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991.
Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA 总被引:13,自引:0,他引:13
Y. Ueno K. Iijima S.-D. Wang Y. Sugiura M. Sekijima T. Tanaka C. Chen S.-Z. Yu 《Food and chemical toxicology》1997,35(12):1143-1150
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis. 相似文献
992.
B. Shen MD Z. Younossi MD B. Dolmatch MD J. Newman MD M. Henderson MD J. Ong MD T. Gramlich MD M. Yamani MD 《The American journal of gastroenterology》2000,95(9):2607-2607
993.
栓线法大鼠局灶性脑缺血模型的研究 总被引:29,自引:0,他引:29
采用颈部旁侧手术入路,结扎右侧颈总动脉、颈外动脉及其分支后颈内动脉栓线法制作大鼠大脑中动脉闭塞再灌流损伤模型。闭塞成功率94.1%,动物偏瘫症状评分在缺血2h再灌流3d后趋于稳定,病理改变以尾壳核损害最重。再灌流7d脑梗塞体积为97.8±9.4mm3,动物死亡率59.4%。缺血2h后再灌流先出现过渡灌注,而后呈持续性低灌注。本文模型勿需开颅,缺血效果可靠,对局灶性脑缺血的研究具有实用价值。 相似文献
994.
995.
K E Wallner D Nori M J Morse P C Sogani W F Whitmore Z Fuks 《The Journal of urology》1990,144(3):704-706
We treated 13 patients with a second 125iodine implant for local recurrence of prostatic carcinoma. All patients had biopsy proved palpable recurrence without evidence of distant metastases. Full doses of irradiation were used (median matched peripheral dose 170 Gy.). Six patients had complete regression of palpable recurrence, 2 had partial regression, 2 had no apparent response and 3 were unevaluable for local response. Actuarial freedom from local disease progression at 5 years was 51%. Despite a relatively high rate of local disease control the actuarial rate of distant metastases reached 100% at 6 years after reimplantation. There were 2 severe rectal complications and 4 instances of mild to moderate urinary incontinence among the 13 patients. Local regression of recurrent prostatic carcinoma may be achieved with 125iodine reimplantation but most patients still had distant metastases. 相似文献
996.
Correction of the position of the limbus in open reduction of congenital hip dislocation in children
On the basis of their clinical experience in the treatment of 146 patients with congenital dislocation of the hip the authors have evaluated the state of the limb in this pathologic condition. Various changes in the limb's form have been observed depending on the expression of the hip dislocation and on the patient's age. The instruments for incisions and for correcting the limb's position have been worked out. The fixation of the limb in the functionally correct position is carried out by stitching its fragments and fixing the strained threads in the greater trochanter area. The correction of the limb's position allows the subsequent correct development of the acetabular roof. 相似文献
997.
998.
In vivo 19F NMR at 4.7 T has shown that the biphasic elimination of the vapor anesthetic isoflurane from rat brain is ca 15% slower in old (23-24 months) animals compared with young (5-6 months) animals. The fast kinetic component has a t1/2 of ca 7-9 min and the slow event, 100-115 min. Gas chromatographic measurement of arterial blood elimination displays age attenuation to the same extent, although a monophasic kinetic process (6-7 min). The slow wash-out from brain is thought to involve elimination from intracranial fatty tissue as postulated by others in rabbit brain. Longitudinal relaxation time measurements show monoexponential recovery and essentially identical values for young (1.09 + 0.11 s) and old (1.04 +/- 0.09 s) animals. For dipalmitoylphosphatidylcholine vesicles the monoexponential recovery also suggests rapidly exchanging averaged homogeneous lipid environments for the anesthetic, but the longer T1s (2.75 +/- 0.25 s) imply less restricted mobility compared with brain. Single T2 values were obtained in vivo, indicating either a single compartment or rapid exchange between multiple environments. These measurements were inconsistent, undoubtedly as a result of B1 inhomogeneity. The age-attenuated elimination kinetics for isoflurane are consistent with poorer cardiopulmonary function, whereas the T1 data suggest similar environments for the anesthetic in young and old brain tissue. 相似文献
999.
Neuronal dense-core vesicles provide a mechanism whereby peptide messengers are secreted in discrete quanta. Here we report on the capacity of rat hypophysiotrophic corticotropin releasing factor-41 neurons to alter the peptide content as well as the size of dense-core vesicles after removal of glucocorticoid negative feedback by adrenalectomy. We demonstrate, using quantitative immunoelectron microscopy, that long-term adrenalectomy induces a progressive increase in the ratio of vasopressin to corticotropin releasing factor-41-immunoreactive sites in the dense-core vesicle compartment. The intravesicular concentration of vasopressin appeared to be the variable parameter while that of the corticotropin releasing factor-41 remained stable at all survival times after adrenalectomy. Moreover, observations for up to 5 weeks indicate that adrenalectomy results in a progressive increase in the mean volume of dense-core vesicles to about three times normal. These results suggest that the quantal size and the composition of dense-core vesicles are subject to long-term modulation. The capacity of corticotropin releasing factor-41 neurons to alter dense-core vesicles could enhance or diminish the efficacy of the hypothalamohypophyseal communication underlying physiological adaptation to stress, as well as pathological changes. 相似文献
1000.