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排序方式: 共有871条查询结果,搜索用时 15 毫秒
41.
目的:检测MCM5蛋白和PCNA在肺癌组织中的表达,探讨两者与肺癌各临床病理因素之间的关系及两者相互的联系,从而为评估肺癌的发生发展、预后及治疗提供理论依据。方法:运用免疫组织化学技术分别检测MCM5蛋白和PCNA在68例肺癌组织和20例正常组织中的表达情况,分析其与临床病理因素之间的关系及两者相互的联系。结果:MCM5表达的阳性信号位于细胞核,胞浆无着色。在正常肺组织中,MCM5的表达局限在上皮基底部的1/3至1/2的细胞,在肺癌组织中,MCM5的表达分布广泛,靠近上皮表面的细胞也可见大量表达。(1)正常肺组织和肺癌组织的MCM5的表达的差别有统计学意义(P<0.01)。(2)肺癌中MCM5表达与分化程度、淋巴结转移有显著相关性(P<0.05),与病人年龄、性别无显著相关性(P>0.05)。(3)PCNA的表达与肺癌的分化程度无显著相关性(P>0.05)。(4)在肺正常组织中,PCNA标记指数高于MCM5标记指数,两者具有显著差异性(P<0.05)。在肺癌组织中,PCNA与MCM5标记指数无显著差异性(P>0.05)。结论:(1)在肺组织中,微小染色体维持蛋白5(MCM5)是一种可靠的细胞增殖标志物。根据MCM5染色的组织结构差异和平均光密度能比较准确区分肺正常组织和癌组织。MCM5表达与肺癌的分化程度显著相关,因此MCM5表达可以提示肺癌的恶性程度,有助于临床判断病人的预后以及选择合适的治疗方法。MCM5与其他增殖标志PCNA相比是一种更好的细胞增殖标志物,是肺癌细胞的更好标志和分级指标。(2)PCNA在肺癌组织中过表达,提示PCNA的过表达与肺癌的发生发展关系密切。 相似文献
42.
MSTM Almeida SCB Lima LL Carvalho JVM Almeida LG Santos JRA Rolim TE Rocha 《Journal of cutaneous pathology》2010,37(11):1170-1173
Systemic sclerosis (SSc) is an autoimmune systemic disease characterized by small vessel involvement that leads to tissue ischemia and fibroblast stimulation resulting in accumulation of collagen (fibrosis) in the skin and internal organs. Lipomembranous panniculitis is a peculiar type of fat necrosis and has been reported with clinical conditions, commonly with peripheral vascular diseases. We describe a case of a 43‐year‐old woman with SSc manifestations, who presented with black scaly skin plaques, associated with thickening of the subcutaneous fat tissue, on the lateral surface of her thighs, her calves, gluteal area and lower abdomen. Biopsy revealed lipomembranous panniculitis. Lipomembranous changes have been seen in connective tissue disorders such as lupus profundus, morphea, systemic sclerosis and panniculitis associated with dermatomyositis, but rarely in thighs, calves, gluteal area and lower abdomen. Almeida MSTM, Lima SCB, Carvalho LL, Almeida JVM, Santos LG, Rolim JRA, Rocha TE. Panniculitis–An unusual cutaneous manifestation of systemic sclerosis. 相似文献
43.
44.
加替沙星无菌检查方法的建立与标准操作探讨 总被引:4,自引:0,他引:4
目的:建立加替沙星原料及制剂无菌检查法及标准操作方法。方法:按2005年版中国药典无菌检查法验证实验的有关要求,通过接种阳性代表菌株,对薄膜过滤、添加中和剂等去除加替沙星抗菌活性的实验方法和条件进行验证,逐步建立加替沙星原料及制剂无菌检查的标准操作方法。结果:在对加替沙星不同原料及制剂样品适当的处理基础上,采用薄膜过滤法,以0.1%蛋白胨水溶液作为冲洗液,约每滤筒300 mL 的冲洗量,每筒培养基中加入0.1 mol·L~(-1)硫酸锰溶液3 mL 可去除加替沙星对细菌的抑菌作用。结论:加替沙星具有较强的抑菌活性,通过适当的样品处理、薄膜过滤法和添加硫酸锰溶液作为重金属络合剂,去除加替沙星抑菌活性,可对解决喹诺酮类抗生素无菌检查问题起到较好的参考作用。 相似文献
45.
保健食品微生物限度检查的方法学验证 总被引:3,自引:0,他引:3
目的:确认对保健食品进行微生物限度检查时,昕采用的细菌、霉菌及酵母菌计数和控制菌检查方法是否适合于该保健食品的微生物限度检查。方法:按2005年版中国药典微生物限度检查法及方法学验证实验要求,对21种保健食品进行了方法学验证。结果:10个品种(血尔口服液、金舒通胶囊、事轻松胶囊、梦玉胶囊等)分别对金黄色葡萄球菌和枯草芽孢杆菌有明显的抑菌作用,阳性对照菌回收率均低于70%。结论:保健食品采用 GB/T4789-2003食品卫生微生物学检查法进行检查时,其检验结果可能不够科学,建议参照2005年版中国药典要求,通过方法验证实验建立合理的检验方法。 相似文献
46.
BA DARLOW TE INDER KB SLUIS G NUTHALL N MOGRIDGE CC WINTERBOURN 《Journal of paediatrics and child health》1995,31(4):339-344
Objective: New Zealand soils are deficient in the essential micronutrient, selenium. New Zealand infants have low selenium levels at birth and experience a further decline if fed cows milk based formula. This study examined the selenium status of infants fed with a new commercially available selenium supplemented formula.
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
Methodology Forty-four newborn infants, whose mothers wished to formula feed, were randomized in an open controlled trial to be fed a commercially available selenium supplemented cows milk formula (containing 17 μg Se/L) or an unsupplemented formula (containing 4.6 μg Se/L). Cord, 1 and 3 month blood samples were obtained for selenium status (plasma and red cell selenium and glutathione peroxidase) and thyroid function.
Results Mean plasma selenium and glutathione peroxidase values were significantly higher in supplemented than unsupplemented infants at 1 month (unpaired t -tests; P <0.0001 and P = 0.001 respectively) and 3 months ( P <0.0001 and P = 0.0005). Analysis within treatment groups between time points (paired t -tests) showed that selenium supplementation prevented the fall in plasma selenium from birth to 1 month seen in unsupplemented infants and was associated with a rise in levels between 1 and 3 months ( P = 0.002).
Conclusions Supplementing cows milk formula with selenium to replicate the levels found in breast milk is nutritionally sound. Feeding from a few days of age with a formula containing 17 μg Se/L in infants with low selenium status at birth is sufficient to cause a rise to 80% of adult levels at 3 months of age. 相似文献
47.
Accounts by journalists of wars in several countries of sub-Saharan Africa in the 1990s have raised concern that ethnic cleavages and overlapping religious and racial affiliations may widen the inequalities in health and survival among ethnic groups throughout the region, particularly among children. Paradoxically, there has been no systematic examination of ethnic inequality in child survival chances across countries in the region. This paper uses survey data collected in the 1990s in 11 countries (Central African Republic, Côte d''Ivoire, Ghana, Kenya, Mali, Namibia, Niger, Rwanda, Senegal, Uganda, and Zambia) to examine whether ethnic inequality in child mortality has been present and spreading in sub-Saharan Africa since the 1980s. The focus was on one or two groups in each country which may have experienced distinct child health and survival chances, compared to the rest of the national population, as a result of their geographical location. The factors examined to explain potential child survival inequalities among ethnic groups included residence in the largest city, household economic conditions, educational attainment and nutritional status of the mothers, use of modern maternal and child health services including immunization, and patterns of fertility and migration. The results show remarkable consistency. In all 11 countries there were significant differentials between ethnic groups in the odds of dying during infancy or before the age of 5 years. Multivariate analysis shows that ethnic child mortality differences are closely linked with economic inequality in many countries, and perhaps with differential use of child health services in countries of the Sahel region. Strong and consistent results in this study support placing the notion of ethnicity at the forefront of theories and analyses of child mortality in Africa which incorporate social, and not purely epidemiological, considerations. Moreover, the typical advantage of relatively small, clearly defined ethnic groups, as compared to the majority in the national population, according to fundamental indicators of wellbeing--child survival, education, housing, and so forth--suggests that many countries in sub-Saharan Africa, despite their widespread poverty, are as marked by social inequality as are countries in other regions in the world. 相似文献
48.
49.
Hematogenous spread as a mechanism for the generation of
abdominal wound metastases following laparoscopy 总被引:2,自引:0,他引:2
Background: We designed this study to determine whether hematogenous spread has a role in the etiology of port site metastases
following laparoscopic surgery. Methods: The study design had two parts. In experiment 1, two groups (n = 30) of male Dark
Agouti rats were studied. Under general anesthesia, the first group (20 rats) underwent 15 mins of laparoscopic insufflation,
followed by an injection of a suspension of 105 Dark Agouti mammary adenocarcinoma (DAMA) cells into the internal jugular
vein and a further 15-mins period of insufflation. The laparoscopic ports were then removed, and the wounds were closed and
marked. In the second group (n = 10), the procedure was identical except that a 2.5-cm midline laparotomy was performed 15
mins after the commencement of anesthesia and insufflation was not used. The laparotomy was closed in two layers. In experiment
2, one group (n = 4) was studied. The study protocol was identical to the first laparoscopic group except that a larger number
of 106 DAMA cells were injected. All rats in both experiments were killed 15 days later, and the injection site, laparoscopy
wounds, and laparotomy wound were examined histologically by a blinded histopathologist. Results: In experiment 1, one port
site tumor was detected in the laparoscopic group and no wound metastases were found in the laparotomy group. Postoperative
weight loss was significantly less in the laparoscopic group (p < 0.001). In experiment 2, no port site metastases were detected.
Conclusion: Although hematogenous spread is a possible mechanism in the development of port site metastases, judging from
the low number of port site metastases in this study as compared to previous reports using this tumor model, this mechanism
is unlikely to be a major contributor to the problem of wound metastasis following laparoscopy. 相似文献
50.
Experimental study of peritoneal blood flow and insufflation pressure during laparoscopy 总被引:13,自引:0,他引:13
Brundell SM Tsopelas C Chatterton B Touloumtzoglou J Hewett PJ 《The British journal of surgery》2002,89(5):617-622
BACKGROUND: Port-site metastases after laparoscopic surgery may occur with greater frequency than would be expected following open resection of intra-abdominal malignancies, but the causal mechanism for this is incompletely understood. The possibility that insufflation may increase peritoneal blood flow producing a wound environment conducive to the formation of metastases was investigated.METHODS: The effects of insufflation gas type and pressure were studied in 30-kg female pigs. Pigs were divided into five groups, which were subjected to insufflation at 12 mmHg pressure with helium, insufflation at 12, 8 or 4 mmHg pressure with carbon dioxide, or laparotomy. A microsphere technique utilizing two distinct radiotracers, 99mTc-labelled macroaggregated albumin (MAA) and 51Cr-labelled MAA, was used to study blood flow to the peritoneum, liver and kidneys.RESULTS: Insufflation with carbon dioxide or helium gases had no effect on renal (P < 0.09) or hepatic blood flow (P = 0.54). However, insufflation significantly increased peritoneal blood flow when carbon dioxide (P < 0.05), but not when helium (P = 0.99), was used as the insufflating gas.CONCLUSION: These data suggest that blood flow within the peritoneum is influenced by insufflation with carbon dioxide. It is conceivable that such hyperaemia could increase the propensity for implanted tumour cells to metastasize in these sites following laparoscopy. 相似文献