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31.
Biopsies from non-hypertrophic and hypertrophic scars and from normal skin have been studied histochemically for activities of nicotanamide adenine dinucleotide diaphorase, lactate dehydrogenase, acid phosphatase, beta-D glucuronidase and alkaline phosphatase. The activities of all enzymes studied except alkaline phosphatase were found to be increased in hypertrophic scars as compared with non-hypertrophic scars and normal skin.  相似文献   
32.
Smoking habits in psoriasis: a case control study   总被引:2,自引:0,他引:2  
We have examined smoking habits in 108 patients with psoriasis, including some with palmoplantar distribution, and compared the results with matched controls from the community. There was a significant association between psoriasis, current smoking status (OR = 2.7, 95% CI 1.44-5.42, P less than 0.01) and smoking habits prior to the onset of disease (OR = 3.75, 95% CI 1.68-9.47, P less than 0.001). There was also a marked dose-response relationship; the relative risk of psoriasis in those currently smoking more than 20 cigarettes/day was significantly elevated (OR = 5.3, 95% CI 2.1-13.0, P less than 0.001). Separate analysis of patients without palmoplantar distribution of psoriasis showed a significant association with smoking prior to onset of psoriasis (OR = 3.6, 95% CI 1.5-9.8, P less than 0.001). Smoking may play a role in the aetiology of this common skin disorder.  相似文献   
33.
This study compared structured observation with a 24 h pictorial recall of household activities (‘sticker diary’) to measure the prevalence of handwashing with soap (HWWS) in the community. The study was done within a cluster-randomised trial evaluating a handwashing promotion programme in Bihar, India. HWWS at key occasions in mothers and school children was measured by structured observation in 299 households from 32 villages. Sticker diaries recalling common activities, including personal hygiene, were used to measure HWWS in 299 households from a further 20 villages. Sticker diary HWWS prevalence estimates were about 13% points higher than structured observation estimates, but the differences varied by the type of handwashing occasion. This study confirms structured observation as the method of choice for the study of handwashing behaviours. The sticker diary method may be useful in large-scale surveys. Sticker diaries may overestimate HWWS at important occasions, but probably less so than conventional questionnaire tools.  相似文献   
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The transforming growth factor-beta type II receptor (RII) is commonly mutated in colon and gastric cancers with microsatellite instability (MI). We utilized our series of lung cancers with MI and rare alleles of the H-ras1 gene to determine the association between MI and RII mutations and searched the entire RII coding region in 33 lung cancers with MI by polymerase chain reaction-single-strand conformation polymorphism analysis. We found no mutations, and these data support other recent evidence that RII mutations rarely occur except in colon and gastric tumors with MI.   相似文献   
37.
目的:采用藻酸钠自体软骨细胞混合物修复猪的关节软骨缺损,观察近期成骨效应。方法:实验于2004-03/2005-04在中山大学附属第二医院实验中心完成。3个月龄的小型猪8只,取其关节软骨进行细胞原代培养,获取原代细胞后,分别进行免疫组织化学法检测细胞Ⅱ型胶原表达。然后对8只小型猪的32个关节进行动物关节缺损的模型建立,每个关节共造3个人工缺损,选择关节左右随机对照。将已经培养好的软骨细胞与已经配制好并消毒的藻酸钠混合,移植到猪的关节软骨缺损处。每只猪关节内注射3个实验点,1个用藻酸钠/细胞混合液为实验组,1个单纯支架材料为单纯材料对照组,1个缺损做空白对照组,模型中缺损区均为关节负重区,胶原纤维绿色(亮绿复染)。修复所用细胞为自体软骨体外培养后,进行移植修复,采用3代体外培养软骨细胞,均匀混和藻酸钠后,行自体移植。8周后取实验关节进行大体观察、苏木精-伊红染色、Masson染色、免疫组织化学法染色观察及O’driscoll组织学评分。结果:纳入小型猪8只,除其中1例因手术切断伸直肌腱而使猪关节活动障碍,其余均未见手术后关节活动障碍,所有手术无术后感染,无关节内感染,无动物死亡。移植的软骨细胞在藻酸钠载体中生长良好,形成透明软骨。根据O’driscoll组织学评分标准,实验组32个猪关节缺损修复的组织学评分为(20.25±1.64)分,高于单纯材料对照组的(7.46±1.29)分及空白对照组的(6.00±2.09)分。免疫组织化学染色可见修复软骨以表达Ⅱ型胶原为主,无Ⅰ型胶原。结论:藻酸钠复合自体软骨细胞作为软骨移植的替代物是可行的,远期效果还有待进一步研究。  相似文献   
38.
Immunologic Aberrations in the Di Guglielmo Syndrome   总被引:1,自引:0,他引:1  
Immunologic studies were performed in 49 patients with the Di Guglielmosyndrome. Although altered immune reactivity has not been previouslythought to be a feature of myeloproliferative disorders, more than one-third ofthe cases showed immunologic aberrations. The abnormalities encounteredincluded overproduction of antibody protein (hypergammaglobulinemia) andan increased tendency to form rheumatoid factor, LE factor (including onecase with overt systemic lupus), positive serologic tests for syphilis, anderythrocyte autoantibodies and isoantibodies.

Possible pathogenetic mechanisms are considered. The underlying neoplasticprocess might directly involve the immunocytes, resulting in exaggerated andnonspecific responses, or in defective self-recognition and thus in the production of autoantibodies. Alternatively, preexisting but "hidden" antigens mightbe exposed by the proliferative disorder, thus stimulating an antibody response. Finally, and perhaps most likely, antigenic alteration of bone marrowtissue might accompany its neoplastic transformation. Such tissue could berecognized as "not-self" or "foreign" by a qualitatively normal immune system.This would result in the production of abnormal proteins, some of which wouldbe immunologically effective.

Submitted on February 1, 1966 Accepted on March 20, 1966  相似文献   
39.
4-Hydroperoxycyclophosphamide (4-HC), a commonly used marrow-purging agent, is active against many tumors, but is also toxic to normal marrow progenitors. Amifostine (WR-2721) is a sulfhydryl compound with chemoprotectant activity. Preclinical studies using suspensions of bone marrow and breast cancer cells demonstrated that ex vivo treatment with amifostine followed by 4-HC resulted in protection of marrow progenitors, with no compromise in the antitumor effect of 4-HC. This fact stimulated the development of a clinical trial. Bone marrow was harvested from 15 poor-prognosis breast cancer patients and randomly assigned to ex vivo treatment with amifostine followed by 4-HC (amifostine + 4-HC), or treatment with 4-HC alone. High-dose chemotherapy was then administered followed by infusion of the purged autologous bone marrow support (ABMS). Leukocyte engraftment, defined as a white blood cell count > or = 1 x 10(9)/L, was achieved in an average of 26 days for patients whose marrow was purged with amifostine + 4-HC versus 36 days for patients whose marrow was purged with 4-HC alone (P = .032). The average number of platelet transfusions (12 v 29; P = .017) and days of antibiotic therapy (28 v 40; P = .012) were significantly less for patients whose marrow was exposed to amifostine + 4-HC, compared with 4-HC alone. Unpurged backup marrow fractions were infused into three patients whose marrow was purged with 4-HC alone, because of inadequate marrow recovery. None of the patients who received amifostine + 4-HC-purged marrow required a backup marrow fraction. Complete remissions were achieved in 83% of patients with measurable disease, with no difference between the two cohorts. Forty- three percent of patients remained alive and progression-free at a mean of 13 months posttransplant. There was no significant difference in the rate or pattern of relapse for patients whose marrow was purged with amifostine + 4-HC compared with those whose marrow was purged with 4-HC alone. Ex vivo treatment of marrow with amifostine significantly shortens the time to marrow recovery, thereby reducing the risk of myelosuppressive complications in breast cancer patients receiving high- dose chemotherapy and 4-HC-purged ABMS. Since supportive care requirements are also significantly decreased, amifostine may reduce the cost of such therapy.  相似文献   
40.
The characterization of many cytokines involved in the control of hematopoiesis has led to intense investigation into their potential use in ex vivo culture to expand progenitor numbers. We have established the optimum ex vivo culture conditions that allow substantial amplification of transient engrafting murine stem cells and which, simultaneously, augment the ability to sustain serial bone marrow transplantation (BMT). Short-term incubation of unfractionated BM cells in liquid culture with stem cell factor (SCF) and interleukin-11 (IL- 11) produced a 50-fold amplification of clonogenic multipotential progenitors (CFU-A). Following such ex vivo expansion, substantially fewer cells were required to rescue lethally irradiated mice. When transplanted in cell doses above threshold for engraftment, BM cells expanded ex vivo resulted in significantly more rapid hematopoietic recovery. In a serial transplantation model, unmanipulated BM was only able to consistently sustain secondary BMT recipients, but BM expanded ex vivo has sustained quaternary BMT recipients that remain alive and well more than 140 days after 4th degree BMT. These results show augmentation of both short-term recovery posttransplant and the ability to serially transplant marrow by preincubation in culture with SCF and IL-11.  相似文献   
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