人巨细胞病毒对造血系统的影响

目的 探讨人巨细胞病毒(HCMV)对造血系统的影响及其机制。方法 采用造血祖细胞体外半固体培养技术,研究HCMV AD169株对粒-巨噬系祖细胞(CFU-GM)、红系祖细胞(CFU—E)、多向造血祖细胞(CFU—Mix)及巨核系祖细胞(CFU-MK)集落生长的影响;分别用原位聚合酶链反应(IS-PCR)和聚合酶链反应(PCR)检测CFU-GM、CFU-Mix、CFU-MK及CFU-E集落细胞中的HCMV DNA;用逆转录聚合酶链反应(RT-PCR)检测CFU-E集落细胞中的晚期抗原(late antigen,LA)mRNA及CFU-MK集落细胞中的前早期抗原(immediate early antigen,IEA))mRNA;用免疫组化方法检测CFU—Mix集落细胞中HCMV早期蛋白P52。结果 HCMV AD169株在体外能明显抑制CFU—GM、CFU—E,CFU—Mix及CFU—MK的生长,抑制程度与病毒感染滴度呈剂量依赖关系;经IS-PCR或PCR检测发现病毒感染组CFU-GM,CFU-E,CFU-Mix及CFU-MK细胞中有HCMV DNA存在;RT—PCR检测发现病毒感染组CFU-MK细胞中有IEA mRNA的表达,而CFU-E细胞中的LA mRNA为阴性;免疫组化(IHC)检测发现病毒感染组CFU-Mix集落细胞中有HCMV P52的表达。结论 HCMV AD169可抑制CFU-GM,CFU-E,CFU-Mix及CFU-MK的分化和增殖;HCMV AD169对造血系统有直接损害作用。此作用可能是HCMV感染所致的粒细胞和血小板减少及贫血的原因之一。     

人巨细胞病毒感染对脐血巨核系祖细胞体外增殖的影响

目的　探讨人巨细胞病毒 (HCMV)对脐血巨核系祖细胞 (CFU Mk)体外增殖的影响及其机制。方法　采用造血祖细胞体外培养技术 ,观察、计数HCMV AD169感染的CFU Mk集落产率、抑制率、集落峰值及维持时间 ;并采用聚合酶链反应 (PCR)技术检测集落细胞内HCMV AD169DNA。结果　 1.HCMV AD169感染组集落产率较对照组明显减少 ,HCMV对CFU Mk集落的抑制程度与病毒滴度有关 ,集落产率随病毒感染滴度增高而减少 ,抑制率随病毒感染滴度增高而渐增加 ;各组集落峰值出现时间无明显差异 (P均 >0 .0 5 ) ,但各感染组集落维持时间明显短于对照组 (P <0 .0 1) ;2 .用PCR在集落细胞内检测到HCMV AD169DNA。结论　CFU Mk是HCMV的宿主细胞之一 ,HCMV能直接感染CFU Mk ;在体外HCMV AD169对CFU Mk的增殖和集落形成有明显抑制作用 ,此作用可能与临床HCMV感染后患者血小板减少有关     

巨细胞病毒抑制多向祖细胞的增殖及干预研究

目的　在体外已证实人巨细胞病毒 (HCMV)能抑制骨髓造血祖细胞的增殖。该研究观察HCMV对脐血多向造血祖细胞 (CFU Mix)体外增殖的影响及黄芪和更昔洛韦 (GCV)对此的干预作用。方法　采用造血祖细胞体外培养技术 ,观察HCMV AD1 69感染的CFU Mix集落数、抑制率、提高率、集落峰值及集落维持时间 ;用聚合酶链反应 (PCR)技术检测集落细胞内HCMV AD1 69DNA。在 1∶1 0HCMV感染组中分别加入黄芪和 /或GCV ,观察黄芪和GCV干预HCMV AD1 69对CFU Mix增殖的抑制作用。结果　① 1∶1 0 ,1∶1 0 0 ,1∶1 0 0 0三种滴度HCMV AD1 69感染的CFU Mix集落数较对照组明显减少 (P <0 .0 5 ) ,集落数随病毒感染滴度的增高而减少 ,抑制率随病毒感染滴度的增高而逐渐增加 ;②各组集落峰值出现时间无明显差异 (P >0 .0 5 ) ,但感染组集落维持时间明显短于对照组 (P <0 .0 1 ) ;③ 1∶1 0 ,1∶1 0 0 ,1∶1 0 0 0病毒感染组中检测到HCMV AD1 69DNA ;④ 1∶1 0感染组中加入黄芪和 /或GCV后 ,HCMV AD1 69感染的CFU Mix集落数明显高于未加药 1∶1 0感染组 (P <0 .0 5 )。结论　CFU Mix是HCMV的宿主细胞之一 ,HCMV能直接感染造血祖细胞 ;在体外HCMV AD1 69对CFU Mix生长和集落形成有明显抑制作用 ;黄芪和GCV有明显的抗HCMV作用 ,二者联     

人巨细胞病毒抑制粒-单及红系祖细胞的体外增殖及干预研究

探讨人巨细胞病毒 (HCMV)抑制脐血粒 -单系祖细胞的 (CFU GM)、红系爆式祖细胞 (BFU E)及红系祖细胞 (CFU E)的体外增殖和黄芪注射液与更昔洛韦(GCV)对此的干预作用 ,采用造血祖细胞体外培养、聚合酶链反应 (PCR)技术 ,培养、观察、计数CFU GM、BFU E及CFU E集落产率、抑制率、提高率 ,集落峰值时间和集落维持时间 ,并用PCR检测集落细胞内HCMV DNA。结果显示 :①HCMVAD169对CFU GM、BFU E及CFU E均有抑制作用 ,其抑制作用与HCMV浓度有关 ,高浓度 ( 1∶1 0 ,1 1 0 0 )感染组与对照组比较集落产率明显下降 (P <0 0 1 ) ,集落维持的时间明显缩短 (P <0 0 1 ) ,集落峰值时间无明显差异 (P >0 0 5) ,而低浓度组 ( 1∶1 0 0 0 )无此作用 ;②PCR检测发现在HCMV感染的造血祖细胞内存在HCMV DNA ;③在 1∶1 0感染组中 ,加入黄芪注射液与更昔洛韦后 ,HCMVAD169感染的CFU GM、BFU E及CFU E集落产率明显增加 (P <0 0 1 )。结论 :①造血祖细胞是HCMVAD169的宿主细胞之一 ,HCMVAD169能直接感染造血祖细胞 ;②在体外HCMVAD169对CFU GM、BFU E、CFU E的生长 ,集落形成有明显的抑制作用 ;③黄芪与更昔洛韦有抗HCMV作用 ,能促进受HCMV感染的造血祖细胞集落增殖     

更昔洛韦和黄芪对巨细胞病毒感染所致造血祖细胞增殖抑制的影响

目的　探讨更昔洛韦 (GCV)和黄芪对巨细胞病毒 (CMV)感染所致脐血粒 巨噬系祖细胞 (CFU GM)、红系早、晚期祖细胞 (CFU E、BFU E)、多向造血祖细胞 (CFU Mix)及巨核系祖细胞(CFU Mk)体外增殖抑制的影响。方法　采用造血祖细胞培养技术 ,培养、观察、计数巨细胞病毒AD169株 (CMV AD169)感染CFU GM、CFU E、BFU E、CFU Mix和CFU Mk后各祖细胞集落、峰期及维持时间 ;用聚合酶链反应 (PCR)检测集落细胞内CMV DNA ;根据细胞毒性实验结果 ,将GCV和黄芪作用于CMV感染的CFU GM、CFU E、BFU E、CFU Mix及CFU Mk祖细胞 ,再分别计数集落、峰期及维持时间。结果 ( 1)CMV感染组CFU GM、CFU E、BFU E、CFU Mix及CFU Mk集落数较对照组明显减少 (P <0 0 1) ;集落维持时间CMV感染组较对照组明显缩短 ;( 2 )用PCR在感染组集落细胞内检测到CMV DNA的存在 ;( 3)黄芪和 (或 )GCV作用于CMV感染的祖细胞后 ,与病毒组比较集落维持时间明显延长 ,集落数和集落增殖率明显提高 (P <0 0 1) ,黄芪组集落增殖率分别为 2 7 2 %、4 5 2 %、4 9 1%、39 0 %、11 9% ;GCV组分别为 37 4 %、74 2 %、71 7%、6 7 4 %、38 9% ;GCV 黄芪组分别为 5 3 6 %、83 8%、88 7%、87 8%、6 1 5 %。结论　CMV AD169在体外能明显抑制CFU GM、CFU E、BFU     

巨细胞病毒感染对淋巴系祖细胞增殖的影响及其干预措施

目的探讨人类巨细胞病毒（HCMV）对淋巴系祖细胞（CFU-TL）体外增殖的影响、作用机制及其干预措施。方法本实验共分为空白对照组、灭活对照组、HCMV感染组、更昔洛韦（GCV）干预组、黄芪注射液（AMI）干预组5组。采用甲基纤维素半固体培养CFU-TL集落，不同浓度HCMV-AD169持续攻击CFU-TL，用AMI、GCV粉剂干预，观察CFU-TL集落形成：用四甲基偶氮唑盐法测HCMV对宿主细胞增殖活性的影响；用PCR检测CFU-TL集落细胞内HCMV-AD169DNA。结果1．与空白对照组及灭活对照组比较，各病毒感染组CFU-TL集落产率明显减少、维持时间明显缩短（P均〈0．01），抑制程度与病毒感染滴度呈剂量依赖关系；2．HCMV感染48、72、96、120h对宿主细胞增殖活性的影响与对照组比较均有显著差异（F分别为11．412，18．058，13．259，56．360 P均〈0．01）。3．PCR检测到HCMV感染组CFU-TL集落细胞内HCMV-AD169DNA。4．与HCMV感染组比较，HCMV＋AMI组、HCMV＋GCV组CFU-TL集落产生率明显增加，集落维持时间均显著延长（P均〈0．01）。结论HCMV在体外能抑制CFU-TL集落的增殖和分化；HCMV感染患儿免疫功能低下可能与HCMV直接抑制CFU-TL有关；GCV、AMI在体外能有效干预HCMV感染所致的CFU-TL增殖抑制的发生。     

人类巨细胞病毒感染对脐血造血祖细胞增殖的影响(英文)

目的：探讨人类巨细胞病毒(HCMV)感染对脐血造血祖细胞(CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk)体外增殖的抑制作用及其机制。方法：20例脐血标本收集于正常足月顺产新生儿。实验共分5组:(1)3个HCMV感染组,每个感染组分别加入0.1 mL的103、104及105空斑形成单位(PFU)HCMV-AD169病毒液于培养体系中;(2)灭活对照组,加入同体积灭活HCMV病毒液;(3)空白对照组,不加HCMV病毒液,代之以同体积的IMDM。采用造血祖细胞体外半固体培养技术,培养、观察、计数HCMV-AD169株对脐血CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落数、抑制率和集落维持时间;并用聚合酶链反应(PCR)技术检测集落细胞内HCMV-DNA。结果：(1)在造血祖细胞培养体系中加入不同滴度的HCMV-AD169后,104和105PFU滴度感染对CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落形成均有显著的抑制作用,103PFU滴度感染对CFU-Mix及CFU-Mk集落形成有显著的抑制作用,与空白对照组和灭活对照组比较,差异有显著性(P<0.05)。病毒滴度越高,抑制程度越明显(P<0.05)。(2)104和105PFU滴度感染组CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk集落维持时间较对照组明显缩短(P<0.01),103PFU滴度感染组CFU-Mix和CFU-Mk集落维持时间较对照组明显缩短(P<0.01)。(3)PCR显示3个感染组的CFU-GM、CFU-E、CFU-Mix及CFU-Mk集落细胞内均有HCMV-AD169DNA存在。结论：HCMV-AD169能直接感染CFU-GM、CFU-E、BFU-E、CFU-Mix及CFU-Mk造血祖细胞,并抑制造血祖细胞的增殖,这可能与HCMV感染患儿出现粒细胞减少、血小板减少和贫血等造血功能紊乱有关。     

人巨细胞病毒感染对人骨髓粒－单系祖细胞生长的影响

目的探讨人巨细胞病毒(HCMV)对人骨髓粒－单系祖细胞(GM－CFUc)集落形成能力的影响。方法采用造血祖细胞培养技术，以HCMVAD169持续攻击骨髓GM－CFUc，观察计数GM－CFUc集落、簇的产率及集落的大小和维持的时间。结果①HCMV感染组GM－CFUc集落和簇的产率明显低于对照组(P＜0.01)；②HCMV感染GM－CFUc后，大集落的产率明显低于对照组；③集落维持的时间缩短，而集落出现峰值的时间无明显差异。结论在体外HCMV对GM－CFUc生长、集落的形成有明显抑制作用，提示HCMV感染患儿粒细胞减少可能与HCMV损伤GM－CFUc有关。     

特发性血小板减少性紫癜巨核系祖细胞巨细胞病毒感染的临床研究

目的特发性血小板减少性紫癜（ITP）是儿童常见的出血性疾病,其病因尚不十分清楚。很多研究表明,该病的发生与病毒感染密切相关。探讨人类巨细胞病毒（HCMV）感染巨核系祖细胞致ITP血小板减少的发病机制及其有效的治疗方法。方法HCMV相关ITP骨髓巨核细胞集落形成单位（CFU-MK）体外培养技术收集集落细胞,采用逆转录-聚合酶链反应（RT-PCR）检测HCMV晚期抗原基因mRNA,并给予更昔洛韦治疗。结果46例血清HCMV-DNAPCR阳性或血清HCMV-IgM阳性的ITP骨髓巨核细胞集落形成单位（CFU-MK）集落细胞HCMV晚期抗原基因mRNA阳性19例,更昔洛韦治疗有效16例;mRNA阴性27例,更昔洛韦治疗有效4例。阳性组疗效高于阴性组,P〈0．01,差异有统计学意义。结论HCMV可感染CFU—MK而成为1TP血小板减少的原因之一。巨核系祖细胞HCMV晚期抗原基因mRNA检测阳性者更昔洛韦治疗有效,能使血小板上升或恢复正常。     

更昔洛韦对人巨细胞病毒感染的粒-单祖细胞体外增殖的影响

目的　探讨更昔洛韦对人巨细胞病毒 (HCMV)感染的粒 单祖细胞 (CFU GM )体外增殖的影响。方法　采用造血祖细胞体外培养技术 ,用更昔洛韦干预HCMV感染的CFU GM ,观察计数CFU GM的产率、大小、峰期及维持时间。结果　①更昔洛韦组集落产率明显高于病毒组 (P <0 0 1)。②更昔洛韦组大集落所占比例明显高于病毒组 (P <0 0 1)。③更昔洛韦组集落维持时间较病毒组延长。结论　在体外 ,更昔洛韦对HCMV感染的CFU GM的生长具有促进作用。     

Allergic factors associated with the development of asthma and the influence of cetirizine in a double-blind, randomised, placebo-controlled trial: First results of ETA®

There is a common progression known as the allergic march from atopic dermatitis to allergic asthma. Cetirizine has several antiallergic properties that suggest a potential effect on the development of airway inflammation and asthma in infants with atopic dermatitis. Methods. Over a two year period, 817 infants aged one to two years who suffered from atopic dermatitis and with a history of atopic disease in a parent or sibling were included in the ETAC^® (Early Treatment of the Atopic Child) trial, a multi-country, double-blind, randomised, placebo-controlled trial. The infants were treated for 18 months with either cetirizine (0.25mg/ kg b.i.d.) or placebo. The number of infants who developed asthma was compared between the two groups. Clinical and biological assessments including analysis of total and specific IgE antibodies were performed. Results. In the placebo group, the relative risk (RR) for developing asthma was elevated in patients with a raised level of total IgE (≥ 30 kU/I) or specific IgE (≥ 0.35 kUA/I) for grass pollen, house dust mite or cat dander (RR between 1.4 and 1.7). Compared to placebo, cetirizine significantly reduced the incidence of asthma for patients sensitised to grass pollen (RR = 0.5) or to house dust mite (RR = 0.6). However, in the population that included all infants with normal and elevated total or specific IgE (intention-to-treat - ITT), there was no difference between the numbers of infants developing asthma while receiving cetirizine or placebo. The adverse events profile was similar in the two treatment groups. Discussion. Raised total IgE level and raised specific IgE levels to grass pollen, house dust mite or cat dander were predictive of subsequent asthma. Cetirizine halved the number of patients developing asthma in the subgroups sensitised to grass pollen or house dust mite (i.e. 20% of the study population). In view of the proven safety of the drug, we propose this treatment as a primary pharmacological intervention strategy to prevent the development of asthma in specifically sensitised infants with atopic dermatitis.     

Resurgence of measles in Singapore: profile of hospital cases

OBJECTIVE: To ascertain the profile of cases of measles seen at a general hospital during a recent outbreak that occurred despite a measles vaccination program. METHODOLOGY: A retrospective study from January 1991 to March 1998. All patients with measles (ICD code 055. 9) seen at the emergency unit or as inpatients were included. RESULTS: There were 87 cases identified. The diagnosis was clinical in all and proven serologically in 71%. Eighty-five per cent of the cases occurred between January 1997 and March 1998. There was a bi-modal age distribution with peaks in the very young (相似文献   

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孤独症谱系障碍(autistic-spectrum disorders,ASDs)近年来患病率逐年攀升至1%左右,其症状往往伴随终生,成为严重威胁儿童健康和发展的神经发育性疾患;注意缺陷多动障碍(attention deficit hyperactivity disorder,ADHD)是儿童期最常见的精神障碍,国内报道患病率为4.13%～5.83%,其症状可延续至青少年期,甚至到成年期[1]。这两类精神障碍在成年期的临床表现、共患病、治疗策略和预后与儿童期有哪些不同呢?本文通过回顾相     

EXCITING NEW TREATMENT APPROACHES FOR PATHYPHYSIOLOGIC MECHANISMS OF SICKLE CELL DISEASE

During the past several decades, our understanding of the complex pathophysiology of vasoocclusion associated with sickle cell disease has improved greatly. Interaction of genes, hemoglobin molecules, red cell membrane and metabolic changes, cell-cell interactions and cell-plasma interactions, red cell adhesion to vascular endothelium, activation of coagulation, and vascular reactivity play a role in vaso occlusion. Penicillin prophylaxis of pneumococcal infections and appropriate use of blood transfusions and other supportive measures improved survival of sickle cell patients. Hydroxyurea made a major impact on sickle cell therapy when it was shown to decrease acute painful episodes, acute chest syndrome, and the need for blood transfusion in adults. Significant experience in the use of hydroxyurea has been accumulated in older children. The benefits and risks of hydroxyurea for younger children and long-term risks in all patients will be evaluated in future investigations. Other promising therapies include butyrate compounds, clotrimazole, magnesium supplementation, poloxamer 188, antiadhesion agents, anticoagulant approaches, and nitric oxide. Hemopoietic transplantation remains the only curative therapy. However, several transgenic mouse models are available for studies of gene therapy or other treatment approaches on biochemical, cellular, and pathologic effects of mutant genes.     

Infiltrations of Epstein-Barr virus-carrying cells in granular lymphocyte-proliferative disorders corresponding to chronic active Epstein-Barr virus infection

A 21-year-old man with granular lymphocyte-proliferative disorders (GLPD) associated with chronic active Epstein-Barr virus (EBV) infection is described. Chromosomal analyses revealed several clonal abnormalities and two of them were mainly repetitious. High copy numbers of monoclonal EBV genome were also detected in the proliferative large granular lymphocytes (LGLs), indicating the monoclonal expansion of EBV-infected LGLs. The patient had an indolent course for several years, and there was no evidence of infiltrations of his bone marrow until the end stage. At autopsy, microscopic studies revealed marked infiltrations of LGL in the liver and spleen, and the infiltrating cells were NK-cell immunophenotype. The infiltrated LGLs showed latency I.     

LUTEINIZING HORMONE RECEPTOR MUTATIONS IN DISORDERS OF SEXUAL DEVELOPMENT AND CANCER

Human male sexual development is regulated by chorionic gonadotropin (CG) and luteinizing hormone (LH). Aberrant sexual development caused by both activating and inactivating mutations of the human luteinizing hormone receptor (LHR) have been described. All known activating mutations of the LHR are missense mutations caused by single base substitution. The most common activating mutation is the replacement of Asp-578 by Gly due to the substitution of A by G at nucleotide position 1733. All activating mutations are present in exon 11 which encodes the transmembrane domain of the receptor. Constitutive activity of the LHR causes LH releasing hormone-independent precocious puberty in boys and the autosomal dominant disorder familial male-limited precocious puberty (FMPP). Both germline and somatic activating mutations of the LHR have been found in patients with testicular tumors. Activating mutations have no effect on females. The molecular genetics of the inactivating mutations of the LHR are more variable and include single base substitution, partial gene deletion, and insertion. These mutations are not localized and are present in both the extracellular and transmembrane domain of the receptor. Inactivation of the LHR gives rise to the autosomal recessive disorder Leydig cell hypoplasia (LCH) and male hypogonadism or male pseudohermaphroditism. Severity of the clinical phenotype in LCH patients correlates with the amount of residual activity of the mutated receptor. Females are less affected by inactivating mutation of the LHR. Symptoms caused by homozygous inactivating mutation of the LHR include polycystic ovaries and primary amenorrhea.     

A profile of respiratory symptoms in urban and rural South Australian school children

This report describes the cross-sectional analyses of data from the first year of a longitudinal study using questionnaire and respiratory function data over a 5 year period from a sample of rural South Australian school children. The cumulative or lifetime prevalences of respiratory symptoms were estimated in 825 rural and 1261 urban school children aged between 5 and 15 years in order to determine if the prevalence rates differed between rural and urban school children. The study found the overall cumulative prevalence of asthma and/or wheezy breathing (AWB) to be 24.1% in the rural school children compared to 27.6% in the urban school children. Most children developed AWB symptoms before the age of 7 years, with 20% reporting moderately severe symptoms and 10% having more than one attack per fortnight. The cumulative prevalence of bronchitis, loose/rattly cough (BLRC) differed significantly between the rural school children (34.1%) and urban school children (47.9%). The BLRC symptoms preceded the development of AWB in many cases. Urban school children also reported a higher prevalence of atopic conditions.     

Personality profiles and heart rate variability (vagal tone) in children with recurrent abdominal pain

The aim of the study was to explore psychological factors and autonomic activity in children with recurrent abdominal pain and to compare them with those in a control group of healthy children. The Personality Inventory for Children was used for assessment of developmental, emotional and psychosocial factors in 25 children with recurrent abdominal pain (age, 7-15 y). Parasympathetic and sympathetic functions in these children and in 23 healthy control subjects (age, 7-13 y) were also investigated, non-invasively using a computerized polygraph. Vagal tone (parasympathetic function) was indexed by calculation of respiratory sinus arrhythmia in beats/min. Skin conductance (sympathetic function) was recorded by the constant current method. On the Personality Inventory for Children, 16 patients had high scores on somatic concern. Several patients had scores in the clinical range for depression, withdrawal and anxiety, but the mean scores for these personality profile scales were well within the normal range of healthy children. Interestingly, there was a spike on the L (Lie)-scale for most of the patients and 15 patients had scores above or close to the clinical cut-off value. As compared with the scores in healthy children, vagal tone and sympathetic tone were normal. Conclusion: Many children with recurrent abdominal pain have scores in the clinical range for depression, withdrawal, anxiety and L-scale indicating coping problems, denial and a trend towards somatic concern that may contribute to the evolution of abdominal pain. Autonomic nerve activity was not disturbed in these children.     

Hauttemperaturen verschiedener Körperoberflächenareale des Rumpfes bei Säuglingen

Summary In two groups of infants (3–53 weeks old) skin temperatures were controlled in different areas of the trunk—i.e.: regions of sternum, lungs, heart, liver, spleen, kidneys—at different room-temperatures (group I: 21–25°C; group II: 29–32°C). Rectal temperatures of some probands in both groups also had been controlled simultaneously. A definite change in the reaction to heat was proofed in different periods of the first year of life. In higher environmental temperatures the skin temperature was almost constant at every controll-point of the skin, even in older infants. In lower environmental temperatures the skin temperatures lowered continuously with age till 7. to 9. moth. From 10. to 12. month the lowering of skin temperature discontinued. The rectal temperatures were relatively constant in all infants. Only in infants from 7. to 12. month, whose skin temperatures were controlled in lower as well as in higher environmental temperatures, a tendency to higher rectal temperatures was proofed in warmer environmental temperatures.The significance of these results is discussed.

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Untersuchungen mit Unterstützung durch die Deutsche Forschungsgemeinschaft.