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11.
Said B Iskandar Mathew G Mathai Ryland P Byrd Thomas M Roy 《The Journal of asthma》2004,41(3):337-342
Asthma affects 5%-10% of adults in the United States. Older adults (> 65 years) with asthma have higher rates of fatal asthma than younger adults. The occurrence of a respiratory emergency, such as status asthmaticus, would seem likely to create a situation of cardiopulmonary dysfunction conducive to myocardial ischemia. However, multiple studies of fatal or near-fatal asthma have failed to incriminate myocardial infarction as a contributing factor. We report a patient without underlying coronary artery disease who sustained myocardial injury consistent with myocardial ischemia and infarction during status asthmaticus while receiving recommended treatment without intravenous sympathomimetics or theophylline. 相似文献
12.
It is feared by many doctors that teaching basic life support (BLS) to high risk cardiac patients or a member of the family increases their anxiety. We trained a group of patients with recurrent ventricular tachycardia in BLS together with a friend or family member. Measurement of anxiety before and three months after training demonstrated a reduction in anxiety in both groups. This suggests that basic life support training can be targeted to high risk groups without fear of increasing anxiety. 相似文献
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The hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2) by rat sciatic nerve cytosolic phosphoinositidase C [phosphoinositide-specific phospholipase C (PIC)] was studied at neutral pH and at ionic concentrations that approximate intracellular conditions. The principal water-soluble product formed was shown to be inositol trisphosphate by anion exchange chromatography. The maximum hydrolysis rate (2.5 nmol/min/mg protein) was achieved at less than 100 nM Ca2+. Hydrolysis was markedly increased to 15 nmol/min/mg protein by inclusion of K+ in the reaction mixture. In the presence of 200 mM K+, the optimum Ca2+ was increased to approximately 600 nM. Higher Ca2+ concentrations progressively inhibited PIP2 hydrolysis. Mg2+ also inhibited the reaction, but the presence of equimolar amounts of ATP and Mg2+ had no effect. Appreciable degradation of phosphatidylinositol-4-phosphate (PIP) also occurred in the nanomolar Ca2+ range, whereas breakdown of phosphatidylinositol (PI) required millimolar Ca2+. The presence of PIP but not PI inhibited PIP2 hydrolysis. Upon subcellular fractionation of nerve, more than 50% of recovered PIC activity was in the cytosol and about 20% was located in a myelin-enriched fraction. Using PIP2 as substrate, PIC activities in nerves from normal and streptozotocin-induced diabetic animals were not different. However, the myelin-associated enzyme from diabetic animals was more labile to freezing and thawing. 相似文献
16.
In the absence of clinically positive regional nodes, any value of prophylactic dissection in malignant melanomas depends on accurate preoperative determination of the pathway of lymphatic drainage. We report on the use of noninvasive radionuclide lymphoscintigraphy in the determination of regional patterns of lymph node drainage in patients with melanomas. Ten patients were studied; treatment was altered by test results in 2. Eleven node groups were excised in 7 patients. There have been no metastatic melanomas found in any nodal basins not detected by lymphoscintigraphy 23 to 42 months after operation. 相似文献
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Santosh Isaac Poonnoose Raju P Manjooran John Mathew Pranatartiharan Ramachandran 《Journal of clinical neuroscience》2007,14(3):281-283
We report an unusual case of chronic subdural haematoma (CSH) associated with cerebrospinal fluid (CSF) rhinorrhoea emphasizing the importance of managing both conditions simultaneously. A 59- year-old man presented with watery discharge from the right nostril, of 2 months duration. MRI of the brain showed a CSH in the left fronto-parietal region with significant mass effect. There was an arachnoidocoele with a defect in the planum sphenoidale. He first underwent a burr hole evacuation of the CSH following which the CSF rhinorrhea did not subside, even with bed rest. Transnasal endoscopic closure of the CSF dural fistula was done. On the first post-operative day, he was disoriented and a CT scan showed a recollection of the subdural haematoma that required repeat evacuation. The patient was asymptomatic at discharge. To our knowledge this is the first reported case of CSF rhinorrhoea associated with CSH. Simultaneous closure of the CSF dural fistula at the time of evacuation of a coexisting CSH would be the optimal management. 相似文献
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Comparison of the Amplicor HIV-1 monitor test and the nucleic acid sequence-based amplification assay for quantitation of human immunodeficiency virus RNA in plasma, serum, and plasma subjected to freeze-thaw cycles. 总被引:6,自引:5,他引:1 下载免费PDF全文
B P Griffith M O Rigsby R B Garner M M Gordon T M Chacko 《Journal of clinical microbiology》1997,35(12):3288-3291
The Amplicor HIV-1 Monitor test was compared to the nucleic acid sequence-based amplification (Nasba) assay system for the quantitation of human immunodeficiency virus (HIV) RNA in three different types of clinical samples: plasma, serum, and plasma subjected to freeze-and-thaw cycles. Each assay detected HIV RNA in the same 73 (90%) of 81 samples tested, and the quantitative results obtained with the two assays were significantly correlated. Both assays detected higher RNA levels in patients with CD4+ cell counts lower than 200 cells/mm3 than in patients with CD4+ cell counts higher than 200 cells/mm3. In addition, RNA levels in plasma higher than 5 logs predicted higher numbers of clinical events than did RNA levels in plasma lower than 5 logs. Quantitation of HIV RNA in paired plasma and serum samples showed lower HIV RNA content in serum than in the paired plasma sample, with mean differences between HIV RNA contents of plasma and serum of 0.54 and 0.28 log RNA copy/ml by the Nasba assay and the Amplicor HIV-1 Monitor assay, respectively. No significant loss of HIV RNA was detected with either assay in plasma samples subjected to multiple freeze-and-thaw cycles. These studies demonstrate that the Nasba and Amplicor assays perform similarly with plasma and serum samples. Further, the results indicate that freeze-and-thaw cycles do not result in significant loss of detectable HIV RNA. 相似文献
20.
Chloride channel blockers inhibit myogenic tone in rat cerebral arteries 总被引:20,自引:13,他引:7
Mark T. Nelson Mathew A. Conway Harm J. Knot Joseph E. Brayden 《The Journal of physiology》1997,502(2):259-264