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51.
52.
M. RAUVALA K. AGLUND† U. PUISTOLA T. TURPEENNIEMI-HUJANEN‡ G. HORVATH§ R. WILLÉN & U. STENDAHL† 《International journal of gynecological cancer》2006,16(3):1297-1302
The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors. 相似文献
53.
Juin Fok-Seang Linda C. Smith-Thomas Sally Meiners Elizabeth Muir Jian-Sheng Du Elizabeth Housden Alan R. Johnson Andreas Faissner Herbert M. Geller Roger J. Keynes John H. Rogers James W. Fawcett 《Brain research》1995,689(2):207
The adult mammalian central nervous system (CNS) lacks the capacity to support axonal regeneration. There is increasing evidence to suggest that astrocytes, the major glial population in the CNS, may possess both axon-growth promoting and axon-growth inhibitory properties and the latter may contribute to the poor regenerative capacity of the CNS. In order to examine the molecular differences between axon-growth permissive and axon-growth inhibitory astrocytes, a panel of astrocyte cell lines exhibiting a range of axon-growth promoting properties was generated and analysed. No clear correlation was found between the axon-growth promoting properties of these astrocyte cell lines with: (i) the expression of known neurite-outgrowth promoting molecules such as laminin, fibronectin andN-cadherin; (ii) the expression of known inhibitory molecules such tenascin and chondroitin sulphate proteoglycan; (iii) plasminogen activator and plasminogen activator inhibitor activity; and (iv) growth cone collapsing activity. EM studies on aggregates formed from astrocyte cell lines, however, revealed the presence of an abundance of extracellular matrix material associated with the more inhibitory astrocyte cell lines. When matrix deposited by astrocyte cell lines was assessed for axon-growth promoting activity, matrix from permissive lines was found to be a good substrate, whereas matrix from the inhibitory astrocyte lines was a poor substrate for neuritic growth. Our findings, taken together, suggest that the functional differences between the permissive and the inhibitory astrocyte cell lines reside largely with the ECM. 相似文献
54.
报道新化合物A-失碳-17β-羟基-17α-乙炔基-Δ3(5),9(10)-雌甾二烯-2-酮2的合成。文中探讨了用炔钾粗品对A-失碳-Δ3(5),9(10)-雌甾二烯-2,17-二酮1和A-失碳-6β,19-环氧-Δ3-雄甾-2,17-二酮3的选择性炔化,分别得标题化合物2(44%)及A-失碳-17β-羟基-17α-乙炔基-6β,19-环氧-Δ3雄甾-2-酮4(65%),4经还原性破开环氧、去羟甲基和去醋酰氧基合成了标题化合物2。四步总收率为34%。 相似文献
55.
Acute Immobilization Stress and Intraventricular Injection of CRF Suppress Naloxone-Induced LH Release in Ovariectomized Estrogen-Primed Rats 总被引:1,自引:0,他引:1
Tatsuo Akema Atsuhiko Chiba Reiji Shinozaki Morihiro Oshida Fukuko Kimura & Jun-ichi Toyoda 《Journal of neuroendocrinology》1996,8(8):647-652
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20 mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10 min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30 min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5 min after the stress onset, and was still evident 60 min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3 h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5 μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50 μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s). 相似文献
56.
Regulations evolve and risks management becomes one of the biomedical engineers' preoccupations. Thus, risks are various, and consequently it is difficult to identify, to manage and to bring them under control. Furthermore, regulations exist for sectors like healthcare technology monitoring, but it is not the same thing for instance for the risks linked to the maintenance. Thus regulation in the sector of maintenance evolves and the decree of the 1st July law of health safety is going to modify the biomedical environment. The goal of this work is to study the tools and the methods of risks management that have been used for several years in the industrial field and to use them for some biomedical equipment like monitors or IV pumps. These methods adapted to these equipment will allow us to determine some appropriate rules of maintenance. 相似文献
57.
目的:为设计维甲酸治疗神经母细胞瘤可能的有效方案,本文对9-顺式维甲酸(9-cis retinoic acid,9-cisRA)体外诱导分化神经母细胞瘤细胞(SK-N-SH)作用进行了研究。方法:SK-N-SH细胞经9-cisRA处理后,采用相差显微镜,神经纤维银染法,透射电镜观察等手段。观察9-cisRA对细胞生长的影响。结果:9-cisRA作用SK-N-SH细胞7d后,细胞形态发生变化;12d时出现神经原性表型,多个细胞形成“神经节”,节间形成粗而长的类神经纤维;尼氏小体和银染法亦证明细胞产生显著分化,透射电镜观察结果表明,9-cisRA对该细胞有分化作用。却无明显凋亡诱导作用。结论:9-cisRA对神经母细胞瘤细胞体外能产生明显诱导分化作用。 相似文献
58.
背景:与小肠黏膜下层等材料相比,脱细胞血管具有天然管状结构,与输尿管形态结构相近,替代输尿管时仅需端端吻合即可,手术操作简单,血管外壁光滑,获取及制备方法简便等优点。
目的:拟应用同种颈动脉血管无细胞基质体外构建输尿管。
设计、时间及地点:观察性实验,于2006-09/2008-06在上海交通大学医学院附属新华医院动物实验中心完成。
材料:长风杂交白猪由上海松联实验动物公司提供。上海交通大学医学院实验动物中心提供的健康成年大鼠8只,用于血管无细胞基质的动物毒性实验。
方法:剥去猪颈动脉血管外膜,PBS冲洗若干遍,然后将血管置于pH 7.1 的PBS中4 ℃下振荡清洗,0.5%十二烷基硫酸钠振荡24 h,后使用双蒸水4 ℃下反复振荡洗涤1周,每日换双蒸水2次。对于解剖过程中肌肉残留相对稍多的血管,在双蒸水洗涤前以混合消化液37 ℃下振荡消化约2 h,再行双蒸水洗涤。制备的无细胞基质置于青、链霉素溶液中,4 ℃保存,完成脱细胞支架制备。
主要观察指标:光镜及电镜观察脱细胞后管壁无细胞基质片的主要成分。将同种异体来源内皮祖细胞培养增殖后植入血管无细胞基质,观察细胞生长情况,并进行血管无细胞基质动物毒性实验。拉力实验了解血管无细胞基质材料的收缩性能。
结果:颈动脉血管无细胞基质中已无细胞成分,无细胞基质主要由胶原成分组成。扫描电镜未见该材料表面存在细胞及细胞碎片,同时发现该无细胞基质存在孔隙样结构。体外同种异体来源的内皮祖细胞培养增殖后植入血管无细胞基质,细胞黏附于无细胞基质。血管无细胞基质按毒性分级属于无毒级。拉力实验说明该无细胞基质具有一定的韧性和牵张性。
结论:采用胰酶和十二烷基硫酸钠制备的颈动脉血管无细胞基质材料无细胞残留,具有一定的韧性和牵张性,种植于其中的种子细胞具备一定的生长能力。 相似文献
59.
Charles Opondo Stephen Ntoburi John Wagai Jackline Wafula Aggrey Wasunna Fred Were Annah Wamae Santau Migiro Grace Irimu Mike English 《Tropical medicine & international health : TM & IH》2009,14(10):1165-1172
Objective To assess the availability of resources that support the provision of basic neonatal care in eight first‐referral level (district) hospitals in Kenya. Methods We selected two hospitals each from four of Kenya’s eight provinces with the aim of representing the diversity of this part of the health system in Kenya. We created a checklist of 53 indicator items necessary for providing essential basic care to newborns and assessed their availability at each of the eight hospitals by direct observation, and then compared our observations with the opinions of health workers providing care to newborns on recent availability for some items, using a self‐administered structured questionnaire. Results The hospitals surveyed were often unable to maintain a safe hygienic environment for patients and health care workers; staffing was insufficient and sometimes poorly organised to support the provision of care; some key equipment, laboratory tests, drugs and consumables were not available while patient management guidelines were missing in all sites. Conclusion Hospitals appear relatively poorly prepared to fill their proposed role in ensuring newborn survival. More effective interventions are needed to improve them to meet the special needs of this at‐risk group. 相似文献
60.
K. Toutouzas E. Tsiamis M. Drakopoulou A. Synetos J. Karampelas M. Riga C. Tsioufis D. Tousoulis E. Stefanadi C. Vlassis C. Stefanadis 《Diabetes & metabolism》2009,35(4):299-304
AimsLocal coronary and systemic inflammation is pronounced in patients with diabetes mellitus (DM). Intracoronary thermography detects local inflammation and C-reactive protein (CRP) is a marker of systemic inflammation. We investigated whether or not, in patients with DM, thermal heterogeneity of culprit lesions (CLs) correlates with that of non-culprit lesions (NCLs) and with systemic inflammation.MethodsWe included DM patients who had two angiographically significant lesions and were undergoing percutaneous coronary intervention. We measured the temperature difference (ΔT) between the lesion and proximal vessel wall.ResultsWe included 104 (n = 208 lesions) patients: 32 (n = 64 lesions) had DM and 72 (n = 144 lesions) were non-DM (control group). ΔT was increased in DM in both CLs and NCLs (CLs: DM = 0.12 ± 0.06 °C; no DM = 0.06 ± 0.04 °C; P < 0.01 versus NCLs: DM = 0.13 ± 0.08 °C versus no DM = 0.06 ± 0.05 °C; P < 0.01). Patients with DM had similar ΔT in CLs and NCLs (P = 0.49). A linear correlation was detected between heat production in all lesions and CRP (R = 0.45; P < 0.01), which was attributed to the correlation of ΔT in lesions of patients with DM and CRP (R = 0.32; P < 0.01). In lesions of patients with low CRP, a greater rate of discrepancy was found, as 100% of lesions in patients with DM versus 66.1% of lesions of patients without DM had a high ΔT in one or both lesions (P < 0.01).ConclusionIn patients with DM, local inflammatory activation is diffuse and correlates with systemic inflammation. However, low systemic inflammatory activation does not always predict an increase in local thermal heterogeneity. 相似文献