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131.
In the buffalo the sympathetic ganglionic neurons were multipolar and contained finely granular or vesicular Nissl material and eccentric nuclei with more than one nucleolus. They measured (mean values) 23.62 X 14.30 mum in the cranial cervical ganglion, 22.51 X 13.58 mum in the vertebral ganglion, 25.25 X 15.75 mum in the cervicothoracic ganglion and 22.84 X 14.27 mum in the fourth thoracic ganglion. Their density values were 256 neurons/mm2 in the cranial cervical ganglion, 250 neurons/mm2 in the vertebral ganglion, 248 neurons/mm2 in the cervicothoracic ganglion and 252 neurons/mm2 in the fourth thoracic ganglion. 相似文献
132.
Isodirectional tuning of adjacent interneurons and pyramidal cells during working memory: evidence for microcolumnar organization in PFC 总被引:9,自引:0,他引:9
Studies on the cellular mechanisms of working memory demonstrated that neurons in dorsolateral prefrontal cortex (dPFC) exhibit directionally tuned activity during an oculomotor delayed response. To determine the particular contributions of pyramidal cells and interneurons to spatial tuning in dPFC, we examined both individually and in pairs the tuning properties of regular-spiking (RS) and fast-spiking (FS) units that represent putative pyramidal cells and interneurons, respectively. Our main finding is that FS units possess spatially tuned sensory, motor, and delay activity (i. e., "memory fields") similar to those found in RS units. Furthermore, when recorded simultaneously at the same site, the majority of neighboring neurons, whether FS or RS, displayed isodirectional tuning, i.e., they shared very similar tuning angles for the sensory and delay phases of the task. As the trial entered the response phase of the task, many FS units shifted their direction of tuning and became cross-directional to adjacent RS units by the end of the trial. These results establish that a large part of inhibition in prefrontal cortex is spatially oriented rather than being untuned and simply regulating the threshold response of pyramidal cell output. Moreover, the isodirectional tuning between adjacent neurons supports a functional microcolumnar organization in dPFC for spatial memory fields similar to that found in other areas of cortex for sensory receptive fields. 相似文献
133.
汉族男子体格及生殖器发育特点 总被引:1,自引:0,他引:1
2411例汉族男性大学生体格和生殖器的测量结果如下:阴茎周径8.17±0.64cm,阴茎长度7.43±1.04cm,阴茎牵长13.33±1.19cm,右睾丸容积17.91±4.09ml,左睾丸容积17.83±4.05ml,身高171.07±5.66cm,体重58.43±7.75kg.北方学生体格和生殖器发育均优于南方.城、县、乡学生的生殖器发育无明显差异,但城市学生体格发育优于农村.16岁后阴茎、睾丸大小变化不大,但生殖器的发育可持续到30岁. 相似文献
134.
应用ABC法、LSAB法对144例乳腺癌及癌旁组织进行了c─erbB─2、p53基因蛋白表达的研究。结果:c─erbB─2表达阳性率为48.6%,浸润性导管癌阳性率最高(74.1%);其表达与肿瘤体积、淋巴结转移、组织分级、核分裂计数、临床分期呈正相关,与雌激素受体(ER)、孕激素受体(PR)状况呈负相关,表达者5年生存率显著低于表达阴性者.因而c─erbB─2表达的检测可作为评估乳腺癌预后的有力指标。p53表达的阳性率为24.7%,髓样癌阳性率较高(38.5%);p53表达与组织分级和淋巴结转移状况呈正相关;阳性率随肿瘤体积增大和临床分期升高而增加;在ER或PR阴性者中p53阳性率高于ER或PR阳性者。本文未发现c─erbB─2与p53表达的相关性;两者表达均阳性者与仅一种阳性者在肿瘤体积、淋巴结转移和临床分期方面差异无显著性。 相似文献
135.
M Grompe N Rao F F Elder C T Caskey F Greenberg 《American journal of medical genetics》1992,42(1):39-43
We present a patient with 45,X/46,X,+r(X) mosaicism and lack of inactivation of either the normal or the ring X in the 46,X,+r(X) cells. The patient has mental retardation, syndactyly, minor facial anomalies, and a congenital heart defect. Although most patients with 45,X/46,X,+r(X) have the Ullrich-Turner syndrome, 2 previously described patients with this karyotype also had a distinct phenotype consisting of severe mental retardation, syndactyly, and abnormal face. The unusually severe phenotype in these patients was thought to be due to lack of X-inactivation of the ring X chromosome. The findings in our patient support this hypothesis. 相似文献
136.
137.
Keiko Murayama Robert S. Greenwood Kathleen W. Rao Arthur S. Aylsworth 《American journal of medical genetics. Part A》1991,40(4):488-492
We have studied three children with de novo terminal deletion of the long arm of chromosome 1 (46,XX,del(1)(q43)). They all have minor anomalies and neurological signs (severe psychomotor developmental delay, generalized hypotonia, and seizures) that have been described previously. In addition, all of these three patients have autistic-like behavior. They avoid eye contact, show no interest in people, express little emotion, and repeat stereotypic movements such as head nodding and purposeless finger manipulation. They also spend excessive time in making unusual sounds consisting of a high-pitched shrill cry with little intonation in infancy and a harsh, strained, and glottal stridency in later life. They make no labial, lingual, or nasal sounds. We suggest that these observations may be unique clinical manifestations of certain terminal 1q deletions. 相似文献
138.
D. C. Rao J. M. Lalouel B. K. Suarez G. Schonfeld C. J. Glueck R. M. Siervogel John M. Opitz 《American journal of medical genetics. Part A》1983,15(2):195-203
Because of its association with longevity and reduced incidence of coronary heart disease, it becomes important to find out how elevated HDL-cholesterol levels are determined. Analyses of family data from Cincinnati initially suggested environmental factors common to sibs; however, some form of dominant inheritance could not be ruled out. Reanalysis of the Cincinnati data by Iselius and Lalouel concluded against a major locus, but did identify three families as possibly segregating for a major locus. Analysis of an additional 26 kindreds from the same population in Cincinnati by Siervogel and associates concluded that a major gene could be causing familial aggregation of high density lipoprotein in white kindreds. In this analysis, we pooled all the white Cincinnati kindreds (n = 31), and investigated the familial transmission using complex segregation analysis. We failed to obtain clear evidence for major locus determination. Under the parsimonious hypothesis of no major locus, the polygenic heritability and common sibling environmental correlation were estimated as 0.531 and 0.263, respectively, consistent with other evidence. 相似文献
139.
140.