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991.
B. Bogin P. Smith A.B. Orden M.I. Varela Silva J. Loucky 《American journal of human biology》2002,14(6):753-761
Maya families from Guatemala migrated to the United States in record numbers from the late 1970s to the early 1990s. Births to Maya immigrant women have created a sizable number of Maya American children. The height and sitting height of 5 to 12 years children (n = 431) were measured in 1999 and 2000. Leg length was estimated and the sitting height ratio was calculated. These data were compared with a sample of Maya children living in Guatemala measured in 1998 (n = 1,347). Maya American children are currently 11.54 cm taller and 6.83 cm longer‐legged, on average, than Maya children living in Guatemala. Consequently, the Maya Americans have a significantly lower average sitting height ratio (i.e., relatively longer legs in proportion to length of the head and trunk) than do the Maya in Guatemala. These results add support to the hypothesis that both the height and body proportions of human populations are sensitive indicators of the quality of the environment for growth. Am. J. Hum. Biol. 14:753–761, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
992.
The T-cell receptor (TCR) repertoire plays an important role in shaping specific immune responses. Genetic polymorphisms at the TCR locus, in both constant and variable regions, seem to represent an important mechanism for generating inter-individual and inter-population differences. Considering the scarcity of immune parameters characterized for normal human populations, we decided to determine the frequency of two TCRBV polymorphisms (located in the TCRBV3S1 and TCRBV18 gene segments) in two ethnically distinct groups of the general Brazilian population. Both polymorphisms are related to the expression of these segments at the T-cell surface and can consequently modulate the T-cell repertoire, potentially modifying the capacity of a given individual to develop an immune response. These DNA polymorphisms were analysed in material obtained from adult, normal South-American Caucasoid and Black individuals. A total of 139 individuals were analysed for the TCRBV3S1 and 141 for the TCRBV18 gene segment polymorphisms. The data indicated statistically significant differences in allelic frequencies for the two ethnic groups analysed, suggesting that any correlation between TCR usage or T-cell repertoire and development of a given disease should take in account the ethnic origin of the population studied. 相似文献
993.
994.
Prevention of Bone Loss by Clodronate in Early Postmenopausal Women with Vertebral Osteopenia: A Dose-Finding Study 总被引:1,自引:0,他引:1
M. J. V?lim?ki K. Laitinen K. Laitinen A. Patronen H. Puolijoki H. Puolijoki J. Sepp?nen L. Pylkk?nenand the Probone Study Group 《Osteoporosis international》2002,13(12):937-947
This double-masked, placebo-controlled study was undertaken to determine the efficacy and safety of oral clodronate in the
prevention of bone loss in early postmenopausal women with vertebral osteopenia. Altogether 610 women with a mean age of 53
years were recruited for the study. They were 1–5 years postmenopausal and their lumbar spine bone mineral density (BMD) was
at least 1 standard deviation below the mean of premenopausal women (T-score ≤−1). The subjects were randomized into five study groups to receive either placebo, clodronate 65 mg, 400 mg or 800
mg daily, or intermittent clodronate in 3 month cycles with 400 mg daily for 15 days followed with no treatment for 75 days
for 3 years. One hundred and eighty-seven of 509 women who completed the primary study continued in the extension study of
2 years in which previous placebo users were switched to clodronate 800 mg daily, while previous users of 400 mg or 800 mg
of clodronate used either placebo or 800 mg of clodronate daily. In the primary study clodronate was administered in the evening,
and in the extension 1 h before breakfast on an empty stomach. In the primary study mean changes in lumbar spine BMD were
−3.4% in the placebo group and +0.4% in 800 mg clodronate group [difference between groups at 3 years 3.8% (95% CI 2.7% to
4.9%, p<0.0001)], and in the trochanter area BMD −1.1% in the placebo group, and + 0.4% in the 800 mg clodronate group [difference
between groups at 3 years 1.5% (95% CI 0.05% to 2.9%)]. During the extension study mean changes in lumbar spine BMD were +1.5%
in the clodronate group and −0.2 % in the placebo group [difference between groups 1.7% (CI 0.4% to 3.0%, p = 0.010)] and in trochanter BMD were +2.5% in the clodronate group and no change in the placebo group [difference between
groups 2.1% (CI 0.3% to 3.9%, p = 0.007)]. No statistically significant differences between the placebo and 800 mg clodronate groups were found in the femoral
neck BMD. In the primary study the urinary excretion of type I collagen aminoterminal telopeptide (NTX) decreased by 44% (p<0.0001 compared with placebo) and that of deoxypyridinoline by 18% (p<0.0001) in the clodronate 800 mg group. In the extension study urinary NTX decreased by 51% (p<0.0001) in those who were switched to 800 mg of clodronate and increased by 67% (p<0.0001) in those who stopped using that dose. There was no difference in the frequency of gastrointestinal complaints between
clodronate- and placebo-treated patients in the primary study, but they were more common among women who received clodronate
in the extension phase. Clodronate in daily doses of 400–800 mg caused a slight elevation of aminotransferase levels, usually
within the reference range. In bone biopsies no defect in mineralization was found. In conclusion, clodronate in a daily dose
of 800 mg prevents early postmenopausal bone loss at the sites of the skeleton in which cancellous bone predominates. It effectively
reduces bone resorption and bone turnover rate. Antifracture efficacy of clodronate remains to be established by prospective,
placebo-controlled trials.
Received: 4 March 2002 / Accepted: 9 July 2002 相似文献
995.
Abra R. M. Hunt C. Anthony Fu K. K. Peters J. H. 《Cancer chemotherapy and pharmacology》1983,11(2):98-101
Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst... 相似文献
996.
997.
998.
Summary In cases where a reconstruction of defects in the larynx, oral cavity, the pharynx or in the ear region has been performed using skin flaps, a temporary fistula is formed at the point of entry.This fistula can be closed later after the flap has taken and the flap pedicle dissected.We would like to demonstrate with some examples that with the use of deepithelisation it is possible to achieve a primary wound closure. This way no temporary fistula results and additional surgery is avoided in many cases.Furthermore flap deepithelisation offers a way to bring good vascularised tissue under the skin and cover subcutaneous defects, for example those after radiotherapy.
Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen 相似文献
Die Veröffentlichung des Manuskripts soll in Laryngol Rhinol Otol (Stuttg) erfolgen 相似文献
999.
C Imperiale 《Journal of clinical engineering》1983,8(3):235-241
The purpose of this project was to design an efficient, low cost, and portable system for renography suitable for clinical use. The principles involved in the renographic test, and the procedures and calculations which act on the design of our system, are given. The system consists of an Apple II Plus computer equipped with 48K memory, two disk drives with diskettes of 143K each, a thermal printer with graphic capability, the Microsoft Z80 card, and an interface which is specifically designed for renographic data acquisition. 相似文献
1000.
HLA-DR typing in identical twins with insulin-dependent diabetes: difference between concordant and discordant pairs 总被引:3,自引:0,他引:3
C Johnston D A Pyke A G Cudworth E Wolf 《British medical journal (Clinical research ed.)》1983,286(6361):253-255
A total of 106 pairs of identical twins, of whom 56 were concordant and 50 discordant for insulin-dependent diabetes, were typed for HLA-DR. In both the concordant and discordant groups there was a high prevalence of the antigens DR3 and DR4, a low prevalence of DR5 and DR7, and a virtual absence of DR2. The heterozygous phenotype DR3,DR4 was more prevalent in concordant than discordant pairs. This was therefore the first demonstration of a genetic difference between concordant and discordant identical twin pairs. These findings suggest that possession of both DR3 and DR4 antigens confers a greater genetic predisposition to insulin-dependent diabetes than does the possession of either antigen alone. 相似文献