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排序方式: 共有366条查询结果,搜索用时 15 毫秒
81.
Lu  L; Broxmeyer  HE; Meyers  PA; Moore  MA; Thaler  HT 《Blood》1983,61(2):250-256
An association has been established between human Ia-like antigenic determinants, expression during DNA synthesis on multipotential (CFU- GEMM) and erythroid (BFU-E) progenitor cells, and the regulatory action of acidic isoferritins in vitro. Treatment of human bone marrow cells with monoclonal anti-Ia (NE1-011) plus complement inhibited colony formation of CFU-GEMM) and BFU-E by 50%-70%. Reduction of colonies was similar whether bone marrow cells were exposed to anti-Ia plus complement, high specific tritiated thymidine (3HTdr), or acidic isoferritins. No further decrease was apparent with 3HTdr or acidic isoferritins after Ia-antigen+ CFU-GEMM or BFU-E were removed, or with anti-Ia plus complement or acidic isoferritins after S-phase CFU-GEMM or BFU-E were removed. Anti-Ia, in the absence of complement, had no effect on colony formation but blocked the inhibition of CFU-GEMM and BFU-E by acidic isoferritins. Demonstration of Ia-antigens on BFU-E and inhibition of BFU-E by acidic isoferritins appeared to require the presence of phytohemmagglutinin leukocyte conditioned medium (PHA-LCM) in the culture medium during the 14-day incubation period. these results implicate Ia-antigen+ cells, acidic isoferritins, and PHA-LCM in the regulation of multipotential and erythroid progenitor cells in vitro.  相似文献   
82.
Melanomas located anywhere below the knee can drain to the popliteal fossa. Sentinel nodes in the popliteal fossa are found in 1-9.6% of cases. The positivity rate in these nodes is 12.5-30%, which is comparable to rates in conventional nodal basins. Formal dissection of the popliteal fossa for a positive sentinel node is indicated. Inguinal dissection based only on the presence of involved popliteal lymph nodes is not warranted.  相似文献   
83.
A small fraction of patients with chronic lymphocytic leukemia/small lymphocytic lymphoma develop Epstein-Barr virus–positive B-cell lymphoproliferative disorders. These Epstein-Barr virus–B-cell lymphoproliferative disorders are thought to be related to immune suppression induced by fludarabine/other chemotherapeutic regimens. As in other immunodeficiency-associated lymphoproliferative disorders, these disorders demonstrate a heterogeneous histological spectrum that ranges from polymorphic to monomorphic to classical Hodgkin lymphoma–like lesions. We report a case of concurrent classical Hodgkin lymphoma and plasmablastic lymphoma in a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma treated with fludarabine. Both classical Hodgkin lymphoma and plasmablastic lymphoma were positive for Epstein-Barr virus-encoded RNA, whereas classical Hodgkin lymphoma was also positive for Epstein-Barr virus- latent membrane protein 1, suggesting a different viral latency. Immunoglobulin gene rearrangement studies demonstrated distinct clones in the plasmablastic lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma. These findings suggest biclonal secondary lymphomas associated with iatrogenic immunodeficiency. Epstein-Barr virus–B-cell lymphoproliferative disorders in the setting of chronic lymphocytic leukemia/small lymphocytic lymphoma, in particular those arising after chemotherapy, should be separated from true Richter's transformation, and be categorized as (iatrogenic) immunodeficiency-associated lymphoproliferative disorder.  相似文献   
84.

Background

In the Netherlands, 30% of subfertile women are overweight or obese, and at present there is no agreement on fertility care for them. Data from observational and small intervention studies suggest that reduction of weight will increase the chances of conception, decrease pregnancy complications and improve perinatal outcome, but this has not been confirmed in randomised controlled trials. This study will assess the cost and effects of a six-months structured lifestyle program aiming at weight reduction followed by conventional fertility care (intervention group) as compared to conventional fertility care only (control group) in overweight and obese subfertile women. We hypothesize that the intervention will decrease the need for fertility treatment, diminish overweight-related pregnancy complications, and will improve perinatal outcome.

Methods/Design

Multicenter randomised controlled trial in subfertile women (age 18-39 year) with a body mass index between 29 and 40 kg/m2. Exclusion criteria are azoospermia, use of donor semen, severe endometriosis, premature ovarian failure, endocrinopathies or pre-existent hypertensive disorders. In the intervention group the aim is a weight loss of at least 5% to10% in a six-month period, to be achieved by the combination of a diet, increase of physical activity and behavioural modification. After six months, in case no conception has been achieved, these patients will start fertility treatment according to the Dutch fertility guidelines. In the control group treatment will be started according to Dutch fertility guidelines, independently of the patient's weight.

Outcome measures and analysis

The primary outcome measure is a healthy singleton born after at least 37 weeks of gestation after vaginal delivery. Secondary outcome parameters including pregnancy outcome and complications, percentage of women needing fertility treatment, clinical and ongoing pregnancy rates, body weight, quality of life and costs. Data will be analysed according to the intention to treat principle, and cost-effectiveness analysis will be performed to compare the costs and health effects in the intervention and control group.

Discussion

The trial will provide evidence for costs and effects of a lifestyle intervention aiming at weight reduction in overweight and obese subfertile women and will offer guidance to clinicians for the treatment of these patients.

Trial registration

Dutch Trial Register NTR1530  相似文献   
85.
Daniel W. Visscher  MD    Niru Padiyar  MD    Dan Long  HT  Pam Tabaczka  BS  MT 《The breast journal》1998,4(6):447-451
Abstract: The growth of invasive breast carcinoma is facilitated by abnormal expression of estrogen receptor (ER), however, the status of ER during disease histogenesis is poorly defined. The extent of ER immunostaining (expressed as percentage of positive cells) was semiquantitated in the invasive (ICA) and corresponding in situ (CIS) components of 50 formalin-fixed, paraffin-embedded breast carcinomas and then compared to staining in normal terminal duct lobular units (TDLU) or hyperplastic lesions (if present) in the same tissue sections. Morphologically normal TDLUs from most cases (61%) exhibited ER staining in 11–30% of epithelial cells; only 10% of the cases had TDLUs demonstrating immunoreactivity in more than 50% of cells. In contrast, 80% of the hyperplastic lesions showed ER staining in more than 30% of epithelial cells, with 44% demonstrating immuoreactivity in more than 50% of epithelial cell nuclei (p = 0.01, chi-square test). Although most in situ carcinomas showed even more extensive ER staining than hyperplasias (>70% of cells were positive in 50% of cases), a significant subset (28%) of CIS exhibited staining in less than 10% of cells (p = 0.002, chi-square test). Invasive carcinomas were less often extensively immunoreactive (i.e., >50% of cells positive) than CIS (32% versus 58% for CIS) and there were five cases (10%) in which the CIS component was ER positive but the invasive component was ER negative. Finally, ER-positive carcinomas were significantly more often accompained by extensive CIS and/or proliferative breast disease (p = 0.007 and 0.003, respectively). The divergent levels of ER expression observed between premalignant, preinvasive, and invasive lesions suggests that inappropriate regulation of hormone receptors may be a factor that promotes early growth or progression in breast neoplasia, and ER-positive breast carcinomas are characterized by a different, possibly lengthier, histogenesis than ER-negative malignancies with a greater frequency of background hyperplastic lesions and a larger preinvasive component.  相似文献   
86.
87.

Objectives

Polyphenols are antibacterial and anti-oxidative natural agents. The present in situ study aimed to investigate the effect of different polyphenolic beverages on initial bacterial adherence to enamel in the oral cavity.

Methods

Initial biofilm formation was performed on bovine enamel specimens mounted buccally on individual upper jaw splints and carried by six subjects. After 1 min of pellicle formation, oral rinses with black tea, green tea, grape juice, Cistus tea or red wine were performed for 10 min. Afterwards the slabs were carried for another 19 or 109 min, respectively. Samples exposed to the oral fluids for 30 and 120 min served as controls. Following intraoral exposure, the slabs were rinsed with saline solution. The amount of adherent bacteria was determined with DAPI-staining (4′,6-diamidino-2-phenylindole) and with fluorescence-in situ hybridization (FISH) of eubacteria and streptococci.

Results

Rinses with all beverages reduced the amount of detectable bacteria. Lowest number of adherent bacteria was found following rinses with red wine, Cistus tea and black tea as measured with DAPI (up to 66% reduction of adherent bacteria vs. controls). Also FISH revealed significant impact of most tested beverages.

Conclusions

Rinses with certain polyphenolic beverages as well as consumption of these foodstuffs may contribute to prevention of biofilm induced diseases in the oral cavity.  相似文献   
88.
目的:对晚期脊髓损伤患者开展嗅鞘细胞再移植治疗,探讨其对神经功能的继续改善效果。方法:①患者男性,27岁,哈萨克斯坦籍,2001年9月20日遭霰弹枪击急诊手术后,双下肢不能运动及感觉消失,尿便失禁,右下肢阵发性钝痛。诊断为陈旧性完全性脊髓损伤(T12),美国脊髓损伤协会标准脊髓功能分级为A级。2002年9月30日第1次行脊髓胚胎嗅鞘细胞移植术,2007年2月5日行第2次脊髓胚胎嗅鞘细胞移植术。治疗方案患者知情同意。②取4个月流产胚胎(孕妇及其家属均知情同意)的嗅球,消化成单个嗅鞘细胞后培养2周,细胞浓度约2×1010L-1。于患者相应脊髓损伤上端(平T11椎体)做1个锁孔,直径约3cm,在脊髓损伤部位与正常脊髓交界处沿中线于无血管区,分两点用4.5号细针共注入100μL(第1次手术)、50μL(第2次手术)嗅鞘细胞悬液,细胞数均为1×106个。第2次移植术前进行供、受体细胞HLA配型,术后口服FK506胶囊2mg,2次/d,共42d。结果:①第1次术后3个月,排尿能控制6h,双足运动功能改善,性功能改善,阴茎勃起功能改善,疼痛减轻。②第2次术后10d,双下肢双足皮肤泌汗功能改善,右下肢疼痛减轻,腹部皮肤感觉稍有好转,针刺觉左侧由术前T10皮节消失好转至T10减退。较第2次移植前椎旁躯体感觉诱发电位有所改善,双侧椎旁电位从T10下降到T12。结论:胚胎嗅鞘细胞二次移植能继续改善晚期脊髓损伤患者的神经功能。但移植的细胞数量、容积、注射点位置等需深入探讨。  相似文献   
89.
ARASH KIMYAI-ASADI  MD    GABRIEL B. AYALA  BS  HT    LEONARD H. GOLDBERG  MD    JUSTIN VUJEVICH  MD    MING H. JIH  MD  PHD 《Dermatologic surgery》2008,34(4):498-500
BACKGROUND Immunohistochemical staining has been used to help detect malignant melanoma on Mohs surgery frozen sections. Previous investigators have developed protocols for reliable MART-1 immunostaining of frozen sections, but these protocols are time-consuming.
OBJECTIVE The objective was to report a rapid 20-minute MART-1 immunostaining protocol for frozen sections.
METHODS The protocol was utilized on 30 melanomas treated with Mohs micrographic surgery.
RESULTS The stain clearly highlighted normal background melanocytes, as well as melanocytic hyperplasia and malignant melanoma.
CONCLUSIONS The 20-minute protocol provides a rapid and reliable method for immunostaining of malignant melanoma. The availability of more rapid immunostaining methods improves efficiency of the Mohs laboratory and significantly reduces patient and physician waiting time.  相似文献   
90.
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