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991.
Jeffrey H. Ware Angela J. Dibenedetto Randall N. Pittman 《Brain research bulletin》1995,37(3):275-281
The distribution of tissue plasminogen activator (tPA) messenger RNA in rat brain was studied using in situ hybridization with 35S UTP-labeled RNA probes derived from a fulllength tPA cDNA. Sense strand controls produced low, even backgrounds, with small elevations in the hippocampus. Full-length antisense probes produced strong signals over cerebral ventricular ependyma (including ependyma of the subcommissural organ), meninges, blood vessels, and Purkinje cell layer of the cerebellum, as well as strong signals over scattered cells throughout the brain. Some of these scattered labeled cells were large with lightly stained nuclei, while others were small with darkly stained nuclei. The large labeled cells, which were probably neurons, constituted 8% and 8% of cells in the brain stem and neocortex, respectively, and 100% of Purkinje cells. The small cells, which were present in all areas of the brain, constituted 3–11 % of cells in individual brain areas. 相似文献
992.
Hiroshi Shimada Masao Nanko Shoichi Fujii Hidenobu Masui Shinji Togo Hideyuki Ike Akira Nakano Shigeo Ohki 《Journal of Hepato-Biliary-Pancreatic Surgery》1995,2(2):116-121
Hepatic micrometastases of the parenchyma adjacent to a macroscopic lesion were detected in 17 of 31 resected liver metastases.
Fifty-nine micrometastatic lesions were detected in total; 26 lesions were situated in the portal vein (PV), 22 in the central
vein (CV), 5 in the bile duct (BD), and 6 in the sinusoid (SS). A histological study confirmed the direct invasion of the
macrometastatic cancer cells into the adjacent PV, CV, BD, and SS. According to the tumor doubling time, the mean diameter
of the macrometastases in 19 remnant livers was calculated to have been 0.57±0.87 cm at the time of the primary resection.
The calculated diameter of 3 of these 19 macrometastases was found to be less than 0.01 cm, the minimum implantable size,
indicating that the cancer recurrence in these specimens may have developed from macroscopic metastatic lesions as a satellite,
and not from the primary tumor. In 13 patients who received doses of 5250 mg or more of 5 fluorouracil (FU) via the hepatic
artery, the cumulative disease-free rate 2 years postoperatively was 100%; this value was 47.6% in 11 patients who received
less than 5250 mg of 5 FU via the hepatic artery, and 0% in 39 patients who received no chemotherapy (P<0.005). These results suggest that anatomical hepatic resection for satellite lesions, combined with prophylactic hepatic
arterial chemotherapy for micrometastases, decreases the recurrence rate of hepatic metastases in the remnant liver. 相似文献
993.
994.
应用抗增殖细胞核抗原和抑癌基因p53蛋白的单克隆抗体对37例放疗或化疗后的肺癌进行了检测,并与未经术前治疗的肺癌组织进行对照,部分组织进行了超微结构观察。结果发现:(1)放疗或化疗对肺癌组织细胞浆及胞核有不同程度的破坏。(2)放、化疗后组织(除分化型腺癌外)PCNA指数下降明显(P<0.01或P<0.05)。(3)放疗后肺癌组织p53表达率减低,但化疗后变化不明显。 相似文献
995.
维生素E对培养心肌细胞脂质过氧化损伤的保护 总被引:3,自引:0,他引:3
应用氢过氧化枯烯引发体外培养的乳鼠心肌细胞脂质过氧化损伤过程,观察了添加维生素E(200mg/L的α-生育酚)的影响。结果显示:维生素E能明显减轻细胞脂质过氧化物的蓄积、细胞内肌酸激酶漏出和DNA断裂,保护细胞膜流动性、肌球蛋白轻链肌酸激酶和头部ATP酶的活性;但对 ̄3H-TdR掺入的影响不显著。表明维生素E具有抵抗脂质过氧化所致心肌细胞损伤的作用。 相似文献
996.
Donald F. Orton M.D. Dennis F. Strauss M.D. Michael Hummel M.D. Dale Orton M.D. F.A.C.E.P. 《Emergency radiology》1998,5(3):173-175
The intraperitoneal mass most commonly encountered after blunt abdominal truama is a hematoma. However, one must also consider
unusual bulky tumors that can have imaging characteristics similar to those of hematoma. The most typical of these neoplasms
is lymphoma, but a desmoplastic small cell tumor also may be observed. The presentation and imaging findings of a desmoplastic
small tumor are described. 相似文献
997.
目的:研究进展期胃癌患者外周血T细胞免疫功能状态,手术对T细胞免疫功能的影响,以及对术后免疫治疗的指导。方法:采用间接免疫荧光染色流式细胞仪检测法,对43例进展期胃癌患者作手术前后外周血T细胞及亚群的测定,17例健康人作术前正常对照组。结果:与对照组相比,术前患者CD_3~+、CD_4~+细胞及CD_4~+/CD_8~+比值显著减少(P<0.01),而CD_8~+细胞无差异(P>0.05)。9例行非根治术者,手术前后T细胞及亚群无明显变化;而34例行根治术者,术后除CD_8~+细胞无变化外,CD_3~+、CD_4~+细胞及CD_4~+/CD_8~+比值均较术前有显著提高(P<0.01或P<0.05)。结论:术前进展期胃癌患者外周血T细胞免疫功能低下,行根治性切除术后得以改善。术后辅助免疫治疗或免疫化疗,以期提高生存率。 相似文献
998.
Myelodysplastic syndromes (MDS) have rarely been reported after treatment with nucleoside analogues, and mainly in patients who have also received alkylating agents. We report a patient who developed MDS (refractory anaemia with ring sideroblasts) after treatment with pentostatin (deoxycoformycin) alone. 相似文献
999.
JOHN H BOND 《Journal of gastroenterology and hepatology》1998,13(Z3):S252-S256
Abstract Colorectal cancer is the second most common cancer killer of Americans. Recently developed and tested methods of screening and surveillance can effectively diagnose and treat the disease in most patients before symptoms develop when the chance of cure is high. It is also possible to prevent colorectal cancer by detecting and resecting premalignant adenomatous polyps. Evidence-based guidelines recommend that the average-risk population greater than age 50 be screened with annual faecal occult blood tests plus periodic flexible sigmoidoscopy. This approach is feasible, efficacious, affordable and cost-effective in a high-risk country such as the US. Widespread compliance with these recommendations could reduce the mortality from this malignancy by more than 50%. 相似文献
1000.
用半固体双层琼脂培养法,将白血病细胞植入底层,正常CFU-GM植入上层,作白血病细胞与正常CFU-GM的共同培养。结果发现,底层琼脂中加入0.5×105/ml的白血病细胞后,上层琼脂中的CFU-GM从对照组的193.5下降至123.1/1×105个骨髓有核细胞(BMNC),加入底层的白血病细胞增加时,CFU-GM生成进行性受抑制,当植入的白血病细胞数达15×105/ml时,几乎无CFU-GM生成。此抑制作用亦见于白血病细胞的培养上清液中。量-效关系测定发现,正常CFU-GM培养体系中加入10%的白血病细胞培养上清液时,CFU-GM生成率从对照纪的112.2下降到88.6/1×105BMNC,以后抑制效应不再增加。以上结果揭示,白血病细胞对CFU-GM的抑制是经某种体液因子实现的。 相似文献