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991.
James W. Verbsky Mary K. Hintermeyer Pippa M. Simpson Mingen Feng Jody Barbeau Nagarjun Rao Carlyne D. Cool Luis A. Sosa-Lozano Dhiraj Baruah Erin Hammelev Alyssa Busalacchi Amy Rymaszewski Jeff Woodliff Shaoying Chen Mary Bausch-Jurken John M. Routes 《The Journal of allergy and clinical immunology》2021,147(2):704-712.e17
992.
Zhang B van Adel BA Gabriele J Duong M Henry P Ball AK Mishra RK 《Journal of chemical neuroanatomy》2002,24(1):2248-48
Catecholamine regulated protein 40 (CRP40) has been shown to be expressed in the central nervous system (CNS) of several mammalian species where it may function in a similar manner to members of the heat shock protein (HSP) family. Immunohistochemical and immunoblotting techniques were utilized to investigate whether CRP40 is expressed in normal rat retinas. In addition, changes in CRP40 expression were studied following optic nerve transection. The immunohistochemical results showed that CRP40 is expressed in the normal rat retina. The protein was found to be highly expressed in the ganglion cell layer (GCL), the inner nuclear layer (INL) and the outer plexiform layer (OPL). In addition, a low level of CRP40 was found in the inner plexiform layer (IPL), and in the inner segment layer (ISL). No expression was found in the outer nuclear layer (ONL) of normal rat retina. The immunoblotting results show that CRP40 expression decreased in a time-dependent fashion after the optic nerve transection. This decrease indicates that the expression of CRP40 is dependent on the neuron's normal physiological state and that it plays an important function in physiological and pathological conditions in the retina. 相似文献
993.
人胎儿中枢神经系统星形胶质细胞形态发育的观察 总被引:4,自引:0,他引:4
为观察人胎儿中枢神经系统星形胶质细胞形态发育。用胶质原纤维酸性蛋白抗体进行免疫组织化学染色。结果表明;1.以颈段脊髓,脑干,海马和小脑蚓部于胚胎25周其GFAP染色强度,细胞密度接近出生时水平。而此时期大脑皮层Ast密度约为出生时的四分之一。2.在同一胎龄CNS的不同部位,GFAP阳性Ast分布不均匀。3.Ast不仅在毛细胞血管周围,而且在小血管周围密度大染色深,环绕血管呈辐射状排列。 相似文献
994.
强永刚 《现代临床医学生物工程学杂志》1996,(1)
用国产Na~(125)I源、氯胺-T法、制备(-)~(125)I心得静标记配体【(-)~(125)I-IPIN】,放射色谱法分离复合物,测得(-)_(125)I-IPIN的Rf值为0.35,比活度为46.12~55.32TBq/mmol,标记率为37%,放射化学纯度达95%以上,该标记配体与小鼠脑细胞膜β受体的结合用受体的放射配体结合分析法(RBA)考核,呈典型的饱和曲线,Scatchard分析呈一直线,平衡解离常数(Kd)为0.041±0.001nM,Hill系数接近于1(0.99)。 相似文献
995.
M. Wittner A. Di Stefano B. Mandon N. Roinel C. de Rouffignac 《Pflügers Archiv : European journal of physiology》1991,419(2):212-214
The effect of antidiuretic hormone (ADH) on transepithelial Na+, Cl–, Ca2+ and Mg2+ net fluxes (JNa, JCl, JMg, JCa) was investigated in isolated perfused cortical thick ascending limb segments (cTAL) of the mouse nephron, using the microperfusion technique and the electron microprobe analysis to determine the ionic composition of the collected tubular fluid. Simultaneously, the transepithelial potential difference (PDte) and the transepithelial resistance (Rte) were recorded. Prior to the flux measurements cTAL segments were perfused for one hour. During this equilibration period PDte decreased significantly from +19.9±1.6 to +14.9±1.l mV and Rte increased from 30.6±3.5 cm2 to 38.8±2.4 cm2 (n=7), reflecting a decline in NaCl transport. After ADH was added to the bath solution at 10–10 mol.l–1, PDte increased from +14.4±1.1 to +18.0±1.5 mV, accompanied by a rise in JNa and JCl from 205±11 to 273±19 and from 216±12 to 283±21 pmol.min–1.mm–1 (n=7), respectively. JCa and JMg also increased from 0.81±0.07 to 1.50±0.12 and from 0.43±0.11 to 0.76±0.08 pmol.min–1.mm–1 (n=7), respectively. All these effects were fully reversible after withdrawal of the hormone. In conclusion our data indicate that ADH stimulates divalent cation transport and NaCl transport in the cortical thick ascending limb of Henle's loop of the mouse. 相似文献
996.
A rapidly inactivating Ca2+-dependent K+ current in pheochromocytoma cells (PC12) of the rat 总被引:13,自引:0,他引:13
The membrane electrical properties of undifferentiated pheochromocytoma cells of the rat (PC12) were studied using both current-and voltage-clamp techniques with the use of low-resistance blunt-tipped micropipettes (patch electrodes). In the presence of tetrodotoxin (TTX, 2–3 M), a spike-like wave form with a prominent after-hyperpolarization (AHP) was recorded following brief (< 10 ms) depolarizing current pulses. The inorganic divalent cations, Cd2+ (0.5 mM), Mn2+ (4mM), and 0 mM Ca2+/4 mM Mg2+ solution prolonged the duration, attenuated the AHP, slowed the rate of repolarization, and slightly enhanced the amplitude of this wave form. A rapidly inactivating outward current was recorded in over 70% of the cells under voltage-clamp conditions. This transient current was elicited at about ±30 mV, and was blocked by tetraethylammonium (5 mM), inorganic divalent cations (Cd2+, 0.5 mM; Mn2+, 4 mM; Ba2+, 3 mM), and removal of Ca2+ (0 mM Ca2+/4 mM Mg2+) from the local perfusion medium. In addition, 4-aminopyridine (5 mM), which blocks the transient outward K+ current IA in a variety of excitable cells, did not have any appreciable effect on this rapidly inactivating current. Moreover, it was possible to elicit the current at a holding potential of ±40 mV. The reversal potential of this current was ±90 mV, and shifted positively when extracellular K+ concentrations were elevated. It is concluded that PC12 cells have a rapidly inactivating Ca2+ -dependent K+ current. A possible explanation for the transient nature of this current may be the presence of an effective intracellular Ca2+ buffering (uptake or extrusion) system. 相似文献
997.
To non-invasively determine abdominal aortic properties, a five-element lumped circuit model was adopted. The model consists
of resistance due to blood viscosity (R1), inertia of blood flow, compliances of the vessel (C1, C2), resistance of the peripheral
arteries (R2) and the impedance of the femoral arteries (termination). Patterns of the central velocity of the upper abdominal
aorta and the femoral artery are measured by pulsed Doppler echocardiography, and confours of flow volume rates are calculated.
The pressure pattern of the lower limb is recorded by a pulse wave rransducer and corrected according to sphygmomanometer
values. Contours are transformed into respective Fourier transform components. The current transfer function is described
theoretically and calculated from the acquired Fourier components. Values of every element are evaluated by the nonlinear
least squares method. In 94 subjects (17–92 years), the values of each element are estimated. R2 values are greater in the
elderly group, than in the young group and r1 (R1/cm) increased with age. This model demonstrates that vessel compliance (c1+c2 (C1+C2/cm)) decreases with age, and it is suggested that this may be a useful marker of arteriosclerosis. 相似文献
998.
An interactive, minicomputer system has been constructed for analyzing dynamic phenomena recorded on movie film in a developmental biology laboratory. The minicomputer interfaces a stop-motion, variable speed projector, a digitizing pen, and real-time graphics display equipment. An analyst uses the pen to digitize features in a film, e.g. by following a cell. A computer-generated animation portraying all data entered is superimposed on the film image and synchronized with it. Noteworthy system features include: image overlays on a large screen, data entry with the projector running, large data capacity, computer control of the projector, and convenient data entry tools. 相似文献
999.
Charles H. Bombardier George W. Divine John S. Jordan W. Blair Brooks Francis A. Neelon 《Journal of behavioral medicine》1993,16(5):467-484
Cluster analysis of the MMPI has been utilized widely in the chronic low back pain literature to try to identify reliable patient subtypes predictive of treatment outcome. We extended this methodology to patients with heterogeneous chronic medical conditions by replicating prototypic MMPI cluster group profiles and by relating cluster groups to clinical baseline and outcome data. Subjects were two independent samples (n=254 and n=263) of chronically ill patients admitted to an inpatient medicine/psychiatry unit. Using a four-cluster solution, similar cluster profile groups were replicated in both samples. Consistent differences emerged between cluster groups on functional impairment, psychiatric diagnoses, depression, and psychosomatic symptoms. Cluster group membership also predicted changes in functional impairment and depression six months after treatment. Results are discussed in terms of similarities between chronic low back pain and chronic illness and tailoring treatment to different patient types.This research was supported in part by a grant from the Henry J. Kaiser Family Foundation. 相似文献
1000.
Differences in cytokine secretion by intestinal mononuclear cells, peripheral blood monocytes and alveolar macrophages from HIV-infected patients. 总被引:2,自引:1,他引:2
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M Steffen H C Reinecker J Petersen C Doehn I Pflüger A Voss A Raedler 《Clinical and experimental immunology》1993,91(1):30-36
Mononuclear cells of the lamina propria (LpMNC), isolated from endoscopically taken biopsies of the large bowel from AIDS patients, were analysed for their ability to secrete tumour necrosis factor-alpha (TNF-alpha), IL-1 beta and IL-6. Stimulation of LpMNC from normal controls with pokeweed mitogen (PWM) led to a time- and dose-dependent enhancement of TNF-alpha, IL-1 beta and IL-6 secretion. In contrast, PWM stimulation of LpMNC from AIDS patients resulted in only a small increase in TNF-alpha release. Constitutive secretion of IL-1 beta and IL-6 in these patients was already increased to the concentration range of stimulated cells from normal controls and could not be further increased, probably due to maximal in vivo stimulation. Secretion of TNF-alpha, IL-1 beta and IL-6 by peripheral blood monocytes (PBM) and alveolar macrophages from AIDS patients was elevated with or without stimulation compared with normal controls. Obviously, the regulation of TNF-alpha secretion is dependent on the microenvironment. Since it is known that interferon-gamma (IFN-gamma) may induce the production of TNF-alpha, the secretion of this cytokine was examined. Release of IFN-gamma was constitutively and under stimulation lowered in LpMNC from AIDS patients compared with normal controls. Addition of IFN-gamma to LpMNC did not result in enhanced TNF-alpha secretion. Our data indicate a defective function of intestinal mononuclear cells in AIDS patients as shown by the diminished TNF-alpha secretion. 相似文献