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排序方式: 共有1376条查询结果,搜索用时 15 毫秒
131.
STUDY OBJECTIVES: To evaluate cardiac autonomic modulation in patients with COPD during peak exercise. METHODS: Fifty-three patients with COPD (mean FEV(1), 35% predicted [SD, 11% predicted]; mean PaO(2), 68 mm Hg [SD, 11 mm Hg]; mean PaCO(2), 40 mm Hg [SD, 7 mm Hg]; mean age, 61 years [SD, 10 years]; 26 women and 27 men) and 14 healthy control subjects aged 60 years (SD, 8 years) [seven women and seven men] were studied at rest and during ramped bicycle ergometry to their volitional peak. Patients were not receiving autonomic medications other than inhaled beta-agonist agents and/or anticholinergic agents. Control subjects were not receiving any medications. Cardiac autonomic modulation was assessed via time-frequency analysis (Wigner-Ville) of ECG-derived heart rate variability as the power in the low-frequency (LF) band (ie, 0.04 to 0.15 Hz) and the high-frequency (HF) band (ie, > 0.15 to 0.4 Hz) averaged from > 3 min at rest and minutes 2 through 5 of their exercise period. RESULTS: Patients with COPD had a significantly increased mean, ln-transformed HF band from rest to peak exercise (9.9 ms(2) [SD, 1.4 ms(2)] vs 10.7 ms(2) [SD, 1.4 ms(2)], respectively; p < 0.01), while the HF band was unchanged for the control group (10.7 ms(2) [SD, 1.5 ms(2)] vs 10.4 ms(2) [1.3 ms(2)], respectively; difference not significant). The mean ln-transformed LF band was significantly increased from rest to peak exercise in patients with COPD (10.9 ms(2) [SD, 1.5 ms(2)] vs 11.5 ms(2) [SD, 1.4 ms(2)], respectively; p < 0.01) and in control subjects (10.9 ms(2) [SD, 1.5 ms(2)] vs 11.5 ms(2) [SD, 1.3 ms(2)], respectively; p < 0.01). The mean LF/HF ratio was significantly decreased from rest to peak exercise in patients with COPD (3.1 [SD, 1.5] vs 2.5 [SD, 1.0], respectively; p < 0.01) and was increased in control subjects (1.9 [SD, 0.8] vs 2.4 [1.0], respectively; p < 0.01). When expressed in normalized units ([absolute power of the components]/[total power - very low frequency power] x 100), the HF band was again significantly greater during peak exercise than at rest in the patients with COPD and was unchanged during peak exercise for the control group. Autonomic changes were not significantly correlated with age, gender, body mass index, spirometry, lung volumes, resting gas exchange, or oxygen saturation during exercise. CONCLUSION: These data suggest that, in contrast to control subjects, the balance of sympathetic to parasympathetic cardiac modulation decreases in patients with COPD during maximal volitional exercise. 相似文献
132.
Glucoregulation during and after intense exercise: effects of alpha-adrenergic blockade 总被引:3,自引:0,他引:3
Sigal RJ Fisher SJ Manzon A Morais JA Halter JB Vranic M Marliss EB 《Metabolism: clinical and experimental》2000,49(3):386-394
In intense exercise (>80% maximal oxygen consumption [VO2 max]), the 7- to 8-fold increase in glucose production (Ra) is tightly correlated with the greater than 14-fold increase in plasma norepinephrine (NE) and epinephrine (EPI). To distinguish the relative roles of alpha- and beta-adrenergic receptors, the responses of 12 control (C) lean, healthy, fit young male subjects to 87% VO2 max cycle ergometer exercise were compared with those of 7 subjects (at 83% VO2max) receiving intravenous phentolamine (Ph). The Ph group received a 70-microg/kg bolus and then 7 microg/kg/min from -30 minutes, during exercise and for 60 minutes of recovery. The data were analyzed by comparing exercise responses to exhaustion in Ph subjects (11.4 +/- 0.6 min) with those at both 12 minutes and at exhaustion in C subjects (14.6 +/- 0.3 min) and during recovery. There were no significant differences between groups in the plasma glucose response during exercise, but values were higher in C versus Ph subjects during the first 40 minutes of postexercise "recovery." The Ra response during the first 12 minutes of exercise was not different by repeated-measures ANOVA, reaching 10.6 +/- 1.3 mg/kg/min in C and 9.6 +/- 1.5 in Ph subjects at 12 minutes. However, in C subjects, Ra increased significantly to 14.1 +/- 1.2 mg/kg/min by exhaustion, and remained higher versus Ph subjects until 15 minutes of recovery. The Rd during recovery was not different between groups; thus, the higher Ra in C subjects in early recovery was responsible for the greater hyperglycemia observed in C subjects. Ph subjects showed a more rapid, marked increment (P = .002) in both plasma NE (to 64 v38 nmol/L) and EPI at exhaustion, and catecholamine concentrations remained higher in Ph versus C subjects during recovery. Whereas plasma insulin (IRI) declined in the C group, it increased 3-fold (P = .001) in the Ph group during exercise and until 15 minutes of recovery. Ph had no effect on glucagon (IRG). Thus, the glucagon to insulin ratio decreased in Ph subjects from baseline levels during exercise and early recovery, but increased in C subjects. The increase in Ra among Ph subjects despite the decrease in the glucagon to insulin ratio supports our earlier evidence that these hormones are not principal regulators of the Ra in intense exercise. The shorter time to exhaustion and markedly higher catecholamine levels in Ph subjects limited our ability to isolate the effects of alpha-adrenergic receptors on the Ra.alpha-Adrenergic receptors appear to have little influence on the Rd. 相似文献
133.
Ješe Rok Perdan-Pirkmajer Katja Hočevar Alojzija Rotar Žiga Markez Sanja Pavič-Nikolič Milena Tomšič Matija 《Clinical rheumatology》2019,38(2):273-278
Clinical Rheumatology - Epidemiological data for rheumatoid arthritis (RA) differ according to ethnicity and geographical region. Moreover, despite of clear RA management guidelines, the... 相似文献
134.
Sanja Percac-Lima MD PhD Richard W. Grant MD MPH Alexander R. Green MD MPH Jeffrey M. Ashburner MPH Gloria Gamba Sarah Oo MSW James M. Richter MD Steven J. Atlas MD MPH 《Journal of general internal medicine》2009,24(2):211-217
Background Minority racial/ethnic groups have low colorectal cancer (CRC) screening rates.
Objective To evaluate a culturally tailored intervention to increase CRC screening, primarily using colonoscopy, among low income and
non-English speaking patients.
Design Randomized controlled trial conducted from January to October of 2007.
Setting Single, urban community health center serving a low-income, ethnically diverse population.
Patients A total of 1,223 patients 52-79 years of age overdue for CRC screening, randomized to intervention (n = 409) vs. usual care
control (n = 814) groups.
Intervention Intervention patients received an introductory letter with educational material followed by phone or in-person contact by
a language-concordant “navigator.” Navigators (n = 5) were community health workers trained to identify and address patient-reported
barriers to CRC screening. Individually tailored interventions included patient education, procedure scheduling, translation
and explanation of bowel preparation, and help with transportation and insurance coverage. Rates of colorectal cancer screening
were assessed for intervention and usual care control patients.
Results Over a 9-month period, intervention patients were more likely to undergo CRC screening than control patients (27% vs. 12%
for any CRC screening, p < 0.001; 21% vs. 10% for colonoscopy completion, p < 0.001). The higher screening rate resulted in
the identification of 10.5 polyps per 100 patients in the intervention group vs. 6.8 in the control group (p = 0.04).
Limitations Patients were from one health center. Some patients may have obtained CRC screening outside our system.
Conclusions A culturally tailored, language-concordant navigator program designed to identify and overcome barriers to colorectal cancer
screening can significantly improve colonoscopy rates for low income, ethnically and linguistically diverse patients.
ClinicalTrials.gov registration number: NCT00476970 相似文献
135.
136.
Salzer U Bacchelli C Buckridge S Pan-Hammarström Q Jennings S Lougaris V Bergbreiter A Hagena T Birmelin J Plebani A Webster AD Peter HH Suez D Chapel H McLean-Tooke A Spickett GP Anover-Sombke S Ochs HD Urschel S Belohradsky BH Ugrinovic S Kumararatne DS Lawrence TC Holm AM Franco JL Schulze I Schneider P Gertz EM Schäffer AA Hammarström L Thrasher AJ Gaspar HB Grimbacher B 《Blood》2009,113(9):1967-1976
TNFRSF13B encodes transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), a B cell- specific tumor necrosis factor (TNF) receptor superfamily member. Both biallelic and monoallelic TNFRSF13B mutations were identified in patients with common variable immunodeficiency disorders. The genetic complexity and variable clinical presentation of TACI deficiency prompted us to evaluate the genetic, immunologic, and clinical condition in 50 individuals with TNFRSF13B alterations, following screening of 564 unrelated patients with hypogammaglobulinemia. We identified 13 new sequence variants. The most frequent TNFRSF13B variants (C104R and A181E; n=39; 6.9%) were also present in a heterozygous state in 2% of 675 controls. All patients with biallelic mutations had hypogammaglobulinemia and nearly all showed impaired binding to a proliferation-inducing ligand (APRIL). However, the majority (n=41; 82%) of the pa-tients carried monoallelic changes in TNFRSF13B. Presence of a heterozygous mutation was associated with antibody deficiency (P< .001, relative risk 3.6). Heterozygosity for the most common mutation, C104R, was associated with disease (P< .001, relative risk 4.2). Furthermore, heterozygosity for C104R was associated with low numbers of IgD(-)CD27(+) B cells (P= .019), benign lymphoproliferation (P< .001), and autoimmune complications (P= .001). These associations indicate that C104R heterozygosity increases the risk for common variable immunodeficiency disorders and influences clinical presentation. 相似文献
137.
We have shown that the glucagon irresponsiveness to hypoglycemia in diabetic rats is markedly improved by correction of hyperglycemia
independent of insulin. In contrast, normalization of glycemia by insulin did not improve this response. To find out whether
these glucagon responses reflect changes in islet glucagon, we directly quantified glucagon area and content in each pancreatic
islet by using fluorescent immunostaining and computerized image analysis with confocal laser scanning microscopy (CLSM).
The pancreases were analyzed in four groups of rats.
Basal plasma glucose was 7.4 ± 0.3 mM in NC, increased to 14.5±2.2 mM in DU, which was normalized in DP (5.5 ±0.5) and DI (6.7±0.8). Acute hypoglycemia (H) was induced by iv insulin injection.
The rats were sacrificed 2 h after insulin injection and the pancreas was removed. By imaging with CLSM, we quantified:
In NC, glucagon containing A cell area was 21±2% of the islet area, and glucagon intensity and concentration was 11±1 U and
36±3.0 U, respectively, in basal (O) state and did not change in (H). In DU, glucagon area increased 183%. (O) and 166% (H),
and islet glucagon intensity increased by 235% (O) (p<0.05), but decreased to 135% in H. Glucagon area in DP and DI did not differ significantly from DU. However, hypoglycemia
in DP increased glucagon intensity in islet further to 306% of normal control (p<0.05), suggesting marked increase in glucagon content indicating increased synthesis. In contrast, DI compared to DP showed
a decrease in glucagon intensity in islet (46±3, DP to 22±2 DI;p<0.05) in (H) state. Glucagon concentration followed the same pattern as its intensity. Conclusion:
This may explain, in part, unresponsiveness of glucagon to hypoglycemia often observed in insulin-dependent diabetes mellitus
(IDDM) with intensive insulin therapy. 相似文献
1. | Normal controls (NC,n=4), streptozotocin (65 mg/kg) diabetic rats. |
2. | Diabetic untreated (DU,n=4). |
3. | Diabetic Phlorizin-treated, (0.4 g/kg), twice daily for 4 d (DP,n=4). |
4. | Diabetic insulin-treated, using sustained release (2–3 U/d) insulin implant for 5 d (DI,n=4). |
1. | Percent of glucagon containing A-cell area/islet area, |
2. | Fluorescence intensity per islet area, which indicated glucagon content in the islet. |
3. | Fluorescence intensity per glucagon area indicating glucagon concentration in A-cells. |
1. | Increase in islet glucagon content in diabetic rats was associated with increase in glucagon containing A-cell area per islet. |
2. | Phlorizin-induced insulin independent correction of hyperglycemia increased glucagon content per islet in hypoglycemic state. This, in part, probably contributed to improved glucagon response to hy poglycemia observed earlier |
3. | Normalization of glycemia with insulin reduced glucagon content of each islet during hypoglycemia. |
138.
Sanja Percac-Lima Lydia E. Pace Kevin H. Nguyen Charis N. Crofton Katharine A. Normandin Sara J. Singer Meredith B. Rosenthal Alyna T. Chien 《Journal of general internal medicine》2018,33(4):415-422
Background
Rectal bleeding is a common, frequently benign problem that can also be an early sign of colorectal cancer. Diagnostic evaluation for rectal bleeding is complex, and clinical practice may deviate from available guidelines.Objective
To assess the degree to which primary care physicians document risk factors for colorectal cancer among patients with rectal bleeding and order colonoscopies when indicated, and the likelihood of physicians ordering and patients receiving recommended colonoscopies based on demographic characteristics, visit patterns, and clinical presentations.Design
Cross-sectional study using explicit chart abstraction methods.Participants
Three hundred adults, 40–80 years of age, presenting with rectal bleeding to 15 academically affiliated primary care practices between 2012 and 2016.Main Measures
1) The frequency at which colorectal cancer risk factors were documented in patients’ charts, 2) the frequency at which physicians ordered colonoscopies and patients received them, and 3) the odds of ordering and patients receiving recommended colonoscopies based on patient demographic characteristics, visit patterns, and clinical presentations.Key Results
Risk factors for colorectal cancer were documented between 9% and 66% of the time. Most patients (89%) with rectal bleeding needed a colonoscopy according to a clinical guideline. Physicians placed colonoscopy orders for 74% of these patients, and 56% completed the colonoscopy within a year (36% within 60 days). The odds of physicians ordering recommended colonoscopies were significantly higher in patients aged 50–64 years of age than in those aged 40–50 years (OR?=?2.23, 95% CI: 1.04, 4.80), and for patients whose most recent colonoscopy was 5 or more years ago (OR?=?4.04, 95% CI: 1.50, 10.83). The odds of physicians ordering and patients receiving recommended colonoscopies were significantly lower for each primary care visit unrelated to rectal bleeding (OR?=?0.85, 95% CI: 0.75, 0.96).Conclusions
Diagnostic evaluation of patients presenting to primary care with rectal bleeding may be suboptimal because of inadequate risk factor assessment and prioritization of patients’ other concurrent medical problems.139.
Rationale:Pentalogy of Cantrell (POC) is an extremely rare syndrome with an estimated incidence of 1:65,000 to 200,000 live births. Its complete form includes a midline epigastric abdominal wall defect, defects affecting the lower sternum, anterior diaphragm, diaphragmatic pericardium, and various intracardiac defects.Patient concerns:We report a case of complete POC affecting only the first-born of a set of premature dizygotic twins.Diagnosis:A giant omphalocele with an eviscerated liver and bowel on prenatal, obstetric ultrasonography at 24 gestational weeks was observed. At birth, physical examination confirmed a massive (10 × 8 cm) epigastric omphalocele in which a significant part of the liver was seen. A postnatal echocardiogram revealed the presence of an ostium secundum atrial septal defect, perimembranous ventricular septal defect, and moderate pulmonary stenosis. X-ray showed an abnormal intrathoracic positioned stomach, which was confirmed with a plain x-ray of the upper intestinal tract with hydrosoluble contrast. Computed tomography (CT) scan revealed the sternum''s absence and a close connection between the pericardial sac and the stomach wall.Interventions:The patient underwent surgical intervention at 18 days of age.Outcomes:Despite adequate and appropriate postoperative treatment, the baby rapidly deteriorated and died 72 hours after surgery.Lessons:POC is a complex, high-mortality syndrome whose management requires a multidisciplinary approach and meticulous planning. Despite all efforts, POC carries a poor prognosis, particularly in patients affected by its complete form. 相似文献
140.