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41.
Ivan Tkác Pierre-Gilles Henry Peter Andersen C Dirk Keene Walter C Low Rolf Gruetter 《Magnetic resonance in medicine》2004,52(3):478-484
An efficient shim system and an optimized localization sequence were used to measure in vivo 1H NMR spectra from cerebral cortex, hippocampus, striatum, and cerebellum of C57BL/6 mice at 9.4 T. The combination of automatic first- and second-order shimming (FASTMAP) with strong custom-designed second-order shim coils (shim strength up to 0.04 mT/cm2) was crucial to achieve high spectral resolution (water line width of 11-14 Hz). Requirements for second-order shim strengths to compensate field inhomogeneities in the mouse brain at 9.4 T were assessed. The achieved spectral quality (resolution, S/N, water suppression, localization performance) allowed reliable quantification of 16 brain metabolites (LCModel analysis) from 5-10-microL brain volumes. Significant regional differences (up to 2-fold, P < 0.05) were found for all quantified metabolites but Asp, Glc, and Gln. In contrast, 1H NMR spectra measured from the striatum of C57BL/6, CBA, and CBA/BL6 mice revealed only small (<13%, P < 0.05) interstrain differences in Gln, Glu, Ins, Lac, NAAG, and PE. It is concluded that 1H NMR spectroscopy at 9.4 T can provide precise biochemical information from distinct regions of the mouse brain noninvasively that can be used for monitoring of disease progression and treatment as well as phenotyping in transgenic mice models. 相似文献
42.
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
43.
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
44.
Abstract. A total of 81 rat kidney grafts, flushed out and cold stored in either Sacks' or University of Wisconsin (UW) solution, were transplanted into hemodiluted (Hct = 30%± 4%) or untreated (Hct = 43%± 3%) recipients. The cold ischemia times (CIT) used were 24 and 36 h. One week after transplantation, the surviving recipients ( n = 67) were contralaterally nephrectomized. The experiment was terminated after a total period of 4 weeks, and the percentage of surviving animals was determined for each treatment. Data was pooled and the results show that grafts cold stored in UW solution were viable to a significantly greater extent and after longer CIT than grafts cold stored in Sacks' solution (47% vs 23%; P < 0. 05). Recipient hemodilution did not improve graft viability (39% vs 32%; NS). Kidneys cold stored for 24 h were viable to a greater extent than kidneys with a CIT of 36 h (50% vs 15%; P < 0. 01). 相似文献
45.
46.
Akitomo Shimoji M.D. Shoichi Katsuragi M.D. Taihei Miyakawa M.D. Ryoichi Hira M.D. Kenjiro Watanabe M.D. Kohei Miyakawa M.D. Takateru Ishitsu M.D. Teruhisa Miike M.D. 《Psychiatry and clinical neurosciences》1987,41(1):47-55
Abstract: We report here two cases in a family with pleomorphic clinical features which include mitochondrial myopathy, encephalopathy, stroke-like episodes, episodic disturbances of consciousness and other multisystemic abnormalities. The other signs observed in multisystemic abnormalities were ophthalmoplegia, short stature, diabetes mellitus, diabetes insipidus, renal dysfunction, optic atrophy, retinal degeneration, impairment of hearing and mental retardation or deterioration. A symptomatological variation was observed in cases in the same family. It is suggested that these widely varying symptoms may be expressions caused by a common biochemical defect which involves different tissuesin different individuals in the family. The syndromes observed in the present cases were compared with other possibly-related mitochondrial encephalomyopathies. 相似文献
47.
Uta Lichter-Konecki Christian Benninger Werner E. Brandeis Peter Matthis Dieter Scheffner 《Pediatric hematology and oncology》1987,4(1):77-85
Thirteen children with acute lymphoblastic leukemia (ALL) were investigated before and during cytotoxic therapy. EEG findings were correlated with the clinical course and the therapy protocol and compared with normal data obtained from 295 healthy children. Frequency analysis of the background activity of the EEG revealed an initial slowing of the background activity prior to therapy and further slowing each time a combination of vincristine (VCR), daunorubicine (DAU) or adriblastine (ADR), prednisone (FRED), and L-asparaginase (L-ASP) was administered. The slowing of the background activity correlated only with the administration of these drugs. DAU, ADR, and FRED are not known to influence the EEG; therefore, VCR and L-ASP remain the primary candidates responsible for the central nervous system alteration. 相似文献
48.
While two prophylactic HPV vaccines have been proven notably efficacious in clinical trials, the effectiveness of these vaccines at the population level remains to be evaluated. To lay the foundation for understanding the strengths and limitations of different endpoints for future effectiveness research, we present a comprehensive review of HPV-related clinical outcomes, including: (i) HPV type-specific positivity and persistence, (ii) Pap diagnoses (ASC-US, LSIL, and HSIL), (iii) histologic cervical cancer precursor lesions (i.e., CIN1, CIN2, and CIN3), (iv) invasive cervical cancer (ICC), (v) anogenital warts, (vi) recurrent respiratory papillomatosis (RRP), and (vii) other HPV-associated cancers (vulvar, vaginal, anal, penile, and oropharyngeal). While research on the vaccines’ effects on these HPV clinical outcomes in the general population is presently limited, numerous large trials will soon be completed, making a priori discussion of these potential outcomes especially urgent. Furthermore, population level systems to track HPV-associated clinical outcomes may need to be developed for HPV vaccine effectiveness evaluation. 相似文献
49.
50.
眼轴线后部眶容积增大与眼球内陷比值的测定研究 总被引:1,自引:0,他引:1
目的:通过测量眼眶爆裂性骨折伴有眼眶扩大患者的后部眼眶容积、观察眼球内陷出现的时间及程度,研究后部眶容积扩大与眼球内陷的关系比值,为病情预测和眶内填充手术提供比较精确的参考数据。方法:将96例患者按发病时间分为早期病例组(60例、受伤时间1周以内)和晚期病例组(36例、受伤时间3个月以上),早期组除进行后部眼眶容积测量外,分别于1周、2周、3周测定眼球突出度(相差>1mm为阳性),记录眼球内陷出现时间,用卡方检验进行统计学分析;晚期组测量后部眶容积增大值和眼球内陷量,对其相关性采用Pearson统计方法进行统计学分析,并得出回归方程及相关系数。结果:早期组60例患者中,(58.33%)例患者在1周内出现眼球内陷,4(880%)例在2周内出现内陷,3周时有5(388.33%)例呈现出内陷;2周时出现眼球内陷的例数与1周时有显著性差异(χ2=62.484,P<0.001),2周时出现眼球内陷例数与3周时无差异(χ2=1.563,P>0.05),1周时出现眼球内陷例数与3周时有显著差异(χ2=76.885,P<0.001),后部眶容积增大与眼球内陷的比值约为1.0,两者之间呈正相关(r=0.994,P<0.001),即后部眶容积每增加1ml,产生1.0mm的眼球内陷。结论:眼球内陷通常于伤后2周~3周出现,3个月时趋向稳定;后部眶容积增大与眼球内陷产生比值为1.0,呈正相关;后部眶容积扩大与眼球内陷比值可预测发生眼球内陷的可能性和程度,为手术矫正眼球内陷提供可靠、精确的参考,具有十分重要的临床指导意义。 相似文献