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排序方式: 共有320条查询结果,搜索用时 515 毫秒
31.
32.
Sichieri R Moura AS Genelhu V Hu F Willett WC 《The American journal of clinical nutrition》2007,86(3):707-713
BACKGROUND: Despite interest in the glycemic index diets as an approach to weight control, few long-term evaluations are available. OBJECTIVE: The objective was to investigate the long-term effect of a low-glycemic-index (LGI) diet compared with that of a high-glycemic-index (HGI) diet; all other dietary components were equal. DESIGN: After a 6-wk run-in, we randomly assigned 203 healthy women [body mass index (in kg/m2): 23-30] aged 25-45 y to an LGI or an HGI diet with a small energy restriction. The primary outcome measure was weight change at 18 mo. Secondary outcomes included hunger and fasting insulin and lipids. RESULTS: Despite requiring a run-in and the use of multiple incentives, only 60% of the subjects completed the study. The difference in glycemic index between the diets was approximately 35-40 units (40 compared with 79) during all 18 mo of follow-up, and the carbohydrate intake from energy remained at approximately 60% in both groups. The LGI group had a slightly greater weight loss in the first 2 mo of follow-up (-0.72 compared with -0.31 kg), but after 12 mo of follow-up both groups began to regain weight. After 18 mo, the weight change was not significantly different (P = 0.93) between groups (LGI: -0.41 kg; HGI: -0.26 kg). A greater reduction was observed in the LGI diet group for triacylglycerol (difference = -16.4 mg/dL; P = 0.11) and VLDL cholesterol (difference = -3.7 mg/dL; P = 0.03). CONCLUSIONS: Long-term weight changes were not significantly different between the HGI and LGI diet groups; therefore, this study does not support a benefit of an LGI diet for weight control. Favorable changes in lipids confirmed previous results. 相似文献
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IH Igbinosa UU Nwodo A Sosa M Tom AI Okoh 《International journal of environmental research and public health》2012,9(7):2537-2549
Pseudomonas species are opportunistic pathogens with implications in a wide range of diseases including cystic fibrosis and sickle cell anaemia. Because of their status as multidrug resistant (MDR) and extremely drug resistant (XDR) bacteria Pseudomonas species represent a threat to public health. Prevalence, antibiogram and associated antibiotic resistant genes of Pseudomonas species isolated from freshwater and mixed liquor environments in the Eastern Cape Province of South Africa were assessed. Polymerase chain reaction (PCR) based technique was used to identify the isolates and screen for antibiotic resistant genes. The result shows occurrence of Pseudomonas spp. in freshwater and mixed liquor as follows: 71.42% and 37.5% (P. putida), 14.28% and 31.25% (P. flourescens), 7.14% and 6.25% (P. aeruginosa) and 7.14% and 25% for other Pseudomonas species respectively. Disk diffusion antibiogram of the Pseudomonas isolates from the two locations showed 100% resistance to penicillin, oxacillin, clindamycin, rifampicin and 100% susceptibility to ciprofloxacin and gentamicin with varied percentage resistances to cephalothin, nalidixic acid, tetracycline, and ampicillin. The bla(TEM) antibiotic resistant gene was detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% P. aeruginosa and 40% in other Pseudomonas species. Similarly, Integrons conserved segment were detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% of P. aeruginosa and 40% of other Pseudomonas species. The presence of bla(TEM) gene and integrons conserved segment in some of the isolates is worrisome and suggest Pseudomonas species as important reservoirs of multidrug resistance genes in the Eastern Cape Province environment. 相似文献
35.
Brice W Beckstrom Scott H Horsley James P Scheetz Zafrulla Khan Anibal M Silveira Stephen J Clark Henry Greenwell Allan G Farman 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(3):359-366
OBJECTIVES: The objective of this study was to examine the prevalence of carotid area calcifications retrospectively detected on digital panoramic radiographs of pretreatment cancer subjects, and to correlate the finding of such calcifications with radiographic evidence of periodontal bone loss in the same subjects. STUDY DESIGN: Digital panoramic radiographs of 201 subjects were evaluated for calcifications projected in the carotid artery bifurcation area as well as for alveolar bone loss as a result of periodontal disease. Inclusion criteria were unobscured carotid artery bifurcation regions bilaterally and sufficient index teeth present with a definable cemento-enamel junction and alveolar crest. Radiographs were independently observed for carotid area calcifications and for periodontal status. Image enhancements permitted for detection of calcifications projected in the carotid area included window/level, inverse, and emboss. Periodontal measurements were made on index teeth using proprietary imaging software and a mouse-driven measurement algorithm. A 3-factor analysis of variance was performed with 3 between-subjects comparisons. Percentage of bone loss was the dependent variable. Independent variables were age, subject sex, and the presence or absence of carotid area calcifications. RESULTS: Differences measured in percentage of bone loss between sexes were not statistically significant. While bone loss did increase with age, comparison of the mean bone loss of each age category revealed no statistical significance. There was a highly significant correlation between carotid artery area calcifications visible on panoramic radiographs and percent alveolar bone loss. Radiographs showing unilateral and bilateral calcifications had a mean percent bone loss of 24.2% +/- 12.6% and 25.7% +/- 13.0% respectively, compared to those with no calcification at 10.4% +/- 9.9%. CONCLUSIONS: Nearly 1 in 4 subjects in this study evidenced calcifications projected in the carotid bifurcation region. The finding of such calcifications was significantly related to the calculated percentage of alveolar bone loss. 相似文献
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37.
Christopher A. Adejuwon Sheldon J. Segal Anibal Faundes Francisco Alvarez-Sanchez 《Contraception》1982,25(6):613-618
Starting from the 10th day of the menstrual cycle through onset of the subsequent menstrual bleeding, daily blood samples were collected from 14 women using Copper T IUDs and 10 normal control women. The serum samples were analysed by radioimmunoassay (RIA) for human prolactin (hPRL) and human luteinizing hormone (hLH). hPRL values were subjected to statistics. Episodic patterns of hPRL were observed for all subjects. IUD users show generally lower daily levels of hPRL than non-IUD users, but the apparent differences were statistically insignificant. 相似文献
38.
Barba J Rioja J Robles JE Rincón A Rosell D Zudaire JJ Berian JM Pascual I Benito A Errasti P 《World journal of urology》2011,29(4):547-553
Purpose
Renal Doppler ultrasonography (DUS) is the gold-standard image test for follow-up after renal transplantation, it is potentially useful to detect renal disease and it could be related with long-term survival. We evaluate whether renal graft survival can be predicted by immediate renal Doppler ultrasonography (IRDUS), defined as ultrasonography carried out in the first 24 h post-surgery. 相似文献39.
Martinez-Borges AR 《Medical hypotheses》2006,67(4):871-875
Benign prostatic hyperplasia (BPH) is the most common form of prostate disease in middle-aged and elderly men, and leads to severe impairment later in life. Despite its significant impact on public health, the underlying cause of BPH is yet to be determined. This hypothesis proposes a new causal factor for BPH. Applying concepts of dynamics of fluids to the process of urination it could be stated that a turbulent urinary flow through the passage of the urethra. The turbulent urinary flow in the urethra applies pressure and stretch forces to the surrounding tissue. This stimulus repeated over time and coupled with age-related changes of the urethral tissue could contribute to the development of BPH. In support of this hypothesis, several mechanotransduction studies have shown that vibration and pressure forces applied to different cell tissues can provoke cellular and molecular changes. Another supportive data is the presence of the hyperplasic reaction surrounding the urethra specifically located in the transition zone, the only zone where BPH develops. It is crucial to identify causal factors to understanding the disease and to determine effective primary prevention strategies. Future studies of the dynamics of fluids in the urethra are warranted. The finding of significant forces transmitted to the periurethral tissue from a turbulent urinary flow could give us the clue to the underlying cause of BPH. If this hypothesis proves to be valid there are several primary prevention measures that could be implemented to impede the development of BPH. Educational intervention measures in younger populations to avoid frequent urinary retention and active urination (process of forcing the urine through the urethra at a high velocity) could be considered. Studies of the impact of turbulence in the standing vs. sitting position during urination in men should also be considered. 相似文献
40.
Alberici LC Oliveira HC Patrício PR Kowaltowski AJ Vercesi AE 《Gastroenterology》2006,131(4):1228-1234
BACKGROUND & AIMS: Changes in mitochondrial energy metabolism promoted by uncoupling proteins (UCPs) are often found in metabolic disorders. We have recently shown that hypertriglyceridemic (HTG) mice present higher mitochondrial resting respiration unrelated to UCPs. Here, we disclose the underlying mechanism and consequences, in tissue and whole body metabolism, of this mitochondrial response to hyperlipidemia. METHODS: Oxidative metabolism and its response to mitochondrial adenosine triphosphate (ATP)-sensitive K+ channel (mitoK(ATP)) agonists and antagonists were measured in isolated mitochondria, livers, and mice. RESULTS: Mitochondria isolated from the livers of HTG mice presented enhanced respiratory rates compared with those from wild-type mice. Changes in oxygen consumption were sensitive to adenosine triphosphate (ATP), diazoxide, and 5-hydroxydecanoate, indicating they are attributable to mitochondrial ATP-sensitive K+ channel (mitoK(ATP)) activity. Indeed, mitochondria from HTG mice presented enhanced swelling in the presence of K+ ions, sensitive to mitoK(ATP) agonists and antagonists. Furthermore, mitochondrial binding to fluorescent glibenclamide indicates that HTG mice expressed higher quantities of mitoK(ATP). The higher content and activity of liver mitoK(ATP) resulted in a faster metabolic state, as evidenced by increased liver oxygen consumption and higher body CO(2) release and temperature in these mice. In agreement with higher metabolic rates, food ingestion was significantly larger in HTG mice, without enhanced weight gain. CONCLUSIONS: These results show that primary hyperlipidemia leads to an elevation in liver mitoK(ATP) activity, which may represent a regulated adaptation to oxidize excess fatty acids in HTG mice. Furthermore, our data indicate that mitoK(ATP), in addition to UCPs, may be involved in the control of energy metabolism and body weight. 相似文献