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61.
Beriberi, thiamine deficiency, is classified as "dry" (neurologic) or "wet" (cardiovascular) and may be mixed. Deficiency of this vitamin may be nutritional or secondary to alcohol intoxication. In Western societies (occidental beriberi), the disorder is more commonly observed in long-term alcohol abusers. However, it may go undiagnosed because it is relatively uncommon. In some cases (acute cardiovascular beriberi), early treatment with parenteral vitamin B1 is required to prevent the development of low-output state and sudden death. We report a case of occidental beriberi with fatal outcome despite therapy.  相似文献   
62.
Endometriosis of the sigmoid colon is a pathologic entity which is infrequently reported. A 29-year-old woman was admitted to the hospital because of abdominal pain, constipation, and menstrual rectal bleeding. Endometriosis was suspected, and CT (virtual) colonoscopy showed severe stenosis of the orthosigmoid canal due to a submucosal mass. Sigmoidoscopy using a pediatric endoscope was successful, and biopsies confirmed the original diagnosis. Non-invasive techniques such as endoscopic ultrasound and CT (virtual) colonoscopy now make it possible to diagnose sigmoid endometriosis. The latter technique, in particular, is feasible and well tolerated.  相似文献   
63.
The cardiac myofilament protein troponin I (cTnI) is phosphorylated by protein kinase C (PKC), a family of serine/threonine kinases activated within heart muscle by a variety of agonists. cTnI is also a substrate for cAMP-dependent protein kinase (PKA) activated during beta-adrenergic signaling. To investigate the role of cTnI phosphorylation in contractile regulation by these pathways, we generated transgenic mice harboring a mutated cTnI protein lacking phosphorylation sites for PKC (serine(43/45) and threonine(144) mutated to alanine) and for PKA (serine(23/24) mutated to alanine). Transgenic mice were interbred with cTnI-knockout mice to ensure the absence of endogenous phosphorylatable cTnI. Here, we report that regulation of myocyte twitch kinetics by beta-stimulation and by endothelin-1 was altered in myocytes containing mutant cTnI. In wild-type myocytes, the beta-agonist isoproterenol decreased twitch duration and relaxation time constant (tau) by 37% to 44%. These lusitropic effects of isoproterenol were reduced by about half in nonphosphorylatable cTnI mutant myocytes and were absent in cTnI mutants also lacking phospholamban (generated by crossing cTnI mutants with phospholamban-knockout mice). These observations are consistent with important roles for both cTnI and phospholamban phosphorylation in accelerating relaxation after beta-adrenergic stimulation. In contrast, endothelin-1 increased twitch duration by 32% and increased tau by 58%. These endothelin-1 effects were substantially blunted in nonphosphorylatable cTnI myocytes, indicating that PKC phosphorylation of cTnI slows cardiac relaxation and increases twitch duration. We propose that beta-agonists and endothelin-1 regulate cardiac twitch dynamics in opposite directions in part through phosphorylation of the myofilament protein cTnI on distinct sites.  相似文献   
64.
65.
Although numerous studies have documented outbreaks of carbapenem-resistant Klebsiella pneumoniae (CRKP) possessing various carbapenemases, reports on outbreaks due to CRKP possessing extended-spectrum β-lactamases (ESBLs) and/or AmpCs with porin lesions have been limited. Here, we describe an outbreak caused by an ertapenem-resistant, CTX-M-15-producing clonal K. pneumoniae strain expressing an OmpK36 porin variant. From May 2012 to November 2012, 37 ertapenem-resistant K. pneumoniae isolates phenotypically negative for carbapenemase production were recovered from 19 patients hospitalized in the intensive care unit of a Greek hospital. The isolates were either susceptible or intermediate to other carbapenems and resistant to all remaining β-lactams but cefotetan. Phenotypic and molecular analysis revealed the presence in all isolates of the blaCTX-M-15 gene on a conjugative 100-kb plasmid, disruption in the expression of the ompK35 gene, and the production of an Ompk36 porin variant. The index case was a patient admitted from another hospital. Active surveillance upon admission and on a weekly basis was immediately initiated; environmental samples were also periodically tested. Molecular typing showed that all clinical isolates as well as two ertapenem-resistant environmental K. pneumoniae isolates belonged to the same clonal type and were assigned to multilocus sequence typing (MLST) sequence type 101 (ST101). As all colonized/infected patients were hospitalized during overlapping periods, cross-infection was considered the main route for the dissemination of the outbreak strain. Despite reinforcement of infection control measures and active surveillance, the outbreak lasted approximately 7 months. Identification of hidden carriers upon admission and by screening on a weekly basis was found valuable for early recognition and subsequent successful management of the outbreak.  相似文献   
66.
Sj?gren's syndrome in progressive systemic sclerosis   总被引:1,自引:0,他引:1  
Forty-four sequential, unselected patients with progressive systemic sclerosis (PSS) were prospectively evaluated for evidence of coexistent Sj?gren's syndrome (SS). This diagnosis was established when a patient with focal lymphocytic infiltration in the labial salivary gland (LSG) biopsy, scoring greater than or equal to 2+ in Tarpley's scale, had keratoconjunctivitis sicca (KCS) (positive rose bengal test) and/or xerostomia (subjective xerostomia and decreased parotid flow rate). Ten patients had an LSG biopsy score of greater than or equal to 2+, 3 a 1+ score, 17 had mild to moderate fibrosis only and 14 had normal tissue. Nine of the 10 patients with a greater than or equal to 2+ score had SS, according to applied criteria, suggesting a 20.5% prevalence of SS in our population with PSS. On the other hand, pure fibrosis in the biopsy was felt to be secondary to PSS. Parotid gland enlargement was present in 44.4% of the patients with SS, but was extremely uncommon in the fibrosis and normal tissue groups. Subjective xerophthalmia and xerostomia, although elicited by specific questionnaire in the majority of the patients with SS, did not constitute major complaints. Serious internal manifestations, with the exception of esophageal and pulmonary involvement, were unusual in all groups. Anti-Ro (SSA) antibodies were detected in 33.3% of the patients with SS and 11.8% of those with fibrosis. Our study suggests that SS in scleroderma is relatively common and, although lacking prominent exocrine gland symptomatology, resembles primary SS in some clinical and serologic respects.  相似文献   
67.
The aim of the current study was to investigate the contribution of various strategies to increase influenza vaccine uptake among health care workers (HCWs) working in hospitals in Greece during the 2005-2006 season. A total of 132 Greek public hospitals participated in the study. The mean HCWs vaccination rate against influenza during 2005-2006 was 16.36% compared with 1.72% during the previous season. Logistic regression analysis showed that the implementation of the following strategies was significantly associated with influenza vaccination rates above the mean vaccination rate: a mobile vaccination team (OR 2.942, 95% CI 1.154-5.382, p-value 0.016) and lectures on influenza and influenza vaccine (OR 2.386, 95% CI 0.999-5.704, p-value 0.036). In conclusion, in Greece influenza vaccination rates among HCWs remain low; however, the implementation of specific strategies was associated with increased vaccine uptakes.  相似文献   
68.
Classic congenital adrenal hyperplasia (CAH) is associated with impaired function of the adrenal cortex and medulla leading to decreased production of cortisol and epinephrine. As a result, the normal exercise-induced rise in blood glucose is markedly blunted in such individuals. We examined whether an extra dose of hydrocortisone, similar to that given during other forms of physical stress such as intercurrent illness, would normalize blood glucose levels during exercise in patients with CAH. We studied hormonal, metabolic, and cardiorespiratory parameters in response to a standardized high-intensity exercise protocol in nine adolescent patients with classic CAH. Patients were assigned to receive either an additional morning dose of hydrocortisone or placebo, in addition to their usual glucocorticoid and mineralocorticoid replacement in a randomized, double-blind, crossover design 1 h before exercising. Although plasma cortisol levels approximately doubled after administration of the additional hydrocortisone dose compared with the usual single dose, fasting and exercise-induced blood glucose levels did not differ. In addition, no differences were observed in the serum concentrations of the glucose-modulating hormones epinephrine, insulin, glucagon, and GH and of the metabolic parameters lactate and free fatty acids. Although maximal heart rate was slightly higher after stress dosing (193 +/- 3 vs. 191 +/- 3 beats/min, mean +/- sem, P < 0.05), this did not affect exercise performance or perceived exertion. We conclude that patients with classic CAH do not benefit from additional hydrocortisone during short-term, high-intensity exercise. Although this has not been tested with long-term exercise, a high degree of caution should be used when considering the frequent use of additional hydrocortisone administration with exercise, given the adverse side effects of glucocorticoid excess.  相似文献   
69.
Background: Capecitabine and oxaliplatin are both effective and well-tolerated monotherapies for the treatment of advanced colorectal cancer (CRC). Oxaliplatin has also been shown to be very effective when combined with 5-FU/LV in the first-line setting. Aim of the Study: Assess the efficacy and safety of capecitabine plus oxaliplatin (XELOX) in patients with previously untreated advanced CRC. Methods: Fifty-three patients with measurable disease received capecitabine 1,000 mg/m2 twice daily on d 1–14 and oxaliplatin 130 mg/m2 on d 1, every 3 wk. Of these, 52 were evaluable for safety and 49 for antitumor response. Results: There was a low rate of grade 1/2 adverse events; grade 3/4 events included leukopenia (10%), neutropenia (6%), thrombocytopenia (2%), nausea/vomiting (4%), and diarrhea (4%). The overall response rate was 39% (95% CI, 25–54%) and median time to disease progression was 7.8 mo. Conclusions: XELOX is an active and well-tolerated first-line treatment for advanced CRC. Randomized phase III studies are ongoing to compare XELOX with FOLFOX in view of the comparable efficacy and safety but superior convenience of XELOX therapy. Presented in part at the 39th American Society of Clinical Oncology Annual Meeting, Chicago, IL, May 31–June 3, 2003.  相似文献   
70.
OBJECTIVES: The aim of this study was to evaluate the serum lipid profile and to assess the prevalence of hepatic steatosis in adult beta-thalassaemic patients with chronic hepatitis C virus (HCV) infection. METHODS: Thirty-five adult HCV infected, multi-transfused, beta-thalassaemia patients (beta-HCV patients), 63 otherwise normal patients with chronic HCV infection (HCV patients) and 54 beta-thalassaemia patients without chronic viral hepatitis (beta patients) were studied. Total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides, viral markers and liver histology were evaluated. RESULTS: Serum total cholesterol, HDL-C and LDL-C were found at significantly lower levels in beta-HCV and beta patients than in HCV patients. Triglyceride levels were significantly lower in the HCV group compared with the beta group. Nine (25.7%) of the 35 beta-HCV patients had mild hepatic steatosis. Thirteen (23.6%) of 55 HCV patients presented mild and 4/55 (7.3%) moderate hepatic steatosis. None of the beta group presented steatosis. When we compared beta-HCV and HCV patients with steatosis, we found that beta-HCV patients had a lower degree of steatosis (11.1+/-7% vs 22.9+/-17.2%, P=0.021). Multivariate logistic regression analysis showed that the only independent predictor associated with hepatic steatosis in beta-HCV and HCV patients was genotype 3a (OR, 3.61; 95% CI, 1.22-10.71, P=0.021). CONCLUSIONS: Adult beta-thalassaemia patients, compared to other patients with chronic HCV infection, present lower cholesterol levels (total cholesterol, HDL, LDL) and similar frequency but a lower degree of hepatic steatosis. This difference in the degree of steatosis is most likely due to the higher prevalence of genotype 3a in the non-beta-thalassaemia group.  相似文献   
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