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41.
We report a clinical study of toxicity and pharmacokinetics of intravenously administered natural interferon-gamma. Twenty three cases with metastatic cancer were given interferon-gamma at doses of 10 X 10(4)-400 X 10(4) IU in single injection. Another twenty three cases were administered at doses of 5 X 10(4)-50 X 10(4) IU/day every day for thirty days. Side effects associated with natural interferon-gamma administration were qualitatively similar to those previously reported for alpha, and beta interferon treatment. After intravenous injection, interferon-gamma was cleared monoexponentially with a short half-life of 120 minutes from the circulation. One case with disseminated thyroid cancer showed minor response.  相似文献   
42.
The major heat shock protein, HSP70, protects cells from a variety of stressful stimuli, while c-myc protein allegedly stimulates the expression of HSP70 by transacting on the HSP70 promotor. The present study was aimed at correlating the expression of HSP70 with that of c-myc protein in benign and malignant breast lesions. Indirect immunoperoxidase and immunoblotting techniques using monoclonal antibodies were employed. Fresh frozen sections were prepared from five fibroadenomas and 59 breast carcinomas. Immunohistochemically, both substances were localized in the nuclei and/or cytoplasm of normal and neoplastic epithelial cells. The stromal cells were positive for c-myc protein but negative for HSP70. The expressions of HSP70 and c-myc protein were comparable to each other in the malignant cells from 37 (63%) carcinomas. In 17 (29%) carcinomas, c-myc protein expression predominated over that of HSP70, whereas in five (8%) carcinomas, HSP70 was predominant. Carcinomas with high-grade nuclear atypia often showed negative HSP70 staining, whereas tumors with nuclear HSP70 localization tended to accompany lower-grade nuclear atypia. A similar relation was also observed between c-myc protein expression and nuclear atypia of the tumor. All five fibroadenomas and most of the non-neoplastic epithelial cells adjacent to cancer showed strong reactivities with both substances. Immunoblot analysis for HSP70 revealed a clear, single band in the extract of tumors with strong HSP70 staining, but no, or only faint, bands were seen in the extract of immunohistochemically HSP70-negative carcinomas. The discrepancy between the expressions of each substance in a certain percentage of breast carcinomas may suggest the presence of HSP70 production mechanisms other than the c-myc protein-triggered promotor pathway.  相似文献   
43.

Background

Management of high-grade T1 (formerly T1G3) bladder cancer continues to be controversial. Should patients with T1G3 bladder cancer have an immediate radical cystectomy or should they receive intravesical bacillus Calmette-Guérin preserving bladder? Gemcitabine and cisplatin (GC) adjuvant chemotherapy may help to strike a balance between intravesical and early cystectomy. For purposes of this study, we continue to refer high-grade T1 lesion as “T1G3.”

Objective

To evaluate the characteristics and the long-term outcome of GC adjuvant chemotherapy in T1G3 bladder cancer after transurethral resection of bladder tumor (TURBT).

Materials and methods

We, retrospectively, reviewed 48 patients who were newly diagnosed with T1G3 bladder cancer between January 2009 and December 2012. A total of 48 patients received 4 cycles of GC adjuvant chemotherapy after TURBT. One month after 4 cycles of GC adjuvant chemotherapy, response was evaluated by re-TURBT. Median follow-up was 59.5 (range: 18–70) months, all patients have been observed for more than 3 years. Salvage cystectomy was recommended for patients with persistent disease and for tumor progression after initial complete response.

Result

Complete response was achieved in 44 (91.7%) patients. Of complete responders, 5 patients experienced recurrence and 5 patients showed progression. The progression rate and disease-specific survival rate were 10.4% and 91.7% at 3 years, respectively. More than 80% of survivors preserved their bladder. Kaplan-Meier curves showed that concomitant carcinoma in situ (CIS) was the only factor that had an influence on progression-free survival (P = 0.022) and disease-specific survival (P = 0.017). Concomitant CIS was the prognostic factor for progression rate and disease-specific survival rate at 3 years (P = 0.008 and P = 0.035).

Conclusion

GC adjuvant chemotherapy is a safe conservative treatment for T1G3 bladder cancer, but effective is really a phase II study. Patients with T1G3 bladder cancer with concomitant CIS should be treated more aggressively because of the high risk of progression.  相似文献   
44.
目的:观察低血糖指数的膳食对2型糖尿病患者氧化应激状态的影响。方法:2004-10/11在上海市静安区二个社区卫生服务中心招募受试者,经医生明确诊断为2型糖尿病、病程超过6个月,体质量指数≥24kg/m2的老年糖尿病志愿者43名,受试者对试验知情同意。采用随机交叉试验随机分配至低血糖指数饮食组和高血糖指数饮食组,每种膳食分别连续使用4周,间隔洗脱期4周,比较试验前后患者超氧化物歧化酶、脂质过氧化产物丙二醛和谷胱甘肽过氧化物酶含量的变化。结果:受试者依从性好,除1人因试验期间发现肿瘤而退出试验,42名志愿者按设计要求完成试验。膳食干预后低血糖指数饮食组和高血糖指数饮食组的超氧化物歧化酶活力分别升高了15.68%和21.33%,丙二醛水平分别下降23.94%和21.55%,谷胱甘肽过氧化物酶活力分别升高了15.74%和17.09%;干预后低血糖指数饮食组丙二醛下降水平与高血糖指数饮食组比较差异有显著性意义(P<0.05),而超氧化物歧化酶和谷胱甘肽过氧化物酶活性两组间差异无显著性意义(P>0.05)。结论:在控制总能量的基础上给予平衡膳食能够改善其氧化应激水平,采用低血糖指数食物有助于氧化应激水平的改善。  相似文献   
45.
目的:观察吸烟者体内尼古丁代替主要产物可铁宁在佐剂性关节炎动物模型抗炎和调节免疫方面的作用。方法:实验于2005-10/2006-09在南方医科大学南方医院检验科及实验动物中心完成。实验动物:SD大鼠50只。实验分组和给药:随机选取SD大鼠40只注射完全弗氏佐剂,致炎建立佐剂性关节炎模型,剩余的10只SD大鼠为正常组。将40只佐剂性关节炎大鼠随机分为炎症组10只,可铁宁低、中、高剂量组各10只,可铁宁各组于佐剂注射后1周开始灌胃给药,分别给0.5,1.5,4.5g/kg体质量剂量药物,连续7d。实验评估:致炎后28d开始进行运用ELISA及流式细胞术,检测用药后对白细胞介素1β、白细胞介素2,T细胞增殖等指标(CD4 ,CD8 ,CD4 /CD8 )的影响。结果:50只大鼠全部进入结果分析。①各组大鼠血清中白细胞介素1β、白细胞介素2含量:与炎症组相比,可铁宁高、中、低剂量各组白细胞介素1β含量明显下降[(101.4±11.24),(53.40±8.23),(60.34±5.97),(72.31±8.06)ng/L,P<0.05],白细胞介素2含量明显升高[(121.3±21.2),(195.9±51.6),(174.3±40.3),(169.7±53.2)ng/L,P<0.05],且作用有一定的剂量依赖性。②各组大鼠淋巴细胞亚群CD4 ,CD8 ,CD4 /CD8 变化:造模第28天,与正常组相比,炎症组的CD4 增加,CD8 明显降低(P<0.05),CD4 与CD8 的比值显著增加(P<0.05);与炎症组相比较,可铁宁高剂量组的CD4 显著降低(P<0.05);可铁宁各组的CD8 明显增加(P<0.05),CD4 与CD8 比值显著下降,呈剂量依赖性。结论:可铁宁可调节大鼠血清中异常的白细胞介素1及白细胞介素2含量,可铁宁在试验动物水平有抗炎和免疫调节的作用。  相似文献   
46.
目的:综述干细胞治疗糖尿病的研究现状及未来发展。资料来源:应用计算机检索Pubmed2000-01/2006-11有关干细胞治疗糖尿病方面文献,检索词“diabetes mellitus and stem cell not review”,限定文章语言种类为English。资料选择:对检索到的干细胞治疗糖尿病相关文献进行整理,选取针对性强文章。同一领域文献则选择近期发表或权威杂志文章。资料提炼:共检索到359篇相关文献,有关胚胎干细胞、胰腺干细胞、造血干细胞、神经干细胞、骨髓基质干细胞在糖尿病方面研究文章50篇,其中29篇符合要求。资料综合:干细胞极强的自我更新能力和多向分化潜能为糖尿病的细胞治疗开辟了新途径,按其发育阶段不同可以将干细胞分为胚胎干细胞和胰腺干细胞、造血干细胞、神经干细胞、骨髓基质干细胞等成体干细胞。干细胞移植是治疗糖尿病的一条新途径。干细胞生成胰岛素分泌细胞前需要经过诱导分化、细胞选择和细胞成熟3个阶段。干细胞治疗糖尿病研究已取得一定进展,部分实验已纠正糖尿病动物的高血糖状态。结论:干细胞定向分化为胰岛β细胞研究为糖尿病患者点燃了新希望,其勿庸置疑的成为治疗糖尿病的最佳种子细胞。  相似文献   
47.
A 28-year-old man with no previous history of abdominal surgery presented at a local hospital with abdominal pain. He was diagnosed to have an intestinal obstruction and was treated conservatively. However, the symptoms persisted, and he was thereafter referred to this hospital. Plain abdominal radiographs demonstrated small-bowel gas. A computed tomographic scan of the abdomen disclosed wall thickening of an edematous, fluid-filled ileum. An exploratory laparotomy was performed to determine the cause of the intestinal obstruction. The ileum had herniated into the intersigmoid fossa, 100 cm proximal to the ileocecal valve, and the patient was diagnosed to have an intersigmoid hernia. Since the incarcerated portion of the small bowel was viable, reduction of the hernia and closure of the defect in the sigmoid mesocolon were performed. The postoperative course was uneventful. A sigmoid mesocolon hernia is an uncommon condition. This report presents a case of intersigmoid hernia and a review of 60 cases of sigmoid mesocolon hernia reported in Japan.  相似文献   
48.
Nuclear genes succinate dehydrogenase B subunit and succinate dehydrogenase D subunit, which encode two mitochondrial complex II subunits, are associated with the development of familial paraganglioma (PGL). Succinate dehydrogenase B subunit gene mutation is highly associated with extraadrenal PGL and subsequent distant metastasis. We describe the case of a 29-year-old Japanese man with a 3-year history of hypertension, headache, and palpitation. Endocrinological examinations showed that the patient had elevated levels of catecholamines, and imaging studies revealed a right paraaortic PGL without distant metastases. The PGL was surgically removed. Genetic analysis of the patient showed a heterozygous thymine deletion at position 470 (c.470delT) in exon 5 of the succinate dehydrogenase B subunit gene complementary DNA. This thymine deletion changed TTG (leucine) to TGA (stop codon) at codon 157 (L157X). It remains unclear whether this mutation was associated with PGL malignancy because the patient has had no metastases for the past 3 years. It has been recently reported that L157X is associated with malignant paraaortic PGL. Thus, strict follow-up is required because this succinate dehydrogenase B subunit gene's nonsense mutation (L157X) may be related to the malignancy.  相似文献   
49.

Background

There have been few epidemiological studies on gastroenteropancreatic neuroendocrine tumors (GEP-NETs) in Japan.

Methods

We examined the epidemiology of GEP-NETs [pancreatic endocrine tumors (PETs) and gastrointestinal neuroendocrine tumors (GI-NETs)] in Japan in 2005 using a nationwide stratified random sampling method.

Results

A total of 2,845 individuals received treatment for PETs. Prevalence was estimated as 2.23/100,000 with an annual onset incidence of 1.01/100,000. Non-functioning tumor (NF)-PET constituted 47.4%, followed by insulinoma (38.2%) and gastrinoma (7.9%). Distant metastases were reported in 21% patients with NF-PETs and occurred more frequently as tumor size increased (>2 cm). Multiple endocrine neoplasia type 1 (MEN-1) was detected in 10% of PETs but only in 6.1% of NF-PETs. NF-PETs were detected incidentally by physical examination in 24% patients. In 2005, an estimated 4,406 patients received treatment for GI-NETs. Prevalence was estimated as 3.45/100,000, with an annual onset incidence of 2.10/100,000. The locations of GI-NETs varied: foregut, 30.4%; midgut, 9.6%; and hindgut, 60.0%. Distant metastases were observed in 6%. Lymph node metastases occurred more frequently as tumor size increased (>1 cm). The frequency of MEN-1 complications was 1%. Physical examination revealed GI-NETs in 44% patients. The frequency of symptomatic GI-NETs was 3.4%. Interestingly, 77.1% of patients with foregut GI-NETs had type A gastritis.

Conclusion

Our results show there are large differences in GEP-NETs between Japan and Western nations, primarily due to differences in the presence of MEN-1 in NF-PETs and the location, symptomatic status, and prevalence of malignancy in GI-NETs.  相似文献   
50.
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