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排序方式: 共有627条查询结果,搜索用时 15 毫秒
1.
Sung Hee Chung Olof Heimbürger Bengt Lindholm Hi Bahl Lee 《Nephrology, dialysis, transplantation》2005,20(6):1207-1213
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated. 相似文献
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The detergent-soluble extract of rat ovary plasma membranes contained a Gs protein of about 100 kDa as shown by its elution behavior on a Bio Gel A-1.5m column. However, the cell membranes exposed to hCG (37° C, 15 min) contained in addition a higher molecular weight Gs protein complex of 300 kDa comprised of human chorionic gonadotropin (hCG) receptor (hCGR) and Gs. The complex bound with an affinity column of GTP-Sepharose and could be released with Gpp(NH)p and GTP inhibited this binding. The presence of the hCGR in the complex was shown by its binding to 125I-hCG. Furthermore, GTP inhibited the binding of hCG to the complex. These results indicate the presence of hCGR and Gs protein complex in the hCG-treated membranes. hCGR and Gs protein were individually purified and reconstituted into phospholipid vesicles. The protein-phospholipid vesicles showed saturation kinetics of binding of 125I-hCG and 3H-Gpp(NH)p. Incubation of phospholipid vesicles with hCG resulted in a 2–3-fold increase in the binding of 3H-Gpp(NH)p and GTPase activity. Activation of Gs protein was dependent on the length of incubation and the hormone concentration. Deglycosylated hCG was about 10 times less potent than hCG suggesting a role of carbohydrates of hCG in inducing hCG-Gs protein interactions. The data with the in vitro reconstitution system rule out the involvement of a carbohydrate-binding lectin in the function of the hormone. 相似文献
5.
Use of antidepressant medications and the possible association with breast cancer risk. A review 总被引:1,自引:0,他引:1
BACKGROUND: Antidepressant medication use has dramatically increased over the past decade, particularly for the newer classes such as selective serotonin reuptake inhibitors. While there is no question about the usefulness of these medications, it is important to review animal and epidemiologic studies that have evaluated the association between antidepressant medication use and the risk of breast cancer. METHODS: This paper reviews the scientific literature pertaining to the prevalence of and indications for antidepressant medication use, and the possible association between antidepressant medication use and breast cancer risk. RESULTS: Antidepressant medications are most commonly indicated for depressive disorders, and are also used for other conditions (e.g., anxiety disorders, personality disorders, and pain). In addition, antidepressants may be an effective alternative to estrogen therapy for the alleviation of hot flashes among peri-/postmenopausal women. Several epidemiologic studies have reported that certain antidepressants may be associated with a slightly increased breast cancer risk; however, the literature remains inconsistent. CONCLUSIONS: The possibility of an association between certain antidepressant medications and breast cancer risk has not been excluded, although further studies are needed before the body of scientific evidence can be conclusive. Evidence to date does not support a change in the current use of antidepressant medications. 相似文献
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M. A. Trevethick N. M. Clayton A. K. Bahl P. Strong I. W. Harman 《Inflammation research》1994,41(3-4):179-183
The potential involvement of leukotrienes in the pathogenesis of indomethacin-induced ulceration of the rat gastric antrum has been studied. Pretreatment with the leukotriene biosynthesis inhibitor, MK886 (30 mg/kg p.o.), inhibited the increases in blood and antral leukotriene B4 releaseex vivo associated with the evolution of antral ulceration. Despite this, however, there was no significant reduction in either the area of antral ulceration, or in the associated blood neutrophilia and neutrophil infiltration into the gastric antrum. Similarly, pretreatment with the leukotriene B4 antagonist, SC41930 (50 mg/kg p.o.) or the peptidyl leukotriene antagonist ICI198,615 (50 mg/kg p.o.) did not inhibit the area of antral ulceration induced by indomethacin.Thus, in contrast to published reports studying fundic ulceration, our results suggest that leukotrienes do not play a major role either in the pathogenesis of indomethacin-induced ulceration of the rat gastric antrum or neutrophil infiltration into the damaged antrum. 相似文献
8.
Chopra A Bahl RK Puri RK Gill SS 《Indian journal of dermatology, venereology and leprology》1996,62(2):110-111
A 45-year-old woman with livid plaques showing central atrophy and erythematous vesicular borders over both dorsa of feet and buttocks, and follicular and papular lesions over buttocks and lumbar area, was difficult to diagnose as either lichen planus (LP) or lupus erythematosus (LE). The histological studies from two places showed features of both LE and LP. Laboratory findings were within normal limits first, but follow up studies for two years showed persistent albuminurea, leucopenia, arthritis and erythema over the exposed areas with same histology suggesting that eruption may be an unusual variant of LE. 相似文献
9.
Simultaneous quantification of isoniazid,rifampicin, ethambutol and pyrazinamide by liquid chromatography/tandem mass spectrometry 下载免费PDF全文
Julie B. Prahl Marika Lundqvist Justyna M. C. Bahl Isik S. Johansen Åse B. Andersen Niels Frimodt‐Møller Arieh S. Cohen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(11):1004-1015
A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM. 相似文献
10.
Tarun Shankar Choudhary Akanksha Srivastava Ranadip Chowdhury Sunita Taneja Rajiv Bahl Jose Martines Maharaj Kishan Bhan Nita Bhandari 《Maternal & child nutrition》2019,15(4)
Burden and risk factors for wasting in the first 6 months of life among Indian children are not well documented. We used data from India's National Family Health Survey 4 to estimate the prevalence of severe wasting (weight for length < ‐3 SD) among 18,898 infants under 6 months of age. We also examined the association of severe wasting with household, maternal, and child‐related factors using multivariable logistic regression analysis. Prevalence of severe wasting among infants less than 6 months of age was 14.8%, ranging from 3.5 to 21% across states. Low birth weight (<2,500 g; adjusted odds ratio [AOR] 1.40, 95% CI [1.19, 1.65]), nonutilization of supplementary nutrition by mother during lactation (AOR 1.23, 95% CI [1.05, 1.43]), and anthropometric assessment during summer (AOR 1.37, 95% CI [1.13, 1.65]) and monsoon months (AOR 1.53, 95% CI [1.20, 1.95]) were associated with higher odds of severe wasting. Infants aged 2 to 3 months (AOR 0.78, 95% CI [0.66, 0.93]) and 4 to 5 months (AOR 0.65, 95% CI [0.55, 0.73]) had lower odds of severe wasting as compared with the 0‐ to 1‐month category. This analysis reveals a high burden of severe wasting in infants less than 6 months in India. Preventive interventions must be targeted at reducing low birth weight due to fatal growth restriction and prematurity. Appropriate care practices at facilities and postdischarge with extra attention to those born small and sick can prevent further deterioration in nutritional status. 相似文献