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61.
Evidence for the presence of substance P-like immunoreactivity in the human cerebellum 总被引:1,自引:0,他引:1
M. Del Fiacco M. T. Perra M. Quartu M. D. Rosa G. Zucca M. C. Levanti 《Brain research》1988,446(1):173-177
Preliminary results on the localization of substance P-like immunoreactivity in the human cerebellum are presented. Cerebella from newborn and adult subjects were examined. While only sporadic positive fibres were detected in the adult tissue, the immunoreactive material appeared more abundant in the cerebella from newborn subjects. Varicose and non-varicose fibres and dot-like nerve terminals were present with different density in various regions. The paucity of immunoreactive perikarya suggests that most of the cerebellar substance P-like immunoreactive material has an extrinsic origin. 相似文献
62.
Peter Van Gelder Sergey Lebedev Wai Hon Tsui 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,116(2):201-215
Smooth pursuit typically includes corrective catch-up saccades, but may also include such intrusive saccades away from the
target as anticipatory or large overshooting saccades. We sought to differentiate catch-up from anticipatory and overshooting
saccades by their peak velocities, to see whether the higher velocities of visually rather than nonvisually guided saccades
in saccadic tasks may be found also in saccades in pursuit. In experiment 1, 12 subjects showed catch-up, anticipatory, and
overshooting saccades to comprise 70.4% of all saccades in pursuit of periodic, 30°/s constant-velocity targets. Catch-up
saccades were faster than the others. Saccadic tasks were run as well, on 19 subjects, including the 12 whose pursuit data
were analyzed, with target-onset, target-remaining (saccade to the remaining target when the other three extinguish), and
antisaccade tasks. For 17 of the 19 subjects, antisaccade velocities were lower than for either target-onset or target-remaining
tasks. Velocities for the target-remaining task were near those for target onset, indicating that target presence, not its
onset, defines visually guided saccades. Error and reaction-time data suggest greater cognitive difficulty for target remaining
than for target onset, so that the cognitive difficulty of typical nonvisually guided saccade tasks is not sufficient to produce
their lowered velocity. To produce reliably, in each subject, catch-up and anticipatory saccades with comparable amplitude
distributions, nine new subjects were asked in experiment 2 to make intentional catch-up and anticipatory saccades in pursuit,
and were presented with embedded target jumps to elicit catch-up saccades, all with periodic target trajectories of 15°/s
and 30°/s. Velocities of intentional anticipatory saccades were lower than velocities of intentional catch-up saccades, while
velocities of intentional and embedded catch-up saccades were similar. Target-onset and remembered-target saccadic tasks were
run, showing the expected higher velocity for the target-onset task in each subject. Both experiments demonstrate higher peak
velocities for catch-up saccades than for anticipatory saccades, suggesting that cortical structures preferentially involved
in nonvisually guided saccades may initiate the anticipatory and overshooting saccades in pursuit.
Received: 1 December 1995 / Accepted: 25 February 1997 相似文献
63.
64.
Symptom Clusters in Patients With High-Grade Glioma 总被引:2,自引:0,他引:2
65.
短发夹状RNA对PC-3M细胞端粒酶逆转录酶基因表达和端粒酶活性的影响 总被引:3,自引:0,他引:3
目的:研究短发夹状RNA(shRNA)对PC 3M细胞中端粒酶逆转录酶(hTRT)基因表达及端粒酶活 性的影响。方法:构建针对hTRT基因的shRNA表达质粒psilencer TRT,在质脂体介导下转染人前列腺癌PC 3M细胞,应用RT PCR及免疫组织化学检测hTRTmRNA及蛋白表达水平,应用SYBR Green染色法检测端粒 酶活性的变化。结果:重组体psilencer TRT转染细胞24h和48h后显著下调hTRTmRNA及蛋白水平,作用 48h后,其抑制率分别为85.39%和79.17%,较空白对照组差异有统计学意义(P<0.01)。同时,随着时间的延 长,端粒酶活性亦有明显下降(P<0.01)。结论:利用短发夹状RNA干扰技术能有效抑制靶基因的表达,为前 列腺癌的基因治疗提供新思路。 相似文献
66.
外源性p21WAF1/CIP1基因转染对人胶质瘤细胞生长和细胞周期的影响 总被引:2,自引:0,他引:2
目的:探讨外源性p21^WAF1/CIP1基因对胶质瘤细胞生长和细胞周期的影响.方法:采用脂质体介导法将p21^WAF1/CIP1基因质粒转导人人胶质瘤细胞系SHG44细胞,然后用电镜、流式细胞仪等技术对细胞形态、生长及细胞周期进行观察。结果:酶切电泳和斑点杂交显示p21^WAF1/CIP1基因成功的转染至SHG44细胞。转染p21^WAF1/CIP1基因的细胞光镜及电镜下可见凋亡产生;生长速度明显慢于亲代细胞,其倍增时间约是对照细胞的二倍;细胞周期发生明显改变,G1期明显增多,S期明显减少.结论:外源性p21^WAF1/CIP1基因对SHG44细胞的生长和细胞周期有明显的抑制作用,并可诱导细胞凋亡产生。 相似文献
67.
Decreased expression of DMPK: correlation with CTG repeat expansion and fibre type composition in myotonic dystrophy type 1 总被引:2,自引:0,他引:2
S. Salvatori M. Fanin C. P. Trevisan S. Furlan S. Reddy J. I. Nagy C. Angelini 《Neurological sciences》2005,26(4):235-242
Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine
(CTG)n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion
and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting.
We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying
different (CTG)n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did
not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect
DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre. 相似文献
68.
Md. Kabirul Islam 《Indian journal of pediatrics》2002,69(10):819-820
An interesting case of a child with a tail is reported. The child had a tail like structure in the back since birth, increasing
with age. It was 20 cm. long, the longest tail so far described in the English literature. There was no functional complain.
The result was excellent after excision as the problem was only cosmetic. 相似文献
69.
The thymus in seronegative myasthenia gravis patients 总被引:1,自引:0,他引:1
Summary In 5–10% of all patients with typical generalised myasthenia gravis (MG), serum antibody to the acetylcholine receptor (AChR) is undetectable. To determine whether these represent a distinct subgroup, we have compared the thymuses of 14 seronegatives, 70 seropositives and 12 non-myasthenic controls. By quantitative immunohistology on coded sections, the 7 seronegative samples were clearly distinguishable from the controls by the pronounced lymph node-type T-cell areas in the medulla. While these closely resembled those in the seropositive cases, germinal centres were significantly sparser, and total in vitro IgG production was disproportionately low (per B cell) in the 12 cases tested. Furthermore, specific anti-AChR production was never detected in any of these cultures. The data support the view that the medullary T-cell areas are the most consistent abnormalitiy in the MG thymus (though it may not be primary), and they strongly imply that seronegative and seropositive MG are distinct entities. 相似文献
70.
Demonstration of human papillomavirus types 6 and 11 in juvenile laryngeal papillomatosis by in-situ DNA hybridization 总被引:3,自引:0,他引:3
A study is reported in which an in situ hybridization technique for the demonstration of human papillomavirus (HPV) employing a biotin--streptavidin polyalkaline phosphatase complex has been successfully applied to formalin-fixed paraffin-processed tissue obtained from ten patients with juvenile laryngeal papillomatosis. In all cases, positive results were obtained for either HPV type 6 or 11. Normal vocal cord epithelium was negative. 相似文献