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81.
Tocopherol-associated protein (TAP) was expressed in mouse mast cells. TAP was predominantly localized in the cytoplasm, and the subcellular localization was not changed by alpha-tocopherol. The results suggest that the physiological role of TAP in mast cells is not regulation of tocopherol function but an as-yet-unidentified activity.  相似文献   
82.
We analyzed the genetic aberrations on chromosome arms 1p, 10q, and 14q, which are thought to be loci that include putative tumor suppressor genes in meningiomas. We initially conducted molecular genetic testing on a total of 72 tumors including 15 atypical and 8 anaplastic meningiomas using double-target fluorescence in situ hybridization. An incidence of deletion of 1p was observed in 16.3% of histologically benign, 86.7% of atypical, and 87.5% of anaplastic meningiomas. Microsatellite analysis for loss of heterozygosity on 1p, 10q, and 14q was performed in 15 tumors (6 benign, 6 atypical, and 3 anaplastic meningiomas). We detected a limited deleted region on 1p36 in two tumors and suggest a new consistent region of deletion at 1p36.21p23 distal to D1S507 and proximal to D1S214, which spans 8.21 megabases. In addition, loss of 10q was detected in two of three secondary atypical meningiomas, and loss of 14q in two of three primary anaplastic meningiomas. We suggest that one of the putative suppressor genes is located at 1p36.21p23, and that 10q loss may contribute to the malignant progression from benign to atypical meningiomas.  相似文献   
83.
The paper presents an evaluation of the possibility of using fetal magnetocardiogram (FMCG) signals to estimate and classify the accessory pathway in fetal Wolff-Parkinson-White (WPW) syndrome. The FMCG signals of two fetuses with WPW syndrome (type A) were detected using a 64-channel superconducting quantum-interference device system. An average across the cycles of these signals was taken to obtain clear WPW signals. To determine the direction and position of the accessory pathway in a fetal heart accurately, the accessory pathway and activated pathway at the peak of the QRS complex thus obtained were estimated for each fetus, using a single-dipole model. The phase angle (about 90o) between the equivalent current dipoles (ECDs) was the same for both fetuses. This angle suggested that the accessory pathway is in the left side of the heart, i.e. that the pathway exists in the position of the accessory pathway in a fetus with WPW syndrome from the angle between the ECD of the accessory pathway and the ECD of the peak in the QRS complex was thus demonstrated.  相似文献   
84.
The musk shrew, Suncus murinus, is one of the primitive mammals and has a pair of palatine tonsils. In the present study, we investigated the blood microvascular architecture of the tonsil in this animal by scanning electron microscopy of corrosion casts. The paranodular arterioles entered the lymph nodule to form a coarse capillary plexus within the nodule. Some of the arterioles reached the dome region to give rise to a fine meshwork of dome subepithelial capillaries. This dome subepithelial capillary network did not show any hairpin or switch-back patterns, as seen in human and rabbit tonsils. Both of the nodular and dome capillaries were drained into the postcapillary venules in the periphery of the nodular or the paranodular region. On the surface of these cast venules, oval-shaped indentations were seen corresponding to the luminal surface of the high endothelial venules. These venules were collected into the large vein at the bottom of the tonsil. The blood vascular architecture of the musk shrew tonsil is basically the same as those of other mucosa-associated lymphoid tissues in mammals.  相似文献   
85.
Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials.  相似文献   
86.
S Murakami  Y Arai 《Neuroscience letters》1989,102(2-3):185-190
Neonatal treatment of female rats with androgen decreases the nuclear volume of the anteroventral periventricular nucleus of the preoptic area (AVPv-POA). In order to examine the effect of androgen on the neural substrates in the developing AVPv-POA which show a sexual dimorphism in nuclear volume, the cell death pattern in the AVPv-POA was compared between normal females and androgenized females. Wistar female rats were treated with 50 micrograms of testosterone propionate (TP) for 5 days from the day of birth. Degenerating cells (pyenotic cells) and normal cells were counted in every third section from days 1 to 13 of life. The rate of pycnotic cells to 1000 cells in TP-treated females sacrificed at days 7 and 10 was significantly higher than that in normal females. These results may suggest that neonatal androgen regulates neuronal death in the AVPv-POA, decreasing the number of neurons in the nucleus.  相似文献   
87.
88.
To characterize the medullary temperature-responsive neurones in rabbits, statistical analysis of interspike intervals was performed on 24 neurones recorded at various temperatures of the medulla. It was found that the medullary neurone fired at a relatively regular interval and 11 of 24 neurones displayed an invariable precision in thermoreception over a broad range of medullary temperatures; also, that the temporal distribution of interspike intervals of medullary neurones was markedly different from that of hypothalamic neurones.  相似文献   
89.
The distribution of functionally active monoamine oxidase type A (MAO-A) was investigated by in vivo quantitative autoradiography using [14C]clorgyline in normal, conscious rat brain. [14C]clorgyline was synthesized by the methylation reaction of N-desmethylclorgyline using [14C]methyliodide. Sixty minutes after [14C]clorgyline administration (1.58 MBq/animal i.v.), the brains were removed and prepared for autoradiography by washing the brain sections with 5% trichloroacetic acid solution to remove the nonbinding free tracer. The amount of MAO-A was calculated from the regional acid-insoluble tissue radioactivity and the specific activity of the tracer. The highest amount of MAO-A (5.84 nmol/g tissue) was found in the locus coeruleus. The interpeduncular nucleus, habenular nucleus, fasciculus retroflexus, and solitary tract nucleus possessed over 1.6 nmol/g tissue of MAO-A. Among 23 regions of interest, the lowest amount of MAO-A (0.37 nmol/g tissue) was found in the globus pallidus. The findings of this study suggest that the pattern of MAO-A parallels both in neuroanatomical distribution and in density that of norepinephrine and serotonin innervation. The MAO-A concentration was, however, relatively low in the dopamine-related areas. This corresponded to the previous results obtained by histochemical analysis. In addition, among the white matter structures, a high amount of MAO-A was found specifically in the fasciculus retroflexus.  相似文献   
90.
The corticorubral projections in adult cats are primarily uncrossed. However, early in development and after early unilateral lesions of the sensorimotor cortex, crossed corticorubral projections are also observed. The present study was performed to disclose (1) whether the crossed projections originate from neuronal subpopulations different from those producing uncrossed ones and (2) how the neurons that give rise to the crossed projections in the lesioned animals are related to those occurring in normal development. We injected fluorescent latex microspheres into the red nucleus of two groups of animals: (1) intact kittens at postnatal week 3 and (2) kittens that had received unilateral ablation of the cerebral cortex at this stage and were then allowed to survive for at least 4 weeks. Red fluorescing microspheres were injected on one side and green ones on the other. In both normal and lesioned kittens, a number of cells in the cortex were labeled as a result of the contralateral as well as the ipsilateral injections, and no difference in size or distribution was found between the cells labeled from contralateral and ipsilateral injections. More than half of the cells labeled from contralateral injections were double-labeled in both groups of animals. These results indicate that individual corticorubral cells project bilaterally in normal development as well as following unilateral lesions of the cortex. With respect to the cells producing crossed projections, they were similar in both laminar and regional distributions between the intact and lesioned animal, suggesting that the crossed projections arise from the same neuronal subpopulation before and after cortical lesions. This view was supported by sequential injections of the tracers, which indicated that cells normally projecting contralaterally maintained the crossed projection after the lesions. Taking into account our previous observations that growth and proliferation of crossed corticorubral axons took place in the red nucleus (Murakami et al. 1991a), it is likely that growth and proliferation of the axons in denervated targets play a major role in lesion-induced establishment of aberrant projections.  相似文献   
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