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81.
A commercial IgM immunoblot kit was evaluated for dengue diagnosis with a panel of serum specimens collected from patients in a dengue endemic area. The kit is not recommended for use in its present form because of its undesirable rate of false-positive results. However, by substituting internal controls with the reference positive and negative controls that are more representative of those seen in endemic areas and by modifying the positive and negative scoring criteria, sensitivity and specificity of 80.3% and 94.5%, respectively, were obtained. These results are comparable with those obtained with the IgM ELISA on specimens, most of which were obtained from outpatient health care facilities. With further technical modifications, inclusion of a visual guide to ensure scoring standardization, and a more complete elaboration of the limitations of the test, wide application of the kit in diagnostic laboratories should be possible. 相似文献
82.
GI Frolenkov F Kalinec GA Tavartkiladze B Kachar 《Canadian Metallurgical Quarterly》1997,73(3):1665-1672
We have used a high-resolution motion analysis system to reinvestigate shape changes in isolated guinea pig cochlear outer hair cells (OHCs) evoked by low-frequency (2-3 Hz) external electric stimulation. This phenomenon of electromotility is presumed to result from voltage-dependent structural changes in the lateral plasma membrane of the OHC. In addition to well-known longitudinal movements, OHCs were found to display bending movements when the alternating external electric field gradients were oriented perpendicular to the cylindrical cell body. The peak-to-peak amplitude of the bending movement was found to be as large as 0.7 microm. The specific sulfhydryl reagents, p-chloromercuriphenylsulfonic acid and p-hydroxymercuriphenylsulfonic acid, that suppress electrically evoked longitudinal OHCs movements, also inhibit the bending movements, indicating that these two movements share the same underlying mechanism. The OHC bending is likely to result from an electrical charge separation that produces depolarization of the lateral plasma membrane on one side of the cell and hyperpolarization on the other side. In the cochlea, OHC bending could produce radial distortions in the sensory epithelium and influence the micromechanics of the organ of Corti. 相似文献
83.
Indomethacin is a very effective tocolytic agent. However, concern about its possible constrictive effect on fetal ductus arteriosus has limited the use of this medication in pregnancy. A 29-year-old woman was treated with indomethacin at 27 weeks of gestation for preterm labor and polyhydramnios. She received a dose of 75 mg/day for 5 weeks. At 35 weeks of gestation, she had a cesarean delivery due to fetal distress, and a hydropic baby was delivered. The infant died shortly after. Nonimmune hydrops fetalis and closed ductus arteriosus were the only pathological findings at autopsy. In utero, irreversible, complete closure of the ductus arteriosus is very rare. In the case presented, prolonged use of indomethacin during pregnancy was associated with complete closure of the ductus arteriosus that developed most probably after discontinuation of therapy. This case emphasizes the need for frequent fetal echocardiography examinations during as well as after maternal indomethacin treatment. 相似文献
84.
Subopitmal glycemic control in hospitalized patients with type 2 (non-insulin-dependent) diabetes mellitus can have adverse consequences, including increased neurologic ischemia, delayed wound healing and an increased infection rate. Poor glycemic control can also affect the outcome of the primary illness. If possible, hospitalized diabetic patients should continue their previous antihyperglycemic treatment regimen. Decreased physical activity and the stress of illness often lead to hyperglycemia in hospitalized patients with type 2 diabetes. When indicated, insulin is given either as a supplement to usual therapy or as a temporary substitute. The overall benefit of the traditional sliding-scale insulin regimen has been questioned. Insulin supplementation given according to an algorithm may be a logical alternative. Any antihyperglycemic regimen should be administered and monitored in a manner coincident with the intake of food or other sources of calories. Factors that can alter glycemic control acutely, including specific medical conditions and medications, should be identified and anticipated. 相似文献
85.
86.
KW Mahaffey CB Granger CA Toth HD White AL Stebbins GI Barbash A Vahanian EJ Topol RM Califf 《Canadian Metallurgical Quarterly》1997,30(7):1606-1610
OBJECTIVES: This study sought to evaluate the incidence of ocular hemorrhage in patients with and without diabetes after thrombolytic therapy for acute myocardial infarction. BACKGROUND: Ocular hemorrhage after thrombolysis has been reported rarely. However, there is concern that the risk is increased in patients with diabetes. In fact, diabetic hemorrhagic retinopathy has been identified as a contraindication to thrombolytic therapy without clear evidence that these patients have an increased risk for ocular hemorrhage. METHODS: We identified all suspected ocular hemorrhages from bleeding complications reported in patients enrolled in the Global Utilization of Streptokinase and t-PA for Occluded Coronary Arteries (GUSTO)-I trial. Additional information was collected on a one-page data form. We compared the incidence and location of ocular hemorrhages in patients with and without diabetes. RESULTS: There were 40,899 patients (99.7%) with information about diabetic history and ocular bleeding. Twelve patients (0.03%) had an ocular hemorrhage. Intraocular hemorrhage was confirmed in only one patient. There were 6,011 patients (15%) with diabetes, of whom only 1 had an ocular hemorrhage (eyelid hematoma after a documented fall). The upper 95% confidence intervals for the incidence of intraocular hemorrhage in patients with and without diabetes were 0.05% and 0.006%, respectively. CONCLUSIONS: Ocular hemorrhage and, more important, intraocular hemorrhage after thrombolytic therapy for acute myocardial infarction is extremely uncommon. The calculated upper 95% confidence interval for the incidence of intraocular hemorrhage in patients with diabetes was only 0.05%. We conclude that diabetic retinopathy should not be considered a contraindication to thrombolysis in patients with an acute myocardial infarction. 相似文献
87.
K Yasuda R Espinosa EM Davis MM Le Beau GI Bell 《Canadian Metallurgical Quarterly》1993,17(3):785-786
The gene encoding the somatostatin receptor subtype designated as SSTR5 was mapped to human chromosome 20p11.2 by using fluorescence in situ hybridization to metaphase chromosomes. Fluorescence in situ hybridization using a probe for SSTR5 in combination with probes for neuroendocrine convertase-2 (NEC2), thrombomodulin (THBD), and brain glycogen phosphorylase (PYGB) established a physical order for these loci of 20pter-NEC2-SSTR5-THBD-PYGB-cen. 相似文献
88.
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90.
We studied the actions of intoxicating doses of ethanol on excitatory inputs from the basolateral nucleus of the amygdala, a major afferent system projecting to the nucleus accumbens (NAcc). In view of the hypothesized role of opioid receptors on the effects of ethanol on NAcc physiology, we also explored whether naloxone modulates ethanol-induced suppression of NAcc excitability in halothane anesthetized and freely moving unanesthetized rats. Intraperitoneal administration of ethanol (1.2-1.4 g/kg) markedly suppressed a subgroup of amygdala-activated NAcc neurons. The ethanol-induced reduction in amygdala-activated NAcc neurons was not reversed by naloxone (5.0 mg/kg, intraperitoneally). Moreover, naloxone had no effect on the suppressive effects of ethanol on NAcc spontaneous activity in either halothane-anesthetized or unanesthetized freely moving preparations. These findings suggest that opiate mechanisms either are not participating or are not solely responsible for the inhibitory effects of acute intoxicating doses of ethanol on NAcc physiology. 相似文献