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991.
992.
993.
Predicting failure in polytetrafluoroethylene vascular access grafts for hemodialysis: a pilot study
C R Shackleton D C Taylor A R Buckley V A Rowley P L Cooperberg P D Fry 《Canadian journal of surgery》1987,30(6):442-444
In order to determine if serial, noninvasive evaluation of polytetrafluoroethylene (PTFE) vascular access grafts could identify a subgroup of patients at risk for thrombosis, the authors studied flow characteristics, using duplex ultrasonic scanning, in 18 hemodialysis patients with forearm loop grafts. On average, five examinations were performed per patient over the 10-month study period. Seven episodes of thrombosis occurred in six patients. The mean Doppler flow in grafts that subsequently thrombosed was significantly lower than in those that did not (544 +/- 218 ml/min versus 843 +/- 391 ml/min, p less than 0.001). The interval from last examination to thrombosis ranged from 13 to 58 days. At a defined cut-off flow of 450 ml/min, this test yielded a sensitivity of 83% and a specificity of 75% for episodes of thrombosis occurring within 2 to 6 weeks. The authors conclude that episodes of thrombosis in PTFE arm loop grafts are usually preceded by significantly lower Doppler-measured flow than grafts that do not thrombose and that it may be possible, by this means, to identify grafts at risk. 相似文献
994.
M Aschner 《Pharmacology & toxicology》1987,60(2):81-85
It was established by means of SDS polyacrylamide gel electrophoresis that direct injections of methyl mercury (10 micrograms Hg) into the mature rat vitreous body of the eye decrease protein synthesis in the retina and optic nerve at 4 hours after injection. Although the global spectrum of polypeptides did not change, a specific decrease in the volume of polypeptides of 20-23 K daltons molecular weight was evident. Conversely, systemic exposure to methyl mercury resulted in increased protein synthesis of polypeptides of 20-23 K molecular weight both in adult (8 mgHg/kg/day for 8 days) and neonatal rats (2 mgHg/kg/day for 10 days). In addition, specific changes in the volume of polypeptides 75-90 K molecular weight were noted in sciatic nerves of neonatal rats. These data are consistent with a bimodal response in protein synthesis following MeHg treatment. Local presence of MeHg following direct injection into the eye causes a reduction in protein synthesis, while chronic systemic exposure results in increased synthesis and transport of proteins in both mature and developing optic nerves and neonatal sciatic nerves. Thus, these systems possess the capacity to attempt regenerative processes through induction of a small subset of proteins known as GAPs (Growth-Associated Proteins) during the early stages of systemic methyl mercury exposure. These wide spread and system-specific changes are consistent with growth-specific functions during the early stages of methyl mercury exposure. 相似文献
995.
N Watanabe Y Niitsu H Umeno H Kuriyama H Neda N Yamauchi M Maeda I Urushizaki 《Gan to kagaku ryoho. Cancer & chemotherapy》1987,14(12):3337-3343
Effects of human recombinant TNF on the tumor blood vessels and on the thrombus formation were investigated in relation to its mode of antitumor action against Meth-A sarcoma transplanted in BALB/c mice. The extent of the blood vessel lesion was evaluated by using transparent chamber placed in the mouse skin. Bleeding, hyperemia and congestion were observed at 1-2h, 4-6h and 24h after TNF (1 X 10(4)U/mouse) administration, respectively. In contrast, no histological changes in the normal blood vessels were observed microscopically following TNF injection. Thrombus formation was evoked in the tumor vessels 4h after TNF injection. However, when thrombus formation was prevented by heparin, no difference was observed among antitumor action of TNF against Meth-A fibrosarcoma necrotic response and the rate of complete cure. These results suggest that the direct effects of TNF causing lesions in the tumor blood vessels plays an important role in its antitumor action. 相似文献
996.
F Mandelli G De Rossi P Mancini A Alberti A Cajozzo F Grignani P Leoni V Liso M Martelli A Neri 《Journal of clinical oncology》1987,5(3):398-406
Clinical and biological data were evaluated using Desu univariate analyses or Cox multivariate analyses in a series of 1,777 chronic lymphocytic leukemia (CLL) patients from an Italian Cooperative Group. In univariate analyses, age and sex of patients, presence of bone marrow (BM; greater than or equal to 50%), and peripheral blood (PB; greater than or equal to 60,000/microL) lymphocytosis, anemia (hemoglobin [Hb] less than 11 g/dL), thrombocytopenia (less than 100,000/microL), direct Coombs' test positivity, hepatomegaly, splenomegaly, and extent of lymph node involvement were shown to be of significant prognostic value. Multivariate analyses, through a stepwise procedure, showed that the most important prognostic variables are Hb, hepatomegaly, lymph node involvement, PB lymphocytosis, and age and sex of patients. Further covariates would produce an improvement having a nonsignificant P value. Based on the results of multivariate analyses, a four-step staging using the significant variables of the Cox model is proposed. 相似文献
997.
The records of 29 consecutive patients treated by a pure, open, anterior acromioplasty were reviewed retrospectively. Excluded from consideration were patients with the following pathologic diagnoses or histories: (1) previously attempted acromioplasty on the same shoulder; (2) intraoperatively confirmed rotator cuff tear; (3) any surgically treatable biceps tendon or acromioclavicular abnormality; (4) lost to follow-up study. Three different techniques were employed to perform the acromioplasties. The first technique required partial deltoid origin detachment with an osteotome. The second technique spared the deltoid origin, while again using an osteotome to perform the acromioplasty. The third technique also spared the deltoid origin but used a high-speed burr to perform the acromioplasty. Evaluated in terms of patient satisfaction, residual pain, length of convalescence, suboptimal results, and complications, the first technique proved to be the least effective. The second technique produced early, excellent results. The third technique, in which a burr was employed through an intact deltoid origin, was most effective; technically, the method was also relatively simple and reliable. 相似文献
998.
999.
S. MD. Iqbal A. K. Garg C. M. Kalaiah 《Indian journal of otolaryngology and head and neck surgery》1987,39(1):38-39
A case of Goldenhar’s Syndrome in a 10 year old girl is reported. The unusual features are the absence of epibulbar dermoid which is one of the major hallmarks of the Syndrome and the presence of an associated Cyanotic Heart disease. 相似文献
1000.
The present paper deals with a Finnish long-term prospective study, the objective of which is to shed light on adjustment to retirement and old age. In this phase, only the preliminary findings of the initial survey carried out in 1982 are available. For the purposes of the study, a random sample of 200 individuals was drawn from among Turku inhabitants born in 1920. Another sample, consisting of 189 persons of the same age, was drawn from rural municipalities in the neighborhood of Turku. An extensive structured psychosocial interview could be conducted with a total of 339 subjects. The research methods used included e.g. the 36-item version of Goldberg's General Health Questionnaire (GHQ). Relatively little mental disturbance was revealed in the interview, and no major differences occurred between the urban and the rural sample. Somewhat over one-third of both samples were probable psychiatric cases as defined according to the GHQ. 相似文献