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11.
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Brain tissues from 6 patients with concentric sclerosis (Baló) were examined by in situ hybridization, immunocytochemistry, morphometry, and histological methods. The patients were 24 to 48 years old and had progressive cerebral symptoms and signs that lasted 15 to 100 days. Large demyelinative lesions, most frequent in the frontal white matter, contained alternating bands of demyelinated and partly myelinated white matter that were arranged in concentric or mosaic patterns. In the areas of demyelination, axons were relatively well preserved and there were perivascular inflammatory infiltrates. In 2 specimens, lesions contained regions with the characteristic appearance of actively demyelinating multiple sclerosis plaques. Oligodendroglial densities were highest in normal-appearing white matter, lower in partially myelinated areas, and lowest in demyelinated areas, which also contained many hypertrophic astrocytes closely associated with oligodendroglia. Messenger RNA levels for myelin-related proteins followed the same pattern; they were lowest in demyelinated areas, higher in partially myelinated areas, and highest in normal-appearing white matter beyond lesion margins. Our findings suggest that concentric sclerosis is a variant of multiple sclerosis, that oligodendroglial loss is important in the pathogenesis of demyelination, and that partially myelinated areas probably represent stages of ongoing myelin breakdown rather than remyelination of previously demyelinated areas.  相似文献   
13.
Pyogenic granuloma is one of the diseases sometimes seen in otorhinolaryngology clinics. The clinical features of this disease are understood to be that the lesion is located in the oral cavity in the majority of cases that its causative agent is usually discovered and that it most likely grows as a malignant tumor. However, the entity of pathological diagnosis has not been established. Thirty-one cases of oral pyogenic granuloma, including 16 males and 15 females, are reported in this paper. The granuloma was located most frequently at the tongue, followed, in order, by the gingiva, buccal mucosa, hard palate, lip and oral floor. The period between the patient's first visit to our clinic and the onset of his/her complaint was variable. It was relatively shorter in those cases with the lesion at the gingiva or tongue as compared to other locations. The size of the lesion was smaller than 10 x 10 mm. We classified the pathological features into three patterns; granuloma type, hemangioma type, and intermediate type. Many cases of lesions located at the back of the tongue, buccal mucosa, or hard palate were of the hemangioma type, while many cases of lesions located at the top of the tongue, gingiva, or oral floor were of the granuloma type. We have the impression that pyogenic granuloma could be one of the purulent changes associated with benign oral tumors.  相似文献   
14.
This study examines the possible beneficial effect of Re-LPS (F515) antiserum on experimental multiple system organ failure (MSOF) in rabbits. The results showed that the plasma LPS level was significantly decreased, and it took a shorter period to clear up LPS in experimental than in control rabbits after receiving Re-LPS antiserum. Pretreatment with antiserum can markedly improve the function of the liver, lungs, kidneys, blood and gastrointestinal tract. The MSOF incidence in the group of rabbits receiving immune sera was only 11.2% and the survival rate was raised by about 40.0%. The results suggest that early passive immunotherapy may neutralize gut-derived endotoxin, inhibit endotoxin-induced mediators release and prevent development of severe complications due to sepsis. It is therefore postulated that LPS core antiserum may provide a prophylactic effect on the development of experimental MSOF.
  相似文献   
15.
The effect of (+/-)-, (+)- and (-)-gossypol on testicular lactate dehydrogenase-X (LDH-X) was studied in vitro and in vivo. It was found that racemic gossypol and the two optical enantiomers had similar inhibitory effects on rat testicular LDH-X in vitro. However, neither racemic gossypol nor the enantiomers exhibited an inhibitory effect on testicular LDH-X in vivo. It is concluded that inhibition of testicular LDH-X is not likely to be the mechanism of the antifertility action of gossypol. The inhibition of testicular LDH-X in vitro by all three preparations of gossypol is probably non-specific.  相似文献   
16.
Sixty specimens of breast cancer were assayed with ER-monoclonal antibody by immunocytochemical staining. Twenty-nine (48.33%) were nuclear estrogen receptor positive (ERn+). The number of ERn+ cancer cells decreased in the following sequence: mucinous carcinoma, invasive lobular carcinoma, invasive ductal carcinoma, and papillary adenocarcinoma. Two apocrine carcinomas were ERn-. ERn+ rate was higher in patients over 60 years of age (P less than 0.05). The amount of ERn+ cells was much greater in cancer cells than in the surrounding benign epithelial cells. This phenomenon may indicate that malignant cells are more hormone-dependent than benign cells. The results of immunocytochemical staining and steroid binding assay were compared. By immunocytochemical staining, twenty-four of fifty-seven cases (42.11%) were ERn+ and ERc+. Sixteen cases (28.07%) were ERn- and ERc-. This study showed that in a number of breast cancers ERs were positive in both cytoplasms and nuclei and the concordant rate was 70.18%. In the remaining cases 13 (22.81%), ERs were positive in the cytoplasm, and in 4 cases (7.02%) positive in nuclei only. Additionally, fifty-two out of 60 cases were assayed by 3H-estradiol and 3H-R5020 by means of steroid binding assay. Twenty-seven cases of them (51.92%) showed ERc+ and PRc+, and seventeen cases (32.69%) were ERc- and PRc-. Their correspondent rate was 84.61%.  相似文献   
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18.
应用免疫细胞化学(ICC)和放射免疫分析(RIA)方法观察了大鼠4、25Gy~(60)Coγ射线照射后24,48和,72h空肠亮脑啡肽(L-ENK)样免疫反应性神经的分布和L-ENK含量的变化。结果:4Gy照射后24h以及25Gy照射后24,48和72h光镜下见空肠L-ENK样免疫反应性神经的分布密度稍有增加,4Gy照射后24h以及25Gy照射后24,48和72h空肠L-ENK含量分别为29.81±0.84pg/mg,34.96±4.38pg/mg,40.71±3.62pg/mg和38.93±2.31pg/mg,与正常对照组(18.26±1.95pg/mg)相比明显升高(P<9.01)。  相似文献   
19.
A case of a 20 year old Japanese woman who developed thyroid cancer exhibiting unusual cribriform structures while being followed up for familial adenomatous polyposis/Gardner's syndrome is reported. The patient presented with osteomas, pigmented retinal lesions, and adenomas of the duodenum and the papilla of Vater, in addition to numerous adenomatous polyps in the colorectum. On ultrasonography, the thyroid cancer was localised to the right lobe and was identified as an irregular, internal echo tumour with a peripheral hypoechoic zone, measuring 1.8 cm in diameter. Histological examination of the resected tumour showed a concomitance of papillary proliferation and cribriform structures with follicles of varying sizes. These features can be distinguished from sporadic thyroid cancer.  相似文献   
20.
A case of postoperative prosthetic hip joint infection due to Campylobacter fetus subsp. fetus is described. Difficulties in isolation and antimicrobial susceptibility testing of this organism are discussed.  相似文献   
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