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131.
G J Schuurkamp R K Kereu P K Bulungol A Kawereng W H Popon G G Crane J Greenidge P E Spicer 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1992,86(5):531-536
Bancroftian filariasis is highly endemic in the Ok Tedi region of Papua New Guinea, with a reported mean rate of 39% before the implementation of a single-dose diethylcarbamazine (DEC) treatment programme in 1986. This was followed by a 72% decline in the rate of detectable microfilaraemia and a 40% reduction in pre- and post-treatment splenomegaly. No significant difference was observed when spleen enlargement was compared to the presence of patent malaria. A significant difference in splenomegaly was observed between DEC-treated villagers and their untreated counterparts. Significant differences were reported in the rate of detectable microfilariae of Wuchereria bancrofti, but not of malaria, between the two groups. The number of DEC administrations and the period of time since the first treatment played a significant role immunologically. Significant differences were observed in immunoglobulin (Ig) M and IgG levels and in the extent of splenomegaly between DEC-treated and untreated areas. Filarial infection associated with malaria resulted in higher spleen rates and size. W. bancrofti is a major contributor to splenomegaly in the Ok Tedi region, and splenomegaly associated with bancroftian filariasis can be reduced or controlled by low, well-spaced doses of DEC. 相似文献
132.
Cause of signal loss in MR images of old hemorrhagic lesions 总被引:2,自引:0,他引:2
Old hemorrhagic lesions in the brain are characteristically surrounded by a band of hemosiderin-containing tissue. This region is typically of low signal intensity on long-echo-time (TE) radio-frequency (RF) spin-echo magnetic resonance (MR) images and on gradient-echo MR images. To determine the cause of signal loss in this band, the authors measured the signal that arises from imaging such a region with use of an RF spin-echo technique with a 180 degrees pulse incrementally displaced from TE/2. The incremental loss of signal was small. Using an agar phantom containing iron particles, the authors also showed that signal loss results primarily from diffusion in magnetic gradients. They conclude that most signal loss in the dark band surrounding areas of late-stage hemorrhage arises from diffusion in areas of magnetic inhomogeneity. 相似文献
133.
JD Carroll M Reidy PA Savundra N Cleave J McAinsh 《Cephalalgia : an international journal of headache》1990,10(2):101-105
A randomized double-blind, cross-over study using treatment periods of 12 weeks with a 2-week washout, comparing two long-acting formulations of propranolol ('Inderal' LA 160 mg daily and Half-'Inderal' LA 80 mg daily) was performed after a placebo run-in of 4 weeks on 51 patients. The study indicated that both long-acting formulations were significantly better than placebo in reducing the frequency of migraine attacks (p less than 0.01). After 12 weeks there was a significantly lower (p = 0.03) frequency of migraine attacks in patients on the higher dose formulation than in those on the lower dose formulation. There was no significant difference in the frequency of side effects produced by the two formulations. 相似文献
134.
BACKGROUND: Anecdotal evidence suggests that high-dose intravenous immunoglobulin (IVIG) is useful in the management of human immunodeficiency virus (HIV)-associated thrombocytopenia. STUDY DESIGN AND METHODS: To rigorously evaluate this therapy, a crossover study was designed to compare IVIG, given at 1 g per kg per day for 2 consecutive days each week for 4 weeks, with intravenous saline placebo administered according to the same schedule. Subjects were randomly assigned to receive either IVIG or saline during the first 4 weeks; if IVIG was given, there was a 4-week period of no therapy before beginning placebo administration. Criteria for eligibility were platelet count of less than 50,000 per microL (50 × 10(9)/L), elevated platelet-associated IgG levels, increased megakaryocytes in the bone marrow, and positive HIV antibody test. Twelve patients (11 men, 1 woman) were studied. Seven patients completed the full protocol. Four dropped out: after 2, 5 (2 patients), and 8 weeks that included at least 2 weeks of IVIG. RESULTS: All patients sustained an increase in platelet count in response to IVIG, with increments ranging from 15,000 to 358,000 per microL (15 to 350 × 10(9)/L) (mean, 180,000/microL [180 × 10(9)/L]; median, 174,000/microL [174 × 10(9)/L]). No patient had an increase after placebo infusions. There were no adverse effects of treatment, and weekly chemical analyses showed no new abnormalities except for mild elevations in the serum protein. The duration of responses ranged from 2 to 10 weeks. No patient demonstrated refractoriness to IVIG. CONCLUSION: IVIG consistently raises platelet counts in patients with HIV-associated thrombocytopenia. 相似文献
135.
M. K. Urban MD PhD K. Jules-Elysee MD C. Loughlin PA W. Kelsey BA E. Flynn BA 《HSS journal》2008,4(1):76-80
The diagnosis of a postoperative myocardial infarction (PMI) is important in the orthopedic population because these events
can be associated with significant cardiac morbidity. Plasma troponin I (cTnI) analysis has markedly increased our ability
to detect myocardial damage. Using cTnI analysis for evidence of a PMI, we prospectively assessed all of our patients for
(1) the 1-year incidence of PMI, (2) the clinical consequences of a PMI in relation to the level of the cTnI release, and
(3) 6-month follow-up for cardiac complications. During a 12-month period, patients at risk for perioperative myocardial ischemia
were assessed for a PMI by serum cTnI levels and daily serial ECGs. Patients with cTnI levels above the reference level (≥0.4 ng/ml)
were also assessed for new cardiac regional wall motion abnormalities with an echocardiogram and 6-month postdischarge adverse
cardiac events. Of the 758 patients who were assessed for a PMI, 49 patients had detectable cTnI levels (≥0.4 ng/ml); the
incidence of a PMI was 0.6% of all surgical cases and 6.5% of those patients were at risk for a cardiac event. A PMI was more
common after hip arthroplasty than other orthopedic procedures. Twenty-three patients had a cTnI level >3.0 ng/ml, and 74%
these patients (17/23) had anginal symptoms and/or ischemic ECG changes. Nine of these patients (9/23) had new postoperative
echocardiographic changes, five (5/23) required emergency transfer to a cardiac care unit, and 10 (10/23) had postoperative
cardiac complications. In contrast, 15 patients with levels of cTnI <3.0 ng/ml and without ischemic ECG changes and/or anginal
symptoms had no postoperative cardiac complications. Fourteen patients (14/47) had cardiac complications 6 months after discharge,
including four cardiac deaths, one fatal stroke, and four patients with unstable anginal episodes that required a change in
medical management, and six patients required coronary revascularization. Orthopedic surgical patients with cTnI level <3 ng/ml
and without symptoms or ECG changes suggestive of myocardial ischemia (15/49) may have different risks than those with higher-level
cTn1.
This study was funded by the Department of Anesthesiology, Hospital for Special Surgery, New York, NY. 相似文献
136.
Screening and Treatment for Subclinical Hypertensive Heart Disease in Emergency Department Patients With Uncontrolled Blood Pressure: A Cost‐effectiveness Analysis
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137.
Glucose-specific regulation of aldose reductase in capan-1 human pancreatic duct cells In vitro. 总被引:3,自引:0,他引:3
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J V Busik S R Hootman C A Greenidge D N Henry 《The Journal of clinical investigation》1997,100(7):1685-1692
Impaired pancreatic duct secretion is frequently observed in insulin-dependent diabetes mellitus (IDDM), although the cellular mechanism(s) of dysfunction remains unknown. Studies in other tissues have suggested that a hyperglycemia-induced decrease in Na, K-ATPase activity could contribute to the metabolic complications of IDDM and that increased polyol metabolism is involved in this response. The present studies examined the effects of glucose on Na, K-ATPase activity and on expression and activity of aldose reductase (AR), a primary enzyme of polyol metabolism, in Capan-1 human pancreatic duct cells. Increasing medium glucose from 5.5 to 22 mM caused a 29% decrease in Na,K-ATPase activity. The decrease was corrected by 100 microM sorbinil, a specific AR inhibitor. Increasing glucose from 5.5 to 110 mM also resulted in concentration-dependent increases in AR mRNA and enzyme activity that could be resolved into two components, one that was glucose specific and observed at pathophysiological concentrations (< 55 mM) and a second that was osmotically induced at high concentrations (> 55 mM) and which was not glucose specific. The present study demonstrates that pathophysiological levels of glucose specifically activate polyol metabolism with a consequent decrease in Na,K-ATPase activity in pancreatic duct epithelial cells, and that this response to hyperglycemia could contribute to decreased pancreatic secretion observed in IDDM. This is the first report of AR regulation in the pancreatic duct epithelium. 相似文献
138.
Loss of Local Capture of the Pulmonary Vein Myocardium After Antral Isolation: Prevalence and Clinical Significance
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139.
140.
This study was focused on the immunohistochemical profile of the adenomatoid odontogenic tumor. A Pub/Medline search revealed a number of immunohistochemical studies including cytokeratin profiles, extracellular matrix proteins, Integrins, ameloblast‐associated proteins resorption regulators (RANK, RANKL), p53, PCNA, MDM2 protein, cyclin D1, Ki‐67, Bcl‐2 metallothionein, metalloproteinases, D56 hepatocyte growth factor, c‐met, DNA methyltransferase, podoplanin, TGF‐βI, Smad‐2/3, Smad‐I‐5/‐8, Smad 4, beta‐ catenin, calretinin, and clonality. Careful interpretation of the findings indicates that the adenomatoid odontogenic tumor may be more of a hamartomatous than neoplastic nature. 相似文献