染色体无精子因子(azoospermia factor,AZF)区微缺失的关系。方法采用多重PCR方法对对照组192例已正常生育男性和实验组448例男性不育患者进行AZF区域内的15个序列标签位点(STS)的检测。结果对照组未发现AZF基因微缺失,实验组448例患者检测出五种AZF微缺失类型共41例,总缺失率为9.2%(41/448),其中无精子症、严重少精子症和少精子症患者的缺失率分别为12.0%(19/158)、10.8%(17/157)、3.8%(5/133),无精子症和严重少精子症患者Y染色体AZF微缺失率明显高于少精子症组,差别有统计学意义(P〈0.05)。使用15个STS位点进行检测其检出率较利用欧洲男科学会(European Academy of Andrology,EAA)推荐的6个STS位点提高约14%(5/36)。结论AZF微缺失是引起原发性无精子症、严重少精子症和少精子症的重要原因之一;增加STS位点检测数有利于提高AZF微缺失的检出率。  相似文献   

8.
目的评价经皮附睾精子抽吸术(percutaneus epididymal sperm aspiration,PESA)或睾丸精子抽吸术(testicular sperm aspiration,TESA)结合卵胞浆内单精子注射(intracytoplasmic sperm injection,ICSI)治疗无精子症的临床效果。方法对290例因男性梗阻性及非梗阻性无精子症(non-obstructive azoospermia,NOA)采用PESA或TESA穿刺获取精子,女方采用长方案超排卵,然后对处于细胞分裂中期的成熟卵母细胞进行单精子注射。结果梗阻性无精子症组203例,受精率77.5%,临床妊娠率46.1%;非梗阻性无精子症组87例,受精率73.0%,临床妊娠率41.4%,两组比较其受精率及临床妊娠率均无显著性差异(P〉0.05)。结论采用PESA或TESA获取精子结合ICSI是治疗梗阻性及非梗阻性无精子症等严重的男性不育症的一种有效的方法。  相似文献   

9.
联会复合体的硝酸银染色技术   总被引:2,自引:0,他引:2  
联会复合体是减数分裂前期Ⅰ出现的一种核内非永久性细胞器,与同源染色体联会、交换、重组、分离有着密切的关系,早期研究联会复合体是通过减数分裂前期细胞连续超薄切片进行三维重组。这种方法费时费力,观察细胞数目有限,不仅不能用光镜观察,而且在一张超薄切片上不可能观察到一条完整的联会复合体,更谈不上一整套联会复合体。Counce和Meyer首次用微铺展技术,成功地把蝗虫初级精母细胞的一整套联会复合体铺展在载玻片上,运用磷钨酸染色方法在电镜下看到了联会复合体的三层结构[1]。1977年,  相似文献   

10.
目的研究无精子症和少精子症患者与Y染色体位点缺失的相关性,建立Y染色体微缺失的分子诊断方法。方法采用多重PCR技术对53例染色体核型正常的无精子症和少精子症患者以及5例正常男性的无精子因子(azoospermia factor,AZF)区域的6个STS位点进行检测。结果5例精液正常男性未检出Y染色体微缺失;53例患者中6例有AZF区域的微缺失,总缺失率为11.3%。结论Y染色体微缺失是严重生精障碍的重要原因之一,无精子因子(AZF)候选基因在精子发生过程中可能起重要作用。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

14.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

15.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

16.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

17.
18.
Introduction: The etiology of atopic dermatitis (AD) is multifactorial with interaction between genetics, immune and environmental factors.

Areas covered: We review the role of prenatal exposures, irritants and pruritogens, pathogens, climate factors, including temperature, humidity, ultraviolet radiation, outdoor and indoor air pollutants, tobacco smoke exposure, water hardness, urban vs. rural living, diet, breastfeeding, probiotics and prebiotics on AD.

Expert commentary: The increased global prevalence of AD cannot be attributed to genetics alone, suggesting that evolving environmental exposures may trigger and/or flare disease in predisposed individuals. There is a complex interplay between different environmental factors, including individual use of personal care products and exposure to climate, pollution, food and other exogenous factors. Understanding these complex risk factors is crucial to developing targeted interventions to prevent the disease in millions. Moreover, patients require counseling on optimal regimens for minimization of exposure to irritants and pruritogens and other harmful exposures.  相似文献   


19.
《Human immunology》2022,83(11):739-740
Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.  相似文献   

20.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

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