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51.
The purpose of this study was to analyze the expression of B cell growth factor (BCGF) receptors and to elucidate the biologic effects of biochemically purified natural BCGF at the B cell precursor stage of human B lineage lymphoid differentiation. The specific binding of radioiodinated high-mol-wt BCGF (125I-HMW-BCGF) and low-molecular-wt BCGF (125I-LMW-BCGF) to fresh marrow blasts from B cell precursor acute lymphoblastic leukemia (ALL) patients was initially investigated. The estimated number of radioiodinated BCGF molecules bound per blast ranged from undetectable to 24.3 X 10(3) for HMW-BCGF, and from 11.5 X 10(3) to 457.8 X 10(3) for LMW-BCGF. In 3H-TdR incorporation assays, 75% of cases showed a significant response to LMW-BCGF with a median stimulation index of 9.3. By comparison, only 33% of cases showed a significant response to HMW-BCGF with a median stimulation index of 2.4. Subsequently, B cell precursor colony assays were performed to assess and compare the biologic effects of BCGF on leukemic B lineage lymphoid progenitor cells. Among 28 cases studied, 57% responded to both HMW-BCGF and LMW-BCGF, 21% responded only to LMW-BCGF, and the remaining cases showed no proliferative response to either growth factor. The response patterns of virtually pure populations of FACS- sorted leukemic B cell precursors were essentially identical to the proliferative responses of unsorted leukemic B-cell precursors. Synergistic effects between HMW-BCGF and LMW-BCGF were observed in 80% of the cases that responded to both. The numbers of cell-bound radioiodinated BCGF molecules, the stimulation indices, as well as the number of B cell precursor colonies in BCGF-stimulated cultures showed a marked interpatient variation. Patients with structural chromosomal abnormalities (SCAs) involving 12p11-13 or patients with a Philadelphia chromosome showed a greater HMW-BCGF response at the level of leukemic progenitor cells than did other patients (P = .02). The LMW-BCGF response was significantly greater for patients with SCA than for patients without SCA (P = .04). The response of leukemic progenitor cells to HMW-BCGF or LMW-BCGF did not correlate with sex, age, disease status, FAB morphology, WBC at diagnosis, or immunophenotype. To our knowledge, this study represents the first detailed analyses of BCGF receptor expression and BCGF effects in B cell precursor ALL. The data presented provide direct evidence for the expression of functional receptors for both HMW-BCGF and LMW-BCGF in B cell precursor ALL.  相似文献   
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CJ Greenall  NA Drage 《Ultrasound》2015,23(2):126-129
Sebaceous carcinoma is a rare cutaneous malignancy, commonly affecting the eyelids. This case highlights a patient who presented with sebaceous carcinoma of the right upper lip with extensive involvement of the soft tissues of the head and neck. As part of the initial investigation, ultrasound was requested. This case demonstrates the ultrasound features of sebaceous carcinoma as well as revising the normal ultrasound anatomy of the upper lip and muscles of the cheek.  相似文献   
54.
Periodontal bio‐repositories, which allow banking of clinically validated human data and biological samples, provide an opportunity to derive biomarkers for periodontal diagnosis, prognosis and therapeutic activities which are expected to improve patient management. This article presents the establishing of the Malaysian Periodontal Database and Biobank System (MPDBS) which was initiated in 2011 with the aim to facilitate periodontal research. Partnerships were established with collaborating centres. Policies on specimen access, authorship and acknowledgement policies were agreed upon by all participating centres before the initiation of the periodontal biobank. Ethical approval for the collection of samples and data were obtained from institutional ethics review boards. A broad‐based approach for informed consent was used, which covered areas related to quality of life impacts, genetics and molecular aspects of periodontal disease. Sample collection and processing was performed using a standardized protocol. Biobanking resources such as equipment and freezers were shared with the Malaysian Oral Cancer Database and Tissue Bank System (MOCDTBS). In the development of the MPDBS, challenges that were previously faced by the MOCDTBS were considered. Future challenges in terms of ethical and legal issues will be faced when international collaborations necessitate the transportation of specimens across borders.  相似文献   
55.
目的比较介入封堵与外科手术治疗主动脉窦瘤破裂(RSVA)的疗效及安全性。方法选取RSVA患者22例,介入封堵治疗10例(介入组),外科手术治疗12例(手术组)。术后随访6—24个月,比较两组临床症状、是否存在残余分流、有无瓣膜反流、封堵器有无移位、肺动脉压变化及心功能状态。结果介入组均完全封堵;与术中比较,术后肺动脉收缩压、肺动脉平均压均降低,差异均有统计学意义(P均0.05);术后即刻造影示少量残余分流1例。手术组完全封堵率为91.67%(11/12);术后出现较大的残余分流和严重低心排量综合征各1例。两组随访期内均未发生右心衰竭、栓塞、感染性心内膜炎、主动脉瓣反流、溶血和死亡等。结论介入封堵治疗主动脉窦瘤破裂与外科修补疗效相当,且具有较好的安全性。  相似文献   
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58.

Background and Aims:

Tracheal tubes are commonly used in intensive care unit (ICU) and lead to complications like displacements. The primary aim of the study was to evaluate if the rate of tracheal tube displacement benchmarked at <1% per patient and <0.5% per tracheal tube day, could be sustained over a prolonged period. The secondary aim was to document the patterns of all forms airway accident and to evaluate their consequences.

Subjects and Methods:

This was a prospective observational study of Intubated and ventilated patients in a General Medical-Surgical Adult ICU. The incidence of accidental extubation, self extubation, partial displacement and blockages of tracheal tubes were recorded.

Results:

The overall tracheal tube displacement rate was 61/10,112 (0.6%) per patient and 61/28,464 (0.22%) per tracheal tube day. There were 30 additional incidents of blockage, kinking or biting of the tracheal tube. Physiological consequences-69 were mild, 10 moderate, 12 major and one death. Of the 91 accidents, 30 were partly and 30 were completely preventable. 76 incidents involved an endotracheal tube (54 displaced, 12 blocked and 10 bitten-kinked) and 15 a tracheostomy tube (seven displaced and eight blocked). Accidents were more common in medical than surgical patients (medical = 48, cardiac surgical = 17 and other surgical/trauma = 26).

Conclusion:

Tracheal tube displacement rate in a mixed medical-surgical adult ICU was maintained below the pre-set benchmark of <1% per patient and <0.5% per intubated day over nearly a decade.  相似文献   
59.
目的 分析新疆维吾尔族(维族)IFG人群血脂代谢状况及LDL-C升高的危险因素。 方法 对新疆地区2053例30~80岁维族居民行横断面调查,筛查IFG人群,分析血脂代谢状况及LDL-C相关危险因素。 结果 该IFG人群中,血脂代谢异常的总患病率为99.8%(613/614)。高TG血症患病率为85.5%(525/614),男女比较,差异无统计学意义(P〉0.05);高TC血症、高LDL-C血症患病率为72.5%(445/614)和40.7%(250/614),男性高于女性(75.0% vs 70.1%,52.4% vs 29.9%,P〈0.05);低HDL-C血症患病率为29.8%(183/614),男性低于女性(28.0% vs 31.4%,P〈0.05)。Logistic回归分析显示,LDL-C升高的危险因素为年龄、TC、2 hPG。 结论 维族IFG人群血脂代谢异常的总患病为99.8%,其中LDL-C升高的患病率为40.7%,其危险因素为年龄、TC和2 hPG。  相似文献   
60.
目的:系统评价前哨淋巴结活检(SLNB)预测口腔癌颈淋巴结转移的临床价值。方法:通过计算机检索CENTRAL、Medline、EMBASE、IFCC、中国生物医学文献数据库系统(CBM)、中国期刊全文数据库(CNKI)、中文科技期刊全文数据库(CQVIP)、万方数据库等,收集应用前哨淋巴结活检判断口腔癌颈淋巴转移的诊断试验,应用统计软件Meta-DiSc 1.4进行数据分析。结果:纳入分析的文献9篇,前哨淋巴结活检判断口腔癌颈淋巴转移的敏感度、特异度、阳性似然比(+LR)、阴性似然比(-LR)、诊断优势比(DOR)及系统接收操作特性曲线(SROC)下面积分别为84%(95%CI 73%~92%)、100%(95%CI97%~100%)、19.16(95%CI 7.65~47.77)、0.22(95%CI 0.10~0.51)、97.72(95%CI 29.69~321.61)和0.99。结论:前哨淋巴结活检可作为临床上判断口腔癌颈淋巴结转移有效可行的方法。  相似文献   
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