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101.
近年来调节T细胞(Treg细胞)成为免疫学研究的热点问题。这些研究大部分集中于自身免疫病、移植免疫及抗肿瘤免疫领域,对于调节T细胞在针对抗感染免疫反应中作用的认识仍然有限。本文总结了目前在各种类型感染性疾病研究中对Treg的认识,并讨论了其在感染过程中可能发挥的作用。  相似文献   
102.
大中学生预防艾滋病生活技能需求   总被引:4,自引:3,他引:1  
目的了解我国学生对学校预防艾滋病教育中生活技能的需求情况,为今后开展以生活技能为基础的预防艾滋病教育提供依据。方法对北京市5所初中3、所高中和2所大学的1207名学生进行问卷调查。结果无论初中、高中还是大学生,多数学生都认为这些生活技能要素在开展预防艾滋病教育中能够起到重要的作用。不同学段学生对9类技能的认知重要程度不同,初中生认为认识和解决问题能力最重要,高中生认为创造性思维能力最重要,大学生认为批判性思维能力最重要。结论根据学生年龄有所侧重地开展以生活技能为基础的学校预防艾滋病教育十分重要。  相似文献   
103.
A case of beta-thalassemia with an unusual focus of extramedullary hematopoiesis is reported. The presacral area was involved producing a significant mass effect on the rectum.  相似文献   
104.
目的:评价改良去带盲结肠可控膀胱术的临床价值。方法:对8例膀胱癌患者施行全膀胱切除和改良去带盲结肠可控膀胱术。结果:随访3-41个月,均获得良好的疗效。贮尿囊容量为260-700ml,贮尿囊内最大压力为0.981-2.940kPa,每3-6h导尿1次,血清电解质和肾功能正常。结论:本术式可以获得大容量、低内压的贮尿囊,具有可控效果好、操作简单和并发症少等优点。  相似文献   
105.
Golf is an activity generally stressful to the hands and wrists and particularly can produce increasing symptoms in players with underlying problems such as hand and wrist arthritis or tendinitis. The purpose of this study was to quantitate wrist motion and club head/ball impact force in subjects with pathologic conditions of the hand, wrist, or forearm, within a laboratory environment. A regular straight-handled golf club was compared to a new BioCurve handle design that has a 19 degrees ulnar bend. We measured and compared the effect of the two grips on wrist motion, club head velocity, ball impact force, ball impact location, and isometric torsional strength in 20 subjects who had a variety of upper extremity disorders. This data was then compared to data collected in an identical fashion from golfers without such conditions. The results of our study show that there were no differences related to club handle design on impact force or impact location, club head velocity, or club head path and face angle. Wrist kinematic differences were minimal between handle designs. The differences that were significant (P less than 0.05) centered around the decreased ulnar deviation of the left hand that resulted when subjects used the BioCurve handle design, which also allowed greater resistance to torque than the straight grip club. In addition to collecting objective data, we asked subjects for their opinions of the two grips. As a whole, the normal group and the group with pathologic conditions noted more comfort, improved grip, and less shock transmission with the BioCurve handle.  相似文献   
106.
Forty of the 87 patients with microinvasive carcinoma (MIC) of the uterine cervix who underwent surgery were diagnosed colposcopically and the results were compared with the cytological and histological diagnoses. The cytology showed preinvasive carcinoma in 20 (50.0%) patients and invasive carcinoma in 19 (47.5%) patients. A correct colposcopic diagnosis was made in nine (22.5%) patients as having microinvasive carcinoma, 21 (52.5%) patients preinvasive carcinoma and eight (20%) patients invasive carcinoma, to sum up accuracy rate as 32.1%. The abnormalities most commonly observed in colposcopy were mosaic, punctuation and white epithelium. In microinvasive carcinoma, the triad co-existed in 43% of the patients. Atypical vessels, characteristic of invasion, were found in only one third of the patients. Microinvasion, therefore, may not be evident on colposcopy alone. It is therefore necessary to apply cone biopsy, prior to definite therapy, to make an accurate assessment of the maximum depth and extent of the invasion prior to definitive therapy.  相似文献   
107.
本文选择汉正街作个体户人群特需医疗卫生服务需求的典型调查。遁过432例分析及与调查人群平均需求率比较,揭示出个体户人群疾病频率低、文化层次低、自费医疗多的卫生现状,以及个体户人群的特需需求率较低和倾向预防性特需服务的需求特征。本文较多地讨论了个体户人群卫生现状、卫生需求的特性及共性,较深地思考了对个体户人群开展特需服务的策略。并结合医学社会化的大趋势理论,指出特需服务的可行和必行。  相似文献   
108.
Anti-idiotypic antibodies are powerful reagents for the study of immunoregulation, and have potential interest as vaccines against tumors and infectious diseases. Three immunization strategies for the production of rat monoclonal anti-idiotope antibodies have been compared in this paper. Male Wistar rats were immunized i.p. and at multiple subcutaneous sites with 750 micrograms of purified monoclonal antibody against Plasmodium falciparum for three times and subsequently boosted by (1) intraperitoneal injection with 750 micrograms of the immunogen, (2) intravenous inoculation with 400 micrograms of the IgG, and (3) intrasplenic immunization with 200 micrograms of the idiotype. With the intraperitoneal boost method, the frequency of hybrids with anti-idiotope activity was 0.3-0.9% with 62.8-85.2% of the seeded wells containing hybrids. In the intravenous boost group, the percentage of hybrids demonstrating anti-idiotope activity increased to 11.0-13.3% with 80.2-97.9% of the hybrid efficiency. When immunized by the intrasplenic boost route, the frequency of anti-idiotope hybrids generated rose to 12.9-16.4% with 82.3-96.6% of the hybrid efficiency. There was no obvious effect of the boost immunizing methods on the generation of rat monoclonal anti-mouse IgG antibodies. These results indicated that the multiple-site immunization followed by intravenous or intrasplenic boost injection was an appropriate immunizing method for the production of monoclonal anti-idiotope antibodies.  相似文献   
109.
The reconstruction of large bone and joint defects after the resection of malignant tumors remains a major challenge. Chemotherapy has significantly lowered the risk of metastasic disease, but complications associated with reconstructive techniques continue to result in late morbidity. In the present study, biomechanical torsion testing, gait analysis, and histomorphometric and scanning electron microscopic evaluations of 24 dogs were used to examine the effects of preoperative and postoperative administration of cisplatin on the biologic fixation of a porous-coated segmental replacement prosthesis. The chemotherapy consisted of four cycles of cisplatin administered at a dosage of 75 mg/m:2 preoperatively or postoperatively. The healing was enhanced by use of an autogenous corticocancellous bone graft. The graft was placed evenly around the prosthesis and the adjacent femoral cortex. Mechanical analyses of torsional stiffness, yield strength, and maximum strength revealed no statistically significant differences between the groups at 12 weeks. Such lack of difference was mainly due to the penetration of highly organized fibrous tissue into the porous surface; this provided strong fixation of the implant to bone even in the absence of bone ingrowth. Although bone ingrowth into the prostheses was not affected, electron microscopic, histomorphometric, and radiologic analyses showed a clear difference in the formation of new bone around the prosthesis. Preoperative chemotherapy did not alter the formation of new bone, but specimens from animals treated postoperatively with cisplatin showed significantly less bone graft resorption and less new bone formation. Hence, the effect of cisplatin administration caused only a temporary delay, not a permanent effect, on extracortical capsule formation. The formation of extracortical bone and soft tissue might prevent debris-incised osteolysis and, therefore, prevent late complications by forming a tight capsule around the bone-prosthetic interface.  相似文献   
110.
Reoperative Thyroid Surgery   总被引:4,自引:0,他引:4  
Reoperative thyroid surgery is an uncommon operation associated with a high complication rate. We retrospectively reviewed the data of 115 patients to study the incidence of complications after reoperative thyroid surgery. There were 107 women and 8 men (13.4:1.0) with an average age of 42.8 years (range 18–80 years). The most frequent indication for reoperation was completion thyroidectomy for a carcinoma identified by permanent sections (50 patients, 43.5%). Reoperative surgery was performed on 13 (11.3%) patients with recurrent thyroid cancer. The remaining 52 patients underwent reoperation for recurrent thyrotoxicosis (12 patients, 10.4%), recurrent nodular goiter (28 patients, 24.3%) or recurrent multinodular goiter (12 patients, 10.4%). Seven patients with recurrent nodular goiter and one patient with recurrent thyrotoxicosis underwent total thyroidectomy for the presence of malignancies that were identified by frozen sections. Overall, the interval between the initial and reoperative procedures ranged from 1 day to 33 years (2335 ± 272 days). The length of hospital stay was 5.8 ± 0.5 days. The length of time needed for reoperative thyroid surgery was 122.0 ± 6.2 minutes. There was no 30-day perioperative mortality. The postoperative complications consisted of transient hypoparathyroidism in six patients (5.2%), permanent hypoparathyroidism in two patients (1.7%), transient RLN palsy in 3 patients (2.6%), and permanent recurrent laryngeal nerve palsy in two patients (1.7%). Reoperative thyroid surgery can be performed safely with little morbidity to the patient.  相似文献   
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