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41.
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
42.
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
43.
44.
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
45.
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
46.
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
47.
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
48.
胸腺肽增强狂犬病疫苗免疫效果的研究 总被引:4,自引:0,他引:4
目的 探索胸腺肽作为人用纯化Vero -细胞狂犬病疫苗佐剂的可能性。 方法 分为单针和多针狂犬疫苗免疫方案。单针免疫是用狂犬疫苗 1支加胸腺肽 1针免疫 ;多针免疫按常规五针免疫程序 (即 0、3、7、14、2 8d各注射1针 ) ,加胸腺肽组按三针免疫程序 (即 0、7、2 8d各注射 1针 ) ,实验小白鼠每只均以狂犬病疫苗 0 .2ml与胸腺肽混合后肌肉注射。 结果 单针免疫加入胸腺肽 ( 2mg/只 )后抗体效价高且抗体产生时间早 ,抗体水平显著高于疫苗组 (P <0 .0 1)。而且加入胸腺肽 ( 6mg/只 )后免疫三针可达到五针常规疫苗免疫效果。 结论 胸腺肽作为人用纯化Vero -细胞狂犬病疫苗的佐剂可减少免疫次数。 相似文献
49.
Kathleen A. Ward Sinead A. McKernan Natalina N. Durnien Wallace W. Dinsmore 《Journal of the European Academy of Dermatology and Venereology》1995,4(2):160-165
Objective Detection of HPV DNA in oral and genital lesions of a heterosexual male. 4 months after oral and vaginal intercourse with a woman with vulvar warts. Passible modes of acquisition of oral HPV infection in the male sexual partner are discussed. Setting Genitourinary Medicine clinic. Methods Polymerase chain reaction amplification of genomic DNA from oral and genital lesions. HPV DNA typing by dot blot hybridization. Results HPV DNA types 6 and 11 were identified in a polypoid tongue lesion and in a penile wart from the male sexual partner. Conclusions The acquisition of oral HPV infection in the male sexual partner may have resulted from genital-oral HPV transfer, either by direct contact with vulvar warts or by digital self-inoculation. 相似文献
50.
Objective To investigate the correlation between human epidermal stem cell (hESCs) and hypertrophic scar or keloid. Methods Improved collagen Ⅳ-coated adhesion methods was used to isolate and culture the epidermal stem cells after neutral protease selectively digested the dermo-epidermal junctions. After the cells were cultured and expanded in vitro, and passage 3 hESCs were induced by different concentrations of TGF-β1 (0.1, 5.0, and 10.0 ng/ml). Morphological fea-tures and identification of these cells were meseasured by HE, Masson, immunohistochemical staining on the days 3 and 7, respectively. Results After induced by TGF-β1 for 3 and 7 days, the morpholo-gy of the epidermal stem cell (hESCs) was changed into fusiform shape, similar to fibroblasts. 70 % ofthe cell which was induced by TGF-β1 were blue stained in the cytoplasm by Masson stain, which is the distinctive method for collagen, suggesting collagen appeared or increased in the cells. The collagen concentrations in supernatants of hESCs were 0.4150±0.0014, 0.3380±0. 0020, and 0.3870±0.0020, much higher than that in control group (0.0780±0.0025) and normal skin fibro-blast group (0.15004±0.0051) (P<0.05). Immunohistochemical staining revealed that positive rates of these cells for anti-vimentin staining were more than (95.00±1.20)% in experiments and (5.70±0.20)% in control group. Conclusion The differentiantion of hESCs induced by TGF-β1 into fibro-blasts indicates that hESCs may play a role in the pathogenesis of hypetrophic scar and keloid. 相似文献