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91.
还原型谷胱甘肽和L-NAME对体外培养的脊髓运动神经元的影响 总被引:1,自引:0,他引:1
目的 :探讨还原型谷胱甘肽 (GSH)和L NAME对体外培养的脊髓运动神经元的保护作用。方法 :不同浓度的GSH和L NAME作用于脊髓运动神经元 ,3d后计算存活率。并测量存活率高的两组和对照组的免疫细胞化学标本的神经元形态学指标。结果 :GSH 10mmol·L-1和L NAME 1× 10 -3 mol·L-1组存活率最高。两实验组轴突长度、树突总长度、树突分叉点数目和胞体面积高于对照组。结论 :抗氧化剂和NOS抑制剂可以提高脊髓运动神经元的存活率 ,促进神经元生长 相似文献
92.
W. B. Quay 《Journal of neural transmission (Vienna, Austria : 1996)》1981,52(1-2):107-115
Summary Quantitative aspects of the microanatomy of the pineal gland and other neuroendocrine and circumventricular structures were studied in a small, reproductively suppressed, female Naked Mole-rat from central Kenya, Africa. The atrophic pineal is the smallest in absolute size (0.002135 mm3) of any so far described in a species of rodent, and in size relative to body weight is second only to that of another tropical species. The subcommissural organ and posterior collicular recess are also relatively small and less well differentiated than those in most other examined rodent species. In contrast, the subfornical organ, OVLT and median eminence are large and well vascularized. It is concluded that the pineal in this species follows the previously described trend among rodents of relatively smaller size in species whose centers of distribution are in lower latitudes. Although the pineal is atrophic, the Naked Mole-rat still exhibits 24-hour and seasonally timed patterns of behavior and seasonal reproduction. However, in this species these events are probably cued by moisture, temperature and social factors rather than by photic information. 相似文献
93.
Comparison of characteristics of esophageal squamous cell carcinoma associated with head and neck cancer and those with gastric cancer 总被引:3,自引:0,他引:3
H Kuwano M Morita S Tsutsui Y Kido M Mori K Sugimachi 《Journal of surgical oncology》1991,46(2):107-109
In ongoing reviews of 339 patients with surgically treated primary squamous cell carcinoma, there were 19 (5.6%) with concurrent gastric cancer and 11 (3.2%) with head and neck cancer. The incidences of intra-esophageal multiple occurrence of esophageal cancer are 27.3% and 26.3% in those with associated head and neck cancer and gastric cancer, respectively, and higher than 7.1% in those without such a concurrent cancer. There was no difference in the clinicopathological characteristics of those with concurrent head and neck and gastric cancers, except for the higher incidence of metachronous occurrence in the former. These findings suggest that, in cases of esophageal cancer associated with concurrent head and neck cancer and gastric cancer, intraesophageal multiplicity of the esophageal carcinoma is frequent and that preoperative serial evaluations is most important to design treatment and estimate the prognosis. 相似文献
94.
95.
While an exacerbation in allergic symptoms corresponding to seasons has long been reported, few studies have investigated the association between the season of birth and allergic disorders. The aim of this study was to investigate whether the climatologic data before and after birth affected the incidence of atopic dermatitis (AD) and the results of allergy-related blood tests in early infancy. From February 1995 to January 2000, 2136 infants were tested for AD and followed for 12 months. AD patients were tested by using allergy-related blood tests. Data were compared according to the month of birth and the climatologic data using a computed statistical software package. Six hundred and thirty infants had AD before 12 months old, and significant differences were found according to the season of birth (p < 0.0001). Infants born in spring showed the lowest (22.3%) incidence, while those born in autumn showed the highest (34.6%). In 369 patients, total serum IgE levels, and serum specific IgE levels with egg white at 3 months old were also different according to the season of birth. All of these levels were lower in patients born in spring and summer, and higher in patients born in autumn and winter. Furthermore, the cumulative sunshine amount during the 3 months before and after birth was inversely correlated, while the average temperature over the 3 months before birth was positively correlated to the incidence of AD according to the month of birth. The climatologic data around birth may play an important role in whether an infant develops allergies. 相似文献
96.
The rearrangement of terminations from the bed nucleus of stria terminalis (BST) was examined in the medial amygdaloid nucleus (MAN) at 2 months following the lesion of the accessory olfactory bulb (AOB) using an electron microscopy and degeneration study. At 2 days following a BST lesion, the number of degenerating synapses was 0.7 ± 0.1 (mean±S.E.M.) per unit area (2500 μm2 in the molecular layer, and 3/0 ± 0.3 in the cellular part. At 2 months after an AOB lesion, the degenerating synapses from the AOB had completely disappeared from the MAN. The BST was then lesioned at 2 months after the AOB lesion and, 2 days following this BST lesion, the degenerating synapses were counted in MAN. The numbers observed were 3.3 ± 0.6 per unit area in the molecular layer and 4.5 ± 0.4 in the cellular part. Therefore, the number of these degenerating synapses increased significantly within the molecular layer, though, in the cellular part the number of synapses was not significantly elevated over control. No differences in postsynaptic profiles (ratio of synapses on dendritic spine to dendritic shaft) were observed after the AOB lesion. These results indicate that the BST fibers formed new synapses in the molecular layer following the denervation of AOB fibers. The possibility of new synapse formation by other afferent fibers in addition to the AOB fibers is discussed as is the relationship between lesion induced synaptic reorganization and functional recovery after injury. 相似文献
97.
牙根发育不良疾病的研究进展 总被引:2,自引:0,他引:2
牙根发育不良疾病是牙齿根部生理性发育出现障碍的疾病。其发病率为1%~10%,乳、恒牙列均可发生,其结果可导致牙根缺如或短根,严重者可造成牙齿过早脱落。国外学者将该疾病统称为短根异常疾病。其发病因素有遗传性疾病、全身性疾病、外源性因素和医源性因素等。 相似文献
98.
99.
100.
G Titeca†§ F Poot†§ D Cassart‡ B Defays† D Pirard†§ M Comas† P Vereecken†¶†† V Verschaevec P Simon† M Heenen† 《Journal of the European Academy of Dermatology and Venereology》2007,21(6):771-776
BACKGROUND: Breast cancer is the most common cancer in women and therefore represents a major problem in public health. Data from patients' self-report questionnaires provide valuable information about the side-effects that patients may view as having a significantly detrimental impact on their quality of life (QOL) and yet are not always recognized as important by healthcare professionals. Cosmetology is a specific care for patients and there is actually no scientific evidence regarding effects on QOL for women with breast cancer. OBJECTIVE: The purpose of this study is to assess the impact of cosmetic care on QOL in breast cancer patients during chemotherapy and radiotherapy. METHODS: We developed a prospective, multicentre, randomized, controlled study including 27 patients. All the patients had to fill in a French-validated dermatologic specific quality-of-life questionnaire to compare the QOL of the two groups, the cosmetic group and the control group, at three different times of the adjuvant treatment. RESULTS: The results show a statistically significant difference between the cosmetic group and the control group in two areas of QOL: mood state and self-perception of the disease. CONCLUSION: This study emphasizes the interest of cosmetic care in breast cancer patients. However, further larger trials are needed to confirm this study. 相似文献