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排序方式: 共有822条查询结果,搜索用时 15 毫秒
1.
ALBERTO Q FARIAS LUCIANA L GONÇALVES EDUARDO LR CANÇADO ANTONIO C SEGURO SILVIA B CAMPOS CLARICE P ABRANTES-LEMOS FLAIR J CARRILHO 《Journal of gastroenterology and hepatology》2006,20(1):147-152
Background and Aims: Primary biliary cirrhosis (PBC) might be complicated by osteoporosis, whose etiology remains unknown but seems to be multifactorial. Prevalence rates of 30% to 60% for distal renal tubular acidosis (DRTA) have been reported in PBC patients, generally as incomplete DRTA. Although it is undisputed that a reduced bone mineral density (BMD) is the expected outcome among patients who have been suffering from longstanding chronic metabolic acidosis, it is unclear if incomplete DRTA is also associated with metabolic bone disease in PBC patients. The present study was undertaken to compare the BMD of PBC patients with and without DRTA.
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients. 相似文献
Methods: The BMD of 23 PBC patients (11 with DRTA and 12 without), all with normal clearance of creatinine, was assessed by dual energy radiograph absorptiometry. The diagnosis of DRTA was made if the urine pH was above 5.4 in all samples after the oral acid overload, showing tubular inability to acidify urine in the presence of test-induced systemic metabolic acidosis.
Results: Densitometric signs of osteoporosis were found in 82% of DRTA cases and in 83% of patients without DRTA (difference not significant). There were no significant differences in BMD measurement, T and Z scores of patients with and without DRTA.
Conclusions: The present study could not support a correlation between the presence of DRTA and the bone loss observed in PBC patients. 相似文献
2.
The association of diet, obesity, and breast cancer in Hawaii. 总被引:1,自引:0,他引:1
M T Goodman A M Nomura L R Wilkens J Hankin 《Cancer epidemiology, biomarkers & prevention》1992,1(4):269-275
A case-control study of the association of dietary fat and animal protein consumption with breast cancer was conducted between 1975 and 1980 on Oahu, Hawaii. Data from this study were used to explore the relation of selected foods and the interaction of nutrients and foods with other factors, such as body size, age at menopause, and ethnicity on the risk for breast cancer. The sample included 272 postmenopausal breast cancer cases and 296 neighborhood controls. Study participants included Japanese and Caucasian women, aged 45 to 74, who were residents of Oahu. There was a suggestion of a positive-dose response relation (P < 0.01) between sausage consumption and the odds ratio for breast cancer. Significant odds ratios for breast cancer were also found for higher intakes (above the 50th percentile) of diary items, sausage, and all meats combined. The dose-response relation for nutrients and foods tended to be stronger among women with a high Benn's index (kg/cm1.5182) compared to women with a low Benn's index. In general, subjects with high dietary intakes of fat and animal protein who were in the upper 50th percentile of body size were at the greatest risk for breast cancer. However, there was no evidence for an interaction between the dietary variables and body size, ethnic group, age at menarche, age at menopause, or age at first birth that would affect the odds ratio for breast cancer. These data suggest that women with both a high intake of foods rich in fat and animal protein and with a large body size are at increased risk for breast cancer. 相似文献
3.
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services. 相似文献
4.
5.
Urban Sester Barbara C. Gärtner Heinrike Wilkens Bernhard Schwaab Rolf Wössner Ingrid Kindermann Matthias Girndt reas Meyerhans Nikolaus Mueller-Lantzsch Hans-Joachim Schäfers Gerhard W. Sybrecht Hans Köhler Martina Sester 《American journal of transplantation》2005,5(6):1483-1489
Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation. 相似文献
6.
MGC Hendriks P Dogterom JT Ebels B Oosterhuis LR Geertsema T Hulot G Bianchetti and JHG Jonkman 《Fundamental & clinical pharmacology》1998,12(5):559-565
Summary— In the present study we have compared the steady state biopharmaceutic characteristics of four diltiazem once daily controlled release capsules: Mono-Tildiem LP 300® (300 mg), Adizem® XL (300 mg)1, Cardizem® (300 mg) and Dilacor® (240 mg). Sixteen healthy male volunteers (aged 22.9 ± 3.3 years, range 19–31 years) completed an open label, multiple oral dose, randomized, four-period crossover study without a washout period in between. The volunteers received each diltiazem formulation once daily for four days. Trough diltiazem and metabolites plasma concentrations were determined on days 3 and 4. The 24-h plasma concentration-time profiles were assessed after the dose on day 4 of each period. The following steady state pharmacokinetic parameters for diltiazem were calculated: the minimum plasma concentration (cmin), the maximum plasma concentration (cmax), the time to reach that concentration (tmax), the time interval during which the plasma concentration exceeds 50% of cmax (t50), the area under the plasma concentration-time curve (AUC72–96) and the peak-to-trough fluctuation (PTF). For the metabolites of diltiazem, N-mono-desmethyl-diltiazem (NDM) and desacetyldiltiazem (DAD), AUC72–96 (AUCNDM and AUCDAD) and the ratio metabolite/parent compound were calculated. Steady state was achieved on day 3. Except one, all controlled release formulations have satisfactory controlled release properties allowing once daily administration. However, significant (P < 0.05) differences were found between the pharmacokinetic characteristics which do not allow exchange of the various formulations. Concentrations well below 50 ng·mL-1 in the morning hours were observed for Dilacor® (240 mg) and Adizem® XL (300 mg), which could be a disadvantage of these formulations as it is well-known that ischaemic events occur at a higher rate during that part of the day. The plasma concentration profiles of NDM and DAD, the major circulating metabolites, parallel the plasma concentration profiles for the parent compound. From a clinical point of view, all treatments were well tolerated. 相似文献
7.
I. C. Chi L. R. Wilkens C. B. Champion R. E. Machemer R. Rivera 《Advances in Contraception》1989,5(2):101-119
The possible effect of breastfeeding on intrauterine device (IUD) insertion events was investigated. Analysis included a total of 6493 women who enrolled in multicenter IUD clinical trials over a ten-year period. Findings indicate that breastfeeding exerts a protective effect on the incidence of moderate to severe insertional pain and reduces the need for cervical dilatation to facilitate insertion. The pain protection effect was most evident in breastfeeding women who were still in lactational amenorrhea. Subjects with amenorrhea, both breastfeeding and non-breastfeeding, had a significantly lower incidence of pain at IUD insertion than the corresponding menstruating subjects. This effect may be related to a higher secretion of beta-endorphin in the breastfeeding and lactational amenorrheic subjects.
Resumen Se investigaron en este estudio los posibles efectos del amamantamiento sobre la inserción de dispositivos intrauterinos (DIU). El estudio comprendió 6493 mujeres que participaron en ensayos clínicos en diversos centros durante un período de diez años. Los resultados indican que el amamantamiento ejerce un efecto protector contra la aparición de dolores moderados a fuertes en el momento de la inserción y reduce la necesidad de dilatar el cuello del útero para facilitar la inserción. Este efecto de protección contra el dolor predominó entre las mujeres que amamantaban y se hallaban aún en amenorrea de lactación. Las mujeres con amenorrea, tanto las que amamantaban como las que no lo hacían, señalaron un nivel de dolor significativamente menor en el momento de inserción del DIU que aquéllas cuyo ciclo menstrual se había reanudado. Este efecto puede estar relacionado con una mayor secreción de -endorfina en las mujeres en período de amamantamiento o de amenorrea de lactación.
Resumé Cette étude présente les effets possibles de l'allaitement au sein sur des phénomènes liés à l'insertion de dispositifs intra-utérins (DIU). La recherche portait 6493 femmes inscrites dans plusieurs centres pour participer à des essais cliniques pendant une période de dix ans. On a constaté que l'allaitement au sein a un effet protecteur contre l'apparition de douleurs modérées à fortes au moment de l'insertion et qu'il réduit la nécessité de dilater le col utérin en vue de faciliter l'insertion. Cet effet de protection contre les douleurs prédominait chez les femmes qui allaitaient et se trouvaient encore en aménorrhéc de lactation. Les douleurs au moment de l'insertion étaient significativement moins fréquentes au moment de la pose du DIU chez celles qui, allaitant ou non, étaient encore en période d'aménorrhée, que chez celles dont le cycle menstruel avait repris. Cet effet peut être lié à une sécrétion plus abondante de -endorphine chez les femmes en période d'allaitement ou d'aménorrhée de lactation.相似文献
8.
9.
Ludwig Wilkens Joelle Tchinda Dagmar Burkhardt Hans Heinrich Kreipe 《Pathobiology》2002,70(4):204-208
OBJECTIVE: Comparative genomic hybridization (CGH) has been established as an informative technique in genetic analysis. However, differences in the ratio of hybridization intensities were reported for particular chromosomes, which may affect CGH results. The aim of this study was to define these differences in more detail. For this purpose, CGH results of 70 samples of bone marrow cells (BMC) with normal karyotype in conventional cytogenetics (CC) were evaluated using seven different reference DNAs and two different DNA labeling systems. METHODS AND RESULTS: CGH using fluorochrome-conjugated nucleotides for DNA labeling indicated signal deviations in 21/70 BMC samples. Deviations affected chromosomes 1 (n = 21), 2 (n = 11), 4 (n = 11), 5 (n = 9), 6 (n = 7), 7 (n = 2), 8 (n = 2), 12 (n = 5), 13 (n = 15), 14 (n = 1), 16 (n = 17), 17 (n = 11), 19 (n = 21), 20 (n = 12), and/or 22 (n = 17). None of the imbalances were confirmed by fluorescence in situ hybridization (FISH). Using digoxigenin and biotin-conjugated nucleotides in exemplary cases (n = 5) led to the disappearance of the signal deviations. Repeated CGH experiments using seven different reference DNAs showed remarkable variations in the signal deviations. CONCLUSION: Hybridization differences depend not only on the hapten or fluorochrome-labeled nucleotides used for DNA labeling, but also on the reference DNA chosen. Therefore, close control of CGH experiments is mandatory, and additional techniques such as FISH should be performed to confirm the results obtained by CGH. 相似文献
10.
Human leukocyte antigen matching and fetal loss: results of a 10 year prospective study 总被引:6,自引:0,他引:6
Ober C; Hyslop T; Elias S; Weitkamp LR; Hauck WW 《Human reproduction (Oxford, England)》1998,13(1):33-38
The role that maternal and fetal human leukocyte antigen (HLA) genes play
in pregnancy is unknown, but it has been suggested that fetuses whose HLA
alleles do not differ from maternal alleles (i.e. histocompatible fetuses)
are more likely to be aborted than fetuses with HLA alleles that differ
from maternal alleles (i.e. histoincompatible fetuses). To elucidate the
role of HLA compatibility in pregnancy, we tested the hypothesis that
couples who match for HLA alleles or haplotypes would have reduced
fertility because only these couples could produce histocompatible fetuses.
We conducted a 10 year prospective study of HLA matching and pregnancy
outcome in 111 Hutterite couples, providing information on 251 pregnancies.
A logistic regression analysis was performed to determine the effects of
HLA matching at HLA regions and loci on pregnancy outcome (fetal loss
versus delivery). Significantly increased fetal loss rates were observed
among couples matching for the entire 16-locus haplotype (P = 0.002). Among
the individual loci, loss rates were increased among couples matching for
HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P =
0.043). We interpret these results as evidence that matching for the entire
16-locus haplotype and/or alleles at an HLA-B-linked locus confers
significant risk for fetal loss.
相似文献