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41.
Idiopathic thrombocytopenic purpura (ITP), caused by autoantibodies directed against certain platelet antigens, is the most common entity of the immune thrombocytopenias. ITP is an acquired disorder and can affect both children and adults. However, the clinical syndromes of ITP are distinct between children and adults. Childhood (acute) ITP characteristically is acute in onset, occurs within 1-2 weeks of an infection, usually of viral origin, resolves spontaneously within 6 months. Adult (chronic) ITP has an insidious onset and rarely resolves spontaneously. Over the last decade considerable new information has accumulated as to the pathophysiological mechanisms of immune thrombocytopenias. In addition, most of the knowledge on this disorder has been obtained from studies of adult patients with chronic ITP. The present work gives an updated overview of the platelet autoantigens and the molecular immunological reactions in ITP.  相似文献   
42.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants.  相似文献   
43.
Recent molecular cytogenetic studies have elucidated the origin and nature of extra structurally abnormal chromosomes (ESACs) or small supernumerary chromosomes, which are often associated with developmental delay and malformations. We studied the prevalence of inv dup(15) in a nationwide screening programme for mentally retarded children in Taiwan and tried to correlate the genotype and phenotype in those patients. Fluorescence in situ hybridization (FISH) analysis using D15Z, D15Z1, and the cosmids from the Prader-Willi/Angelman syndrome chromosome region (PW/ASCR) was performed on 54 patients (0.45%) with ESACs from 11893 probands within a 5-year period. Of them, inv dup(15) was confirmed in 25 children (46.3%) by FISH analysis. The PW/ASCR probes were used to clarify the size and DNA composition of the markers. Patients with inv dup(15) chromosomes, containing only the heterochromatin or little euchromatin of the proximal 15q (i.e., pter→q11:q11→pter) may have a rather mild or nearly normal phenotype (group 1). Only one patient had some features suggestive of Angelman syndrome, but was considered to be a result of deleted (15)(q12) in the chromosome 15 homologue. Additional copies within D15S11 through GABRB3 (15q11.2-13) resulted in an abnormal phenotype which involved mental and developmental delay but was different from the classical phenotype of PW/AS (groups 2, 3). Signs of autistic behavior did occur in each group. FISH combined with microsatellite analyses showed that the marker was often of maternal origin in de novo cases (n = 12, 86%), or inherited from the mother in only one familial case. Down-inv dup(15) was mentioned in two cases. Unusual features including diaphragmatic eventration, hyperlaxity of joints, arachnodactyly, brain atrophy, epilepsy (particularly infantile spasm), ataxia, genital abnormalities, and cleft lip/palate were noted in those patients. This observation expands the range of phenotypic expression associated with this relatively common ESAC. Conclusion Marked phenotypic diversities exist in children with inv dup(15), dependent upon the size or genetic composition of the markers, degree of mosaicism, parental origin and familial occurrence or not. Patients with a larger inv dup(15) marker chromosome including the PW/ASCR may have a higher risk of abnormalities, but not the typical Prade-Willi/Angelman syndrome phenotype. Received: 11 February 1997 and in revised form: 20 May 1997 / Accepted: 20 May 1997  相似文献   
44.
p53 mutation is commonly associated with high-grade, high-stage human urothelial carcinomas. Recent studies suggest that p53 mutation in low- grade, low-stage bladder carcinomas may be correlated with the progression of the disease. In the present study, we used antisense RNA methodology in vitro to evaluate the significance of the loss of p53 function at an early stage of urinary bladder carcinogenesis. An immortalized nontumorigenic rat urothelial cell line (MYP3) that strongly expresses wild-type (WT) p53 was transfected with a plasmid (pcDL-SR alpha-296) containing a rat WT p53 cDNA in antisense orientation. The transfection resulted in a significant reduction in p53 mRNA expression and protein synthesis, in stimulation of anchorage- dependent growth, and in acquisition of anchorage-independent growth potential. Three such clones, when tested in athymic nude mice, all formed muscle-invasive, high-grade transitional cell carcinomas at s.c. injection sites. When cells were inoculated into an orthotopic site (urinary bladder), one of two antisense transfectants tested formed bulky tumors in the bladder in all seven nude mice and metastases to lungs in three of the seven mice. Analysis of these cells revealed a decrease in the expression of p21 (WAF1, sdi1, or CIP1) and retinoblastoma (Rb) gene product. Phosphorylation of Rb protein was not inhibited when the cells were starved. No significant difference was observed in the expression of p16 protein. In cell cycle analysis, all antisense transfectants tested escaped from G1 arrest by starvation. Furthermore, secretion of interleukin (IL)-6 into culture medium was increased significantly. Treatment with anti-IL-6 antibody suppressed anchorage-dependent growth. This study directly demonstrates that the loss of p53 function at an early stage of urothelial carcinogenesis may result in acquisition of a malignant phenotype by regulating IL-6 production as well as cell cycle related genes.   相似文献   
45.
Y Sun  S Hou  G Xue 《中国中药杂志》1998,23(9):539-41, 576
OBJECTIVE: Based on a study of Concha Ostreae, to provide some reference for the rational approach to leaching mineral drugs. METHOD: Taking the change rates of compatible leaching and value of A as targets, the compatible leaching effect of Concha Ostreae with Radix et Rhizoma Rhei Praeparata, Radix Scutellariae, Pollen Typhae and Fructus Aurantii lmmaturus was studied. RESULT: If Concha Ostreae and the above cited medicinal herbs are decocted together, the yield of extract may be reduced to a certain extent, but the target composition of Radix et Rhizoma Rhei Praeparata and Fructus Aurantii lmmaturus remains intact, only the content of Radix Scutellariae baicalin may be influenced. CONCLUSION: The relationship of technology with preparation must be taken into consideration when making choice of the proper way to leach Concha Ostreae.  相似文献   
46.
目的:探讨重睑形成术的手术方法和效果。方法:对15例(29眼)单睑者在皮下埋藏缝线法重睑形成的基本原理的基础上,在具体操作技术上用我们改良后的手术方法施行手术。结果:经5~10d和6~12mo的随访观察,除其中1例无力型因年龄大适应症选择不当0.5a后效果不佳;其余全部受术者,恢复后形成重睑皱褶自然,长短基本一致,重睑对称。受术者、施术者、第三者均较满意。结论:改良后的重睑形成术,手术操作简便,效果可靠。是一种具有应用价值的手术方式,值得推广使用。  相似文献   
47.
BACKGROUND AND PURPOSE: To adapt the Taiwan version of the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire and evaluate its psychometric properties. METHODS: The DASH questionnaire was adapted through the process of translation, back-translation, and expert review. Eighty two subjects with upper extremity disorders were recruited in a medical center and 46 of these patients could be followed up to assess retest reliability in less than 10 days. Cronbach alpha and intraclass correlation coefficient were used to evaluate the internal consistency and test-retest reliability. Principal axis factor analysis was performed to assess the factor-construct validity, while concurrent validity was tested with the Medical Outcomes Study Short Form-36 (SF-36) Taiwan version questionnaire. RESULTS: The internal consistency of the Taiwan version of the DASH questionnaire was high (Cronbach alpha = 0.96) and the test-retest reliability was satisfactory (intraclass correlation coefficient = 0.9). Principal axis factor analysis confirmed the 1-factor model. The Pearson correlation coefficients of the DASH questionnaire to the SF-36 showed a correlation with physical component summary scores rather than mental component summary scores. Bodily pain, physical function and role-physical scores among the SF-36 subscales were most significantly correlated with DASH disability/symptom scores. CONCLUSION: The Taiwan version of the DASH questionnaire is a valid and reliable measure of health status for patients with upper-extremity disorders.  相似文献   
48.
关于主诉定义和书写要点的讨论   总被引:4,自引:1,他引:4  
文章提出了在医院医疗服务范围和项目不断拓宽的情况下,现行病历书写规章制度中有关“主诉”的定义和书写要求也应进一步修改和拓宽。作者根据多年做临床质量控制工作和住院病历检查的经验,结合国内医学文献中部分专家的意见,对主诉的书写要点和常见问题进行了分析、总结。  相似文献   
49.
根据对13所解剖学实验室的调查,阐述解剖学实验室存在的三大问题,并提出解决问题的对策。  相似文献   
50.
Keratoconjunctivitis sicca (KCS) is a common complication of graft-versus-host disease (GVHD), and may lead to corneal epithelial defect and melting. In contrast, recurrent corneal calcareous degeneration and perforation is rare. A 46-year-old woman developed chronic GVHD after bone marrow transplantation for aplastic anemia. Severe KCS with corneal melting and calcium deposits were noted in the left eye. Penetrating keratoplasty was performed because of corneal perforation, but poor re-epithelialization and calcium deposition recurred. Lamellar keratectomy and amniotic membrane transplantation (AMT) were performed, but acute calcareous degeneration developed with subsequent recurrence of corneal perforation. After regraft, AMT and tarsorrhaphy, the corneal graft remained clear for 3 months. However, breakdown of the corneal epithelium occurred 3 weeks after spontaneous separation of tarsorrhaphy. Six months later, corneal perforation recurred again along with exacerbation of GVHD. Regraft was performed, but the patient refused tarsorrhaphy and AMT. Poor re-epithelialization persisted after regraft. Corneal melting with impending corneal perforation ensued. Further corneal surgery was refused and the patient chose to undergo evisceration. This case demonstrates that the ocular complications of GVHD may be severe enough to lead to corneal perforation and calcareous degeneration that is recalcitrant to medical and surgical treatment.  相似文献   
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