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121.
This study was performed to evaluate the role of protein kinase C (PKC) activity in the development of chemoresistance in clinical breast cancer cells. To simulate the clinical situation, native tumor cells derived from 10 patients with advanced breast cancer were brought into short-term cultures, and treated with anthracyclines (doxorubicin, mitoxantrone), paclitaxel and combinations, respectively. After 3 days of incubation, we determined total PKC activity relative to each control incubated with blank medium. Furthermore, we determined the chemoresistance against these drugs from each cell population separately. Relative PKC activity ranged from 14 to 249%; 64% (37 of 58) of the breast cancer cell suspensions were considered chemoresistant. There was a non-significant trend to a higher relative PKC activity in resistant cells compared to non-resistant cells (p=0.058), regardless of the antineoplastic agent investigated. The individual variability in both PKC activity and chemoresistance pattern revealed that dysregulated PKC activity mediates resistance to antineoplastics. In order to achieve clinical value, evaluation of more data concerning the PKC signal-transduction pathway is necessary. New protocols of cancer treatment will require this information in order to be successful.  相似文献   
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OBJECTIVE: To evaluate the efficacy of high titer respiratory syncytial virus (RSV) immune globulin (RSVIG) in the treatment of previously healthy children hospitalized with proven RSV lower tract infection (LRI). METHOD: Infants and young children /=2. 5 were enrolled. RESULTS: One hundred and one previously healthy children hospitalized with RSV LRI received either 1500 mg/kg of RSVIG (RespiGam, MedImmune Inc, Gaithersburg, MD) or albumin placebo in a randomized, double-blind, placebo-controlled trial. Forty-six RSVIG and 52 recipients of placebo met all eligibility criteria. Demographic characteristics of the two groups were similar. More RSVIG recipients (46% vs 29%) had an SaO2 /=3.0) had 1.6 fewer hospital days and 2.7 days less ICU stays. CONCLUSION: RSVIG infusions seemed safe and generally well tolerated. Although some beneficial effect trends were seen for those with more severe disease who were treated there was no evidence that treatment with RSVIG resulted in reduced hospitalization and reduced ICU stays in all children with RSV disease.  相似文献   
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We retrospectively reviewed the chart records at the Veterans General Hospital-Taipei for the period between January 1985 and December 1994 to examine the temporal relationship between cancers of the lung and upper aerodigestive tract. A total of 56 patients (54 males, 2 females) with histocytologically proven double primary cancers, with either lung cancer or upper aerodigestive tract cancers appearing first, were found. Squamous cell carcinoma was the most frequent histologic type of lung cancer (squamous 57%, adenocarcinoma 27%, poorly differentiated carcinoma 9%, small cell lung cancer 7%). The incidence of lung cancer patients with upper aerodigestive tract cancer was 0.9% (56/6412). There was no significant difference in the occurrence of upper aerodigestive tract cancer between non-small cell and small cell lung cancer (P > 0.05). However, the incidence of squamous cell lung cancer with upper aerodigestive tract cancer was higher than that of non-squamous cell lung cancer (P < 0.05). With regard to the location of lung cancer, the right lung was more commonly affected than the left (P < 0.001). The locations of upper aerodigestive tract cancers in these lung cancer patients were as follows: larynx 24, nasopharynx 11, esophagus 10, hypopharynx 4, pharyngeal tonsils 2, oral cavity 5. Most upper aerodigestive tract cancers were diagnosed before lung cancer (36/56, 64%), and lung cancer was diagnosed within 3 years in more than half of cases after the diagnosis of upper aerodigestive tract cancer (58.3%). Most lung cancers that preceded upper aerodigestive tract cancer were at an early stage at diagnosis (stage I 4, stage Illa 1), whereas the others, appearing either synchronously or after the diagnosis of upper aerodigestive tract cancer, were mostly at the late stage. There was no difference in survival between lung cancer patients with upper aerodigestive tract cancer and those without (P > 0.05).   相似文献   
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Endovascular grafting of abdominal aortic aneurysms provides a good alternative to open surgery, especially in high‐risk patients. Endoleaks are a well‐recognized complication and are typically diagnosed on CT. We descibe a case in which a patient's endoleak was evaluated by MRI and successfully treated by direct thrombin injection into the site of the leak.  相似文献   
127.
Composite tissue allotransplantation (CTA) constitutes one of the last frontiers of microsurgery. Prior to its clinical application, the long-term efficacy of modern immunotherapy must be tested in a pre-clinical CTA model. Based on the concept of osteomyocutaneous forearm flap, we developed a CTA flap model in swine. After identifying the vascular territory of the flaps in six pigs (vascular casting), flaps were transplanted from mismatched donor to recipient pigs (n = 6). Rejection was assessed daily by visual inspection and histopathology of biopsy specimens. Recipient pigs were able to ambulate immediately following surgery. There were no flap failures owing to technical or surgical complications. Rejection occurred over a period of 7 days as manifested by edema, cellular infiltration, epidermalysis, and thrombosis. This pre-clinical flap model is excellent for evaluating the effectiveness of modern immunotherapy because it is anatomically and immunologically relevant and because the minimal morbidity caused to the animal permits long-term studies.  相似文献   
128.
The enzymatic fundamentals of lipid metabolism of equine have not been thoroughly investigated at this point in time. It is still unclear why ponies in contrast to horses may become hyperlipaemic when coming negative energy balance. In this study, the activities of the triglyceride-cleaving key enzymes of ponies are large bred horses were investigated in order to obtain insight into the aetiology of the syndrome. The objective of the study was to measure the activities of hormone-sensitive lipase (HSL), lipoprotein lipase (LPL) and hepatic triglyceride lipase (HTGL) in ponies and horses in ex vivo in vitro assays. Norepinephrine (NE) stimulated pony adipocytes to release FFA in a linear fashion (4.57 ± 2.09 nmol FFA · 105 cells−1 · min−1). This was not observed in horses. Lipolysis was significantly higher in fat cells of ponies than in horses when adenosine deaminase (ADA) and NE were added (12.71 ± 3.12 vs. 1.96 ± 1.22 nmol FFA · 105 cells−1 · min−1). Relative inhibition of lipolysis by the action of insulin was comparable in adipocytes of horses and ponies. However, absolute FFA release in pony fat cells was as high as the maximal NE and ADA stimulated lipolysis in horse adipocytes. Postheparin plasma lipase activities in ponies and horses did not differ between the sub-species. This finding was supported by the results obtained from measurement of LPL activity in adipose and muscle tissue showing only a tendency of increased activities in pony explants when compared to horse tissue incubations. This study further supports the hypothesis that differences in regulation of TG release from fat stores rather than clearance of TG from plasma is causative for the development of hyperlipaemia in ponies. Abbreviations used: ADA, adenosine deaminase; BW, body weight; FFA, free fatty acid; HSL, hormone-sensitive lipase; HTGL, hepatic triglyceride lipase; LPL, lipoprotein lipase; NE, norepinephrine; SDS, sodium dodecyl sulfate; TG, triglyceride; VLDL, very low density lipoprotein.  相似文献   
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目的:比较采用骨形态发生蛋白人工骨植骨加骨折内固定与自体髂骨植入加骨折内固定治疗骨质疏松性转子间骨折的效果。方法:选择2003-10/2005-10桂林医学院附属医院骨科收治的Ⅲ、Ⅳ、V型骨质疏松性转子间骨折患者51例,均知情同意。实验分组:随机将病例分为2组,骨形态发生蛋白人工骨植入组26例,自体髂骨植入组25例。实验干预:采用股骨上段外侧切口,DHS或加防旋钉内固定,骨形态发生蛋白人工骨由处理后的牛松质骨与成品重组人骨形态发生蛋白2按一定比例复合而成,骨折固定后在骨折缺损处、内侧及骨折周围植骨,骨形态发生蛋白人工骨组采用骨形态发生蛋白人工骨植入,自体髂骨组取自体髂骨植入。实验评估:术后定期随访,比较二组患者的基本情况、临床效果和影像学结果(骨折愈合情况和颈干角的变化)。随访时关节功能评定参照采用黄公怡等提出的标准,分为优、良、可、差4级。髋内翻分类标准为颈干角<100°。结果:术后随访1年,51例患者全部进入结果分析。①术后X射线片观察:骨形态发生蛋白人工骨组临床愈合时间短于自体髂骨组[(94.50±22.45),(116.96±15.90)d,P<0.01];骨形态发生蛋白人工骨组术后1年颈干角大于自体髂骨组[(127.19±3.23)°,(120.4±5.22)°,P<0.01]。②髋关节功能及不良事件和副反应:骨形态发生蛋白人工骨组术后以1年髋关节功能优良率优于自体髂骨组(P<0.05);骨形态发生蛋白人工骨组髋内翻、下肢短缩(>2cm)的发生率均低于自体髂骨组[髋内翻(n):4,7;下肢短缩(n):3,5,P均<0.01];钉退出二组差异均无显著性意义(P>0.05)。结论:伴有骨质疏松的转子间骨折患者,采用骨形态发生蛋白人工骨植骨优于自体髂骨植骨,可缩短骨折愈合期,减少髋内翻等并发症的发生率,提高术后髋关节功能优良率,提示骨形态发生蛋白人工骨能替代自体髂骨植骨治疗骨质疏松性转子间骨折。  相似文献   
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