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Population studies indicate that astigmatism decreases from the corneal center toward the periphery. A standard toric intraocular lens (IOL) with a constant cylinder power cannot correct uniformly across this gradient. We built an astigmatic eye model based on corneal topography data. A progressive-toric lens with gradually decreasing cylinder power was compared with an identically designed lens but featuring conventional astigmatism correction. Residual astigmatism did not differ significantly (P=0.06) at 3 mm, and the Strehl ratio was identical for both lenses (0.51 ±0.15, P=0.88). At 5 mm, the progressive IOL yielded significantly lower residual astigmatism by 0.10 D (P<0.001). The Strehl ratio was 0.30 ±0.08 with the progressive and 0.29 ±0.08 with the standard lens (P<0.001). At 3 mm, the optical performance was comparable for both IOLs. However, at 5 mm, the progressive-toric was more effective in correcting astigmatism, and it yielded reduced residual astigmatism compared to a standard toric lens.  相似文献   
64.
Vascularized lymph node transfer (VLNT) is a promising microvascular free flap technique for the surgical treatment of lymphedema. To date, few experimental animal models for VLNT have been described and the viability of lymph nodes after the transfer tested. We aimed to evaluate the feasibility of axillary VLNT in the rat. Lymph node containing flaps were harvested from the axillary region in 10 Lewis rats based on the axillary vessels. Flaps were transferred to the ipsilateral groin and end‐to‐side microanastomosis was performed to the femoral vessels using 10‐0 sutures. Indocyanine green (ICG) angiography was used to confirm flap perfusion. On postoperative day 7, flaps were elevated to assess their structure and vessel patency. Hematoxylin and eosin staining was used to confirm the presence and survival of lymph nodes. All animals tolerated the procedure well. Immediate post‐procedure ICG angiography confirmed flap perfusion. No signs of ischemia or necrosis were observed in donor extremities. At postoperative day 7, all flaps remained viable with patent vascular pedicles. Gross examination and histology confirmed the presence of 3.6 ± 0.5 lymph nodes in each flap without any signs of necrosis. This study showed that the transfer of axillary lymph nodes based on the axillary vessels is feasible. The flap can be used without the need for donor animals and it contains a consistent number of lymph nodes. This reliable VLNT can be further utilized in studies involving lymphedema, transplantation, and induction of immunologic tolerance. © 2015 Wiley Periodicals, Inc. Microsurgery 35:662–667, 2015.  相似文献   
65.
Wozakowska-Kapłon B  Opolski G  Janion M  Kosior D 《Kardiologia polska》2004,61(12):513-21; discussion 522
BACKGROUND: Plasma concentration of atrial natriuretic peptide (ANP) is elevated in patients with atrial fibrillation (AF) and in patients with chronic heart failure (CHF).Aim. To assess ANP level in patients with permanent AF and advanced CHF. METHODS: The study group consisted of 41 patients (27 males, mean age 62+/-8 years) with AF of a mean duration of 8.8 months. Twenty six (63%) patients were in NYHA class II, and 15 (37%) - in NYHA class III or IV. All patients underwent clinical and echocardiographic evaluation as well as ANP plasma concentration assessment. Multiple regression analysis was used to identify factors which determine ANP plasma concentration. RESULTS: Mean ANP plasma concentration was 52.4+/-22.7 pg/ml in the whole study group; 38.6+/-10.8 pg/ml in NYHA class II patients and 74.9+/-18.7 pg/ml in NYHA class III-IV subjects (p<0.0001). Among echocardiographic parameters, patients with NYHA class III or IV had significantly lower left ventricular ejection fraction and greater left atrial volume than patients with NYHA class II (32% versus 56%, p<0.0001 and 101.0+/-23.8 cm(3) versus 83.4+/-16.1 cm(3), p<0.006, respectively). Multiple regression analysis revealed a significant negative correlation between AF duration and ANP level (p=0.0013) in a group of patients with NYHA class III or IV and identified AF duration as an independent predictor of ANP plasma concentration in this group of patients. CONCLUSIONS: ANP plasma concentration in patients with persistent AF and advanced CHF is determined by AF duration - the longer the AF duration the lower the ANP level.  相似文献   
66.
Last decade brought great development in the treatment of patients with heart failure (HF). General use of angiotensin-converting-enzyme inhibitors (ACE-I) in patients with asymptomatic left ventricular dysfunction or with HF significantly reduced morbidity and mortality. The aim of this study was to assess how the specialists from Cardiology Department and Gastroenterology Department think that heart failure should be managed, how they implement their knowledge and if it is consistent with the recommendation of European Society of Cardiology (ESC) and whether differences exists in practice between specialists. In the first phase the specialists, cardiologists and diabetologists, answered the questions about the management of different stages of HF. In second phase we analysed medical documentation of 345 patients aged between 38 and 98 years, hospitalised in Cardiology and Gastroenterology Departments from October 2000 to February 2002 by reason of coronary artery disease, hypertension and dilated cardiomyopathy. In the third phase we compared the knowledge of heart failure management from questionnaire and its implementation, the compliance with ESC recommendation and finally whether differences in clinical practice exist between cardiologist and diabetologists. RESULTS: ACE-I were prescribed in all NYHA classes of HF. In over 50% patients in II NYHA class to 94% in IV NYHA class in Cardiology Department. Differences between the Departments in prescribing of ACE-I were observed. Beta-blockers (BB) were used with the same frequency in all NYHA classes, more often in Cardiology Department. Frequency of the administration of digoxin, diuretics, aldosterone receptor blocker was increasing starting with II NYHA class. The highest compliance between declarations from questionnaire and clinical practice concerned the use of BB and ACE-I combination.  相似文献   
67.
Bochowicz A  Styczyński G  Szulc M  Gurba H  Pruszczyk P 《Kardiologia polska》2002,57(12):564-6; discussion 567
A case of a 37-year-old male admitted to the hospital due to dyspnea and chest pain is presented. Electrocardiogram showed negative T waves in V1 and V2 as well as subtle ST segment elevation in all precordial leads. Cardiac enzymes were moderately elevated. The initial diagnosis was myocarditis or acute coronary syndrome, however, transthoracic echocardiography showed a marked right ventricular overload which suggested acute pulmonary embolism. The latter diagnosis was confirmed by transesophageal echocardiography which revealed thrombosis of both left and right pulmonary arteries. The patient received thrombolysis and anticoagulants, and his condition improved. He was discharged home and the course of a six-month follow-up was uneventful.  相似文献   
68.
The aim of this study was to investigate somatic properties and physiological capacity, and analyze kinematic parameters in the 200 m breaststroke swimming race. Twenty-seven male swimmers participated in the study. They were 15.7±1.98 years old. Their average height was 1.80 ± 0.02 m and lean body mass (LBM) was 62.45 ± 8.29 kg. Physiological exercise capacity was measured in two separate 90 sec. all-out tests, one for the arms and second for legs. During the tests total work of arm cranking (TWAR) and cycling (TWLG) as well as peak of VO2 for arm (VO2peakAR) and leg (VO2peakLG) were measured. The underwater swimmers body movements were recorded during the all-out swimming 200m breaststroke speed test using an underwater camera installed on a portable trolley. The swimming kinematic parameters and propulsive or non-propulsive movement phases of the arms and legs as well as average speed (V200), surface speed (V200surface) and swimming speed in turn zones (V200turns) were extracted. V200surface was significantly related to the percentage of leg propulsion and was shown to have large effect on VO2peakLG in the Cohen analysis. V200turns depended significantly on the indicators of physiological performance and body structure: TWAR, VO2peak LG and LBM, LBM, which in turn strongly determined the measured results of TWAR, TWLG, VO2peakAR and VO2peakLG. The V200turns and V200surface were strongly associated with V200, 0.92, p < 0.001 and 0.91, p < 0.001 respectively. In each lap of the 200m swimming there was an increased percentage of propulsion of limb movement observed simultaneously with a reduction in the gliding phase in the breaststroke cycles.

Key points

  • This study investigated the influence of the selected indicators of somatic properties and physiological capacity as well kinematic and coordination parameters on breaststroke swimming.
  • In this observations the body’s functional capacity have an important impact on achieving good breaststroke swimming results, the V200 was moderately associated on VO2peakLG, moreover, separate V200turns depended with VO2peakLG and on LBM and TWAR.
  • The speed of surface breaststroke swimming - V200surface similarly as V200turns had a very strong influence on the end result of V200 , 0.91, p<0.001 and 0.92, p<0.001 respectively.
  • The ability to swim fast on the surface (V200surface) was positively and significantly associated with the percentage time of propulsion generation -LP in the breaststroke cycle.
Key words: Breaststroke swimming, physiological indices, lean body mass, kinematic indices  相似文献   
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AIM: Epidemiological data show that citizens of small towns and villages have presented worse trends in cardiovascular mortality during the political, social and economic transformation in Poland during past 15 years than citizens of large towns. To try to eliminate these inequalities the Polish 400 Cities Project (P400CP), a large educational and interventional project, was prepared. The project consists of two arms: medical and social interventions. MATERIAL AND METHODS: The main aim of the medical screening intervention in P400CP is to increase detection and control of cardiovascular risk factors in inhabitants of 418 small cities (<8000 inhabitants) and surrounding villages, particularly in men and people of lower education. In 2003 and 2004 the P400CP covered 123 cities. All together, 36 696 subjects aged between 18 and 98 years were examined. In all participants, blood pressure (BP), anthropometric measurements, laboratory tests and questionnaire interviews were performed. The social arm of P400CP is one of multi-level educational intervention. Modern techniques of social psychology and marketing were involved to increase participation in interventions. RESULTS: Only 12.5% of all subjects had normal BP, cholesterol (<190 mg/dl) and glucose (<100 mg/dl in whole capillary blood) levels. During the first screening visit 65.5% of all examined subjects had BP>/=140 mmHg or >/=90 mmHg. The fasting glucose level was increased in 19% of women and 26% of men. Almost two-third of all subjects had a total cholesterol level above the norm. CONCLUSIONS: The prevalence of cardiovascular risk factors in participants of the screening programme P400CP in small towns in Poland was very high. High prevalence and low control of risk factors in participants of the P400CP confirm the decision to target this programme at citizens of small towns and villages.  相似文献   
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