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91.
Organization of dopamine D1 and D2 receptors in human striatum: receptor autoradiographic studies in Huntington's disease and schizophrenia 总被引:3,自引:0,他引:3
The technique of quantitative autoradiography was used to examine the effects of Huntington's disease (HD) and schizophrenia on the organization of striatal dopamine (DA) D1 and D2 receptors. Whereas the striatum of HD cases showed a reduction in the density of D1 ([3H]SCH 23390) and D2 ([3H]spiroperidol) receptors, the patterning of D2 receptor loss did not match that of the D1 receptor loss. The HD loss of D1 D1 receptors (65%) is far greater than the loss of D2 receptors (28%). Whereas there was a dorsal-ventral gradient of effect on both receptor subtypes, the effects of HD on D2 receptors in the ventral putamen (PUT) and nucleus accumben septi (NAS) were minimal. Similarly, muscarinic M1 and M2 receptors demonstrate different patterns of alteration in HD. The M2 subtype, labeled with [3H]N-methylscopolamine (in the presence of excess pirenzepine to occlude M1 sites), was depleted far more than the M1 receptor subtype, labeled with [3H]pirenzepine. Although the effects of HD on [3H]mazindol labeling of DA terminals were more heterogeneous, there appeared to be a relative preservation of this afferent input to the striatum of the HD cases. In the schizophrenic cases, our autoradiographic studies confirm previous reports of an elevation of D2 receptor density in the striata of many schizophrenics. This increase was evident even though two of the three cases were known to have not been treated with neuroleptics, and the third case may also have been drug naive. However, the increase was far greater in the NAS (164%) and ventral PUT (173%) than more dorsally in the striatum (68%). The density of D1 receptors and DA terminals labeled with [3H]mazindol in the striatum of schizophrenics was not significantly different from that of control cases. Thus in both HD and schizophrenia, the ratio of D2/D1 receptors is altered in favor of the D2 population, particularly in the NAS. 相似文献
92.
The distribution of GABA-producing neurons in the brainstem auditory nuclei of the rat was investigated immunohistochemically by using an antibody to glutamic acid decarboxylase (GAD). In the cochlear nuclei, GAD immunoreactive neurons are present only in the superficial granular and molecular layers, whereas terminals are found in all subdivisions of the nuclei and are particularly dense surrounding large spherical cells and one type of stellate cell. In the superior olivary complex, GAD immunoreactive neurons are located in the lateral olivary nucleus and throughout the periolivary region. Immunoreactive terminals are distributed along dendrites of principal cells of the medial and lateral olivary nuclei and are clustered around somata of globular neurons of the nucleus of the trapezoid body. An extremely dense band of immunoreactive somata and terminals is present along the ventral edge of the olivary complex. The ventral, intermediate, and dorsal nuclei of the lateral lemniscus contain small fusiform GAD-immunoreactive neurons and a moderately dense plexus of immunoreactive terminals. The inferior colliculus contains a large population of GAD-immunoreactive perikarya and an extremely dense accumulation of immunoreactive terminals in the central, dorsomedial, and external nuclei. These observations indicate that GABA systems are involved in function at all levels of the brainstem auditory pathway. 相似文献
93.
颈椎侧块钢板在脊髓型颈椎病治疗中应用 总被引:2,自引:1,他引:1
目的 对15例脊髓型颈椎病患者行后入路椎管减压、椎板成型术的同时使用颈椎侧块钢板固定,探讨和分析该手术方法的优点和手术治疗效果。方法 从自2000年3月—2002年12月,对15例脊髓型颈椎病患者(术前颈椎MR显示有三个节段颈椎椎间盘水平病变并有黄韧带增厚突入椎管),行颈椎后入路双开门椎板成型术加双侧颈椎侧块钢板固定。按JOA评分法评定患者手术前后恢复情况。结果 本组患者男10例,女5例,随访5个月—1年2个月,平均9个月,术后2—7天(平均3.5天)可戴颈围坐起,颈围外固定时间12周,融合时间3—5个月,(平均为3.5个月),术后JOA评分明显提高,所有病人无术中血管、神经根损伤,无植骨不愈合,无内固定断裂。结论 行颈椎后入路双开门椎板成型术联合应用颈椎侧块钢板固定,从后方扩大椎管容积,对脊髓进行减压,辅助以侧块钢板对减压后的颈椎行即时的稳定的固定,增加后方所植髂骨的融合成功率,大大地减少颈椎术后后突畸形发生和术后卧床并发症的发生率。 相似文献
94.
95.
颈椎前路钢板在脊髓型颈椎病前路手术中的作用 总被引:10,自引:2,他引:8
目的 评价内固定在脊髓型颈椎病前路减压中的作用。方法 143例脊髓型颈椎病患者经前路减压后自体髂骨植骨,带锁钢板内固定。获得随访病例132例,随访时间平均20个月,观察术后神经功能恢复情况,植骨融合率,椎间高度及颈椎生理曲度恢复情况。结果 单节段与两节段病变者术后3月均获得骨性愈合,融合率为100%,16例3节段病变者融合体为81.3%,内固定并发症为5/132(3.8%)。术后椎间高度与生理曲度均获得满意重建。JOA记分平均改善率65.8%。结论 在脊髓型颈椎病前路减压手术中应用带锁钢板内固定可有效维持椎间高度和生理曲度,并有助于后路间接减压。 相似文献
96.
[目的]探讨伴有上肢局部水肿的颈椎病患者的发病机理和与手术颈椎减压的关系。[方法]总结分析4a来收治的10例伴有上肢局部水肿的颈椎病人,其中脊髓型颈椎病7例,神经根型颈椎病2例,后纵韧带骨化型1例,7例行前路椎体次全切减压植骨内固定,1例行前路椎体次全切+单间隙间盘摘除植骨内固定,2例行后路减压植骨内固定,术后观察患者水肿消退情况。[结果]10例病人上肢局部水肿不同程度消退,前路手术者较后路手术者消退快。[结论]颈椎病患者上肢水肿的发生与颈交感神经受激惹有关,通过前路或后路颈椎管减压,去除颈椎不稳、椎间盘突出、骨赘等交感神经受激惹因素,水肿可逐步消退。 相似文献
97.
Y. SUZUKI† T. NAKANO† T. OHNO† S. KATO Y. NIIBE S. MORITA & H. TSUJII 《International journal of gynecological cancer》2006,16(1):306-311
The presence of hypoxic cells is one of the major factors affecting resistance against radiation therapy. In the clinical setting, little information exists as to the relationship between intratumoral oxygen partial pressure (pO(2)) and outcome. This study involved 30 consecutive patients with cervical cancer, who were treated with a combination of external and high-dose rate intracavitary irradiation. The pO(2) was measured before radiation therapy and at 9 Gy, using a needle-type polarographic oxygen electrode. The mean intratumoral pO(2) before radiation therapy was 17.3 +/- 10.8 mm Hg. The 3-year local control rates of patients with pO(2)< or = 20 mm Hg and pO(2) > 20 mm Hg before radiation therapy were 52% and 100%, respectively, representing a significant difference (P= 0.035). At 9 Gy, mean intratumoral pO(2) was 23.6 +/- 9.1 mm Hg, a significant increase compared to the value before radiation therapy (P= 0.006). The 3-year local control rates of tumors with pO(2)< or = 20 mm Hg and pO(2) > 20 mm Hg at 9 Gy were 35% and 93%, respectively, representing a significant difference (P= 0.001). The significantly better local control for oxygenated tumors at 9 Gy as well as before radiation therapy indicated that the oxygen effect and reoxygenation by radiation played an important role in local control in radiation therapy for cervical cancer. 相似文献
98.
J. BYROM G. DOUCE† P.W. JONES‡ H. TUCKER J. MILLINSHIP K. DHAR & C.W.E. REDMAN 《International journal of gynecological cancer》2006,16(1):253-256
The reliability and applicability of colposcopically directed cervical punch biopsy was assessed in a sample of 170 paired punch and large loop excision of cervical transformation zone (LLETZ) specimens obtained from previously untreated women who had been selected for treatment on the basis of cytology and/or colposcopic findings and in whom the entire cervical transformation zone was visible. A single punch biopsy was taken immediately before the LLETZ, and all the specimens were reviewed by a single pathologist. Nine (5.3%) punch biopsies were inadequate. In terms of whether or not there was cervical intraepithelial neoplasia (CIN), the chance-corrected kappa analysis rated overall agreement as poor (kappa = 0.21, 95% confidence limits 0.02-0.39), whereas in terms of histologic grade, it was fair to moderate (kappa = 0.32, 95% confidence limits 0.23-0.42). Punch biopsy tended to underestimate the disease. The sensitivity and specificity of colposcopically directed punch biopsy for the detection of high-grade CIN was 74% and 91%, respectively, with positive- and negative predictive values of 97% and 48%, respectively. Two microinvasive and two intraepithelial glandular lesions were missed on punch biopsy. Punch biopsy should be avoided when high-grade disease is suspected. 相似文献
99.
G. GIORDANO T. D'ADDA L. GNETTI E. FROIO C. MERISIO† & M. MELPIGNANO† 《International journal of gynecological cancer》2006,16(4):1601-1607
In this study, we evaluated the presence of human papillomavirus (HPV) DNA in organs of the female upper genital tract, using nine hysterectomy and salpingo-oophorectomy specimens affected by HPV-positive invasive cervical carcinomas, to establish if cervical HPV infection can spread to upper tracts of the female genital system. HPV DNA was evaluated by polymerase chain reaction (PCR) in all cervical carcinomas as well as in all tracts of the genital system. Then, these data were compared with the results obtained from PCR study of five other hysterectomy and salpingo-oophorectomy specimens (control cases). The criteria used for selection of the control cases were informed consent of the patients for research at the time of surgery, absence of neoplasms, absence of any anatomic lesion caused by HPV in cervix, and external genitalia. All selected cases were squamous cervical carcinomas. PCR analysis revealed HPV DNA in all cases of cervical carcinoma. The HPV DNA was detected as weak positivity on PCR analysis in other organs of the genital system. However, the distribution of HPV DNA varied in the various cases and in the different tracts of the same hysterectomy and salpingo-oophorectomy specimen. We believe that the HPV DNA, detected as a weakly positive signal, in the upper genital tract of patients who have a cervical squamous carcinoma could be a reflection of a latent HPV infection, as well as a sign of the existence of micrometastases containing HPV DNA, which cannot be detected by conventional histologic techniques. 相似文献
100.
人心和山羊心脏上、下腔静脉肌袖大体解剖 总被引:2,自引:2,他引:0
目的:观测人和山羊上、下腔静脉肌袖结构特点,为治疗局灶性心房颤动积累解剖学资料。方法:采用大体解剖方法观测人心(20例)和羊心(40例)的上、下腔静脉及其表面的心肌纤维。结果:人心上腔静脉肌袖的长和宽分别为(1.91±0.39)cm、(2.41±0.26)cm,下腔静脉肌袖的长和宽分别为(1.32±0.32)cm,(3.06±0.52)cm;羊心上(前)腔静脉肌袖的长和宽分别为(1.41±1.00)cm、(1.05±0.26)cm,下(后)腔静脉肌袖的长和宽分别为(0.81±0.48)cm,(1.03±0.28)cm。人和羊心脏的上腔静脉肌袖出现率均为100%;下腔静脉肌袖的出现率分别为88.89%和98%。肌纤维多数来源于右心房前后壁,也有来自于左心房或左右心房的。结论:①上腔静脉肌袖是人和羊普遍存在的解剖结构,人的下腔静脉肌袖出现率明显低于羊,可能是上腔静脉肌袖引起局灶性心房颤动多于下腔静脉肌袖的解剖学基础。②上腔静脉肌袖是构成左右房的又一重要通路。 相似文献