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991.
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993.
Anaemia of chronic disease (ACD) is a common finding involving iron deficiency and signs of inflammation. Here, we report on two patients with ACD where a persistent infection with Chlamydophila (Chlamydia) pneumoniae (CP) was detected in bone marrow (BM) biopsies. Infection was suspected by routine cytology and confirmed by immunofluorescence, electron microscopy, polymerase chain reaction (PCR) including different primer sets and laboratories and sequencing of the PCR product. This is a first report of chlamydial presence in the BM of anaemic patients. The cases are presented because persistent chlamydial infection may contribute more frequently to chronic refractory anaemia than previously suspected.  相似文献   
994.
BACKGROUND: Acetaminophen is the most common drug employed in deliberate self-poisoning (DSP) in many countries and can lead to acute liver failure. The purpose of the present study was to compare DSP with acetaminophen with DSP with other medications. METHODS: From January 2001 to December 2002, all patients admitted after DSP to Soroka University Hospital in Beer-Sheva, Israel, were identified. Demographic data and medical history were obtained retrospectively. RESULTS: There were 282 incidences of DSP in the study period. The mean age of 94 patients with an acetaminophen overdose was lower than that of patients who had attempted DSP with other medications (24.8 vs. 34.6 years, p<0.001). There was no gender or ethnic difference between the groups. Patients with DSP with acetaminophen were less likely to make recurrent attempts (23.4% vs. 39.9% p=0.006), less likely to have psychiatric disorders (32% vs. 59% p<0.001), and had a shorter hospital stay (1.7 vs. 2.1 days, p=0.05). The acetaminophen group had less of an impairment in level of consciousness (84% vs. 52.1% p<0.001) and had less need for ICU care (6.4% vs. 14.9%, p=0.04). Serum levels were checked in 68 (72.3%) of the patients in the acetaminophen group and they were found to be high in 6 (8.8%) of them (95% CI 2.1-15.5%). CONCLUSION: Taking an overdose of acetaminophen is a common method of DSP, with patients tending to have a more benign presentation and shorter hospital stay than those who attempt DSP with other medications. Further research on the optimal care of these patients and multi-disciplinary approaches to DSP prevention are needed.  相似文献   
995.
To further establish the role of oxidative stress in the pathogenesis of acute bronchial asthma, we investigated the effects of platelet-activating factor (PAF) challenge on systemic oxidant-antioxidant balance in 12 asthmatic patients (age, 25+/-3[SEM] yr; FEV1, 95+/-10% predicted), using a double blinded, controlled with Lyso-PAF (L-PAF), cross-over design. Respiratory system resistance (Rrs), arterial blood gases, peripheral blood neutrophils and oxidant-antioxidant balance, including thiobarbituric acid (TBA)-malondialdehyde (MDA) adducts, protein sulphydryls and Trolox equivalent antioxidant capacity (TEAC), were assessed at baseline and 5, 15 and 45 min after PAF and L-PAF (18 microg each) bronchoprovocation. Urinary leukotriene E4 (uLTE4) elimination was measured 120 min after challenge. Compared with baseline, as expected, PAF increased significantly Rrs and AaPO2 and decreased PaO2 and peripheral blood neutrophils along with a rebound neutrophilia and increased uLTE4. By contrast, markers of systemic oxidative stress remained unaltered throughout the study. Unlike PAF, L-PAF-induced changes were negligible. We conclude that there is no systemic oxidant-antioxidant imbalance during acute bronchoconstriction induced by PAF in these patients with mild asthma.  相似文献   
996.
We tested 32 Candida isolates recovered in the early 1990s from the bloodstreams of patients with candidemia for in vitro susceptibility to fluconazole and determined if MIC and/or the daily dose of fluconazole/MIC ratio correlated with the response to therapy. This is a unique data set since 87.5% (28/32) of patients were treated with fluconazole doses now considered to be inadequate (/= 64 mug/ml) isolates were 67% (14/21), 20% (1/5), and 0% (0/6), respectively. A dose/MIC ratio >50 was associated with a success rate of 74% (14/19), compared to 8% (1/13) for a dose/MIC ratio 相似文献   
997.
BACKGROUND: Sublingual nitroglycerin is advocated to sensitize the passive 70 degrees head-upright tilt test (HUTT) of patients with unexplained syncope. We hypothesized that a detailed analysis of hemodynamic responses recorded during a negative HUTT could predict the outcome to a subsequent nitroglycerin sensitized HUTT (NTG-HUTT). METHODS: Thirty-two patients (46 +/- 3 years, 17 males) with recurrent unexplained syncope but a negative HUTT were included. Heart rate, arterial blood pressure, and central hemodynamics assessed by transthoracic impedance (preejection and rapid left ventricular ejection time, slow ejection time, peak amplitude of first derivative, and cardiac index) were recorded during supine rest and 45 minutes HUTT. Changes from supine rest of the variables were retrospectively compared between patients with a negative (n = 15, NTG-HUTT(-)) and positive (n = 17, NTG-HUTT(+)) outcome to 10 minutes subsequent NTG-HUTT. RESULT: Significant differences between groups were observed during the 15th-20th minutes (Italian protocol) and during the last 5 minutes of passive HUTT (Westminster protocol). The combination of cutoff values, determined by receiver operating curves, on hemodynamic variables changes during the last 5 minutes predicted the outcome to a NTG-HUTT with a sensitivity of 76% and a specificity of 87%. The cutoff values determined during 15th-20th minutes gave an attractive sensitivity (85%) but a too weak specificity (53%) to shorten the 45 minutes passive HUTT at 20 minutes. CONCLUSION: Outcome to a NTG-HUTT can be reliably predicted by selected criteria determined from multiple hemodynamic variables recorded during a passive 70 degrees HUTT.  相似文献   
998.
999.
Epizootics of encephalitis in El Salvador killed 203 equines between November 2001 and April 2003. During an investigation of the outbreaks, 18 (25%) of 73 serum samples collected from stablemates of deceased animals in 2003 had antibodies to West Nile virus. Ten of these infections were confirmed by plaque reduction neutralization tests, suggesting West Nile virus has extended its range and spread to Central America.  相似文献   
1000.
Cheng CM  Tseng V  Wang J  Wang D  Matyakhina L  Bondy CA 《Endocrinology》2005,146(12):5086-5091
IGF action has been implicated in the promotion of oxidative stress and aging in invertebrate and murine models. However, some in vitro models suggest that IGF-I specifically prevents neuronal oxidative damage. To investigate whether IGF-I promotes or retards brain aging, we evaluated signs of oxidative stress and neuropathological aging in brains from 400-d-old Igf1-/- and wild-type (WT) mice. Lipofuscin pigment accumulation reflects oxidative stress and aging, but we found no difference in lipofuscin deposition in Igf1-/- and WT brains. Likewise, there was no apparent difference in accumulation of nitrotyrosine residues in Igf1-/- and WT brains, except for layer IV/V of the cerebral cortex, where these proteins were about 20% higher in the Igf1-/- brain (P = 0.03). We found no difference in the levels of oxidative stress-related enzymes, neuronal nitric oxide synthase, inducible nitric oxide synthase, and superoxide dismutase in Igf1-/- and WT brains. Tau is a microtubule-associated protein that causes the formation of neurofibrillary tangles and senile plaques as it becomes hyperphosphorylated in the aging brain. Tau phosphorylation was dramatically increased on two specific residues, Ser-396 and Ser-202, both glycogen synthase kinases target sites implicated in neurodegeneration. These observations indicate that IGF-I has a major role in regulating tau phosphorylation in the aging brain, whereas its role in promoting or preventing oxidative stress remains uncertain.  相似文献   
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