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991.
Dr. Reed P. Warren Nadine C. Margaretten Nancy C. Pace Ann Foster 《Journal of autism and developmental disorders》1986,16(2):189-197
We have begun an investigation on the immune systems of patients with autism in attempt to determine if immune mechanisms are involved in the development of this severe developmental disorder. A study of 31 autistic patients has revealed several immune-system abnormalities, including reduced responsiveness in the lymphocyte blastogenesis assay to phytohemagglutinin, concanavalin A, and pokeweed mitogen; decreased numbers of T lymphocytes; and an altered ratio of helper to suppressor T cells. Immune-system abnormalities may be directly related to underlying biologic processes of autism, or these changes may be an indirect reflection of the actual pathologic mechanism.The authors gratefully recognize W. Louise Warren, R.N., for assisting with the blood drawings in these studies, and the Utah Society for Autistic Children and Adults for help in obtaining the cooperation of the patients. This work was supported by the Stallone Fund for Autism Research. 相似文献
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Pelvic masses in pregnant patients: MR and US imaging 总被引:1,自引:1,他引:0
Sixteen pregnant patients with pelvic masses detected with ultrasound (US) were studied with magnetic resonance (MR) imaging at 0.35 T. Two patients were in their first trimester, eight in the second, and six in the last. On MR images, 34 masses were seen, including 19 uterine leiomyomas. With US, 20 masses were detected. All masses not seen with US were leiomyomas. Only 20 masses (in 11 patients) were removed for histologic study. In nine cases, MR imaging and US provided similar information on the origin, extent, and type of mass. In seven patients, MR imaging contributed additional information. MR imaging depicted more leiomyomas than US in three patients. In another case, MR images showed that a mass depicted with US was actually a loop of bowel. MR images allowed differentiation between a solid soft-tissue mass and a hemorrhagic fluid-containing mass, correctly depicted the presence of an abdominal pregnancy, and allowed evaluation of the parametrium for spread of cervical carcinoma. 相似文献
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The phenomenon of catch-up growth has been known for a long time but its actual stimulus has remained unidentified. Involvement of growth hormone (GH) seems likely, but it is unknown whether normal GH secretion is an absolute prerequisite for catch-up growth. We present insight to this topic by describing a child with GH deficiency who showed a biphasic pattern of catch-up growth. During the first catch-up phase, she showed restricted catch-up growth in the absence of GH therapy, while she achieved nearly complete catch-up with GH therapy. Both periods of catch-up growth are compared separately with the response to GH therapy of age-matched, GH deficient patients with similar height deficit. This observation suggests that the first phase of catch-up growth in a child with severe growth retardation may be partially GH independent, while further catch-up requires normal GH levels. 相似文献
995.
阿托品对兔胸主动脉平滑肌收缩和细胞增殖的影响 总被引:1,自引:0,他引:1
用兔胸主动脉条研究Atr,Ver对CaCl2,Atr对KCI量—效反应的影响。观察到Atr和Ver能抑制2种激动剂所致兔主动脉条的收缩,量一效曲线右移,最大反应降低,其pD2值分别为4.4和5.8。两药也能明显抑制NE依内Ca2+性收缩,Atr对NE依外Ca2+性收缩影响较小,说明Atr主要对细胞外Ca2+经PDC所致的收缩有抑制作用。在兔ASMC培养中,有Ca2+时,Atr抑制ASMC增殖,无Ca2+时,Atr 20.6~185.2 μmol/L表现刺激增殖,555.7~1666.7 μmol/L则抑制MSMC增殖,说明Atr对ASMC作用也与Ca(2+)有关。 相似文献
996.
R. Bordet P. Verwaerde MA Tran MA Marques JL Montastruc and JM Senard 《Fundamental & clinical pharmacology》1997,11(3):237-244
Summary— This paper investigates the effects of octreotide (0.1 mg/kg, subcutaneous) on cardiovascular adaptation during head-up tilt test in an experimental model of neurogenic orthostatic hypotension (OH) obtained by chronic sinoaortic denervation in anaesthetized dogs. Blood pressure (BP), heart rate (HR), spectral variability (Fast Fourier transformation on 512 consecutive points, Δt: 2 Hz) and plasma catecholamine levels were measured in a double blind cross-over randomized study versus placebo, in supine position and during a head-up tilt test (80°, 10 min) in six sinoaortic denervated and six control (normal) dogs. In normal dogs, head-up tilt test significantly increased HR and diastolic blood pressure (DBP). Plasma noradrenaline levels and energy of the low frequency band (40–150 mHz) of systolic blood pressure (SBP) significantly increased whereas the energy of the low frequency band of HR significantly decreased. Placebo and octreotide failed to modify supine and head-up tilt values of the measured parameters (except the value of low frequency band of SBP, which increased after octreotide). In sinoaortic denervated dogs, supine values of BP, HR and plasma noradrenaline levels were significantly higher than in controls whereas the energy of the low frequency spectral band of HR and SBP was similar to controls. Head-up tilt test induced a dramatic decrease in BP. HR, plasma noradrenaline levels and energy of the low frequency band of SBP and HR remained unchanged during head-up tilt tests. Neither supine nor head-up tilt values of these parameters were modified 45 min after octreotide or placebo administration. These results show that sinoaortic denervation is a reproducible model of OH characterized by a lack of activation of sympathetic efferent pathways during head-up tilt tests. Octreotide, at the dose used, remains ineffective to prevent the fall in BP under these experimental conditions. 相似文献
997.
Cerebral CT venography 总被引:22,自引:0,他引:22
Casey SO; Alberico RA; Patel M; Jimenez JM; Ozsvath RR; Maguire WM; Taylor ML 《Radiology》1996,198(1):163
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