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131.
Identification of the C-terminal flanking peptide of preprocholecystokinin in rat brain by a novel radioimmunoassay 总被引:1,自引:0,他引:1
The C-terminal flanking peptide of preprocholecystokinin (preproCCK) has been identified in extracts of rat brain using a novel radioimmunoassay. There is a single form of immunoreactive material on gel filtration, ion exchange and reversed-phase HPLC. The C-terminal preproCCK immunoreactivity had a similar pattern of distribution to CCK8 in different regions of rat brain. This assay should help in studies of neuronal CCK biosynthesis. 相似文献
132.
Histoplasmosis is a fungal disease that affects humans and is caused by Histoplasma capsulatum. The presentation of the infection may be acute, chronic, or disseminated. The disseminated form has extrapulmonary manifestations which may include oral manifestation a. A patient with AIDS sought treatment and he had disseminated histoplasmosis with oral manifestations. The purpose of this case report and literature review is to emphasize the role the dental team has in the diagnosis of disseminated disease when a patient presents with oral manifestations associated with the disease. This case report is clinically relevant because it is not uncommon for oral manifestations to be one of the first signs of systemic disease. 相似文献
133.
D. A. CROOKS 《Neuropathology and applied neurobiology》1991,17(5):421-424
The quantitation of diffuse axonal injury provides a more objective approach to the assessment of tissue damage in head injuries. The method designed in this study takes into account the anisotropy and structural inhomogeneity of the brain, and the distribution of lesions in diffuse axonal injury. The number of counts required for the statistical analysis is inversely proportional to the square of the desired accuracy, specified as the percentage of the mean value of the axonal balloons since the true mean is unknown from the outset. The number of fields are examined using an indexed-squares graticule in 10 different areas of the brain. Silver-stained sections from the brains of head injured patients that survived longer than 12 h must be used with this method. Difficulties may arise when patients of different survival times are compared since it takes some time for the axonal balloons to develop. A correlation with the survival time can be established with the quantitative data collected. The morphometric principles and the statistical rationale on which this methodology is based are briefly presented. 相似文献
134.
Manfred Schmidt Leslie Van Ekeris Barry W. Ache 《The Journal of comparative neurology》1992,318(3):277-290
The organization of sensory afferents in the antennular nerve (AN) of the spiny lobster and the central arborization of the afferents in the lateral and medial antennular neuropils (LAN, MAN) were analyzed by backfilling the AN with biocytin. The MAN receives primarily thick afferents (diameter ≥ 10 μm) with a consistent pattern of arborization from the medial of the three major divisions of the AN. The LAN, in contrast, receives many thin to medium-sized afferents (diameter ≤ 0.3–5 μm), in addition some with diameters ≥ 5 μm, from the lateral and dorsal divisions of the AN. In contrast to the consistent pattern of arborization in the MAN, afferents projecting to the LAN arborize in widely different patterns. Serially arranged, orthogonal side branches that are suggestive of topographical representation of the serially arranged sensilla on the antennule contribute to the stratification of the LAN. Together with existing electrophysiological data, these morphological findings are consistent with the idea that the MAN receives primarily mechanosensory (largely statocyst) input, as previously thought, but that the LAN receives chemosensory as well as mechanosensory input. The chemosensory input to the LAN would represent a novel pathway for processing chemosensory input from the antennule. 相似文献
135.
O. Pranevicius K. Bertasius M. Pranevicius E. Jarzemskas 《Acta neurologica Scandinavica》1992,86(5):512-516
The dynamics of the speed of transcranial propagation of ultrasonic impulses has been established in humans. The possibility of detecting the changes in mechanical state of intracranial structures by dynamic measurement of the time of transcranial propagation of ultrasonic impulses (TUPT) has been ascertained for 10 healthy persons and 11 patients with different neurological pathology. The cerebrospinal fluid pressure (CSFP) was simultaneously monitored for 4 of the patients. Spontaneous fluctuations in TUPT and the changes caused by jugular veins, inferior vena cava compression, hyperventilation and temporary retention of breathing were detected for all investigated subjects. Spontaneous TUPT changes in the range of 0.25-0.85 x 10(-4) of initial mean value, which are related with cardiac and respiratory cycles, have been found in healthy persons while in patients they ranged from 0.07 x 10(-4) to 4.5 x 10(-4) of mean time. In healthy persons bilateral jugular vein compression leads to a decrease in TUPT by 1.8-3.0 x 10(-4), while the compression of inferior vena cava gives an increase in TUPT by 1.6-2.6 x 10(-4). Changes in TUPT during these maneuvers in neurological patients were found to be of different amplitude and direction. The rise of CSFP by 8.4-20.2 mmHg (mean 12.4 mmHg) was observed in 4 investigated patients during the compression of jugular veins or during the inferior vena cava compression, while the changes in TUPT obtained during each of such maneuvers were of opposite character. The results suggest that dynamic evaluation of acoustic impedance of intracranial system reflects the changes in the mechanical state of brain parenchyma. 相似文献
136.
Perfusion is a crucial physiological parameter for tissue function. To obtain perfusion-weighted images and consequently to measure cerebral blood flow (CBF), a newly developed flow-sensitive alternating inversion recovery (FAIR) technique was used. Dependency of FAIR signal on inversion times (TI) was examined; signal is predominantly located in large vessels at short TI, whereas it is diffused into gray matter areas at longer TI. CBF of gray matter areas in the human brain is 71 ± 15 SD ml/100 g/min (n = 6). In fMRI studies, micro- and macrovessel inflow contributions can be obtained by adjusting TIs. Signal changes in large vessel areas including the scalp were seen during finger opposition at a TI of 0.4 s; however, these were not observed at a longer TI of 1.4 s. To compare with commonly used BOLD and slice selective inversion recovery techniques, FAIR and BOLD images were acquired at the same time during unilateral finger opposition. Generally, activation sites determined by three techniques are consistent. However, activation of some areas can be detected only by FAIR, not by BOLD, suggesting that the oxygen consumption increase couples with the CBF change completely. Relative and absolute CBF changes in the contralateral motor cortex are 53 ± 17% SD (n = 9) and 27 ± 11 SD ml/100 g/min (n = 9), respectively. 相似文献
137.
大剂量地塞米松及SOD在实验性脑损伤中的治疗作用 总被引:1,自引:0,他引:1
大剂量地塞米松和SOD是外伤性脑继发性损害药物治疗的新方案。本实验在豚鼠局灶性脑损伤模型上试用该两种药物,通过脑含水量、灶周伊文斯兰渗出、血CK、Ca和LDH含室及光镜和电镜病理检查等指标。 相似文献
138.
Changes in the content of the opiate peptide Met-enkephalin at the early stages of immune response are studied in different
structures of rats brain 20 min and 24 h after immunization with sheep erythrocytes.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 2, pp. 170–172, February, 1997 相似文献
139.
国人脑内某些解剖结构定位研究与临床应用 总被引:1,自引:0,他引:1
本文通过对45个正常成人脑标本进行三维连续2mm切片,对Forel-H,隔区等九个脑内重要结构的解剖坐标及毗邻关系进行观测,为立体定向手术提供解剖学依据。55例临床实践证明手术疗效比较满意。 相似文献
140.