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141.
A molecular genetics-based epidemiological investigation was carried out in 1997 in the territory of North-West Tuscany, central Italy, to calculate incidence and prevalence rates of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). Results were compared with a previous epidemiological study conducted in the same area in 1981, in the pre-dystrophin era. Routine adoption of methods of molecular diagnosis determined an increase in prevalence of BMD from 1.06 x 10(-5) to 2.42 x 10(-5) inhabitants, while cumulative incidence of DMD was markedly decreased from 23.12 x 10(-5) during the period 1965-1976 to 10.71 x 10(-5) male live births during the period 1977 1994. The combined reduction of DMD/BMD diagnostic error rate and familial recurrence could explain these results, providing the bases for a consistent redefinition of dystrophinopathy carrier frequency in the area considered.  相似文献   
142.
Natural and human-caused disasters, violence with weapons, and terrorist acts have touched directly the lives of thousands of families with children in the United States.1 Media coverage of disasters has brought images of floods, hurricanes, and airplane crashes into the living rooms of most American families, with limited censorship for vulnerable young children. Therefore, children may be exposed to disastrous events in ways that previous generations never or rarely experienced. Pediatricians should serve as important resources to the community in preparing for disasters, as well as acting in its behalf during and after such events.  相似文献   
143.
The potential of localized heating as a adjunct to radiation therapy   总被引:1,自引:0,他引:1  
  相似文献   
144.
Lack of clinical significance of "enzyme-only" red cell alloantibodies   总被引:1,自引:0,他引:1  
In a retrospective study on samples from 10,000 recently transfused patients, 35 samples were found to contain an antibody that reacted with ficin-treated red cells but was not demonstrable by low-ionic- strength saline solution and indirect antiglobulin test (LISS-IAT). In those 35 patients, the specificity of the antibody was such that each patient would have been transfused with antigen-negative blood had the antibody reacted in LISS-IAT. Tests on red cells from the units already transfused showed that 19 patients had among them received, by chance, 32 antigen-positive and 74 antigen-negative units. The remaining 16 patients had among them received 57 units that were, again by chance, all antigen negative. One patient given antigen-positive blood suffered a delayed transfusion reaction; in two others the antibodies became LISS-IAT active after transfusion. However, similar changes to the LISS- IAT-active state were seen with two antibodies of patients given only antigen-negative blood. Also found in the 10,000 patients were 28 clinically insignificant antibodies, 77 sera in which the antibody was too weak to identify, and 216 autoantibodies that reacted only with ficin-treated red cells. These data support a belief, generally held in the United States but not necessarily elsewhere, that the use of protease-treated red cells for routine pretransfusion tests creates far more work than the accrued benefits justify.  相似文献   
145.
146.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
147.
A substudy of a phase I/II, prospective, multicenter clinical trial was carried out to investigate the potential benefit of therapeutic vaccination on hepatitis B e antigen-negative patients with chronic hepatitis B (CHB), treated efficiently with analogues. Patients were randomized in 2 arms, one receiving a hepatitis B virus (HBV) envelope DNA vaccine, and one without vaccination. At baseline, HBV-specific interferon (IFN)-γ–producing T cells were detected in both groups after in vitro expansion of peripheral blood mononuclear cells. Vaccine-specific responses remained stable in the vaccine group, whereas in the control group the percentage of patients with HBV-specific IFN-γ–producing T cells decreased over time. The vaccine-specific cytokine-producing T cells were mostly polyfunctional CD4+ T cells, and the proportion of triple cytokine-producer T cells was boosted after DNA injections. However, these T-cell responses did not impact on HBV reactivation after stopping analogue treatment. Importantly, before cessation of treatment serum hepatitis B surface antigen (HBsAg) titers were significantly associated with DNA or HBsAg clearance. Therapeutic vaccination in CHB patients with persistent suppression of HBV replication led to the persistence of T-cell responses, but further improvements should be searched for to control infection after treatment discontinuation.  相似文献   
148.
汉语阅读障碍儿童在本顿视觉保持测验中的反应特征   总被引:1,自引:0,他引:1  
目的:比较阅读障碍儿童与正常儿童在本顿视觉保持测验中的反应特征,探索阅读障碍儿童视觉空间记忆能力的特点。方法:①2005-07/2006-05在儿童发育行为门诊遴选阅读障碍儿童20名(平均年龄10.2岁),按1∶1配对原则,选择年龄、性别、年级和家庭状况等条件与阅读障碍组相似的20名正常阅读能力儿童为对照组(平均年龄10.1岁)。②应用国内修订版本顿视觉保持测验C式B法,D式C法和E式D法对两组儿童进行个别测试。C式图卡呈现5s后让被试默画(视觉记忆能力),D式图卡让被试临摹(视觉结构能力),E式图卡呈现10s后间隔15s再让被试默画(视觉延迟记忆能力)。③对两组儿童的视觉记忆保持能力、视觉结构能力和延迟记忆能力进行测试,分别记录两组儿童测验的正确分(每一图卡根据全或无的原则记1或0分,总分0~10)及错误次数(错误类型分为遗漏或增加、变形、持续、旋转、位置错误和大小错误6个范畴),进行配对t检验。结果:40名受试者均进入结果分析。①正确得分:在视觉记忆和视觉结构能力测验中阅读障碍组低于对照组(5.00±2.45,6.60±1.82,P=0.019;7.50±2.44,8.95±1.32,P=0.015),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.077)。②总错误分:在视觉记忆和视觉结构能力测验中阅读障碍组高于对照组(7.65±4.20,4.90±3.24,P=0.016;3.20±3.93,1.15±1.46,P=0.035),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.389)。③错误类型:阅读障碍组儿童在视觉记忆能力测试中变形和持续性错误次数均显著多于对照组(3.95±2.40,1.75±1.52;0.35±0.67,0;P均<0.05),在视觉结构能力测试中变形错误次数显著多于对照组(1.35±1.69,0.35±0.75,P<0.05)。结论:阅读障碍儿童的视觉空间短时记忆能力、视觉结构和视觉运动整合能力存在缺陷。  相似文献   
149.
PURPOSE: The integrin-targeted conditionally replicating adenovirus Ad5-delta 24RGD has been shown to possess strong oncolytic activity in experimental tumors and is currently being developed toward phase I clinical evaluation for ovarian cancer and malignant glioma. Previously, we reported that combination therapy of Ad5-delta 24RGD with irradiation led to synergistic antitumor activity in s.c. glioma xenografts. In the current study, the underlying mechanism of action to this synergy was studied and the effects of combined therapy were assessed in an orthotopic glioma model. EXPERIMENTAL DESIGN AND RESULTS: Sequencing studies in U-87 monolayers showed that delivery of irradiation before Ad5-delta 24RGD infection led to a greater oncolytic effect than simultaneous delivery or infection before irradiation. This effect was not due to enhanced virus production or release. Experiments using a luciferase-encoding vector revealed a small increase in transgene expression in irradiated cells. In tumor spheroids, combination therapy was more effective than Ad5-delta 24RGD or irradiation alone. Staining of spheroid sections showed improved penetration of virus to the core of irradiated spheroids. Mice bearing intracranial tumors received a combination of Ad5-delta 24RGD with 1 x 5 Gy total body irradiation or with 2 x 6 Gy whole brain irradiation. In contrast to the in vitro data and reported results in s.c. tumors, addition of radiotherapy did not significantly enhance the antitumor effect of Ad5-delta 24RGD. CONCLUSIONS: Combined treatment with Ad5-delta 24RGD and irradiation shows enhanced antitumor activity in vitro and in s.c. tumors, but not in an orthotopic glioma model. These differential results underscore the significance of the selected tumor model in assessing the effects of combination therapies with oncolytic adenoviruses.  相似文献   
150.
3H-1,2-二氢-1-吡里酮衍生物的合成   总被引:8,自引:0,他引:8  
发现3 H-1,2-二氢-1-吡咯里嗪酮具有明显的抗炎镇痛作用。用Friedel-Crafts酰化和Dieckmann缩合等反应制备了该酮的一些衍生物,其中五个未见于文献报道。药理实验证明,这些化合物均有不同程度的抗炎镇痛作用。  相似文献   
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