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991.
Stimulation of the quisqualate (QA) subtype of glutamate receptor increased the expression of phosphate activated glutaminase (needed for neurotransmitter glutamate synthesis) and the ability to release neurotransmitter glutamate in cultures of glutamatergic cerebellar granule neurons. In contrast, QA had no significant effects on the lactate dehydrogenase activity and amount of protein. The QA-mediated elevation in glutaminase activity was blocked by the ionotropic QA receptor antagonist CNQX and mimicked by the ionotropic QA receptor agonist AMPA, but not by the metatropic QA receptor agonist t-ACPD. The increase in Ca2+ influx essentially through activation of L-type channels, and not the mobilization of internal Ca2+ stores, was responsible for these QA receptor-mediated long-term changes in cerebellar granule neurons. 相似文献
992.
We have reviewed our experience with 118 biliary catheterization procedures in 109 patients from 1979 to 1984. Major complications (septic shock, hemorrhage, subphrenic abscess, and formation of an arteriovenous fistula) occurred in five patients (4.2%), three of whom died (2.5%). Minor complications occurred in 41 patients. Our success rate using the procedure was 97%. The complications that occurred are described. 相似文献
993.
R Testa G Rodriguez F Dagnino A Grasso A Gris S Marenco F Nobili D Risso G Rosadini G Celle 《Journal of clinical pharmacology》1991,31(2):136-139
The current study evaluated the effect of two beta adrenergic-blocking agents, propranolol (PRP) and atenolol (ATN), versus placebo on cerebral blood flow (CBF) of three homogeneous groups of cirrhotic patients with portal hypertension. CBF was measured by the noninvasive 133-Xenon inhalation method at rest and 1 hour after a single oral dose of PRP (40 mg), or ATN (100 mg), or placebo. Blood pressure and heart rate (HR) were measured at the beginning of each examination, and end-tidal pCO2(PeCO2) was monitored. The HR decreased significantly in both the PRP and ATN groups (P less than .01), whereas no changes were recorded for both PeCO2 and mean arterial blood pressure (MABP). The comparisons of the CBF differences among groups (ANOVA with the significance levels adjusted by the Bonferroni's correction) showed a significant increase in CBF after ATN as compared with both placebo (P less than .02) and PRP (P less than .01), whereas no significant differences were seen after PRP as compared with placebo. Our results confirm that PRP does not significantly affect CBF, whereas ATN induces an increase in CBF, although the underlying mechanism is difficult to explain. 相似文献
994.
The pharmacological action of the aqueous extract of PRUNUS SPINOSA L. branches has been studied in tissue preparation IN VITRO. The influence of the extract on rat vas deferens and duodenum was tested using norepinephrine and acetylcholine on spasmogens as well as on guinea pig ileum and taenia coli using histamine and calcium chloride, respectively. The extract reduced responses to norepinephrine, epinephrine and histamine. Responses to cumulative increased Ca (2+) concentrations in depolarizing bathing medium were also blocked. The P. SPINOSA L. extract had effects PER SE on rat vas deferens and guinea pig ileum. 相似文献
995.
Childhood injuries in the United States. A priority issue 总被引:8,自引:0,他引:8
J G Rodriguez 《American journal of diseases of children (1960)》1990,144(6):625-626
996.
Two cycles of MOPP and radiotherapy: effective treatment for stage IIIA and IIIB Hodgkin's disease 总被引:1,自引:0,他引:1
F B Hagemeister L M Fuller W S Velasquez P McLaughlin J R Redman F Swan M A Rodriguez L North D Dixon K Silvermintz 《Annals of oncology》1991,2(1):25-31
Two cycles of MOPP (mechlorethamine, vincristine (Oncovin), procarbazine, prednisone) and radiotherapy were used to treat 197 patients with stage III Hodgkin's disease. Prior to 1980, radiotherapy was delivered to the mantle, abdomen and pelvis; thereafter, pelvic irradiation was deleted for patients with stage III1 disease. Complete remission rates for IIIA and IIIB presentations were 91% and 89%. The 10-year freedom from tumor mortality (FTM) rate for all patients was 81%; for IIIA, it was 87% and for IIIB, it was 72%. Results were not significantly affected by gender, age, pathology, or deletion of pelvic radiotherapy. However, a subgroup of 28 patients with a tumor burden that included pelvic disease who also had B symptoms was identified as having a poor prognosis. Their FTM was 43%, compared with 87% for all other patients combined (P = 0.002). Based on this analysis, we conclude that limited chemotherapy in combination with radiation therapy can yield results similar to programs that use more chemotherapy for all patients with IIIA disease and for most patients with stage IIIB. However, patients with tumor burdens which include pelvic disease and B symptoms require a different approach. 相似文献
997.
M Pe?arrocha Diago F J Silvestre Donat R Rodriguez Gil 《Revue de stomatologie et de chirurgie maxillo-faciale》1990,91(6):477-479
Two cases of anginal pain limited to the mandible with secondary radiation of the pain to the neck and clavicular region are presented. Although the pain was initially diagnosed as odontogenic in origin, further historial workup suggest the suspicion of referred pain from coronary insufficiency. Appropriate medical referral confirmed diagnostic suspicions. Important aspects involved with differential diagnosis of referred anginal pain are also discussed. 相似文献
998.
999.
1000.
Daniel B Ennis Gordon Kindlman Ignacio Rodriguez Patrick A Helm Elliot R McVeigh 《Magnetic resonance in medicine》2005,53(1):169-176
The spatially varying tensor fields that arise in magnetic resonance imaging are difficult to visualize due to the multivariate nature of the data. To improve the understanding of myocardial structure and function a family of objects called glyphs, derived from superquadric parametric functions, are used to create informative and intuitive visualizations of the tensor fields. The superquadric glyphs are used to visualize both diffusion and strain tensors obtained in canine myocardium. The eigensystem of each tensor defines the glyph shape and orientation. Superquadric functions provide a continuum of shapes across four distinct eigensystems (lambda(i), sorted eigenvalues), lambda(1) = lambda(2) = lambda(3) (spherical), lambda(1) < lambda(2) = lambda(3) (oblate), lambda(1) > lambda(2) = lambda(3) (prolate), and lambda(1) > lambda(2) > lambda(3) (cuboid). The superquadric glyphs are especially useful for identifying regions of anisotropic structure and function. Diffusion tensor renderings exhibit fiber angle trends and orthotropy (three distinct eigenvalues). Visualization of strain tensors with superquadric glyphs compactly exhibits radial thickening gradients, circumferential and longitudinal shortening, and torsion combined. The orthotropic nature of many biologic tissues and their DTMRI and strain data require visualization strategies that clearly exhibit the anisotropy of the data if it is to be interpreted properly. Superquadric glyphs improve the ability to distinguish fiber orientation and tissue orthotropy compared to ellipsoids. 相似文献