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991.
Incidence of ARDS in an adult population of northeast Ohio   总被引:5,自引:0,他引:5  
STUDY OBJECTIVES: To assess the incidence of the ARDS in a well-defined adult population. DESIGN: Kaiser Permanente of northeast Ohio, a health maintenance organization, uses the Cleveland Clinic Foundation as its only tertiary care center. In an ongoing prospective assessment in the Cleveland Clinic ICUs, we identified adult Kaiser Permanente patients with ARDS between 1996 and 1999. ARDS was defined according to the 1994 American-European Consensus Conference criteria. The denominator in the incidence calculation was the adult members of Kaiser Permanente of each year of the study period, and the numerator was the new adult ARDS patients in this particular year. The cause of ARDS, the mortality, and the cause of death were retrospectively identified, as well as other characteristics of the study population. RESULTS: ARDS was diagnosed in 66 patients during the 3-year study period. The incidence per 100,000 population was 11.4 in 1996, 19.8 in 1997, and 14.4 in 1998; the overall incidence was 15.3/100,000/yr. The mean PaO(2)/fraction of inspired oxygen (+/- SD) was 110.8 +/- 37.8, the mean APACHE II was 23.4 +/- 6.9, and the mean ICU stay was 12.0 +/- 9.5 days. The most common cause of ARDS was direct lung injury (75.8%), and the most common cause of death was septic shock (53.8%). CONCLUSION: The incidence of ARDS in an adult population in northeast Ohio was 15.3/100,000/yr, a number that is slightly higher but comparable to recent estimates reported by other researchers.  相似文献   
992.
We assessed the relation between baseline electrocardiographic ischemia grades and initial myocardial area at risk (AR) and final infarct size (IS) in 49 patients who had undergone (99m)Tc sestamibi single-photon emission computed tomography before and 6 +/- 1 days after thrombolysis. Patients were classed as having grade III ischemia (ST segment elevation with terminal QRS distortion, n = 19) or grade II ischemia (ST elevation but no terminal QRS distortion, n = 30). We compared AR and IS by baseline ischemia grade and treatment (adenosine vs. placebo) and assessed relations of infarction index (IS/AR ratio x100) to time to thrombolysis, baseline ischemia grade, and adenosine therapy. Time to thrombolysis was similar for grade II and grade III. For placebo- treated patients, the median AR did not differ significantly between grade II (38%) and grade III patients (46%, p = 0.47), nor did median IS (16 vs. 40%, p = 0.096), but the median infarction index was 66 vs. 90% (p = 0.006). For adenosine-treated patients, median AR (21 vs. 26%, p = 0.44), median IS (5 vs. 17%, p = 0.15), and their ratio (31 vs. 67%, p = 0.23) did not differ significantly between grade II and grade III patients. The infarction index independently related to grade III ischemia (p = 0.0121) and adenosine therapy (p = 0.045). Infarct size related to baseline ischemia grade and was reduced by adenosine treatment. Necrosis progressed slowlier with baseline grade II versus III ischemia, which could offer more time for myocardial salvage with reperfusion.  相似文献   
993.
994.
PURPOSE: Aim of this study has been to evaluate natural killer (NK) activity in patients with colorectal tumors before and after curative surgery. METHODS: Forty colorectal cancer patients without distant metastases were stratified according to American Joint Committee on Cancer/International Union Against Cancer staging system into three categories: Stage I (n = 12), Stage II (n = 15), and Stage III (n = 13). All of them underwent curative resection, and there were no major postoperative complications. Venous blood samples were obtained preoperatively, at surgical wound closure, and on the 1st, 7th, and 21st postoperative days. Mononuclear cells were isolated over Ficoll-Hypaque ? (Lymphoprep, Nycomed Pharma AS, Oslo, Norway) gradients, and NK activity was assayed by evaluation of cytotoxic response against K562 cells. Normal NK activity was achieved from 15 healthy donors. Percentage relative increments in relation to preoperative levels were calculated for every postoperative sample, and t- test was used for statistical evaluation. RESULTS: Before surgery, Stages II and III patients had lower levels of NK activity than healthy people (P < 0.05 and P < 0.001, respectively). NK activity always fell after surgery (Stage I: -18.48±11.42; Stage II: ?16.93±13.57; Stage III: ?35.29±12.03, at day 1 postsurgery) and appeared to rise slightly by the 21st postoperative day in Stage I patients (+4.87±12.41). Stage II, and especially Stage III, patients did show a significant recovery by the 21st postoperative day (+23.63±9.36 and +43.19±13.34, respectively). At this time, NK activity in these two groups was not significantly lower than in normal subjects (P > 0.05). CONCLUSION: NK activity is depressed in colorectal cancer patients in relation to progression of illness, even at locoregional stages. Curative resection of tumors at Stages II and III has promoted a recovery of NK activity in patients with uneventful postoperative courses.  相似文献   
995.
Trends of asthma in Mexico: an 11-year analysis in a nationwide institution   总被引:5,自引:0,他引:5  
Vargas MH  Díaz-Mejía GS  Furuya ME  Salas J  Lugo A 《Chest》2004,125(6):1993-1997
STUDY OBJECTIVES: Asthma prevalence is increasing in many countries. Some recent articles, however, claim that this tendency is ending. Our aim was to investigate asthma trends in Mexico. DESIGN: Annual data on health services provided to asthmatic patients were retrospectively analyzed from 1991 to 2001. SETTING: The Instituto Mexicano del Seguro Social, the largest nationwide medical institution in Mexico (approximately 24 to 32 million insured subjects). PARTICIPANTS: Health services provided to subjects of any age. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Asthma-associated health services, either expressed as absolute number or as rate per insured subjects, progressively increased until 1997 in family physician office visits (FPOVs) [newly diagnosed cases only], emergency department visits (ERVs), and hospital discharges (HDs). From that year onward, the number and rates of asthma-associated health services decreased. The same trends were observed for age groups 0 to 4 years, 5 to 14 years, 15 to 44 years, and 45 to 64 years. Using a different approach, asthma was diagnosed each year in approximately 0.4% of all FPOVs, but a decrease in this percentage was observed from 1997 onward. Likewise, asthma caused increasing percentages of all ERVs and HDs until 1997, followed by a sharp decline thereafter. CONCLUSIONS: A decline in absolute and relative numbers of asthma-associated health services occurred over recent years in all medical settings, suggesting that the epidemic of new asthma cases is ending and/or that better control of the disease has been achieved.  相似文献   
996.
OBJECTIVE: Disorders of the mitochondrial electron transport chain enzymes of oxidative phosphorylation (OXPHOS) have neurologic, musculoskeletal, ophthalmologic, cardiac, and GI manifestations. Many adult and pediatric patients with disorders of OXPHOS have abnormalities in intestinal motility. The purpose of this study was to describe pediatric patients who initially presented with signs of GI dysmotility and were later evaluated and found to have a disorder of OXPHOS. METHODS: Data were collected on six patients, including initial GI and neurologic symptoms, histology of skeletal muscle biopsies, mitochondrial DNA mutational analysis, OXPHOS enzyme assay, upper GI barium imaging, technetium-99M liquid gastric emptying scan, upper GI endoscopy, esophageal manometry, and antroduodenal manometry. RESULTS: All six children presented with symptoms of GI dysmotility within 2 wk of life. Patients later developed symptoms of neurologic disorders. All patients had abnormalities in OXPHOS enzyme analysis. Muscle histology showed nonspecific changes with no ragged red fibers. Sequencing of the mitochondrial DNA showed no recognized mutations. No patient had any evidence of intestinal obstruction or malrotation by upper GI barium imaging. Four patients had delayed gastric emptying. Three patients had endoscopic and histologic evidence of esophagitis. All six had demonstrable neuropathic abnormalities by antroduodenal manometry, including the following: nonpropagated antral bursts, absent migrating motor complexes, postprandial antral hypomotility, retrograde migrating motor complexes, and tonic contractions with the migrating motor complex. CONCLUSIONS: Abnormalities in GI motility may be an early presenting sign of disorders of OXPHOS in children.  相似文献   
997.
The frequency of Entamoeba histolytica and Entamoeba dispar infection was analyzed in a rural community in the state of Morelos, Mexico, using polymerase chain reaction (PCR). Sociodemographic variables as risk factors for the infection were assessed. Results highlighted the number of individuals with intestinal parasites (43.1%) in the community, indicating extensive fecalism. A high frequency of E. histolytica asymptomatic infection, higher than E. dispar infection (13.8% versus 9.6%), was detected by PCR. Anti-amebic antibody levels (IgG) in serum and saliva (IgA) samples were not associated with E. histolytica intestinal infection. These findings suggest a predominant distribution of E. histolytica strains of low invasive potential in this community.  相似文献   
998.
INTRODUCTION AND OBJECTIVES: Previous prognostic studies of Chagas' disease have focused on mortality associated with end-stage cardiopathy (i.e., heart failure). Our aim was to identify indicators of progression in early-stage Chagas' heart disease. MATERIAL AND METHOD: The study included 856 patients with 3 positive anti-Trypanosoma cruzi test results. Those with heart failure were excluded. Patients were divided into 3 clinical groups: those without heart disease (Group I); those with heart disease but without left ventricular enlargement (Group II); and those with left ventricular enlargement but without heart failure (Group III). The endpoint was progression to a more severe clinical stage or death due to cardiovascular disease. A Cox regression model was used to derive a clinical risk score from clinical, electrocardiographic and echocardiographic variables. RESULTS: At study entry, the patients' mean age was 43.7 years. They were followed up for a mean of 8 years. The following were predictors of heart disease progression: age at entry (HR=1.05; 95% CI, 1.02-1.07; P<.001), left ventricular systolic diameter (HR=1.06; 95% CI, 1.04-1.09; P<.001), intraventricular conduction abnormalities (HR=1.85; 95% CI, 1.02-3.36; P=.04), and sustained ventricular tachycardia (HR=3.97; 95% CI, 1.65-9.58; P=.002). Treatment with benznidazole reduced the risk of progression (HR=0.40; 95% CI, 0.23-0.72; P=.002). The devised clinical risk score was effective in stratifying the likelihood of cardiopathy progression. CONCLUSIONS: Specific clinical indicators and a derived clinical risk score can be used to predict the progression of chronic chagasic myocarditis in patients without heart failure.  相似文献   
999.
OBJECTIVE: The apolipoprotein AI-CIII-AIV cluster has been associated with the response to a urate-lowering diet, and polymorphisms in the apolipoprotein CIII gene have been associated with hyperuricemia and hypertriglyceridemia. We assessed the influence of polymorphisms in the apolipoprotein AI-CIII-AIV cluster on the response to a urate-lowering diet in patients with hyperuricemia. METHODS: A urate-lowering diet was followed for 2 weeks by 64 men with hyperuricemia. Plasma concentrations of triglycerides, cholesterol, glucose, and uric acid, and the uric acid clearance and 24-hour uric acid urinary excretory fraction were measured before and after the diet. The data were analyzed in association with the polymorphisms of the apolipoprotein AI-CIII-AIV gene cluster. RESULTS: After the urate-lowering diet, the plasma levels of triglycerides, cholesterol, glucose, and uric acid and 24-hour uric acid excretion all fell significantly. Paired sample ANOVA showed that the decrease was mainly due to the diet, except for the plasma triglycerides, which were influenced by allele X2 of the XmnI polymorphism of the apolipoprotein AI gene. CONCLUSION: The response of the biological variables to a urate-lowering diet was mainly influenced by diet. Changes in triglycerides were also influenced by the apolipoprotein AI XmnI polymorphism (p = 0.04), suggesting a gene-diet interaction (p = 0.03).  相似文献   
1000.
OBJECTIVES: Helicobacter pylori causes gastric adenocarcinoma. We assessed the success of H. pylori eradication therapy in a medically underserved population in Chiapas, Mexico, that is at high risk for gastric cancer risk. METHODS: Healthy volunteers with both antibodies to CagA and gastrin levels > or = 25 ng/ml were randomly assigned to receive either a combination of omeprazole, amoxicillin, and clarithromycin or matched placebo for 1 wk. Endoscopy with seven biopsies was performed at baseline, at 6 wk, and 1 yr after treatment. Treatment success was defined as loss of H. pylori by histological analysis. Cure was assessed using change in serology based on the standardized absorbance of a H. pylori ELISA. RESULTS: H. pylori eradication rates were high (intent-to-treat analysis: 76.3% [95% CI = 68.7-84.0%] after 6 wk and 76.1% [95% CI = 67.7-84.6%] after 1 yr; per protocol analysis: 77.8% [95% CI = 70.1-85.4%] after 6 wk and 75.2% [95% CI = 66.5-84.0%] after 1 yr). Nine subjects on active treatment and one subject on placebo who were without H. pylori at 6 wk were infected at 1 yr (recurrence rates 10.7% and 33.3%, respectively, p = 0.31). Median changes in standardized absorbance at 1 yr were 47% and 1% for successfully and unsuccessfully treated patients, respectively. A 10% decline in standardized absorbance after 1 yr had 84% sensitivity and 100% specificity for H. pylori eradication. CONCLUSIONS: Even with a short course of treatment against H. pylori, a high rate of eradication rate can be achieved in populations at high risk for stomach cancer. Serum antibodies are useful in assessing efficacy of therapy.  相似文献   
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