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排序方式: 共有372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
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Prior studies have shown that pneumothorax is one of the more difficult entities to diagnose with digitized radiography. This study was designed to test whether increasing resolution from 1.25 to 2.5 line pairs per millimeter (lp/mm) and image processing (edge enhancement from unsharp masking) would increase accuracy and confidence in the diagnosis of pneumothorax, as well as normal cases and other forms of lung disease. Conventional radiographs were digitized with use of a laser reader and then reformatted as film hard copy. Eleven observers read 35 cases reformatted in three different ways (1.25 lp/mm, 2.5 lp/mm, 1.25 lp/mm unsharp mask). The images with finer resolution (2.5 lp/mm) and unsharp mask images were superior to those with coarser resolution (1.25 lp/mm) for the diagnosis of pneumothorax. There was no difference in diagnostic accuracy for normal patients. For abnormalities other than pneumothorax, the unsharp mask images were significantly worse. Confidence in the diagnosis of pneumothorax and other abnormalities was highest with the finest resolution (2.5 lp/mm). 相似文献
5.
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
6.
This study examines relationships between growth data and energy expenditure, economic status, and family structure among Malian adolescent girls, aged 10–17 years living in the Segou Region of Mali. Classification and regression trees (CART) were used as the primary methodology to identify high‐risk subgroups for stunting (measured as height‐for‐age) in a sample of 1,103 Malian adolescents. Because CART has been used rarely to examine growth and development, this study provides a new way to better understand how economic status, family structure, and energy expenditure related factors influence stunting in Mali. The findings indicate that the greater the number of sisters and women in a household, the poorer the nutritional status of adolescent girls. The data also show that the presence of servants within the household may predict better nutritional success of young girls. Energy expenditure was an important predictor in the context of family structure regarding the number of sisters and the presence of servants. Wealth indicators did not appear in the final tree, suggesting that wealth may not play as great a role in predicting poor growth and nutritional status as family size and structure. In conclusion, classification trees may assist in understanding the interactive nature of predictive factors of stunting in this population, and further provide evidence for intervention programs aimed at improving the health and nutritional status of Malian adolescent girls. Am. J. Hum. Biol., 2008. © 2008 Wiley‐Liss, Inc. 相似文献
7.
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
8.
Schover LR; Thomas AJ; Falcone T; Attaran M; Goldberg J 《Human reproduction (Oxford, England)》1998,13(4):862-866
Many couples undergoing in-vitro fertilization (IVF) are at a higher risk
of having a child with a genetic abnormality. In a sample of 55 consecutive
couples starting IVF, only 33% had no genetic risk factor. The most common
genetic risks were advanced maternal age and possible abnormalities
associated with severe male infertility. Despite education on these risks,
71% of couples had no interest in receiving formal genetic counselling.
Only 14% of couples at risk would consider using a gamete donor to avoid
transmitting a genetic disorder to a child. The triple test to screen for
fetal abnormalities was acceptable to 82% of couples, but only 47% planned
to have amniocentesis or chorionic villi sampling. Couples were
significantly more likely to opt for prenatal testing if they would
consider terminating a pregnancy should the fetus have a severe genetic
abnormality (P < 0.01). Roman Catholic couples tended to have more
conservative attitudes about pregnancy termination. Socio-economic status
and whether the infertility factor was male or female were not predictors
of a couple's attitudes.
相似文献
9.