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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.
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
43.
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
44.
45.
Psychometric evaluation of the Taiwan version of the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire. 总被引:2,自引:0,他引:2
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
46.
47.
48.
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
49.
黄芪注射液对刀豆蛋白诱导的小鼠肝脏损伤的保护作用 总被引:5,自引:0,他引:5
目的:观察免疫损伤模型组与实验组小鼠外周血中T细胞亚群的变化情况,探讨黄芪注射液对小鼠肝脏损伤的保护作用。方法实验组小鼠每天腹腔注射黄芪注射液400μl,正常组与模型组小鼠每天给予等剂量的生理盐水。第7天在给药1小时后,模型组与实验组小鼠分别经尾静脉注射刀豆蛋白,正常组小鼠则给予等剂量的生理盐水。8小时后检测各组动物外周血中CD4^+T、CD8^+T细胞以及CD4^+/CD25^+T细胞所占比例,检测血浆转氨酶水平,制备肝脏病理标本,进行HE染色。结果尾静脉注射8小时后,实验组小鼠外周血的CD4^+所占T细胞比例较模型组有所升高(P〈0.05),但仍低于正常组水平(P〉0.05):而CD8^+T细胞的比例则无明显变化(P〉0.05)。实验组ALT、AST水平明显低于模型组(P〈0.05)。实验组汇管区淋巴细胞浸润明显减少。结论黄芪注射液对刀豆蛋白诱导的小鼠肝损伤有确切的保护作用。 相似文献
50.
Background:The findings on the effectiveness of platelet-rich plasma, ozone, and hyaluronic acid in the treatment of osteoarthritis of the knee are controversial, and the existing original studies and meta-analyses are mostly comparisons of a single joint cavity injection method, lacking direct and indirect comparisons of different drugs in the joint cavity. The lack of direct and indirect comparisons of different drugs in the joint cavity makes it difficult to have a clearer and more comprehensive understanding of joint cavity injection methods. In this study, the efficacy of platelet-rich, ozone, sodium hyaluronate, and combined knee cavity injections were compared directly or indirectly using a reticulated meta-analysis in this field, and the efficacy of treatment measures was ranked to provide more comprehensive and reliable evidence-based clinical evidence for the selection of knee cavity injections in osteoarthritis of the knee.Objective:To compare the effects of platelet-rich plasma, ozone, and sodium glassate injection interventions on the efficacy of osteoarthritis of the knee through reticulated Meta-analysis, and to comprehensively compare the clinical effectiveness of platelet-rich plasma, ozone, and sodium glassate injection joint cavity injection for the treatment of osteoarthritis of the knee.Methods:The PubMed, CBM, CNKI, VIP, and Wan-Fang databases were searched for information on the effectiveness of platelet-rich plasma, ozone, and sodium vitrate injection for the comparative treatment of osteoarthritis of the knee, with a search time frame of each database from the date of creation to July 20, 2021. Two investigators independently screened the literature, extracted data according to inclusion and exclusion criteria, and evaluated the quality of the literature in parallel. Statistical analysis was performed using Stata 16.0 software to compare the differences in the efficacy of each treatment measure using the ratio and 95% confidence interval as effect indicators and to rank the efficacy.Results:Thirty-three RCTs with 7003 patients with osteoarthritis of the knee were included, involving 5 therapeutic measures. Meta-analysis showed that the efficacy of platelet-rich plasma injection was superior to both ozone and hyaluronic acid therapies. Hyaluronic acid+ozone and platelet-rich plasma+hyaluronic acid were both superior to ozone and hyaluronic acid monotherapy. The differences in efficacy between hyaluronic acid and ozone compared with platelet-rich plasma were statistically significant, and the differences in efficacy between the 2 combination therapies (platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone) and the 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant. Platelet-rich plasma+hyaluronic acid, hyaluronic acid+ozone compared with 3 monotherapies (platelet-rich plasma, ozone, hyaluronic acid) were statistically significant, except for the difference in efficacy with platelet-rich plasma, which was not statistically significant, indicating that this platelet-rich plasma+hyaluronic acid and Hyaluronic acid+ozone combination therapy was superior to monotherapy. Also, the efficacy of platelet-rich plasma was better than hyaluronic acid and ozone and the difference was statistically significant, indicating that platelet-rich plasma was more effective than ozone and sodium glass in the treatment of osteoarthritis of the knee in monotherapy.Conclusion:It is believed that in the course of clinical practice, hyaluronic acid+ozone or platelet-rich plasma+hyaluronic acid combination therapy or platelet-rich plasma therapy can be preferred for patients with osteoarthritis of the knee. 相似文献