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991.
The effects of tributylin chloride (TBT) on vascular smooth muscle responses to norepinephrine, nitroprusside (SNP) and atrial natriuretic peptide (ANP) were studied in isolated aortic rings of rats. TBT did not interfere with norepinephrine-induced contraction or SNP-induced vasorelaxation. However, TBT produced a dose-dependent inhibition of ANP-induced vasorelaxation. Inhibition was not observed with inorganic tin chloride, SnCl2. The inhibition of vasorelaxation was accompanied by a parallel inhibition of ANP-induced cGMP generation. SNP-induced generation of cGMP was not affected by TBT. TBT did not interfere with binding of ANP to its receptor in bovine adrenal glands suggesting that the effects of TBT were mediated by direct interaction with membrane-bound guanylate cyclase. 相似文献
992.
993.
William E Trick Wendy W Chapman Mary F Wisniewski Brian J Peterson Steven L Solomon Robert A Weinstein 《Infection control and hospital epidemiology》2003,24(12):950-954
OBJECTIVE: To evaluate whether a natural language processing system, SymText, was comparable to human interpretation of chest radiograph reports for identifying the mention of a central venous catheter (CVC), and whether use of SymText could detect patients who had a CVC. DESIGN: To identify patients who had a CVC, we performed two surveys of hospitalized patients. Then, we obtained available reports from 104 patients who had a CVC during one of two cross-sectional surveys (ie, case-patients) and 104 randomly selected patients who did not have a CVC (ie, control-patients). SETTING: A 600-bed public teaching hospital. RESULTS: Chest radiograph reports were available from 124 of the 208 participants. Compared with human interpretation, SymText had a sensitivity of 95.8% and a specificity of 98.7%. The use of SymText to identify case- and control-patients resulted in a sensitivity of 43% and a specificity of 98%. Successful application of SymText varied significantly by venous insertion site (eg, a sensitivity of 78% for subclavian and a sensitivity of 3.7% for femoral). Twenty-six percent of the case-patients had a femoral CVC. CONCLUSIONS: Compared with human interpretation, SymText performed well in interpreting whether a report mentioned a CVC. In patient populations with less frequent CVC placement in femoral veins, the sensitivity for CVC detection likely would be higher. Applying a natural language processing system to chest radiograph reports may be a useful adjunct to other data sources to automate detection of patients who had a CVC. 相似文献
994.
Pirfenidone prevents the progression of irreversible glomerular sclerotic lesions in rats 总被引:1,自引:0,他引:1
Fujio SHIMIZU Masafumi FUKAGAWA Shitotomo YAMAUCHI Masayoshi TANIYAMA Sadao KOMEMUSHI Solomon B MARGOLIN Kiyoshi KUROKAWA 《Nephrology (Carlton, Vic.)》1997,3(5):315-322
Summary: Pirfenidone (PFD) is a new drug which has been shown to prevent or even reverse the extracellular matrix accumulation in several organs. to examine the effect of PFD on the progressive glomerulosclerosis, we treated model rats with irreversible chronic renal disease per orally with 500 mg/kg bodyweight of PFD per day. the model rats were made by intravenous injection of anti-Thy-1 monoclonal antibody 1-22-3 at 1 h following unilateral nephrectomy, which results in chronic progressive glomerulosclerosis. Twenty-four hours later, 32 female Wistar rats were divided into two groups and were fed standard chow with (PFD group: P) or without PFD (control group: C). All rats were sacrificed on day 42. No significant difference in the bodyweight or the amount of chow intake was observed between the two groups. the remnant kidney was significantly ( P <0.05) heavier in C (2.11 ± 0.15 g) than in P (1.70 ± 0.13 g). This finding, together with light microscopic findings, showed that PFD administration resulted in the prevention of renal hypertrophy. On day 42, proteinuria in P (124.3 ± 31.9 mg/day) was significantly lower than in C (214.6 ± 8.1 mg/day), and P maintained significantly better renal function than C as judged by serum urea nitrogen and creatinine levels. Mean matrix score was less in P (178 ± 17) than in C (225 ± 22). Crescent formation was observed in 17% of glomeruli in P and in 35% in C. Tubulointerstitial lesions were also less severe in P. Furthermore, inflammation and sclerosis indices detected by immunohistochemistry (e.g. ED-1, OX8, TGF-beta α-smooth muscle actin, collagen type I, were less in P). These data suggest that PFD may be a promising agent for the prevention of progressive and irreversible glomerulosclerosis. 相似文献
995.
OBJECTIVE: The aim of the current study was to systematically assess the psychological effects of the Persian Gulf War on a nonclinical group of elderly Israeli civilians with and without a Holocaust background. METHOD: Sixty-one elderly Holocaust survivors and 131 elderly civilians without a Holocaust background completed questionnaires in their homes. Measures included sense of safety, symptoms of psychological distress, and levels of state and trait anxiety. RESULTS: Findings indicate that Holocaust survivors perceived higher levels of danger and reported more symptoms of acute distress than comparison subjects. In addition, they displayed higher levels of both state and trait anxiety. CONCLUSIONS: Findings do not support the notion that prior experience with extreme stress has an inoculating effect that leads to greater resilience in dealing with other forms of stress. On the contrary, Holocaust experience was found to render the elderly more vulnerable rather than less. These findings of greater vulnerability among Holocaust survivors are of particular significance since they stem from a nonclinical group. 相似文献
996.
Barbara I Braun Stephen B Kritchevsky Edward S Wong Steve L Solomon Lynn Steele Cheryl L Richards Bryan P Simmons 《Infection control and hospital epidemiology》2003,24(12):926-935
OBJECTIVES: To describe the conceptual framework and methodology of the Evaluation of Processes and Indicators in Infection Control (EPIC) study and present results of CVC insertion characteristics and organizational practices for preventing BSIs. The goal of the EPIC study was to evaluate relationships among processes of care, organizational characteristics, and the outcome of BSI. DESIGN: This was a multicenter prospective observational study of variation in hospital practices related to preventing CVC-associated BSIs. Process of care information (eg, barrier use during insertions and experience of the inserting practitioner) was collected for a random sample of approximately 5 CVC insertions per month per hospital during November 1998 to December 1999. Organization demographic and practice information (eg, surveillance activities and staff and ICU nurse staffing levels) was also collected. SETTING: Medical, surgical, or medical-surgical ICUs from 55 hospitals (41 U.S. and 14 international sites). PARTICIPANTS: Process information was obtained for 3,320 CVC insertions with an average of 58.2 (+/- 16.1) insertions per hospital. Fifty-four hospitals provided policy and practice information. RESULTS: Staff spent an average of 13 hours per week in study ICU surveillance. Most patients received nontunneled, multiple lumen CVCs, of which fewer than 25% were coated with antimicrobial material. Regarding barriers, most clinicians wore masks (81.5%) and gowns (76.8%); 58.1% used large drapes. Few hospitals (18.1%) used an intravenous team to manage ICU CVCs. CONCLUSIONS: Substantial variation exists in CVC insertion practice and BSI prevention activities. Understanding which practices have the greatest impact on BSI rates can help hospitals better target improvement interventions. 相似文献
997.
Identification of a mouse brain cDNA that encodes a protein related to the Alzheimer disease-associated amyloid beta protein precursor.
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W Wasco K Bupp M Magendantz J F Gusella R E Tanzi F Solomon 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(22):10758-10762
We have isolated a cDNA from a mouse brain library that encodes a protein whose predicted amino acid sequence is 42% identical and 64% similar to that of the amyloid beta protein precursor (APP). This 653-amino acid protein, which we have termed the amyloid precursor-like protein (APLP), appears to be similar to APP in overall structure as well as amino acid sequence. The amino acid homologies are concentrated within three distinct regions of the two proteins where the identities are 47%, 54%, and 56%. The APLP cDNA hybridizes to two messages of approximately 2.4 and 1.6 kilobases that are present in mouse brain and neuroblastoma cells. Polyclonal antibodies raised against a peptide derived from the C terminus of APLP stain the cytoplasm in a pattern reminiscent of Golgi staining. In addition to APP, APLP also displays significant homology to the Drosophila APP-like protein APPL and a rat testes APP-like protein. These data indicate that the APP gene is a member of a strongly conserved gene family. Studies aimed at determining the functions of the proteins encoded by this gene family should provide valuable clues to their potential role in Alzheimer disease neuropathology. 相似文献
998.
999.
EEG Abnormalities in Children with a First Unprovoked Seizure 总被引:4,自引:4,他引:0
Shlomo Shinnar† Harriet Kang† Anne T. Berg§ Eli S. Goldensohn W. Allen Hauser Solomon L. Mosh醇 《Epilepsia》1994,35(3):471-476
Summary: We examined EEG findings from an ongoing study of 347 children with a first unprovoked seizure. EEGs were available in 321 (93%), and 135 (42%) had an abnormal EEG. EEG abnormalities included focal spikes (n = 77), generalized spike and wave discharges (n = 28), slowing (n = 43), and nonspecific abnormalities (n = 7). Abnormal EEGs were more common in children with remote symptomatic seizures (60%) than in those with idiopathic seizures (38%) (p < 0.003), more common in partial seizures (56%) than in generalized seizures (35%) (p < 0.001), and more common in children age >3 years (52%) than in younger children (12%) (p < 0.001). Records including both awake and sleep tracings were available in 148 (46%) cases. For 122 (38%) only awake tracings and for 51 (16%) only sleep tracings were available. Fifty-nine (40%) of the 148 patients with both an awake and asleep tracing had abnormal EEGs. Of 50 such EEGs with epileptiform abnormalities, 15 (30%) demonstrated the abnormality either only while awake (n = 8) or only while asleep (n = 7). Of 17 patients with EEG slowing, 8 showed slowing only in the awake tracing and 9 showed slowing in both the awake and asleep tracing. Children with even a single unprovoked seizure have a high incidence of EEG abnormalities. Obtaining a combined awake and sleep EEG significantly increases the yield of EEG abnormalities. In children with an idiopathic first seizure, EEG abnormalities are associated with an increased risk of seizure recurrence. 相似文献
1000.
D Gall C Roussel I Susa E D'Angelo P Rossi B Bearzatto MC Galas D Blum S Schurmans SN Schiffmann 《The Journal of neuroscience》2003,23(28):9320-9327
Calcium-binding proteins such as calretinin are abundantly expressed in distinctive patterns in the CNS, but their physiological function remains poorly understood. Calretinin is expressed in cerebellar granule cells, which provide the major excitatory input to Purkinje cells through parallel fibers. Calretinin-deficient mice exhibit dramatic alterations in motor coordination and Purkinje cell firing recorded in vivo through unknown mechanisms. In the present study, we used patch-clamp recording techniques in acute slice preparation to investigate the effect of a null mutation of the calretinin gene on the intrinsic electroresponsiveness of cerebellar granule cells at a mature developmental stage. Calretinin-deficient granule cells exhibit faster action potentials and generate repetitive spike discharge showing an enhanced frequency increase with injected currents. These alterations disappear when 0.15 mm of the exogenous fast-calcium buffer BAPTA is infused in the cytosol to restore the calcium-buffering capacity. A proposed mathematical model demonstrates that the observed alterations of granule cell excitability can be explained by a decreased cytosolic calcium-buffering capacity resulting from the absence of calretinin. This result suggests that calcium-binding proteins modulate intrinsic neuronal excitability and may therefore play a role in information processing in the CNS. 相似文献