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排序方式: 共有576条查询结果,搜索用时 15 毫秒
1.
Xenofon Giannakopoulos Panagiotis Chambilomatis loannis Filiadis Agathi Ntourntoufi Styliani Andronikou Alciviadis Kammenos 《International journal of urology》1997,4(3):324-326
Torsions of the spermatic cord occurring from the intrauterine period to the end of the first year of life are termed perinatal. These are divided into prenatal and postnatal torsions, depending on their occurrence in the intrauterine or postuterine period. From January 1984 to January 1996, 6 cases were identified at our institution, involving 4 prenatal and 2 postnatal extravaginal torsions of the spermatic cord. These cases are reviewed with regard to optimal therapeutic approaches for the treatment of both the affected gonad as well as the contralateral one, and whether the event occurred prenatally or postnatally. The authors also propose several clinical indications useful for obstetricians, pediatricians, urologists and nurses. 相似文献
2.
Mycoplasma pneumatoceles. 总被引:1,自引:0,他引:1
3.
Summary The purpose of this study was to investigate the relationship between threshold points for heart rate (
) and blood lactate (Th1a) as determined by two objective mathematical models. The models used were the mono-segmental exponential (EXP) model of Hughson et al. and the log-log (LOG) model of Beaver et al. Inter-correlations of these threshold points and correlations with performance were also studied. Seventeen elite runners (mean, SD = 27.5, 6.5 years; 1.73, 0.05 m; 63.8, 7.3 kg; and maximum oxygen consumption of 67.8, 3.7 ml · kg–1 · min–1) performed two maximal multistage running field tests on a 183.9-m indoor track with inclined turns. The initial speed of 9 km · h–1 (2.5 m · s–1) was increased by 0.5 km · h–1 (0.14 m · s–1) every lap for thef
c test and by 1 km · h–1 (0.28 m · s–1) every 4 min for the la test. After fitting the la or thef
c data to the two mathematical models, the threshold speed was assessed in the LOG model from the intersection of the two linear segments (LOG-1a; LOG-f
c) and in the EXP model from a tangent point (TI-1a; TI-f
c). Th1a and
speeds computed with the two models were significantly different (P<0.001) and poorly correlated (LOG-1a vs LOG-f
c:r=0.36, TI-1a vs TI-f
c:r=0.13). In general,
were less well correlated with performance than Th1a. With two different objective mathematical models, this study has shown significant differences and poor correlations between Th1a and
. Thus thef
c inflection point with Conconi's protocol is a poor indicator of the la breakpoint with a conventional multistage protocol and a weaker indicator of running performance. 相似文献
4.
Savvas P. Tokmakidis Luc A. Léger Theophilos C. Pilianidis 《European journal of applied physiology》1998,77(4):333-342
The purpose of this study was to compare various methods and criteria used to identify the anaerobic threshold (AT), and to correlate the AT obtained with each other and with running performance. Furthermore, a number of additional points throughout the entire range of lactate concentrations [La?] were obtained and correlated with performance. A group of 19 runners [mean age 33.7 (SD 9.6) years, height 173 (SD 6.3) cm, body mass 68.3 (SD 5.4)?kg, maximal O2 uptake (V˙O2 max ) 55.2 (SD 5.9)?ml?·?kg?1?·?min?1] performed a maximal multistage treadmill test (1?km?·?h?1 every 3.5?min) with blood sampling at the end of each stage while running. All AT points selected (visual [La?], 4?mmol?·?l?1 [La?], 1?mmol?·?l?1 above baseline, log-log breakpoint, and 45° tangent to the exponential regression) were highly correlated one with another and with performance (r?>?0.90) even when there were many differences among the AT (P?0.05). The additional points (ranging from 3 to 8?mmol?·?l?1 [La?], 1 to 6?mmol?·?l?1 [La?] above the baseline, and 30 to 70° tangent to the exponential curve of [La?]) were also highly correlated with performance (r?>?0.90). These results failed to demonstrate a distinct AT because many points of the curve provided similar information. Intercorrelations and correlations between AT and performance were, however, reduced when AT were expressed as the percentage of maximal treadmill speed obtained at AT or percentage of V˙O2 max . This would indicate that different attributes of aerobic performance (i.e. maximal aerobic power, running economy and endurance) are measured when manipulating units. Thus, coaches should be aware of these results when they prescribe an intensity for training and concentrate more on the physiological consequences of a chosen [La?] rather than on a “threshold”. 相似文献
5.
Introduction Little data exists on epidemiological trends of diverticular disease (DD). This study of 2,979 admissions over 10 years aimed
to examine the epidemiological trends of DD admissions and clinical outcomes.
Methods A retrospective analysis of all admissions with DD from 1995 to 2004 was performed. General population data for the area was
obtained from the national Census and local primary care trust.
Results Annual admissions for DD increased from 71 to 263 (p = 0.000). There was a trend of decreasing mean age from 71.2 years in 1995 to 68.1 in 2004 (p = 0.06). Admissions younger than 50 years increased from eight in 1995 to 42 in 2003 (p = 0.005). The mean age and size of the catchment population remained stable in that time. More emergency admissions underwent
surgery (14.4%, n = 54) than electives (6.1%, n = 66) and had longer lengths of stay (25.2 vs. 9.2 days; p = 0.000). More patients under 50 (19.6%, n = 21) had surgery compared with older ones (8.8%, n = 100; p = 0.000). Recurrent admissions increased from 18 to 72 per year (p = 0.000) but were not associated with poor clinical outcomes. There were 21 deaths overall. Deaths were more likely in emergencies
(p = 0.000, OR = 56.42) and those aged over 80 (p = 0.000, OR = 2.87). Mortality was independent of co-morbidity and other demographic factors.
Conclusion DD admissions increased, unexplained by an ageing population, increasingly affecting younger patients who are more likely
to undergo surgery, particularly as emergencies. Emergency admissions are associated with longer stay and higher mortality.
Recurrent admission cannot be used as guide to elective surgery. Efforts should be made to treat more DD electively. 相似文献
6.
Trika CO Zakopoulos N Toumanidis ST Stamatelopoulos SF Moulopoulos SD 《Cardiology》2004,102(2):108-114
BACKGROUND: Impaired left ventricular diastolic function is a common finding in essential hypertension. METHODS: In order to investigate possible relationships between flow velocity through the mitral valve (E/A; index of left ventricular diastolic function) and 24-hour blood pressure and heart rate variations, 198 patients with mild to moderate essential hypertension were studied by Doppler echocardiography and ambulatory blood pressure monitoring. They were divided according to age into group 1 (n = 88, age 40-54 years) and group 2 (n = 110, age 55-79 years). Each group was divided into subgroups with (1a, 2a) or without (1b, 2b) left ventricular hypertrophy according to the end-diastolic posterior wall thickness and/or the interventricular septum thickness. RESULTS: In a multivariate stepwise regression analysis, age (beta = -0.25, p < 0.0001), posterior wall thickness (beta = -0.31, p < 0.0057) and mean heart rate during the day (beta = -0.34, p < 0.0284) were the independent predictors of E/A in the pooled population. In group 1a (young subjects with left ventricular hypertrophy), mean systolic blood pressure during the night (beta = -0.33, p < 0.041) was the only independent predictor of E/A. In the elderly group without left ventricular hypertrophy (group 2b), the mean heart rate during the day (beta = -0.44, p < 0.0000) and mean pulse pressure during the night (beta = -0.60, p < 0.0007) were the independent predictors of E/A. CONCLUSIONS: The new finding provided by this study is that in elderly hypertensive patients without left ventricular hypertrophy, a large pulse pressure at night may serve as an independent predictor of abnormal left ventricular diastolic filling. 相似文献
7.
CT is a diagnostic tool with many clinical applications. The CT voxel intensity is related to the magnitude of X-ray attenuation, which is not unique to a given material. Substances with different chemical compositions can be represented by similar voxel intensities, making the classification of different tissue types challenging. Compared to the conventional single-energy CT, spectral CT is an emerging technology offering superior material differentiation, which is achieved using the energy dependence of X-ray attenuation in any material. A specific form of spectral CT is dual-energy imaging, in which an additional X-ray attenuation measurement is obtained at a second X-ray energy. Dual-energy CT has been implemented in clinical settings with great success. This paper reviews the theoretical basis and practical implementation of spectral/dual-energy CT. 相似文献
8.
Mimidis K Papadopoulos V Katsinelos P Deftereos S Filippou D Kartalis G 《Romanian journal of gastroenterology》2004,13(1):39-41
Gastrocolic fistula is rarely described in the literature. It has been associated with a variety of diseases and recently with benign gastric ulcers related to the use of nonsteroidal anti-inflammatory drugs (NSAIDs'). The present case represents the first report of gastrocolic fistula due to NSAIDs in a cirrhotic patient. This is in keeping with the established knowledge that cirrhotic patients constitute a high-risk group of patients when treated with NSAIDs'. Review of the literature shows that this condition warrants a complete diagnostic work-up to exclude more ominous underlined diseases. 相似文献
9.
10.