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991.
The electrokinetic properties of artificial particles--microcapsules--were compared with those of the rat lymphocyte sub-populations, T and B cells, and similar results were obtained. The affinity of the microcapsules to the polyamine graft co-polymer, which was claimed to be capable of separating the cells efficiently, was measured and it revealed that not the magnitude of the surface negative charge and the kind of dissociable groups, but the balance of the anionic and cationic charges on the microcapsule surface played a key role in their adsorption to the co-polymer.  相似文献   
992.
In commercial powdered natural products for medicinal use containing various combined forms of hydroxyanthraquinone derivatives such as Sennae Folium, Cassiae Semen, Rhei Rhizoma and Aloe a considerable amount of stable free radicals (ca. 10(17)-10(18) spin/g) was found to be contained by use of electron spin resonance (ESR) spectral measurements. It was also found that the vibratory milling of such powders in a metallic vessel enhanced the ESR spectral intensities, demonstrating the occurrence of mechanoradical formation. Separate experiments also demonstrated that the vibratory milling of various kinds of powdered hydroxyanthraquinone derivatives mixed with calcium oxalate has produced the mechanoradicals effectively, but they decayed gradually on standing at room temperature. It was suggested, therefore, that the mechanoradicals formed in the above natural products are metal complexes of the corresponding semiquinone anion radicals induced by solid state one electron transfer mechanism from the active metal surface, part of which is further immobilized in polymeric fibers or the like in the plant tissues.  相似文献   
993.
994.
S Kondo  S Tanaka  T Tanaka  Y Yonemasu  T Hori 《Brain and nerve》1989,41(12):1185-1190
It is well known that hippocampus has an important role in the development of limbic seizures in the experimental model of epilepsy. Intrahippocampal microinjections of the ibotenic acid (IBO) resulted in various degree of hippocampal degenerations and influences of these lesion upon amygdaloid kindling rats. A stereotaxic operation was carried out and bipolar electrodes were placed unilaterally in amygdala and hippocampus. The IBO solutions were injected bilaterally into dorsal hippocampus (DH) in Group A, into ventral hippocampus (VH) in Group B and into DH and VH in Group C. Phosphate buffer solutions were injected in Group D as a control. All rats were subjected to amygdaloid kindling more than 8 days after the operation. Group A, Group B, Group C, and Group D (controls) required 10.3 +/- 2.6, 11.3 +/- 2.6, 17.4 +/- 4.4 and 8.7 +/- 2.3 stimulations for the Stage V seizures, respectively. The kindling rate in Group C increased compared with controls and this increase was statistically significant (P less than 0.01). A histopathological study revealed remarkable degenerative changes in DH of Group A, in VH of Group B and all over the hippocampus in Group C. The result suggested facilitatory interaction of the hippocampus upon amygdaloid kindling.  相似文献   
995.
996.
We report on four cases of endocervical adenocarcinoma associated with lobular endocervical glandular hyperplasia using histochemical and immunohistochemical analyses. The patients ranged in age from 59 to 67 years (mean 62 years). Chief complaints were watery vaginal discharge in two cases, genital bleeding in one and no subjective symptoms in one. Cytological examinations of the cervical smears revealed adenocarcinoma cells and benign-looking glandular cells with intracytoplasmic golden-yellow mucin in all cases. Radical hysterectomy was performed in three patients, and simple total hysterectomy was performed in one. From surgical specimens, three tumors were diagnosed as mucinous adenocarcinoma and one was adenocarcinoma in situ. All adenocarcinomas were located proximally on the cervix, and did not involve the transformation zone. Adjacent to carcinoma tissues in the cervix, lobular endocervical glandular hyperplasia was detected. The cells of lobular endocervical glandular hyperplasia were dominantly positive with neutral mucin, and immunohistochemistry revealed that these cells had prominent pyloric gland mucin (HIK1083). Focal immunopositivity for pyloric mucin was also observed in three adenocarcinomas. Either CEA or p53 were immunopositive in all adenocarcinomas and negative in the tissues of lobular endocervical glandular hyperplasia. Histopathological features of the present cases suggest that some endocervical adenocarcinomas may originate from lobular endocervical glandular hyperplasia.  相似文献   
997.
The human papillomavirus (HPV) is basically always detected in squamous cell carcinoma of the cervix and its precursors; a high incidence of HPV also has been reported in adenocarcinoma and adenocarcinoma in situ of the uterine cervix. Lobular endocervical glandular hyperplasia (LEGH) was first described by Nucci in 1999. It is difficult to differentiate minimal deviation adenocarcinoma (MDA) from LEGH preoperatively or postoperatively by clinical and pathologic features. The relationships between HPV and MDA or LEGH have not been studied well because of the rare incidence of the two diseases. To our knowledge, the HPV status in LEGH has not been reported. This study was designed to investigate HPV infection in MDA and LEGH, using the polymerase chain reaction (PCR) technique. Tumor tissue lesions were microdissected and the detection of HPV and its typing were analyzed by PCR-based assay. As the control, HPV DNA was detected in all cases of squamous cell carcinoma and three of five cases of adenocarcinoma. However, no HPV DNA was detected in any of the 10 cases of LEGH or in the 3 cases of MDA. These results suggest that MDA and LEGH are probably not related to HPV infection.  相似文献   
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