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51.
Under study was the efficacy of three schedules of dose fractionation in intracavitary gamma-therapy in cervical cancer patients treated on the machine "AGAT-B". Single doses were 1000, 700 and 500 rad, while total dosage at point A depending on the stage of the disease was within the range of 4000-5000 rad. The survival during the first, second and third years following termination of the radiotherapy was found to be identical for patients of all the groups under examination. No differences were noted in them also in the character of early radiation reactions on the part of the adjacent organs. The frequency and severity of late radiation injuries of the urinary bladder, rectum and vagina were related to the dose fractionation regimen. 相似文献
52.
Fuerhacker M Haile TM Kogelnig D Stojanovic A Keppler B 《Water science and technology》2012,65(10):1765-1773
This paper presents the results of adsorption studies on the removal of heavy metals (Cr, Cu, Cd, Ni, Pb and Zn) from standard solutions, real wastewater samples and activated sewage sludge using a new technique of liquid-liquid extraction using quaternary ammonium and phosphonium ionic liquids (ILs). Batch sorption experiments were conducted using the ILs [PR4][TS], [PR4][MTBA], [A336][TS] and [A336][MTBA]. Removal of these heavy metals from standard solutions were not effective, however removal of heavy metals from the industrial effluents/wastewater treatment plants were satisfactory, indicating that the removal depends mainly on the composition of the wastewater and cannot be predicted with standard solutions. Removal of heavy metals from activated sludge proved to be more successful than conventional methods such as incineration, acid extraction, thermal treatment, etc. For the heavy metals Cu, Ni and Zn, ≥90% removal was achieved. 相似文献
53.
Bypass surgery for vascular disease of the carotid system 总被引:2,自引:0,他引:2
TM Sundt RG Siekert DG Piepgras FW Sharbrough OW Houser 《Canadian Metallurgical Quarterly》1976,51(11):677-692
A series of 58 operations on 56 patients, in whom a branch of the superficial temporal artery was anastomosed to a branch of the middle cerebral artery (STA-MCA bypass or Yasargil procedure), is reviewed. These operations were performed chiefly for occlussions or for inaccessible stenotic lesions of the internal carotid or middle cerebral arteries. Patency in eight patients operated on from April 1971 through November 1973 was low (25%). Patency in patients operated on since July 1974 has been high (95%). There have been no deaths and no major ischemic strokes attributable to the surgery. The rationale for this procedure is considered in relationship to the anatomy and physiology of the cerebral circulation and the pathogenesis of syndromes of cerebral ischemia. The operation appears to have a low morbidity in good-risk patients. The role of this operation in managing common manifestations of cerebral vascular disease such as focal transient cerebral ischemic attacks (TIAs) and amaurosis fugax, although not fully established, appears encouraging. The procedure seems useful for orthostatic cerebral ischemia caused by multiple occlusions of major extracranial (and intracranial) vessels and, occasionally, for progressing strokes related to internal carotid artery occlusion, both of which are relatively uncommon manifestations of cerebral vascular occlusive disease. It may have application in the rare "slow stroke." The procedure is probably of limited value, if any, in the management of large completed infarcts but may be indicated in selected patients with small infarctions who have preserved most of their cerebral function and who have had evidence of subsequent focal ischemic events. The procedure is useful for bypassing giant aneurysms or basofrontal tumors invading major vessels. It may have a role in the management of fibromuscular disease of the internal carotid artery. 相似文献
54.
The influence of surgical stress on resistance to i.v. challenge with Walker 256 tumour cells was investigated in rats, with respect to the functional state of the reticuloendothelial system (RES). Phagocytic activity of the RES was evaluated by colloid (gelatinized [131I] "RE test lipid emulsion") clearance, and opsonin levels were determined by bioassay. Reticuloendothelial clearance capacity was significantly (P less than 0-05) depressed 60 min following surgery (coeliotomy plus jejunal enterotomy) as quantified by both humoral and cellular parameters of RE function. Phagocytic depression was primarily due to impaired hepatic Kupffer cell function and related to a deficiency in the phagocytic supporting capacity of plasma, also referred to as opsonic or recognition factor (RF) capacity. During the postoperative period of RES colloid clearance depression, pulmonary localization of the blood-borne test particulate matter increased. Rats challenged with 51Cr-labelled viable tumour cells at a dose of 1-0 X 106 i.v., either prior to or during the postoperative period of RE depression, manifested a significant (P less than 0-05) increment in pulmonary localization of the viable tumour cells, and a decrease (P less than 0-05) in hepatic clearance. Evaluation of survival patterns demonstrated a significant (P less than 0-01) decrease in host resistance to i.v. tumour cell challenge (2 X 103 cells) during the postoperative period of RE depression and hypo-opsonaemia. Sham-anaesthetized control animals survived 17-9 +/- 0-8 days, while animals challenged during the period of RE depression survived 7-9 +/- 0-4 days. An increased incidence of respiratory distress and nasal discharge was observed in the animals with impaired survival. Thus, surgical manipulation may transiently compromise RES systemic host defence and may be reflected in an increment in the pulmonary localization of blood-borne tumour cells. The relationship of this altered pattern of tumour cell distribution to the impaired survival remains to be determined, and warrants investigations. 相似文献
55.
Characterization and microstructure of highly preferred oriented lead barium titanate thin films on MgO (100) by sol-gel process 总被引:1,自引:0,他引:1
Highly preferred oriented lead barium titanate (Pb1−x,Bax)TiO3 thin film, with particular emphasis on (Pb0.5,Ba0.5)TiO3, can be obtained by spin-coating on MgO (100) substrate by using the precursor sol, which was synthesized from acetylacetone chelating with titanium isopropoxide and ethylene glycol as a solvent, in the sol-gel process. Film thickness, pyrolysis temperature and heating rate were studied systemically to investigate their influences on the formation of preferred oriented thin films. The highly preferred (001)/(100) oriented thin film could be obtained by the pyrolysis of wet film at 500 °C and annealing at 600 °C at a slow heating rate of 5 °C/min. It is confirmed that the tetragonal perovskite structure of the titanate ceramic decreases with an increase of Ba content in (Pb1−x,Bax)TiO3. The (001)/(100) oriented films were synthesized from all compositions between x = 0.2 and x = 0.8, at a crystallization temperature of 600 °C. In particular, for the Ba content in the range of x = 0.50.6, highly preferred (001)/(100) planes were observed. 相似文献
56.
TM Lovell RT Gladwell FJ Cunningham NP Groome PG Knight 《Canadian Metallurgical Quarterly》1998,139(3):1164-1171
Accumulating evidence implicates inhibins and activins as endocrine and local regulators of follicular development in mammals, and it was recently confirmed that inhibin/activin alpha and betaA genes are also expressed in the avian ovary. To investigate the potential involvement of these proteins in the chicken ovary, thecal and granulosa layers of the four largest follicles (F1-F4) and the most recent postovulatory follicle were collected from hens (10/group) killed 4, 12, and 20 h before the expected time of F1 ovulation. Inhibin A and activin A concentrations of tissue extracts (expressed per mg DNA) were measured using validated two-site enzyme-linked immunosorbent assays; total immunoreactive inhibin alpha-subunit (ir-alpha) was also measured by heterologous RIA (Monash assay). Inhibin A and ir-alpha were largely confined to the granulosa layer, whereas activin A was much more abundant in the thecal layer. Granulosa inhibin A contents were similar in F4 and F3, but increased approximately 40-fold from F3-F1 (P < 0.0001). As such, the F1 granulosa layer was by far the richest source of inhibin A in the chicken ovary, but contained very little activin A. Total ir-alpha in granulosa was much more abundant than inhibin A and increased only 3-fold from F4-F1 (P < 0.001). Activin A in both granulosa and theca showed little variation between F1 and F4 follicles (by ANOVA, P > 0.05). The inhibin A content of F1 granulosa was maximal 12 h before ovulation and had fallen approximately 6-fold (P < 0.0001) within 8 h, suggesting an inhibitory effect of the preovulatory LH surge on the F1 capacity to synthesize inhibin A. Inhibin A, activin A, and ir-alpha were all less in the postovulatory follicle compared with F1 before ovulation (P < 0.0001). In conclusion, application of the present two-site enzyme-linked immunosorbent assays to the chicken ovary revealed 1) divergent tissue distribution of inhibin A and activin A within preovulatory follicles, and 2) differential regulation of granulosa cell production of inhibin A and activin A dimers during preovulatory follicular development. These findings of dynamic changes in inhibin A, activin A, and total ir-alpha support the hypothesis that these proteins subserve regulatory roles during preovulatory follicular development in the hen. 相似文献
57.
为提高西红柿红外干法去皮的加工性能,本研究建立了红外辐射加热的三维传热模型,利用该模型对西红柿红外去皮过程中表面和内部不同位置的温度进行预测,并通过比较温度预测值和实测值来验证模型的拟合度;进一步通过能耗计算对比分析两种不同的红外设备,筛选出较优的红外设备。结果表明,与静态催化红外设备相比,燃气-滚轮传送式催化红外设备可以实现对西红柿表皮的快速加热(表面最高温度为60.32℃),且西红柿表面温度分布更均匀(最大温差约6.44℃);内部温度增幅较低(内部最高温度为49.10℃),且内部温度分布也较均匀(最大温差约18.25℃)。模型预测值与实测值之间的拟合较好(R2≥0.93),且两者之间的估计标准误差EESE值较低(0.13~10.80℃),表明三维传热模型的拟合效果良好,能够很好地反映不同红外设备下西红柿表面和内部的温度分布。与静态式催化红外设备相比,燃气-滚轮传送式催化红外设备更优,即缩短了16.60%的加工时间,又节约了34.80%的能耗,更高效节能,在果蔬去皮领域具有广阔的应用前景及工业化推广价值。 相似文献
58.
采用多频超声波技术对菜籽油的酶法(磷脂酶A1)脱胶效果及其脱胶后油品质变化展开了相关研究。结果表明,多频超声波作用能有效地提高磷脂酶A1对菜籽油的脱胶效率,大幅度降低脱胶后菜籽油中的含磷量;并且20/50 kHz双频超声处理对菜籽油的脱胶效果最佳。与磷脂酶A1脱胶后菜籽油相比,超声波作用后的脱胶油酸价和过氧化值略有上升(均在国家标准所规定的安全范围内),色泽变浅,脂肪酸组成的数值变化不明显。 相似文献
59.
脱脂小麦胚芽蛋白分类及其氨基酸组成分析 总被引:7,自引:2,他引:7
对脱脂小麦胚芽蛋白进行Osboren分类研究,进一步研究了各蛋白组分的亚基分子质量分布、氨基酸组成和营养价值.试验结果表明,球蛋白和清蛋白是小麦胚芽蛋白的主要组分.SDS-PACE分析中,清蛋白主要亚基分子质量为15 000、17 400、20 500、29 000、33 400~37 100和54 900 u.球蛋白主要亚基分子质量为12 300、20 000、23 500、36 000~40 100和47 000~55 200 u,谷蛋白的主要亚基分子质量为55 000、41 800和<27 000 u.同时,试验结果也表明,清蛋白的氨基酸评分最高,其次分别为谷蛋白、球蛋白和醇溶蛋白;清蛋白具有最高的蛋白质效率比(PER)和体外消化率(IVPD),醇溶蛋白和谷蛋白的PER和IVPD较小;清蛋白的蛋白质消化率校正的氨基酸记分法(PDCAAS)最高,球蛋白、醇溶蛋白和谷蛋白的PDCAAS较小.因此,与FAO/WHO模式相比,清蛋白具有较好的氨基酸组成和PDCAAS,是一种优质蛋白质. 相似文献
60.