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61.
An increasing number of hepatic resections are being performed as potentially curative surgery for malignant liver neoplasms. Hepatectomy and subsequent liver regeneration produce a local environment that enhances growth of microscopic residual tumor. To determine if pretreatment with murine interferon gamma (IFN-gamma) can protect against such enhanced tumor growth, Buffalo rats were randomized to receive a 3-day treatment of IFN-gamma (50,000 U/qD intraperitoneally) or saline. Groups then underwent intrasplenic injection of 10(6) Morris hepatoma cells, followed 1 hour later by sham (control) or partial hepatectomy (PH) of 70%. PH significantly enhanced tumor growth within the liver (control, 8 +/- 3 nodules per liver; PH, 73 +/- 12 nodules per liver; P < .001). This enhancement was attenuated by prior administration of IFN-gamma IFN-gamma/PH, 16 +/- 3; P < .001 vs. PH). Growth factor release and liver regeneration were not affected significantly by pretreatment with IFN-gamma. The effect of IFN-gamma on tumor growth is associated with a significant enhancement of Kupffer cell (KC)-mediated tumoricidal activity (percentage of specific lysis, 55 +/- 10% control, 78 +/- 11% IFN-gamma, P < .01) but not lymphocyte-mediated tumoricidal activity. Because microscopic residual disease may be present after hepatectomies for cancer, IFN-gamma may be useful agent in retarding growth of residual tumors. 相似文献
62.
HM Hayes 《Canadian Metallurgical Quarterly》1976,104(6):673-677
Significantly reduced immunoglobulins were found in 22 patients with phenylketonuria. Tests of cellular immune function which included delayed skin hypersensitivity, T rosettes and PHA transformation were normal. Escherichia coli antibodies and the booster response to tetanus toxoid were also normal. 相似文献
63.
53 patients clinically suspected of having a cerebellopontine angle (CPA) lesion were examined by computer tomography (CT) with 160 X 160 matrix EMI scanner. 17 cases (32%) had tumour positive CT, of which 12 were neurinomas and 1 meningioma. 1 CT suggestive of a CPA lesion was false positive and 1 unoperated case is probably a false negative CT. Three of the eleven verified neurinomas (27%) were of the medial type originating in the angle cistern. One neurinoma protruding 1 cm into the cistern showed no contrast enhancement. 2 CT scans (3.8%) were unsatisfactory due to movements and the large size of the head. CT is valuable for the investigation of CPA pathology and the diagnostic efficiency compares favourably to other neuroradiological procedures. 相似文献
64.
Ss discussed topics with an interviewer (I) whose comments were controlled by a motor response made by S. In Exp. I, there was less increase in silence over trials, more negative attitude toward the I, and longer delay after I responses when these were interpretations rather than reflections. With a choice between interpretation and reflection, several personality differences were found between Ss preferring one rather than the other of the two classes of I response. Ss in Exp. 1 requested an I response less frequently when he disagreed with them, but only under conditions in which Ss were told the I would try to influence them. Under influence instructions there was a positive correlation between frequency of I responses and negative attitude toward him. In Exp. 3, frequency of I response was maintained over trials only for Ss high on the Social Desirability Scale. The attitude of high SD Ss was more negative when emotional, rather than neutral, topics were discussed. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
66.
Reviews the generally low correlations of graduate record examination (gre) general aptitude scores with various criteria of performance in graduate school. A retrospective study of phd's from 1 university is also reported, relating gre scores to postdoctoral publication records. Correlations were statistically zero (.02-.24), computed in several ways for both clinical and nonclinical graduates. A national review of the use of the gre for screening is suggested in light of its apparent effectiveness as an obstacle for the admission of minority students. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
67.
D. C. Youla J. D. Rhodes P. C. Marston 《International Journal of Circuit Theory and Applications》1973,1(1):59-70
In the light of several recent theoretical breakthroughs1,2 it appears reasonably certain that the insertion-loss synthesis of a broad class of practical lumped-distributed filters will soon become a reality. In particular, the structure of filters composed of a finite cascade of lumped reactive 2-ports and equidelay ideal TEM lines is now almost completely understood and the related approximation problem not only seems soluble but also amenable to digital computer implementation. The advances in References 1 and 2 were sparked by a remarkable counter-example due to Rhodes and Marston3 and it is the purpose of the present summary to give a complete discussion and account of the concrete gains made up to this point without, of course, entering into proofs of material already published. Briefly, the order of ideas is as follows. In Reference 1 a fundamental synthesis theorem is established with the aid of the 2-variable positive-real concept and in Reference 2 explicit formulae are derived for the various junction reflection coefficients. In addition, Reference 2 reformulates the synthesis theorem in Reference 1 and succeeds in removing the 2-variable positive-reality requirement but only at the expense of introducing two extra conditions of the 1-variable type. Theorem 2 of the present note succeeds in eliminating the more complicated of these two conditions and has as consequence the final and definitive ‘Strong Theorem 1’. A full proof of theorem 3 is given in the Appendix and one illustrative example is worked out in detail. 相似文献
68.
Fifty-nine Fischer rat tumors and eleven Hooded rat tumors induced by intramuscular injection of Ni3S2 were examined and their histopathologic and cytologic characteristics studied. Nine out of eleven Hooded rat tumors metastasized whereas 15 out of 59 Fischer rat tumors metastasized within 30 days. Histopathological characterization of the Ni3S2-induced tumors was made according to their preponderant cellular constitution. They were grouped into six types: well-differentiated rhabdomyosarcomas, poorly-differentiated rhabdomyosarcomas, embryonal rhabdomyosarcomas, mesenchymal tumors, leiomyosarcoma-like tumors and fibrosarcoma-like tumors. Forty-seven of total of 70 were rhabdomyosarcomas. Tumors with shorter latent periods in Fischer rats and tumors with fleshy and soft texture demonstrated a higher incidence of metastases. 相似文献
69.
HM Agrama JM Blackwood CS Brown GW Machiedo BF Rush 《Canadian Metallurgical Quarterly》1976,132(3):418-421
Various types of drains were inserted into the peritoneal cavity of twenty-eight dogs. After one to seven days, all drains failed to show the presence of 200 cc of colored fluid injected intraperitoneally. On autopsy, all tubes were surrounded and occluded by omentum. 相似文献
70.
A histopathologic study of macular cysts and holes 总被引:1,自引:0,他引:1
Forty-four eyes from 39 patients with either lamellar macular holes (17 eyes), full-thickness macular holes (18 eyes), and/or macular cysts (9 eyes) were studied histopathologically. Lamellar and full-thickness holes were frequently found in eyes with a history of trauma or ocular surgery. Diabetes mellitus was the most common condition associated with macular cysts. Four lamellar holes and four full-thickness holes occurred in eyes with senile macular degeneration. Six lamellar holes, eight full-thickness holes, and one macular cyst developed on an idiopathic basis. Residual cystoid macular edema was the most prevalent accompanying pathologic feature. Cystoid macular edema was also noted in the opposite eye in seven cases of lamellar and full-thickness holes. A preretinal glial membrane, thought to be a secondary change, was found at or near the edges of the lamellar or full-thickness holes or over the macular cyst in the majority of cases. Wrinkling of the internal limiting membrane (ILM) was present in five cases. Vitreous traction, with or without an operculum, was infrequently associated with these entities. 相似文献