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21.
Abstract – Oral health was studied in a group of asthmatic children (n = 61). The children were divided in two groups, 5–10 and 11–18 yr of age. The individuals with asthma were further sub grouped with respect to the disease severity. Severe asthma was defined as more than 10 asthmatic attacks per year. This patient group had daily medication compared to children with moderate asthma (<10 asthmatic attacks/yr) who medicated temporarily. 55 age matched children from the same area made up the control group. Ail children were examined clinically and two bitewing radiographs were taken. The results showed no statistically significant differences concerning caries prevalence and gingival condition in asthmatic children compared to a healthy control group. The study shows that neither the asthma per se nor the disease severity affected the caries prevalence and gingival condition in asthmatic children.  相似文献   
22.
Abstract— The effect of growth hormone (GH) treatment on craniofacial development was studied in five children exhibiting growth retardation following bone marrow transplantation. Linear and angular measurements were made on lateral radiographic cephalograms taken prior to the start of GH treatment and after an average treatment time of 1.2 yr. The results showed that the mean growth increments of mandibular length in the GH treated children, exceeded the corresponding values of the control group by 150% during the period of investigation. It is suggested that this dimensional increase in the patients was due to GH stimulation on the chondral growth process in the mandibular condyles.  相似文献   
23.
Abstract— Influence of 5,5-diphenylhydantoin (phenytoin;PHT) on the cytoplasmic free Ca2+ concentration, [Ca2+]i, was studied in fura 2 loaded adherent monolayers of human gingival fibroblasts derived from three patients before and after 9 months of PHT therapy. In the patient where gingival overgrowth developed during PHT medication (responder), addition of PHT to gingival fibroblasts derived before PHT medication induced a transient extracellular Ca2+ dependent increase in [Ca2+]i. In a non-responder patient, where gingival overgrowth did not develop during the same period of PHT therapy, addition of PHT to gingival fibroblasts derived before the start of medication did not significantly affect [Ca2+]i. Under extracellular Ca2+ deficient conditions, addition of PHT to serum-starved fibroblasts derived from the two categories of patients before the medication resulted in an increase in [Ca2+]i. In fibroblasts derived from the responder patient during PHT medication, in contrast to those from the non-responders (n = 2), the basal level of [Ca2+]i was significantly decreased. The results indicate that, in the cases studied, there is a relationship between PHT induced alterations in [Ca2+]i in gingival fibroblasts and the clinical development of gingival overgrowth.  相似文献   
24.
The major potential adverse effect of use of sulfonylurea agents (SUAs) is a hyperinsulinaemic state that causes hypoglycaemia. It may be observed during chronic therapeutic dosing, even with very low doses of a SUA, and especially in older patients. It may also result from accidental or intentional poisoning in both diabetic and nondiabetic patients. The traditional approach to SUA-induced hypoglycaemia includes administration of glucose, and glucagon or diazoxide in those who remain hypoglycaemic despite repeated or continuous glucose supplementation. However, these antidotal approaches are associated with several shortcomings, including further exacerbation of insulin release by glucose and glucagon, leading only to a temporary beneficial effect and later relapse into hypoglycaemia, as well as the adverse effects of both glucagon and diazoxide. Octreotide inhibits the secretion of several neuropeptides, including insulin, and has successfully been used to control life-threatening hypoglycaemia caused by insulinoma or persistent hyperinsulinaemic hypoglycaemia of infancy. Therefore, this agent should in theory also be useful to decrease glucose requirements and the number of hypoglycaemic episodes in patients with SUA-induced hypoglycaemia. This has apparently been confirmed by experimental data, one retrospective study based on chart review, and several anecdotal case reports. There is thus a need for further prospective studies, which should be adequately powered, randomized and controlled, to confirm the probable beneficial effect of octreotide in this setting.  相似文献   
25.
This exploratory study examined the heart rates (HR) and skin temperatures (ST) of 18 preschool children while they viewed two clips of everyday children's television (TV) programming. The measurements were made in a day care setting, in a naturalistic environment designed to mimic the real world of children's TV viewing. The purpose of the study was to determine whether cardiovascular and autonomic arousal to TV programming might occur in some children. Since a large body of psychosocial literature addresses the affects of TV violence on children, HR and ST were examined during exposure to scenes from Mr. Roger's Neighborhood and G.I. Joe cartoons. The Mr. Roger's clip was slow, rhythmic, prosocial, and nonviolent, while the G.I. Joe clip was fast-paced, staccato, colorful, and full of verbal and action violence. The study found a significant effect of exposure to the cartoon violence on HR, with HR increasing. ST decreased, but not significantly, and there was a significant effect of time on the ST, due possibly to habituation. This finding has relevance to nursing assessment, intervention, and education of parents and children, since TV viewing is a pervasive cultural phenomenon. The possibility of excessive or inappropriate autonomic and cardiovascular responsiveness in some children to TV must be considered.  相似文献   
26.
【目的】通过对经住院治疗后下肢深静脉血栓形成(deep venous thrombosis,DVT)患者院外分别继续应用低分子肝素(low molecule weight heparin,LMWH)或维生素K拮抗剂(vitamin K antagonists,VKA)的效益-风险比的对比研究,探讨较为有效、安全、简便的抗凝方案。【方法】将2008年12月-2011年3月符合纳入标准的患者随机分为A组(应用低分子肝素钙)和B组(应用华法林),并随访6个月,期间通过定期监测凝血功能及血小板计数,调整用药方案;每2个月做1次全面随访,包括有无出血、肝素诱导的血小板减少和复发事件的发生。【结果】两组均取得有效的抗凝效果,并且A组副作用发生率在各监测点明显低于B组(P<0.05),随访中发现两组DVT复发率无差异(P>0.05),但随着抗凝时间延长,两组患者出血发生率增加。在DVT复发患者中,髂股深静脉血栓形成者复发率最高,其次是股静脉、腘静脉。患者对应用A治疗方案的依从性较高。【结论】DVT患者院外继续应用LWMH抗凝效果可靠,用药安全性高,副作用较小,操作及监测简单,与应用VKA相比效益-风险比较高。  相似文献   
27.
目的探讨不同类型肾脏占位病变的超声造影特点。方法对照病理诊断结果分析76例肾脏占位病变Sono Vue超声造影特征。结果肾恶性肿瘤62例,良性肿瘤14例。肾恶性肿瘤超声造影剂的充盈和消退呈多样性,以同步增强和快增强多见,造影剂的快速消退和缓慢消退之间无明显差别,差异无统计学意义(P>0.05)。恶性肿瘤典型的表现是整个病灶弥漫增强,轮廓边界清晰,呈"亮球"征(95.2%),并多有假包膜(87.1%)。肾错构瘤表现为无假包膜的不均匀增强,而肾囊肿始终无增强。结论超声造影有助于肾占位病变的鉴别诊断和预后判断。  相似文献   
28.
目的:了解进展较快的食管和贲门癌前病变的时间,为寻找合适的筛查间隔提供线索.方法:在食管癌高发区河北涉县对40~69岁人群开展重复的内镜筛查.结果:301例重复筛查共观察到40例病情发生进展者,其中7例重度不典型增生中:1例首检为正常,间隔13个月检出重度不典型增生,1例首检为基底细胞增生,间隔7个月检出,4例首检为轻度不典型增生,分别间隔3个月、4个月、4个月、10.5个月检出,1例首检为中度不典型增生,间隔12.5个月检出;6例原位癌及黏膜内癌中:1例首检为轻度不典型增生,间隔48个月检出,2例中度不典型增生分别间隔4个月、13个月检出2例,3例重度不典型增生分别间隔3.5个月、9个月、17.5个月检出;3例浸润性癌中:1例中度不典型增生,间隔50个月检出、2例重度不典型增生间隔14个月和19个月检出.结论:食管和贲门癌前病变的滞留时间变异较大,有必要适当缩短筛查间隔,通过及时复查捕获那些进展较快、多点起源和首检遗漏的癌前病变.  相似文献   
29.
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.   相似文献   
30.
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.   相似文献   
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