口服抗癫癎药物治疗儿童热性惊厥的临床与脑电图分析

目的：了解有癫癎高危因素的热性惊厥患儿应用丙戊酸钠与托吡酯口服治疗4年的临床与脑电图改变情况。方法：对2004~2005年的132例有应用抗癫癎药物指征的热性惊厥患儿给予丙戊酸钠与托吡酯口服治疗,每半年随访一次病情变化、血常规和肝肾功能;每一年随访一次睡眠脑电图,共随访4年。结果：随访时间1~10年,丙戊酸钠口服液单药治疗110例,长期控制率为98.2%,95例已停药,10例正处在减药过程中。托吡酯单药治疗13例,均发作控制,顺利停药。无一例出现血常规和肝肾功能异常表现。治疗后睡眠脑电图恢复正常者102例,出现局灶性改变者8 例,两侧同步性棘慢波4例,3 Hz棘慢波及多棘慢波2例。结论：对于癫癎高危因素的热性惊厥患儿,早期使用抗癫癎药物丙戊酸钠或托吡酯,疗效确切,无明显不良反应。抗癫癎药物治疗后大部分患儿睡眠脑电图恢复正常。     

托吡酯治疗小儿癫 66例临床分析

目的观察托吡酯单药或添加治疗治疗小儿癫.方法观察部分性发作及继发性全身性发作17例,Lennox-Gastaut综合征31例,West综合征18例,对其中已应用传统抗癫药物治疗控制不理想的病例添加托吡酯治疗,而对新诊断病例应用托吡酯单一治疗,进行自身对照的开放性研究.结果①托吡酯治疗小儿癫66例,平均疗程6个月,其总的疗效为发作减少≥50%占48例(72.7%),发作减少≥75%占36例(54.5%),发作控制27例(40.9%).②托吡酯治疗部分性发作及继发性全身性发作17例发作减少≥50%为15例(88%),发作减少≥75%为11例(51.6%),发作消失为9例(52.9%);Lennox-Gastaut综合征组31例发作减少≥50%为20例(64.5%),发作减少≥75%为16例(51.6%),发作消失为12例(38.7%);West综合征组18例发作减少≥50%为13例(72%),发作减少≥75%为9例(卯.0%),发作消失为6例(33.3%).③添加托吡酯治疗对卡马西平和丙戊酸钠的添加治疗前后的血浓度没有明显影响.④不良反应嗜睡14例(21.2%)、反应淡漠4例(6.0%)、纳差17例(25.7%)、类暑热症4例(6.0%).结论托吡酯对部分性发作及继发性全身性发作、Lennox-Gastaut综合征和West综合征治疗有效、安全,副作用轻.     

托吡酯治疗小儿癫癎66例临床分析

目的　观察托吡酯单药或添加治疗治疗小儿癫疒间。方法　观察部分性发作及继发性全身性发作 17例 ,Lennox Gastaut综合征 31例 ,West综合征 18例 ,对其中已应用传统抗癫疒间 药物治疗控制不理想的病例添加托吡酯治疗 ,而对新诊断病例应用托吡酯单一治疗 ,进行自身对照的开放性研究。结果　①托吡酯治疗小儿癫疒间6 6例 ,平均疗程 6个月 ,其总的疗效为发作减少≥ 5 0 %占 48例 (72 .7% ) ,发作减少≥ 75 %占 36例 (5 4.5 % ) ,发作控制 2 7例 (40 9% )。②托吡酯治疗部分性发作及继发性全身性发作 17例发作减少≥ 5 0 %为 15例 (88% ) ,发作减少≥ 75 %为 11例 (5 1.6 % ) ,发作消失为 9例 (5 2 .9% ) ;Lennox Gastaut综合征组 31例发作减少≥ 5 0 %为 2 0例(6 4.5 % ) ,发作减少≥ 75 %为 16例 (5 1.6 % ) ,发作消失为 12例 (38.7% ) ;West综合征组 18例发作减少≥ 5 0 %为13例 (72 % ) ,发作减少≥ 75 %为 9例 (5 0 0 % ) ,发作消失为 6例 (33.3% )。③添加托吡酯治疗对卡马西平和丙戊酸钠的添加治疗前后的血浓度没有明显影响。④不良反应 :嗜睡 14例 (2 1.2 % )、反应淡漠 4例 (6 .0 % )、纳差 17例 (2 5 .7% )、类暑热症 4例 (6 .0 % )。结论　托吡酯对部分性发作及继发性全身性发作、Lennox Gasta     

三种抗癫(癎)药物单药首治伴中央-颞区棘波的儿童良性癫(癎)的疗效对比

目的 丙戊酸钠、卡马西平、托吡酯被公认为是目前广谱的抗癫(癎)药物,临床上均可用于治疗伴中央-颞区棘波的儿童良性癫(癎)(BECT).本研究旨在比较这些药物对儿童BECT的治疗效果,筛选临床单药治疗的首选药物.方法 通过84例药物治疗BECT病例(丙戊酸钠31例,卡马西平31例,托吡酯22例)的回顾性分析,从首药治疗失败时间、首治发作控制率、药物不良反应三个方面,对托吡酯、卡马西平、丙戊酸钠的治疗效果进行比较.结果 托吡酯、卡马西平、丙戊酸钠的首药治疗失败时间分别为3.00个月[0.75～12.00]、8.00个月[2.50～32.00]、5.00个月[1.25～11.75],三者差异无显著性(P=0.463).癫(癎)发作控制率托吡酯、卡马西平、丙戊酸钠分别为77.3%、83.9%、74.2%,差异无显著性(X2=1.475,P=0.478).托吡酯有较高的药物不良反应发生率,与丙戊酸钠(X2=8.717,P=0.003)和卡马西平(X2=7.105,P=0.008)相比差异有显著性,丙戊酸钠与卡马西平相比差异无显著性(X2=0.111,P=0.74).结论 托吡酯、卡马西平、丙戊酸钠均可作为儿童BECT单药治疗的首选药物.     

Lennox-Gastaut综合征的临床及脑电特征研究

目的　总结Lennox Gastaut综合征 (LGS)的临床及脑电特征。方法　对 32例LGS住院患儿的临床资料进行分析。结果　起病年龄 11个月至 13 5岁。 32例均有 2种或者 2种以上的癫疒间 发作形式 ,最多者达 5种发作形式 ,以强直发作、不典型失神、肌阵挛发作、失张力发作较常见。有病因可寻者 2 1例。脑电图 17例表现为背景波异常 ,32例均有全导爆发的 1 5～ 2 5Hz慢的棘慢波。睡眠期慢的棘慢波发放增多 ,其中有 4例慢的棘慢波持续发放。 9例在睡眠期有 10～ 12Hz的快节律出现。 2 5例有不同程度的智力损害。 7例用丙戊酸或丙戊酸加氯硝基安定发作控制 ,其余 2 5例用上述两种药物发作不能完全控制。结论　LGS的特点是 :(1)形式多样的癫疒间 发作 ;(2 )脑电图有 1 5～ 2 5Hz慢的棘慢波 ,睡眠期慢的棘慢波增多 ,甚至持续发放 ,部分患儿有 10～ 12Hz的快节律出现 ;(3)多数患儿有智力发育落后 ,对抗癫疒间 药物疗效差。少数患儿智力发育正常 ,无病因可寻 ,对抗癫疒间 药物疗效好 ,可能为特发性。     

丙戊酸和拉莫三嗪治疗儿童失神癫癎的临床研究

目的：评价丙戊酸和拉莫三嗪单药治疗儿童失神癫癎的临床疗效。方法：通过典型临床表现和视频脑电图（过度换气诱发实验阳性）确诊儿童失神癫癎,将患者进行随机开放对照分组研究。分别给予丙戊酸和拉莫三嗪单药治疗,随访1年,观察患者的发作控制情况,脑电图的改善以及不良反应。结果：共有48例入组,45例患者完成观察,其中丙戊酸治疗组23例,拉莫三嗪治疗组22例。丙戊酸组在服药12月时有17例实现无发作,其中15例脑电图无癎样放电。拉莫三嗪组在服药12个月时12例无发作（P＞0.05）,其中6例脑电图无癎样放电（P＜0.05）。所有患者均未见严重不良反应。结论：丙戊酸和拉莫三嗪均为治疗儿童癫癎的安全有效药物;丙戊酸控制癎样放电可能优于拉莫三嗪。［中国当代儿科杂志,2009,11（8）：653-655］     

拉莫三嗪单药治疗儿童癫癎的系统评价

目的 系统评价拉莫三嗪单药治疗儿童癫癎的有效性和安全性。方法 计算机检索PubMed、Cochrane 图书馆、CNKI、VIP、CBM、万方等中英文数据库,获得拉莫三嗪单药治疗儿童癫癎的随机对照试验。应用Cochrane 协作网推荐的方法进行文献筛选,资料提取和文献质量评估,采用RevMan 5.2软件进行Meta分析。结果 共纳入9个RCTs （1016例）。拉莫三嗪的癫癎发作完全控制率明显低于乙琥胺,与卡马西平和丙戊酸钠的差异均无统计学意义。拉莫三嗪的不良反应发生率明显低于卡马西平,与丙戊酸钠和乙琥胺的差异均无统计学意义;3种药物的退出率比较差异无统计学意义。结论 对于传统抗癫癎药物治疗无效、不良反应明显患儿,拉莫三嗪是一种较为理想的替代药物。但仍有待高质量、大样本及较长随访时间的随机对照试验予以证实。     

儿童失神癫240例治疗及预后随访报告:应用改良的1989年儿童失神癫诊断标准

目的总结儿童失神癫(CAE)的治疗和预后,为CAE的合理用药和评价远期预后提供依据。方法对1999年10月至2005年12月北京市3家医院为研究CAE易感基因收集的CAE患儿的治疗用药、疗效及预后进行随访。CAE诊断标准参考1989年国际抗癫联盟(ILAE)提出的癫及癫综合征分类诊断标准,并制定了统一的CAE纳入标准和排除标准。根据CAE的选药原则进行治疗,评估CAE患儿的远期预后。结果3家医院共收集符合ILAECAE诊断标准的患儿339例,其中296例符合本研究制定的CAE纳入标准。296例患儿中有56例患儿因失访未得到远期预后随访结果,有随访结果者240例(81.1%),其中男94例(39.2%),女146例(60.8%)。失神发作起病年龄为3岁3个月至12岁,其中4～8岁174例(72.5%)。39例(16.2%)有热性惊厥史,18例(7.5%)有热性惊厥家族史和(或)癫家族史,5例(2.1%)有失神癫家族史。失神癫发作频率为每日5～50次,其中每日发作10～30次占80%。出现失神持续状态1例。伴全面强直-阵挛发作12例(5.0%)。所有患儿发作期EEG均表现为双侧对称同步的3Hz棘慢波爆发,头颅影像学检查均未见异常。治疗首选丙戊酸234例,其中217例(92.7%)于服药后3d至6个月发作完全控制,15例加用另一种药物(其中氯硝西泮7例、硝西泮4例及拉莫三嗪4例)后发作控制,余2例单用丙戊酸2年后仍有发作,但发作次数明显减少;首选拉莫三嗪4例,其中3例发作控制,1例服药1年发作未控制,改用丙戊酸1周后发作控制。2例首选托吡酯治疗,其中1例发作控制,1例服药5个月效果不明显,改用丙戊酸2个月后发作控制。240例患儿随访时间为2～7年,158例(65.8%)已停用抗癫药物,其中停药1年以上者96例,停药后均无复发;82例尚未停用抗癫药物患儿中,80例发作完全控制2年以上,仅有2例仍有失神发作。随访的240例患儿在校学习成绩为中等及以上者有171例(71.3%)。结论丙戊酸是治疗CAE的首选药物,对绝大多数患儿疗效好。少数用丙戊酸发作未控制者可选用拉莫三嗪或苯二氮类药物。典型CAE患儿远期预后良好。     

Lennox-Gastaut综合征54例

目的探讨Lennox-Gastaut综合征(LGS)的发病因素、临床发作特征、脑电图特点、智力影响程度。方法对诊断为LGS患儿54例的病因、性别、发作年龄、发作形式、脑电图、智力测定等资料进行分析总结。结果本组男36例,女18例;发病年龄1个月~8岁,确诊年龄3个月~11岁;病因包括围生期损伤、脑发育不良等;发作形式以强直伴肌阵挛最多;32例(86%)智力不正常;脑电图均有特征性双侧1.5~2.5次/s的棘慢波发放。6例(11%)用丙戊酸钠或托吡酯单药控制,余病例需要两种以上的抗癫药物联用。结论LGS是主要的儿童难治性癫之一,常需要多种抗癫药物合用,具有多种发作形式和特征性脑电图改变,早期诊断和干预对于该病的预后至关重要。     

儿童失神癫240例治疗及预后随访报告：应用改良的1989年儿童失神癫诊断标准

目的总结儿童失神癫（CAE）的治疗和预后，为CAE的合理用药和评价远期预后提供依据。方法对1999年10月至2005年12月北京市3家医院为研究CAE易感基因收集的CAE患儿的治疗用药、疗效及预后进行随访。CAE诊断标准参考1989年国际抗癫联盟（ILAE）提出的癫及癫综合征分类诊断标准，并制定了统一的CAE纳入标准和排除标准。根据CAE的选药原则进行治疗，评估CAE患儿的远期预后。结果3家医院共收集符合ILAE CAE诊断标准的患儿339例，其中296例符合本研究制定的CAE纳入标准。296例患儿中有56例患儿因失访未得到远期预后随访结果，有随访结果者240例（81.1%），其中男94例（39.2%），女146例（60.8%）。失神发作起病年龄为3岁3个月至12岁，其中4~8岁174例（72.5%）。39例（16.2%）有热性惊厥史，18例（7.5%）有热性惊厥家族史和（或）癫家族史，5例（2.1％）有失神癫家族史。失神癫发作频率为每日5~50次，其中每日发作10~30次占80%。出现失神持续状态1例。伴全面强直12例（5.0%）。所有患儿发作期EEG均表现为双侧对称同步的3 Hz棘慢波爆发，头颅影像学检查均未见异常。治疗首选丙戊酸234例，其中217例（92.7%）于服药后3 d至6 个月发作完全控制，15例加用另一种药物（其中氯硝西泮7例、硝西泮4例及拉莫三嗪4例）后发作控制，余2例单用丙戊酸2年后仍有发作，但发作次数明显减少；首选拉莫三嗪4例，其中3例发作控制，1例服药1年发作未控制，改用丙戊酸1周后发作控制。2例首选托吡酯治疗，其中1例发作控制，1例服药5个月效果不明显，改用丙戊酸2个月后发作控制。240例患儿随访时间为2～7年，158例（65.8%）已停用抗癫药物，其中停药1年以上者96例，停药后均无复发；82例尚未停用抗癫药物患儿中，80例发作完全控制2年以上，仅有2例仍有失神发作。随访的240例患儿在校学习成绩为中等及以上者有171例（71.3％）。结论丙戊酸是治疗CAE的首选药物，对绝大多数患儿疗效好。少数用丙戊酸发作未控制者可选用拉莫三嗪或苯二氮类药物。典型CAE患儿远期预后良好。     

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.