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排序方式: 共有1457条查询结果,搜索用时 15 毫秒
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Yuqin Ye MD PhD Keren Wang MD PhD Fang Deng MD PhD Yingqi Xing MD PhD 《Muscle & nerve》2013,47(1):68-71
Introduction: The dystrophic features in hindlimb skeletal muscles of female mdx mice are unclear. Methods: We analyzed force‐generating capacity and force decline after lengthening contraction‐induced damage (fragility). Results: Young (6‐month‐old) female mdx mice displayed reduced force‐generating capacity (?18%) and higher fragility (23% force decline) compared with female age‐matched wild‐type mice. These 2 dystrophic features were less accentuated in young female than in young male mdx mice (?32% and 42% force drop). With advancing age, force‐generating capacity decreased and fragility increased in old (20 month) female mdx mice (?21% and 57% force decline), but they were unchanged in old male mdx mice. Moreover, estradiol treatment had no effect in old female mdx mice. Conclusions: Female gender–related factors mitigate dystrophic features in young but not old mdx mice. Further studies are warranted to identify the beneficial gender‐related factor in dystrophic muscle. Muscle Nerve, 2013 相似文献
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Konigstein Maayan Biner Simon Topilsky Yan Abramowitz Yigal Havakuk Ofer Ben-Assa Eyal Leshem-Rubinow Eran Arbel Yaron Keren Gad Banai Shmuel Finkelstein Ariel 《Journal of Echocardiography》2014,12(1):17-23
Background
Aortic stenosis is associated with concentric left ventricle (LV) hypertrophy or remodeling resulting in impaired diastolic function and elevated left-sided filling pressure. We investigated the changes in LV geometry and LV filling hemodynamics, giving emphasis to parameters associated with changes in diastolic function after transcatheter aortic valve implantation (TAVI).Methods
Comprehensive diastolic assessment was performed before and six months after TAVI in 70 patients with severe aortic stenosis. Patients with any degree of mitral stenosis or >mild left-sided valvular regurgitation were excluded.Results
In the entire cohort six months after TAVI, LV end-diastolic diameter increased (44.1 ± 6 versus 45 ± 6 mm, P = 0.02), whereas LV mass and relative wall thickness (RWT) decreased (270.1 ± 76 versus 245.1 ± 75 g and 0.53 ± 0.15 versus 0.46 ± 0.1, respectively; P < 0.0001 for both). Lateral e′ increased (5.8 ± 2 versus 6.6 ± 3 cm/s, P = 0.03) and left atrium (LA) volume, E/e′ ratio, and systolic pulmonary pressure decreased (88.1 ± 30 versus 80 ± 28 cc, 18 ± 7.8 versus 16.3 ± 5.5, and 42.7 ± 14.9 versus 38.7 ± 12 mmHg, respectively; P < 0.05 for all), suggesting reduction in LA pressure. The improvement in LA volume and E/e′ was almost exclusively seen in patients with LV hypertrophy before TAVI (P < 0.05 both), as opposed to patients with concentric remodeling.Conclusions
In our preliminary study, TAVI resulted in LV and LA reverse remodeling, and improved LV relaxation and LA filling pressure in patients with severe aortic stenosis and concentric hypertrophy. Patients with concentric remodeling at baseline seem to have limited improvement in LV diastolic function and filling pressure following TAVI, but larger clinical trials would be required to conclude if they have no improvement at all. 相似文献45.
The aim of the current study was to evaluate the influence of hydrofluoric (HF) acid concentration and conditioning time on the shear bond strength (SBS) of dual cure resin cement to pressed lithium disilicate ceramic compared to treatment with an Etch and Prime self-etching glass-ceramic primer (EP). A total of 100 samples of pressed lithium disilicate (IPS e.max Press, Ivoclar Vivadent) were randomly divided into five groups (n = 20) according to surface treatment: two different concentrations of HF (5% or 9%), for different durations (20 or 90 s), or treatment with EP. Adhesion of light-cured resin cement to the treated surface was tested by the SBS test. The substrate surfaces of the specimen after failures were examined by SEM. Data were analyzed using Weibull distribution. The highest cumulative failure probability of 63.2% of the shear bond strength (η parameter) values was in the 9% HF −90 s group (17.71 MPa), while the lowest values were observed in the 5% HF −20 s group (7.94 MPa). SBS values were not affected significantly by the conditioning time (20 s or 90 s). However, compared to treatment with 5% HF, surface treatment with 9% HF showed a significantly higher η (MPa) as well as β (reliability parameter). Moreover, while compared to 9% HF for 20 s, EP treatment did not differ significantly in SBS values. Examination of the failure mode revealed a mixed mode of failure in all the groups. Within the limits of this study, it is possible to assume that IPS e.max Press surface treatment with 9% HF acid for only 20 s will provide a better bonding strength with resin cement than using 5% HF acid. 相似文献
46.
The hemodynamic and clinical effects of parenteral and oral CI-930, a new phosphodiesterase type III inhibitor with combined vasodilator and inotropic properties, were studied in 12 patients with severe congestive heart failure refractory to therapy including captopril. The maximum response to dobutamine was also determined. Intravenous CI-930 increased cardiac index from 1.73 +/- 0.48 to 2.38 +/- 0.55 L/min/m2, and reduced pulmonary capillary wedge pressure from 19.2 +/- 7.9 to 12.5 +/- 6.4 mm Hg, mean right atrial pressure from 7.5 +/- 6.3 to 3.6 +/- 4.0 mm Hg, and systemic vascular resistance from 2288 +/- 860 to 1711 +/- 611 dynes . sec . cm-5 (p less than 0.001 for all). Heart rate and mean systemic arterial pressure were unchanged. The increment in cardiac index produced by dobutamine was higher than for CI-930, 2.68 +/- 0.55 vs 2.38 +/- 0.55 L/min/m2, p less than 0.001. However, reduction in pulmonary capillary wedge pressure tended to be less with dobutamine, 15.7 +/- 7.9 vs 12.5 +/- 6.4 mm Hg (NS). Hemodynamic benefits of oral CI-930 were equivalent to that of the parenteral drug. Duration of action was 9 to 12 hours. Chronic therapy resulted in subjective improvement in approximately 50% of patients. Exercise capacity, assessed by maximum oxygen consumption, was unchanged, 8.4 +/- 3.3 vs 9.8 +/- 3.4 ml/kg/min (NS). No overt laboratory manifestations of toxicity were observed. 相似文献
47.
Edy Stermer Alexandra Lavy Tova Rainis Omer Goldstein Dean Keren Abdel-Rauf Zeina 《Journal canadien de gastroenterologie》2008,22(9):758-760
BACKGROUND: The clinical significance of colorectal wall thickening (CRWT) in patients undergoing abdominal computed tomography (CT) has not yet been definitively established. OBJECTIVES: To compare alleged findings on abdominal CT with those of a follow-up colonoscopy. METHODS: Ninety-four consecutive patients found to have large-bowel abnormalities on abdominal CT were referred for colonoscopy. Of these patients, 48 were referred for a suspected colorectal tumour and 46 for CRWT. Colonoscopy was performed and findings were compared. RESULTS: Of the 48 suspected colorectal tumours, 34 were determined to be neoplastic lesions on colonoscopy. Of these, 26 were malignant and eight were benign. Colonoscopy revealed no abnormality in 30 of 46 patients with CRWT as a solitary finding, and revealed some abnormality in 16 patients (12 had diverticular disease, four had benign neoplastic lesions). CONCLUSIONS: CRWT as an incidental and solitary finding on CT should not be regarded as a pathology prompting a colonoscopy. Approximately two-thirds of the patients had a normal colonoscopy and the remaining patients had benign lesions (12 had diverticular disease and four had benign neoplastic lesions). However, many of these patients seem to warrant colonoscopy regardless of CT findings, particularly patients who have a family history of colorectal cancer, have positive fecal occult blood test results or who are older than 50 years of age. 相似文献
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Yaron Arbel Amir Sternfeld Adiel Barak Zvia Burgansky-Eliash Amir Halkin Shlomo Berliner Itzhak Herz Gad Keren Ardon Rubinstein Shmuel Banai Ariel Finkelstein 《Atherosclerosis》2014
Background
The “Slow Coronary Flow” (SCF) phenomenon in the presence of angiographically normal coronaries is attributed to microvascular and endothelial dysfunction. The microcirculation can be non-invasively assessed by measuring retinal blood flow velocity.The aim of the present study was to evaluate the efficacy of the “Retinal Functional Imager” (RFI) device as a noninvasive method of diagnosing patients with slow coronary flow.Methods
Coronary blood flow velocity assessed by corrected TIMI Frame Count and retinal arterioles blood flow assessed by RFI were measured in 28 consecutive patients with normal coronary arteries. The patients were divided into 2 groups: a slow coronary flow (SCF) and a normal coronary flow (NCF) groups.Results
Inverse correlation was found between retinal and coronary blood flows so that higher retinal arterial flow velocity was observed in the SCF group (3.8 ± 1.1 mm/s vs. 2.9 ± 0.61 mm/s, respectively, p = 0.022). RFI provided 73% sensitivity and 77% specificity for diagnosing SCF using ROC analysis. Additionally, patients with SCF had higher values of serum LDL cholesterol (104.7 ± 18.93 mg/dl vs. 81.55 ± 14.62 mg/dl in NCF, p = 0.005), Glucose (96.9 ± 23.0 mg/dl vs. 83.55 ± 9.7 mg/dl in NCF, p = 0.024), and lower percentage of statin consumption (40.0% vs. 76.9% in NCF, p = 0.049).Conclusions
Slow coronary blood flow can be non-invasively diagnosed with Retinal Functional Imager. Patients with normal coronary arteries and slow coronary blood flow have high retinal arteriolar blood flow. Early non-invasive diagnosis of SCF might help detect individuals who are at higher risk to develop coronary atherosclerosis, and to provide them with early preventive measures. 相似文献50.