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11.
12.
J L Arriza T M Dawson R B Simerly L J Martin M G Caron S H Snyder R J Lefkowitz 《The Journal of neuroscience》1992,12(10):4045-4055
The beta-adrenergic receptor kinase (beta ARK) phosphorylates the agonist-occupied beta-adrenergic receptor to promote rapid receptor uncoupling from Gs, thereby attenuating adenylyl cyclase activity. Beta ARK-mediated receptor desensitization may reflect a general molecular mechanism operative on many G-protein-coupled receptor systems and, particularly, synaptic neurotransmitter receptors. Two distinct cDNAs encoding beta ARK isozymes were isolated from rat brain and sequenced. The regional and cellular distributions of these two gene products, termed beta ARK1 and beta ARK2, were determined in brain by in situ hybridization and by immunohistochemistry at the light and electron microscopic levels. The beta ARK isozymes were found to be expressed primarily in neurons distributed throughout the CNS. Ultrastructurally, beta ARK1 and beta ARK2 immunoreactivities were present both in association with postsynaptic densities and, presynaptically, with axon terminals. The beta ARK isozymes have a regional and subcellular distribution consistent with a general role in the desensitization of synaptic receptors. 相似文献
13.
Posttraumatic cerebral arterial spasm: transcranial Doppler ultrasound, cerebral blood flow, and angiographic findings. 总被引:33,自引:0,他引:33
N A Martin C Doberstein C Zane M J Caron K Thomas D P Becker 《Journal of neurosurgery》1992,77(4):575-583
Thirty patients admitted after suffering closed head injuries, with Glasgow Coma Scale scores ranging from 3 to 15, were evaluated with transcranial Doppler ultrasound monitoring. Blood flow velocity was determined in the middle cerebral artery (MCA) and the intracranial portion of the internal carotid artery (ICA) in all patients. Because proximal flow in the extracranial ICA declines in velocity when arterial narrowing becomes hemodynamically significant, the extracranial ICA velocity was concurrently monitored in 19 patients. To assess cerebral perfusion, cerebral blood flow (CBF) measurements obtained with the intravenous 133Xe technique were completed in 16 patients. Vasospasm, designated as MCA velocity exceeding 120 cm/sec, was found in eight patients (26.7%). Severe vasospasm, defined as MCA velocity greater than 200 cm/sec, occurred in three patients, and was confirmed by angiography in all three. Subarachnoid hemorrhage (SAH) was documented by computerized tomography in five (62.5%) of the eight patients with vasospasm. All cases of severe vasospasm were associated with subarachnoid blood. The time course of vasospasm in patients with traumatic SAH was similar to that found in patients with aneurysmal SAH; in contrast, arterial spasm not associated with SAH demonstrated an uncharacteristically short duration (mean 1.25 days), suggesting that this may be a different type of spasm. A significant correlation (p less than 0.05) was identified between the lowest CBF and highest MCA velocity in patients during the period of vasospasm, indicating that arterial narrowing can lead to impaired CBF. Ischemic brain damage was found in one patient who had evidence of cerebral infarction in the territories supplied by the arteries affected by spasm. These findings demonstrate that delayed cerebral arterial spasm is a frequent complication of closed head injury and that the severity of spasm is, in some cases, comparable to that seen in aneurysmal SAH. This experience suggests that vasospasm is an important secondary posttraumatic insult that is potentially treatable. 相似文献
14.
The present study focuses on deepening our understanding, from a clinical perspective, of the psychological processes of cancer patients. Through a qualitative analysis of speech, the authors investigate the major organizing and structuring factors of the cancer experience: the lived body, acting in the world, the bond with others, temporal experience and the “other self”. This breakdown of factors, however, proves to be an inadequate approach. Only a clinical approach can ensure the patient receives the focused listening that is key. 相似文献
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16.
P. Satz K. Zaucha D. L. Forney C. McCleary R. F. Asarnow R. Light H. Levin D. Kelly M. Bergsneider D. Hovda N. Martin M. J. Caron N. Namerow D. Becker 《Brain injury : [BI]》1998,12(7):555-567
Traumatic brain injury (TBI) subjects at Glasgow Outcome Scale levels 3 (severe disability), 4 (moderate disability), 5 (good recovery), and an other injury control group (OIC) were compared in terms of neuropsychological, psychosocial, and vocational functioning 6 months after injury. Subjects were a sample of 100 patients with a moderate to severe traumatic brain injury (TBI) and a matched sample of 30 other injury control subjects (OIC) enrolled in the UCLA Brain Injury Research Center study of TBI outcome. Overall, the results showed a systematic decrease in mean neuropsychological test performance as a function of increasing GOS severity, as well as an increased prevalence of symptoms of depression and lower ratings on measures assessing employability and capacity for self care. TBI patients in the 'severe' and 'moderate disability' groups were distinctly inferior to the 'good recovery' and 'OIC' groups, who were quite similar to each other in terms of cognitive, psychosocial, and vocational outcomes. The results demonstrate overall support for the predictive and concurrent validity of the GOS 6 months post injury. Despite these results, which strengthen the utility and appeal of the GOS for multicentre studies, concerns still remain regarding GOS category 4 (moderate disability), which was shown to lack sufficient discriminability in this study. 相似文献
17.
Maslin J Rogier C Berger F Khamil MA Mattera D Grandadam M Caron M Nicand E 《Journal of acquired immune deficiency syndromes (1999)》2005,39(2):129-132
During a national survey in 2002 in Djibouti, serum samples were collected using a valid sampling scheme from 2423 Djiboutians representing the general population of urban and rural districts. The HIV-1 seroprevalence was 2%. The HIV-1 polymerase gene from 53 untreated patients was amplified. Phylogenetic analysis of 34 isolates revealed a majority of subtype C (73%) as well as other subtypes, including CRF02_AG recombinants (18%), subtype D (6%), and subtype A (3%). 相似文献
18.
E. Brambilla S. Gazzeri D. Moro C. Caron de Fromentel V. Gouyer M. Jacrot C. Brambilla 《The American journal of pathology》1993,143(1):199-210
Immunohistochemical analysis of p53 protein was carried out on 95 lung carcinomas from all histological types, including 60 primary tumors, 35 lymph node metastases, and 36 corresponding nude mice xenografts, using four antibodies: PAb240 specific for some mutant conformations; PAb421, PAb1801, and CM1 reactive with most of the forms of p53. Nuclear staining with at least two of those four antibodies revealed the presence of an accumulated protein, considered as indicative of a missense mutation in the p53 gene, in 50% of primary tumors of all histological types, except carcinoids. Some defect of messenger RNA expression was detected by Northern blot analysis in an additional 26% of tumors. p53 immunophenotype of the original tumor was fairly maintained on nude mice. p53 accumulation was not correlated with survival, but with disease extension (P = 0.01). Finally, immunohistochemical analysis allowed the recognition of p53 mutant immunophenotype in 41% of tumors where p53 DNA and messenger RNA were apparently normal, using standard molecular biology. Thus, this method provides a rapid and efficient approach for studying p53 mutations leading to an accumulated protein in lung tumors cells. 相似文献
19.
Pasdeloup T Caron F Soyer S Castel O Aubenneau C Fauchere JL Robert R 《Pathologie-biologie》2000,48(6):533-540
This study was designed to assess the frequency and risk factors for colonization with MRSA and A. baumanii in the intensive care unit, and to analyse the relationship between colonization and infection with MRSA or A. baumanii. During a 24-day survey period, colonization was studied weekly with nasal, throat and digit skin swabs; nosocomial infections were routinely monitored according to CDC recommendations. Clinical data and invasive procedures were registered during a one-year non-epidemic period; 103 ICU patients hospitalized for more than 7 days were prospectively included. We investigated acquired colonization and nosocomial infection with SAMR or A. baumanii for 87 patients not colonized by SAMR or A. baumanii on admission. The colonization acquisition rate was 56% for MRSA and 27% for A. baumanii. Infection incidence (cases per 1,000 patient-days) was 6.46 for MRSA and 1.61 for A. baumanii. On univariate analysis, acquired MRSA colonization was associated with longer ICU stays, longer mechanical ventilation and longer central venous catheterization. Multivariate analysis only showed an association with longer ICU stay. Acquired A. baumanii colonization was associated with SAPSII, longer mechanical ventilation, and longer central venous catheterization in univariate analysis. Multivariate analysis only showed an association with SAPSII and longer mechanical ventilation. In this study, SAMR or A. baumanii infections were not associated with colonization or clinical setting or invasive procedures. 相似文献
20.
A. Decoster F. Darcy A. Caron D. Vinatier D. Houze De L''''Aulnoit G. Vittu G. Niel F. Heyer B. Lecolier M. Delcroix J. C. Monnier M. Duhamel A. Capron 《Clinical and experimental immunology》1992,87(2):310-315
This study extends a previous study and confirms that the detection of anti-P30 IgA antibodies is very helpful in the diagnosis of acute acquired or congenital toxoplasmosis. Moreover, we demonstrate that an anti-P30 IgA response can be mounted in the fetuses infected by Toxoplasma gondii during their intra-uterine life as early as week 23 of gestation. A double-sandwich ELISA described in our previous work was used to detect anti-P30 IgA antibodies in 1378 human serum samples collected from 551 patients, including 162 fetuses whose mothers had been infected by T. gondii during pregnancy, 46 congenitally infected and 90 uninfected newborns and 253 women suspected of having been infected during pregnancy, including the mothers of fetuses and newborns previously described. Anti-P30 IgA antibodies were detected in all cases of acute toxoplasmosis but in no case of chronic toxoplasmosis: in the majority of cases, the IgA antibody titre fell below cut-off in 3-9 months. Among the 46 congenitally infected newborns, anti-P30 IgA antibodies were detected in sera of 41 infected newborns (38 at birth, two in the first months of life, one in the seventh month of life), while anti-P30 IgM antibodies were detected in only 30 cases at birth and in one case during the first month of life. Among 162 fetuses, anti-P30 IgA response was observed in five infected fetuses, but was not detected in either 152 uninfected fetuses or in five fetuses considered as infected. The absence or presence of anti-P30 IgA antibodies in the fetus is discussed in relation to the date of maternal infection and collection of the fetal blood. It clearly appears from our study that the combined testing of both IgM and IgA in the fetus and the newborn is essential for a more efficient diagnosis of infection. 相似文献