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排序方式: 共有1619条查询结果,搜索用时 15 毫秒
1.
Ihsan A. Badr 《International ophthalmology》1993,17(3):155-160
The region is characterized by diversity in cultural, political, economic and health conditions. Blindness in the region varies from 6.4% to 0.2% with cataract ranking highly as an underlying cause. There is a need to develop national policies to deliver affordable, technically suitable, and cost effective management plans to reduce cataract. Economic, demographic, health, and manpower statistics are essential information to be considered in formulating such policies. 相似文献
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Contin Educ Anaesth Crit 相似文献
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Steven N Singh X Charlene Tang Bramah N Singh Paul Dorian Domenic J Reda Crystal L Harris Ross D Fletcher Satish C Sharma J Edwin Atwood Alan K Jacobson H Daniel Lewis Becky Lopez Dennis W Raisch Michael D Ezekowitz 《Journal of the American College of Cardiology》2006,48(4):721-730
OBJECTIVES: The purpose of this study was to determine quality of life (QOL) and exercise performance (EP) in patients with persistent atrial fibrillation (AF) converted to sinus rhythm (SR) compared with those remaining in or reverting to AF. BACKGROUND: Restoration of SR in patients with AF improving QOL and EP remains controversial. METHODS: Patients with persistent AF were randomized double-blind to amiodarone, sotalol, or placebo. Those not achieving SR at day 28 were cardioverted and classified into SR or AF groups at 8 weeks (n = 624) and 1 year (n = 556). The QOL (SF-36), symptom checklist (SCL), specific activity scale (SAS), AF severity scale (AFSS), and EP were assessed. RESULTS: Favorable changes were seen in SR patients at 8 weeks in physical functioning (p < 0.001), physical role limitations (p = 0.03), general health (p = 0.002), and vitality (p < 0.001), and at 1 year in general health (p = 0.007) and social functioning (p = 0.02). Changes in the scores for SCL severity (p = 0.01), functional capacity (p = 0.003), and AFSS symptom burden (p < 0.001) at 8 weeks and in SCL severity (p < 0.01) and AF symptom burden (p < 0.001) at 1 year showed significant improvements in SR versus AF. Symptomatic patients were more likely to have improvement. The EP in SR versus AF was greater from baseline to 8 weeks (p = 0.01) and to 1 year (p = 0.02). The EP correlated with physical functioning and functional capacity except in the AF group at 1 year. CONCLUSIONS: In patients with persistent AF, restoration and maintenance of SR was associated with improvements in QOL measures and EP. There was a strong correlation between QOL measures and EP. 相似文献
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Reda M. El-S. Hassanine Mohammed O. Al-Jahdali 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(3):289-295
During June and July of 2007, a total of 130 specimens of the fish Rastrelliger kanagurta Cuvier (Teleostei, Scombridae), ranging between 19–31 cm in total length, were caught in the Red Sea off the coast of Sharm
El-Sheikh, South Sinai, Egypt, and examined for infections by acanthocephalans (65 fish/month). Of this number, 29 (22.30%)
were slightly or heavily parasitized by the acanthocephalan Diplosentis nudus (Harada, 1938) Pichelin et Cribb, 2001 (Cavisomidae); no other helminth parasites were found in the intestine of R. kanagurta. Twenty-nine infrapopulations of D. nudus, ranging from 23–218 individuals were collected from the infected fishes. These infrapopulations were distributed in a well-defined
fundamental niche along the intestine of R. kanagurta, where the distribution of male worms was not random with respect to female worms size and position and suggests that the
male-male competition for access to female may be intense and may select for large males. No correlation between fish size
and infrapopulation size was observed. Correlations between female-to-male sex ratio and infrapopulation size, numbers of
females and their mean lengths, numbers of males and their mean lengths, mean female length and mean male length within infrapopulation
were very strong, and clearly suggest that as the infrapopulation size increased, the number of females and their mean lengths
decreased and the number of males and their mean lengths increased. Combination of these results strongly suggests density-dependent
effects and competition between male worms. The relationship between the mean female length or size and the number of eggs
within its pseudocoel was strongly positive; egg production by female worm significantly decreases as the infrapopulation
size increases, suggesting density-dependent reduction in female worm fecundity. Tendency for the variability in male testes
size was not significant in infrapopulations of D. nudus. All of these results are discussed. 相似文献
8.
Maximal dynamic expiratory pressures are higher when forced expiration is preceded by a fast inspiration to total lung capacity
(TLC) than when preceded by a slow inspiration and a few seconds pause at TLC. We hypothesized that these pressure differences
are due to the stretch-shorten cycle (SSC), which refers to enhancement of muscle force when a concentric muscle contraction
is immediately preceded by an eccentric contraction. Seven volunteers [36 (2) years; mean (SEM)] performed maximal forced
expirations against minimal resistance with fast (F) or slow (S) maneuvers. F maneuvers consisted of a fast inspiration to
TLC followed immediately by a fast expiration, whereas S consisted of a slow inspiration to TLC and a 4- to 5-s pause at TLC
prior to forced expiration. We measured esophageal pressure (P
es), peak expiratory flow rate (PEFR), and the EMG activity of the transversus abdominis (Tr) by means of intramuscular fine-wire
electrodes. The subjects performed several runs of each maneuver in a random order, and runs with the greatest expiratory
P
es were analyzed. In comparison with S, F yielded greater P
es [182 (15) versus 167 (15) cmH2O; P=0.003)] but similar PEFR [9.8 (0.7) versus 9.6 (0.7) l/s, P>0.05] and EMG activity of the Tr during forced expiration [221 (31) versus 208 (34) a.u., P>0.05]. Further analysis revealed significant EMG activity of Tr during end-inspiration (eccentric contraction) with F maneuvers
only [73 (22) versus 32 (17) a.u., P<0.05]. We conclude that the ability of expiratory muscles to generate greater P
es with F maneuvers is related to the sequence of an eccentric contraction, which is followed immediately by concentric contraction
in a manner analogous to SSC described in skeletal muscles.
Electronic Publication 相似文献
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Endoglin (CD105) and vascular endothelial growth factor as prognostic markers in colorectal cancer. 总被引:11,自引:0,他引:11
Reda S Saad Yulin L Liu Girija Nathan James Celebrezze David Medich Jan F Silverman 《Modern pathology》2004,17(2):197-203
Endoglin (CD105) has been shown to be a more useful marker to identify proliferating endothelium involved in tumor angiogenesis than panendothelial markers such as CD31. We investigated endoglin and vascular endothelial growth factor expression as possible prognostic markers in colorectal cancer. Surgical specimens from 150 patients with resected colorectal carcinomas were immunostained for endoglin, CD31 and vascular endothelial growth factor. Colorectal carcinoma cases consisted of 50 cases without lymph node metastases, 50 cases with only lymph node metastases and 50 cases with liver metastases (38 cases also had positive lymph nodes). Positively stained microvessels were counted in densely vascular foci (hot spots) at x 400 fields in each specimen. For vascular endothelial growth factor, intensity of staining was scored on a three-tiered scale. Results were correlated with other prognostic parameters. Endoglin demonstrated significantly more proliferating neoplastic microvessels than CD31 (31+/-10 vs 19+/-8/0.15 mm2 field, P<0.001). Low vascular endothelial growth factor expression within tumor cells was seen in 49 (33%) and high expression in 101 cases (67%). There was a positive correlation of endoglin, CD31 counts and vascular endothelial growth factor overexpression with the presence of angiolymphatic invasion and lymph node metastases (P<0.05). Only endoglin counts correlated significantly with liver metastases and positive vascular pedicle lymph nodes (P<0.05), while vascular endothelial growth factor showed significant correlation with the depth of invasion (P<0.01). Endoglin, by staining higher numbers of the proliferating vessels in colon carcinoma, is a more specific and sensitive marker for tumor angiogenesis than the commonly used panendothelial markers. Endoglin staining also showed prognostic significance with positive correlation with angiolymphatic invasion and metastases to lymph nodes and liver. 相似文献