早产儿支气管肺发育不良危险因素前瞻性队列研究

目的 探讨早产儿支气管肺发育不良(BPD)的发生率及危险因素.方法 应用前瞻性队列研究的方法,对我院产科2009年1月至2010年6月出生的所有活产早产儿进行研究,统计BPD发生率,并分析相关危险因素.结果 (1)共有425例早产儿入组研究,其中男266例,女159例;胎龄(33.9±2.4)周(26～ 36周);出生体重(2038±660) g(770 ～3150 g),其中极低出生体重儿85例,超低出生体重儿7例.发生BPD 45例,发生率10.6％,死亡(包括自动出院撤机后死亡)7例,BPD病死率15.6％.BPD患儿胎龄≤32周36例(80.0％),出生体重＜1500 g 29例(64.4％).(2)多因素Logistic回归分析显示胎龄＜30周(OR =3.10)、出生体重＜1500 g(OR=2.29)、感染性肺炎(OR =2.74)、动脉导管未闭(OR =2.12)、机械通气(OR =9.57)、H2受体抑制剂( OR=1.36)、应用碳青霉烯类抗生素＞4周(OR=2.59)是BPD发病的独立危险因素(P均＜0.05).结论 早产儿发生BPD的独立危险因素较多,需要综合防治才能有效控制BPD的发生.     

极低出生体重儿早期救治结局的影响因素分析

目的 分析极低出生体重儿(VLBWI)临床特点及影响早期救治结局的相关因素.方法 对2008年1月至2013年1月我院新生儿重症监护室(NICU)住院的VLBWI临床资料进行回顾性分析,对影响早期救治结局的相关因素进行Logistic回归分析.结果 VLBWI主要分布在1250 ～ 1499 g(57.1％),胎龄29～32周(72.3％).新生儿呼吸窘迫综合征(RDS)在＜1000 g组、胎龄25～28周的发生率明显高于其他组;喂养不耐受在1250～1499 g组的发生率明显高于其他组;肺炎在33～ 36周的发生率明显高于其他组;贫血在1250～1499 g的发生率明显高于其他组.临床转归差108例(38.6％),转归好172例(61.4％).多因素Logistic回归分析显示,胎龄越大VLBWI的转归越好(OR=0.979,95％CI0.955 ～ 0.997),RDS(OR=3.739,95％ CI1.955～7.007)、肺炎(OR =2.315,95％CI1.097 ～4.677)是其危险因素.结论 对VLBWI可根据胎龄及出生体重不同,有目的的预防及治疗并发症,可以提高存活率.     

小胎龄早产儿支气管肺发育不良发生率和危险因素分析

目的探讨小胎龄早产儿支气管肺发育不良(BPD)的发生率和高危因素。方法回顾性分析2008年5月至2011年12月我院新生儿科收治、胎龄≤32周、且存活28天以上的早产儿临床资料,发生BPD的早产儿为BPD组,按1∶2的比例随机选取未发生BPD的早产儿为对照组。结果共纳入197例早产儿,BPD组28例,BPD发生率14.2%,早产儿随胎龄和出生体重降低BPD发生率明显增加,各胎龄段和体重组差异均有统计学意义(χ2=32.269,30.244,P=0.000)。通过对23个单因素的分析发现,BPD组和对照组胎龄、出生体重、吸氧时间、最高吸入氧浓度、住院时间、气管插管机械通气、应用肺表面活性物质治疗、贫血、使用美罗培南、第10天体重/出生体重比值、氧合指数<300和生后第1次血气评分值12个单因素差异有统计学意义(P均<0.05);多因素Logistic回归分析发现,出生体重低(OR=0.996)、吸氧浓度高(OR=0.898)、第10天体重/出生体重比值小(OR=1.069)为发生BPD的高危因素(P均<0.05)。中重度BPD组与轻度BPD组相比,窒息和使用利尿剂比例高、吸氧时间长、生后第1次血气评分低,差异有统计学意义(P均<0.05)。结论出生体重低、吸入高浓度氧、第10天体重/出生体重比值低为小胎龄早产儿发生BPD的高危因素。     

极低出生体质量儿输血相关危险因素分析

目的分析极低出生体质量儿输血相关危险因素并探讨贫血预防策略。方法选择2015年1月至2016年6月收治的胎龄37周且出生体质量1 500 g的新生儿,根据是否输血分成输血组和非输血组,比较两组的一般状况、并发症等,同时分析影响输血的危险因素及与输血量相关的因素。结果纳入150例极低出生体质量儿,输血组108例、非输血组42例。与非输血组相比,输血组的胎龄及出生体质量更小,基础血红蛋白更低,肠外营养时间更长,住院采血总量更多,差异均有统计学意义(P0.05);输血组的支气管肺发育不良(BPD)、急性呼吸窘迫综合征(ARDS)、动脉导管未闭(PDA)的发生率高于非输血组,差异均有统计学意义(P0.05)。线性回归分析示胎龄、出生体质量越小,肠外营养时间越长,住院采血总量越多,则输血量越大(P0.05)。结论极低出生体质量儿的胎龄、出生体质量、肠外营养时间及住院采血总量等对输血风险及输血量存在不同程度的影响,输血患儿BPD、RDS、PDA的发病率更高。     

早产儿视网膜病的危险因素分析

目的前瞻性调查早产儿视网膜病(ROP)的发病率,并分析其相关危险因素。方法对2005年1月1日至2007年10月31日收治的胎龄<34周、出生体重<2000g的早产儿和低出生体重儿,按时进行ROP筛查,并记录完整的临床资料,调查ROP发病率并分析相关危险因素。结果345例早产儿纳入研究,完成ROP随访323例,42例发生ROP(13.0%),手术6例(1.9%)。危险因素分析提示,窒息、吸氧时间>5d、感染、贫血、酸中毒与ROP相关(P<0.05),胎龄(OR=0.751)、呼吸暂停(OR=2.028)、感染(OR=2.794)和输血(OR=2.136)是ROP独立作用的因素。结论本研究ROP发病率为13.0%,窒息、吸氧时间>5d、贫血、感染、酸中毒与ROP相关,胎龄、呼吸暂停、感染、输血是ROP的独立危险因素。     

早产儿呼吸窘迫综合征和湿肺的临床对照研究

目的 了解早产儿发生呼吸窘迫综合征(RDS)和湿肺[又称暂时性呼吸困难(TTN)]的危险因素、临床表现、治疗和并发症.方法 采用回顾性病例对照研究方法,分析99例在2013年就诊于北京大学第三医院儿科新生儿重症监护病房的RDS或TTN早产儿病例资料,其中RDS 30例,TTN 69例.99例中男54例,女45例.观察RDS组和TTN组围生期危险因素、呼吸支持、并发症等.组间比较采用x2检验或Fisher's精确概率法或独立样本t检验.结果 99例早产儿出生胎龄(31.9±2.2)周;出生体重(1 661 501)g.RDS组和TTN组胎龄和出生体重差异均有统计学意义[(29.5±2.5)比(32.0±3.2)周,(1 115 ±415)比(1 660±531)g,t=6.046、5.916,P=0.002、0.001].生后0～2 h内,RDS组和TTN组pH分别是7.25±0.09和7.30±0.01(t=-2.144,P=0.046),氧分压(PaO2)分别为(55±20)和(41 ±2)mmHg(1 mmHg=0.133 kPa,t=2.863,P=0.001),氧合指数分别为(149±58)和(100±9)mmHg(t =3.379,P=0.003).RDS组和TTN组分别有30例和12例应用肺表面活性物质(P＜0.01).RDS组25例应用有创机械通气,5例应用无创机械通气,TTN组44例应用无创机械通气,25例应用鼻导管吸氧.RDS组和TTN组发生呼吸机相关肺炎的例数分别是14例(46.7％)和4例(5.8％)(P=0.038),发生动脉导管未闭的例数分别为19例(63.3％)和9例(13.0％)(P=0.025),发生3度或4度脑室内出血的例数分别为9例(30.0％)和2例(2.9％)(P=0.041),发生支气管肺发育不良的例数分别为12例(40.0％)和5例(7.2％)(P=0.019).结论 RDS和TTN是早产儿生后早期呼吸困难的主要病因.早产儿RDS的特点是多见于胎龄＜30周的超低出生体重儿或极低出生体重儿,早期酸中毒程度重,有创机械通气应用比例高,并发症多.早产儿TTN的特点是多见于胎龄30 ～34周的低出生体重儿,早期低氧血症程度重,无创机械通气比例高.     

新生儿输血相关性坏死性小肠结肠炎危险因素分析

目的探讨新生儿输血相关性坏死性小肠结肠炎(transfusion associated necrotizing enterocolitis,TANEC)发生的临床相关危险因素,以期减少新生儿坏死性小肠结肠炎(necrotizing enterocolitis,NEC)的发病率。方法收集2017年1月至2018年6月于兰州大学第一医院收治并接受输血治疗的新生儿的临床相关资料,包括围生期因素、患儿基本情况、合并症,根据输血后48 h内NEC发生与否分为TANEC组和非TANEC组,对两组患儿的临床资料进行分析。结果单因素分析结果显示:两组患儿在分娩方式、胎龄、出生体重、新生儿败血症、动脉导管未闭(patent ductus arteriosus,PDA)、新生儿呼吸窘迫综合征(neonatal respiratory distress syndrome,NRDS)和贫血严重程度上的差异有统计学意义(P<0.05)。多因素Logistic回归分析结果显示,胎龄(P<0.05,OR=0.772,95%CI:0.684~0.871)、出生体重(P<0.05,OR=0.236,95%CI:0.079~0.711)是TANEC的保护因素,贫血程度(模型1中P<0.05,OR=3.129,95%CI:1.003~9.756;模型2中P<0.05,OR=3.449,95%CI:1.024~11.609)及新生儿败血症(模型1中P<0.05,OR=6.327,95%CI:1.732~23.720;模型2中P<0.05,OR=8.154,95%CI:2.122~31.336)是TANEC的危险因素。结论导致TANEC发生的因素是多方面的,输血时,胎龄越大,出生体重越高,发生NEC的风险越小;而合并新生儿败血症、贫血程度越重,发生TANEC的风险越高。临床上需采取综合措施预防新生儿贫血,并根据患儿的具体情况及贫血的程度制定合理的临床策略,尽量避免输血以减少TANEC的发病率,改善患儿预后。     

极低出生体重儿早发血小板减少症多因素相关分析

目的探讨极低出生体重儿早发血小板减少症的相关因素。方法选择2011—2013年我院NICU收治的极低出生体重儿进行回顾性研究。根据生后72 h内有无血小板减少症分为早发血小板减少症组和无早发血小板减少症组,对两组患儿临床情况进行比较。结果108例研究对象入选,发生早发血小板减少症45例(41.7%),患儿血小板计数在中位数8天恢复正常。男婴(OR=6.036)、早发感染(OR=8.358)及孕母患妊娠期高血压疾病(OR=5.990)与极低出生体重儿早发血小板减少症相关(P<0.05),胎龄、出生体重、胎膜早破、窒息、产前应用地塞米松、呼吸窘迫综合征等对极低出生体重儿早发血小板减少症无明显影响。结论早发血小板减少症是极低出生体重儿的常见合并症,男婴、早发感染及孕母患妊娠期高血压疾病是极低出生体重儿早发血小板减少症的危险因素。     

极低及超低出生体重儿肺出血的影响因素及预后分析

目的 探讨极低及超低出生体重(出生体重≤1200g)早产儿肺出血的影响因素及预后.方法 回顾性分析2010年1月至2015年12月于中国医科大学附属盛京医院第二新生儿科住院、出生体重≤1200g、住院期间发生肺出血的极低及超低出生体重儿临床资料,同期住院、相同体重范围非肺出血早产儿作为对照组.比较两组母孕期及新生儿期特点,多元回归分析探讨肺出血影响因素,了解肺出血新生儿的近期预后.结果 肺出血新生儿(肺出血组)71例,对照组364例.肺出血发生于 3d 以内者57例(占80.3%),肺出血组胎龄(28.2±1.7)周、出生体重(936±192)g,均明显低于对照组[(29.5±2.1)周,(1033±134)g,t分别为4.776、-5.145,P<0.01].肺出血组呼吸窘迫综合征(RDS)(76.1%)、肺表面活性物质治疗(76.1%,其中≥2次使用率9.9%)、动脉导管未闭(PDA)(66.2%)比例均明显高于对照组[41.2%、30.8%(4.1%)和38.7%,χ2值分别为33.457、28.970(4.074)和32.798,P<0.05].肺出血组产前类固醇激素治疗率(21.1%)亦明显低于对照组(41.2%,χ2=10.177,P<0.01).多因素Logistic逐步回归分析显示,RDS(OR=3.739,95%CI 1.383-10.113,P<0.05)、PDA(OR=2.206,95%CI 1.205-4.093,P<0.05)及5 min Apgar评分<7(OR=2.851,95%CI 1.191-6.828)是肺出血的独立危险因素;出生体重大(OR=0.998,95%CI 0.996-1.000,P<0.05)及母孕期应用激素 (OR=0.432,95%CI 0.224-0.834,P<0.05)是肺出血的保护因素.肺出血组颅内出血、早产儿视网膜病及重度支气管肺发育不良发生率(16.9%、12.7%及18.3%)明显高于对照组(5.8%、4.4%及2.2%,χ2值分别为36.824、7.520及33.568,P<0.01).肺出血组病死率(49.3%)亦明显高于对照组(14.0%,χ2=46.634,P<0.01).结论 多种围生期因素与肺出血有关;预防早产及产前类固醇激素治疗有助于预防肺出血;肺出血新生儿不良预后发生率高.     

重组人类促红细胞素和铁剂在极低出生体重儿中的应用研究

目的评价重组人类促红细胞素(rhFPO)和铁剂对极低出生体重儿(VL-BW)输血的影响及预防早产儿贫血的效果.方法对59例出生体重≤1500 g,胎龄≤34周的早产儿进行研究,其中治疗组31例于生后第5～7天开始予以rhEPO治疗(250 U/kg·次,皮下注射,每周2次),共6周,同时补充铁剂和多种维生素;对照组28例未给予rhEPO和铁剂治疗.比较两组的血液学指标、输血的量和次数.结果组间胎龄、出生体重、生后第1周的血红蛋白(Hb)、抽血的量和次数、并发症、机械通气的天数无差别.每个病人的输血次数和量,rhEFO治疗组为(0.7±1.0)次/人、(8.4±13.4)ml/kg,对照组为1.6±1.2)次/人、(20.8±15.9)ml/kg;两组对比,差异有非常显著性(P＜0.001).治疗组74.19%不需输血,而对照组32.14%不需输血(P＜0.001).两组生后Hb均逐渐下降,但对照组下降较治疗组明显(P＜0.005);最低的Hb均值,治疗组为(98.5±16.1)g/L,对照组为(84.9±19.3)g/L.治疗组网织红细胞于rhEPO治疗1周后即较对照组明显升高(P＜0.001),治疗组第2周达高峰.两组血清铁(SI)生后均呈下降趋势,但治疗组下降较对照组明显(P＜0.001).结论rhEPO预防性治疗早产儿贫血效果显著,可减少VLBW的输血量和次数.     

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.