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31.
Meng-Liang Zhou Ji-Xin Shi Chun-Hua Hang Hui-Lin Cheng Xiao-Ping Qi Lei Mao Ke-Fei Chen Hong-Xia Yin 《Journal of cerebral blood flow and metabolism》2007,27(9):1583-1592
Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response. 相似文献
32.
Polytetrafluoroethylene (PTFE) microvascular prostheses with a fibril length of 30 microns were pretreated with alcohol (n = 18), implanted into the abdominal aorta of rats and were evaluated at 1 day (n = 3), 1 week (n = 3), 3 weeks (n = 6) and 6 weeks (n = 6) to determine whether alcohol-pretreatment might improve their healing. Untreated PTFE microvascular prostheses (n = 18) functioned as controls (all prostheses: length 10 mm, I.D. 1.5 mm). The alcohol-pretreated PTFE microarterial prostheses were initially completely filled and covered with clot and showed fast and complete healing within 6 weeks: endothelial cells and smooth muscle cells on the luminal surface, and the interstices filled with fibrous-like tissue. In contrast, the untreated PTFE prostheses were initially not filled or covered with clot and showed only healing near the anastomotic sites and scarce tissue ingrowth into the wall. These results demonstrate that alcohol-pretreatment improves the healing characteristics of PTFE microarterial prostheses with a fibril length of 30 microns. The alcohol-pretreatment renders the PTFE material more accessible to clot and subsequently to cells. 相似文献
33.
QuantitativerelationshipbetweenpupillaryreflexfeatureanditsdiopterinretinoscopyXuShang(徐上);JiShangnian(计尚年)(DepartmentofOphth... 相似文献
34.
Reversal of fulminant hepatic failure using an extracorporeal liver assist device. 总被引:20,自引:0,他引:20
N L Sussman M G Chong T Koussayer D E He T A Shang H H Whisennand J H Kelly 《Hepatology (Baltimore, Md.)》1992,16(1):60-65
Liver transplantation is currently the only effective therapy for patients with fulminant hepatic failure. The availability of an artificial liver could bridge these patients through the relatively brief crisis period and allow their own livers to regenerate, providing a more favorable outcome and sparing the trauma and expense of transplant. We have developed a device consisting of a highly differentiated human liver cell line cultured in a hollow fiber cartridge. This device is capable of supporting dogs with acetaminophen-induced fulminant hepatic failure for a period long enough for their own livers to resume function. Even though liver function tests such as albumin and prothrombin time became extremely abnormal during the course of the experiment, the dogs did not become encephalopathic. Two of the three treated animals recovered sufficient liver function after 42 to 48 hr of treatment that they could be disconnected from the device, and they survived the experiment. Histological results and serum ALT levels suggest that the device affected the course of the disease in two animals, allowing recovery of hepatocytes that would otherwise have lysed. In the third animal, regenerative nodules demonstrated that, even in the presence of severe liver injury, the device was capable of supporting total liver function. 相似文献
35.
目的研究妊高征孕妇心率变异性(HRV)、血压变异性(BPV)和压力反射敏感性(BRS)的改变.方法用无创伤测定和频谱分析方法,检测31名正常妊娠孕妇和19名中、重度妊高征孕妇的HRV、BPV和自发性BRS,数据用SPSS 10.0软件分析.结果妊高征组和正常妊娠组相比,HRV各指标有下降趋势,但无统计学意义(P>0.05).妊高征孕妇BPV的低频成分显著高于正常妊娠孕妇(P<0.05),BRS较正常妊娠孕妇降低(P<0.05).结论妊高征孕妇交感神经对血压调节的活动性较正常妊娠孕妇增强;压力反射功能受损可能是妊高征发病过程中一重要环节. 相似文献
36.
37.
Oscar E. Mendez MD Jingzi Shang MD PhD Charles A. Jungreis MD Daniel I. Kaufer MD 《Journal of neuroimaging》2003,13(2):147-151
Two middle-aged patients presented with rapidly progressive dementia and ataxia, nonspecific electroencephalography findings, and negative cerebrospinal fluid (CSF) protein 14-3-3. Both patients underwent brain magnetic resonance imaging (MRI) scans that demonstrated abnormalities on diffusion-weighted imaging (DWI) sequences, and both were later confirmed to have Creutzfeldt-Jakob disease. (CJD) by tissue examination. Because a recent position paper from the American Academy of Neurology characterized CSF protein 14-3-3 as a gold standard for clinically diagnosing CJD, the authors reviewed studies of CJD in which DWI-MRI imaging and CSF protein 14-3-3 studies were both performed. Among 19 reported cases of CJD with DWI-MRI lesions, CSF protein 14-3-3 was negative in 6 cases and positive in 2 others. The authors' findings suggest that multifocal cortical and subcortical hyperintensities confined to gray matter regions in DWI-MRI may be a more useful noninvasive diagnostic marker for CJD than CSF protein 14-3-3. These observations provide a compelling rationale for a prospective comparative study. 相似文献
38.
雷俊 《中华实用中西医杂志》2006,19(8):873-873
慢性泪囊炎为眼科常见病之一,需行手术治疗。我科近2年来对86例慢性泪囊炎患者经鼻腔逆行插管术进行了整体护理,取得了良好的效果。现报告如下: 相似文献
39.
目的探讨大学生的自我和谐与交往焦虑的特点和关系。方法采用自我和谐量表和交往焦虑量表对310名大学生进行调查。结果男生在自我灵活性和自我和谐上得分低于女生(P〈0.01),研究生在自我灵活性上得分低于本科生(P〈0.01),理科生在社交焦虑上得分低于文科生(P〈0.05);高自我和谐组在社交焦虑上得分低于低自我和谐组(P〈0.05);从总体上看,社交焦虑与自我与经验的不和谐、自我刻板性、总体的自我和谐均呈正相关(P〈0.01)。结论大学生的自我和谐和社交焦虑之间均存在相关,自我和谐对社交焦虑具有良好的预测作用。 相似文献
40.
Shang Wen Chen Ji An Liang Shih Neng Yang Hui Ling Ko Fang Jen Lin 《Radiotherapy and oncology》2003,67(1):69-76
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups. 相似文献