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91.
A J Roon W S Moore J Goldstone H Towan G Campagna 《The Journal of surgical research》1977,22(3):165-173
In order to study the comparative thrombogenicity of neointimal surfaces that develop with three types of vascular graft materials (ultralightweight knitted dacron, knitted dacron external velour, and expanded Teflon), 36 female mongrel dogs had their infrarenal aortas alternately replaced with one of the three grafts. At the end of 3 or 6 months, the grafts were removed and the surface thrombogenicity of the neointimal surface was determined. Each graft was examined visually and microscopically for evidence of “healing.” At 6 months the external velour graft is lined more frequently than the other two grafts. The external velour graft has a markedly better incidence of cellular healing noted microscopically than the other two grafts at both time intervals. While the expanded Teflon has an initially lower surface thrombogenicity (probably due to the characteristics of Teflon surface), at 6 months, the velour graft has the lowest surface thrombogenicity. This is most likely due to cellular healing. Of all the completely lined grafts at both time intervals, the surface thrombogenicity of the velour grafts was most like that of the normal aorta. The velour graft appears to develop the least thrombogenic neointimal surface while becoming most frequently healed with a cellular neointimal surface. 相似文献
92.
Papas S Crépel V Hasboun D Jorquera I Chinestra P Ben-Ari Y 《The European journal of neuroscience》1992,4(8):758-765
In vivo and in vitro techniques were utilized to examine the influence of a protein synthesis blocker, cycloheximide (CHX), on the damaging effects of anoxia in the rat. CHX administered 1 h before transient (30 min) forebrain ischaemia increased the survival of animals, decreased body weight loss and reduced the occurrence of delayed degeneration in the CA1 pyramidal region. The same dose of CHX injected 1 h after ischaemia induced status epilepticus, a decrease in survival rate, and did not reduce weight loss or CA1 damage in any of the surviving rats. Electrophysiological techniques were then used to determine the effects of various periods of anoxia and aglycaemia (AA) on CA1 field excitatory postsynaptic potentials (EPSPs) in hippocampal slices incubated in the presence or absence of CHX. In CHX-treated slices, recuperation of EPSP amplitude (45±16%) was significantly greater than in control slices (9±9%) following an AA episode of 3 min 45 s. No difference was seen in the percent recuperation of EPSPs in the control and CHX-treated slices after shorter or longer episodes of AA. From these studies, it appears that CHX protects against the damaging effect of ischaemia in vivo or AA in vitro. 相似文献
93.
R. Papeschi 《Psychopharmacology》1977,55(1):1-7
Behavioral data are reviewed that give evidence for an indiscriminate involvement of brain catecholamines (CA), especially dopamine (DA), in nervefunction, regardless of the time elapsed from their synthesis. Critical analysis of biochemical and pharmacological studies shows that a clear-cut distribution of brain catecholamines in two compartments [newly synthesized (NS) and main storage] is not at all established, and moreover that there is no adequate proof that the difference in turnover rates attributed to these two supposed pools is due to a preferential extraneuronal release of NS-CA during nerve function rather than to a preferential (nonfunctional) intraneuronal deamination of NS-CA, or at least of NS-DA. 相似文献
94.
Komai S Matsuyama T Matsumoto K Kato K Kobayashi M Imamura K Yoshida S Ugawa S Shiosaka S 《The European journal of neuroscience》2000,12(4):1479-1486
We found that neuropsin, an extracellular matrix serine protease, has a regulatory effect on Schaffer-collateral long-term potentiation (LTP) in the mouse hippocampus. Bath application of 1-170 nM recombinant neuropsin modulated early phase LTP in the Schaffer-collateral pathway with a 'bell-shape' dose-response curve. The maximum enhancing activity (134% of control LTP) was found at approximately 2.5 nM. Bath application of a neutralizing antibody against neuropsin in the hippocampal slice resulted in a marked inhibition of the tetanus-induced early phase of LTP. The in vivo continuous intraventricular infusion of an antisense oligonucleotide against neuropsin significantly reduced the amplitude of the tetanus-induced early phase of LTP in vitro. Neuropsin did not directly change the N-methyl D-aspartate (NMDA) current. Thus, neuropsin appears to act as a regulatory molecule in the early phase of LTP via its proteolytic function on extracellular matrix rather than affecting NMDA receptor-mediated calcium increase. 相似文献
95.
对子宫腺肌病患者血清CA125及EMAb的临床评价 总被引:15,自引:0,他引:15
目的:探讨血清CA125及子宫内膜抗体(EMAb)测定,对子宫腺肌病的诊断及疗效评估的临床价值。方法:经术后病理学检查确诊子宫腺肌病患者63例和子宫肌瘤患者45例,均于术前及术后测定两组血清CA125水平和EMAb。结果:子宫腺肌病组术前血清CA125平均水平及EMAb阳性率均高于子宫肌瘤组,两者相比差异有显著性(P<0.001及P<0.01)。联合测定血清CA125水平和EMAb,以两者均阳性为诊断标准,诊断子宫腺肌病的敏感性为54.63%,特异性为100%。子宫腺肌病组术后血清CA125水平和EMAb阳性率均较术前下降,差异有显著性(P<0.01及P<0.05)。结论:测定血清CA125及EMAb对子宫腺肌病有较好的辅助诊断价值,联合检测更能提高诊断的正确性,并可作为评价子宫腺肌病疗效的敏感指标。 相似文献
96.
血清CA125检测在子宫内膜癌中的价值 总被引:3,自引:0,他引:3
目的探讨血清CA125在子宫内膜癌中的价值.方法选取1992年3月~2002年3月在北京大学第一附属医院、北京大学人民医院住院经手术治疗的子宫内膜癌患者141例,术前及随访中用放射免疫法测定血清CA125水平,CA125≥35 U/ml 为阳性结果.对其中14例行子宫内膜癌组织CA125免疫组化方法检测.收集患者的临床病理资料,分析CA125与这些资料的关系以及复发患者复发前后CA125变化.结果 CA125免疫组化检测14例均呈阳性,阳性细胞着色率与血清CA125之间无明显相关.141例患者术前血清CA125阳性32例(22.7%), Ⅰ、Ⅱ、Ⅲ和Ⅳ期患者血清CA125阳性(阳性率)分别为11例(12.1%)、6例(31.6%)、12例(46.2%)和3例(60.0%). 血清CA125阳性率随子宫内膜癌期别的增加而升高.深肌层浸润、宫颈受累、附件转移、腹腔洗液细胞学阳性、盆腔淋巴结转移及宫内肿瘤病灶≥2 cm者,血清CA125阳性率增加.随访中13例复发,其中9例术前血清CA125>35 U/ml者复发时均伴血清CA125水平升高,而另4例术前血清CA125正常者,复发后血清CA125水平仍正常.结论子宫内膜癌患者术前血清CA125的测量有助于了解肿瘤的侵犯范围.术前血清CA125水平异常的子宫内膜癌患者,术后定期复查血清CA125水平,将有助于子宫内膜癌病情的监测. 相似文献
97.
98.
卵巢癌患者TPS与CA125测定 总被引:1,自引:0,他引:1
[目的]探讨卵巢上皮性癌患者组织多肽特异抗原(tissue polypeptide specificantigen,TPS)与CA125水平测定及其临床意义.[方法]采用ELISA法和EIA法分别检测96例卵巢上皮性癌患者和33例妇科良性疾病患者血清TPS与CA125水平并进行比较分析.[结果]Ⅲ Ⅳ期卵巢上皮性癌患者血清TPS和CA125平均水平及阳性率均高于Ⅰ Ⅱ期(P<0.05),治疗有效组TPS和CA125水平显著低于初诊未治组,而复发转移组TPS水平明显高于初诊未治组.[结论]TPS与CA125水平的联合检测对卵巢癌诊断、疗效及预后有临床应用价值. 相似文献
99.
N. P. KOPER L. F. A. G. MASSUGER C. M. G. THOMAS L. A. L. M. KIEMENEY C. P. T. SCHIJF L. V. A. M. BEEX & A. L. M. VERBEEK 《International journal of gynecological cancer》1997,7(2):127-133
Serum CA125 concentrations measured before and during chemotherapy may provide additional information for prognostic assessment of patients with epithelial ovarian cancer (EOC), and enable discrimination between patients who are likely to benefit from further therapy and those who will not. Medical records of 40 patients with advanced EOC, treated at the Department of Obstetrics and Gynecology of the University Hospital Nijmegen between July 1984 and April 1993, were examined. All patients had primary cytoreductive surgery followed by platinum-based chemotherapy. Serum samples were obtained before surgery and during chemotherapy. Follow-up information and patient and tumor characteristics were abstracted from medical records until December 1, 1994. By using multivariate Cox proportional hazards models for disease-free and overall survival it was evaluated whether outcome prediction was improved by inclusion of serum CA125 quantitations.
Only FIGO stage and extent of residual tumor were significant independent prognostic factors before the start of chemotherapy. When such regression models were constructed after subsequent courses of chemotherapy, serum CA125 measurements conducted after each of the first three chemotherapy courses improved the prediction of disease-free survival. Prediction of overall survival was improved by inclusion of serum CA125 measurements after courses 1–6. Inclusion of serum CA125 measurements during chemotherapy improved prognostic assessment of patients with advanced EOC. 相似文献
Only FIGO stage and extent of residual tumor were significant independent prognostic factors before the start of chemotherapy. When such regression models were constructed after subsequent courses of chemotherapy, serum CA125 measurements conducted after each of the first three chemotherapy courses improved the prediction of disease-free survival. Prediction of overall survival was improved by inclusion of serum CA125 measurements after courses 1–6. Inclusion of serum CA125 measurements during chemotherapy improved prognostic assessment of patients with advanced EOC. 相似文献
100.
Toru Sugiyama Takashi Nishida Akio Kataoka Kan Komai Naofumi Ookura Toshio Oobuchi Michiaki Yakushiji 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):92-96
Background We investigated retrospectively the records and tissue samples of patients with primary ovarian transitional cell carcinoma
to determine clinical and pathologic features.
Methods The records of 3 patients with ovarian transitional cell carcinoma were reviewed using data from several imaging techniques:
transvaginal ultrasound, computed tomography, and magnetic resonance imaging. We also determined levels of several tumor marker
molecules; and the level of carbohydrate antigen 125 (CA 125), was examined by means of immunohistochemistry.
Results The tumors of 2 patients were classified as pure trnasitional cell carcinoma; in the remaining patient, as predominantly transitional
cell carcinoma. All tumors were bilateral, and 2 of the 3 tumors formed solid masses. Areas of irregular high intensity signals
were seen in magnetic resonance images of the solid parts of the tumors. All 3 tumors tested positive for CA 125; histochemical
expression was confined to the tumor cell membrane and/or the cytoplasm in all cases. The tumors of all 3 patients tested
negative for carcinoembryonic antigen (CEA), and second-look laparotomies did not reveal any residual neoplasms in any of
the patients. The patients have been in a disease-free state for 34, 42, and 14 months, respectively.
Conclusion Our results suggest that transitional cell carcinomas tend to arise bilaterally and to form solid tumors. Magnetic resonance
imaging was a useful diagnostic modality in these cases. Transitional cell carcinoma was characterized by the presence of
CA 125 and the absence of CEA. 相似文献