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101.
Intraventricular hemorrhage (IVH) in preterm infants is well known to be associated with the high morbidity and mortality of this group. Previous studies have suggested altered cerebral blood flow (CBF) as an important pathologic factor. We measured the CBF in nearterm rabbit fetuses using the hydrogen clearance technique. The local CBF of the rabbit fetuses was significantly low compared with that of the maternal rabbits. The response of CBF to changes in PaCO2 was observed in rabbit fetuses. The CO2 reactivity index of the fetal rabbit was lower than that of the maternal rabbit. This low CO2 reactivity might reflect the immaturity of the fetal brain and its low CBF. We were unable to monitor the fetal blood pressure, but the fetal CBF remained stable when the maternal blood pressure was altered. It is well known that IVH in preterm infants originates from the subependymal germinal matrix and that this has many fragile vessels. Our observation suggests that even a small increase of CBF during hypercapnia might have a large effect towards producing hemorrhage.  相似文献   
102.
'Gliosarcomas' have long been considered to be mixed gliomas and sarcomas. The present study failed to define criteria which clearly delineate 'gliosarcomas' from glioblastoma multiforme and suggests that 'gliosarcomas' should be considered as spindle cell glioblastomas. A total of six cases originally diagnosed as 'gliosarcomas' were compared with four cases of glioblastoma multiforme. No clinical or prognostic features were defined which would clearly separate 'gliosarcomas' from glioblastoma multiforme. Macroscopically, biopsies from 'gliosarcomas' ranged from firm, apparently well-circumscribed tumours to poorly circumscribed lesions with a soft consistency resembling glioblastoma multiforme. Histology revealed a continuous spectrum in which 'gliosarcomas' with large reticulin-rich areas of spindle cells merged with typical glioblastomas containing only small islands of spindle cells and reticulin staining. Immunocytochemistry for glial fibrillary acidic protein (GFAP); S100 protein and alpha-smooth muscle actin (ASMA) showed that the majority of cells in reticulin-poor areas of 'gliosarcoma' and glioblastomas expressed S100 protein and GFAP; many expressed ASMA and some expressed both GFAP and ASMA. Spindle cells in reticulin-rich areas of 'gliosarcomas' and glioblastomas most frequently expressed ASMA but many cells also expressed S100 protein and GFAP; some cells expressed both GFAP and ASMA. The results of this study and a review of the literature suggests that there is a clinical, radiological and pathological continuum with glioblastoma and 'gliosarcoma' at different ends of the spectrum. It is suggested, therefore, that most, if not all, 'gliosarcomas' be redesignated as spindle cell glioblastomas and not be considered as a mixture of glioma and sarcoma.  相似文献   
103.
ABSTRACT: The culture supernatant of the TTK-1 cell line, established from human decidual tissue, was found to contain a factor that strongly suppressed the mixed lymphocyte reaction (MLR). The mechanism of the MLR-suppressive activity as well as the biochemical characterization of this factor was analyzed. The TTK-1 supernatant suppressed the MLR much more strongly than the culture supernatants of the three other malignant cell lines examined. The molecular weight of this factor was estimated to be between 43 kilodaltons (kd) and 67 kd by gel filtration chromatography. The TTK-1 supernatant also suppressed the proliferation of the interleukin 2 (IL-2)-dependent T cell lines, but did not suppress that of the IL-2-independent T cell lines, suggesting that the TTK-1 supernatant inhibited the action of IL-2 and subsequently suppressed the MLR. The fact that the TTK-1 cell line originated from human decidual tissue might imply the important role of this factor in immunological fetomaternal balance.  相似文献   
104.
强直性脊柱炎患者外周血CD62P的表达   总被引:1,自引:1,他引:0  
目的探讨剖宫产指征的变化情况,分析影响剖宫产率的因素。方法 回顾性分析1393例剖宫产患者的临床资料。结果2年的平均剖宫产率为66.7%,其中2004年的剖宫产率为59.9%,2005年的剖富产率为72.2%,差异有统计学意义(P〈0.05)。剖宫产率的主要影响因素依次为社会因素(29.43%)、胎儿宫内窘迫(25.13%)、胎位异常(9.62%)、巨大胎儿(7.25%)、中至重度妊娠高血压综合征(6.25%)。结论剖宫产率的上升不只是一个纯医学问题,社会因素使剖宫产指征相对扩大,只有合理掌握剖宫产指征,通过医患双方、社会的共同努力,才能更好地降低剖宫产率。  相似文献   
105.
目的探索以虚拟现实技术为基础的枢椎椎弓根螺钉置人方法。方法选取8具成人颅一颈椎标本,采用改良四柱式定位框架固定于枕颈,使颅-颈-肩形成统一刚体,保持空间位置恒定,CT薄层扫描获取枢椎三维定位信息,采用Aero—Tech立体定向手术规划系统三维建模,设计安全、可视化、个体化的虚拟置钉路径,反复虚拟演示验证钉道安全后,导向弓把持下置人导向钢针,复查CT评价置钉的准确性。结果16个枢椎椎弓根置钉过程中,方向出现偏差(横突孔突破)1个,失败率为6.25%。结论目标椎弓根的容积三维重建、置钉路径可视化设计和虚拟演示,使操作过程简单、直观而精确,不需要线形和角性参数的测量;加上导向抓持装置提供的稳定性,使该技术具有很好的临床应用前景。  相似文献   
106.
Immunocytochemical methods have been used to examine the localisation of 3 neurofilament proteins and the calcium binding protein, calbindin D28k, in whole mount preparations of the submucous plexus in the Wistar rat. Neurofilament-M (160 kDA protein) was present in 40% of the submucosal neurons, staining fine filaments in the soma and the axonal processes. Calbindin D28k was present in 40% of the submucosal neurons staining both the soma and nerves within the plexus. The neurofilament proteins and calbindin D28k were never observed within the same neurons. Neurofilament-M was co-localised with substance P and calcitonin gene-related peptide but not somatostatin or the other neuropeptides investigated. Calbindib D28k was co-localised with vasoactive intestinal polypeptide and neuropeptide Y. Galanin- and somatostatin-immunoreactive neurons did not contain either the neurofilament proteins or calbindin D28k. The results demonstrate the presence of subsets of submucosal neurons that can be distinguished by the presence of neurofilament-M or calbinsin D28k.  相似文献   
107.
This article considers the unique challenges and opportunities that health care providers (HCPs) face when they address the sexual and reproductive health and rights of young women accessing services. Some of the difficulties that HCPs encounter in their work are highlighted, including poor remuneration, the impact of their personal biases and the effect of an under-equipped working environment. The financial, logistical and emotional challenges young people face in accessing services are also described, as well as some small changes that could promote fruitful partnerships between HCPs and their young clientele. Also considered is how international documents concerning reproductive health can be utilized as advocacy tools to ensure that, when governments speak of making young people's needs a priority, resources are also made a priority-so that reproductive health can become a reality for all young people.  相似文献   
108.
目的 探讨端粒酶逆转录酶(hTERT)和环氧化酶(cox)-2在乳腺浸润性导管癌中的表达及其临床意义.方法 使用免疫组织化学法分别检测45例乳腺浸润性导管癌和22例乳腺良性病变标本的hTERT和COX-2蛋白表达情况.结果 hTERT在乳腺浸润性导管癌中阳性表达率fig71.11%,明显高于乳腺良性病变9.09%,两者比较差异有统计学意义(P<0.05).hTERT阳性表达与乳腺浸润性导管癌患者的年龄、肿瘤大小、腋窝淋巴结转移情况及雌、孕激素表达水平无相关性(P>0.05),与Her-2表达存在显著相关性(P<0.05).COX-2在乳腺浸润性导管癌中的阳性表达率为82.22%,明显高于乳腺良性病变50.00%,两者比较差异有统计学意义(P<0.05).COX-2阳性表达与乳腺浸润性导管癌患者腋窝淋巴结转移情况、Her-2、ER阳性表达有关(P<0.05).在乳腺浸润性导管癌中hTERT阳性表达与COX-2阳性表达呈正相关(r=0.557,P<0.01).结论 hTERT与COX-2在乳腺浸润性导管癌中的表达显著高于在乳腺良性病变中的表达,hTERT与COX-2在乳腺癌的发生、发展中起重要作用.hTERT表达与COX-2表达存在显著相关性,COX-2的过度表达可能是端粒酶激活和调节的机制之一.  相似文献   
109.
110.
Abstract   We evaluated the associations between glycemic therapies and prevalence of diabetic peripheral neuropathy (DPN) at baseline among participants in the Bypass Angioplasty Revascularization Investigation 2 Diabetes (BARI 2D) trial on medical and revascularization therapies for coronary artery disease (CAD) and on insulin-sensitizing vs. insulin-providing treatments for diabetes. A total of 2,368 patients with type 2 diabetes and CAD was evaluated. DPN was defined as clinical examination score >2 using the Michigan Neuropathy Screening Instrument (MNSI). DPN odds ratios across different groups of glycemic therapy were evaluated by multiple logistic regression adjusted for multiple covariates including age, sex, hemoglobin A1c (HbA1c), and diabetes duration. Fifty-one percent of BARI 2D subjects with valid baseline characteristics and MNSI scores had DPN. After adjusting for all variables, use of insulin was significantly associated with DPN (OR = 1.57, 95% CI: 1.15–2.13). Patients on sulfonylurea (SU) or combination of SU/metformin (Met)/thiazolidinediones (TZD) had marginally higher rates of DPN than the Met/TZD group. This cross-sectional study in a cohort of patients with type 2 diabetes and CAD showed association of insulin use with higher DPN prevalence, independent of disease duration, glycemic control, and other characteristics. The causality between a glycemic control strategy and DPN cannot be evaluated in this cross-sectional study, but continued assessment of DPN and randomized therapies in BARI 2D trial may provide further explanations on the development of DPN.  相似文献   
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