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41.
42.
OBJECTIVE: To investigate the risk factors for osteoporosis among a sample of middle-aged women. METHODS: Adipose tissue and bone mineral density levels at the left femur, lumbar spine, and total body were assessed using dual-energy x-ray absorptiometry (DXA). Subjects (n=342) were surveyed regarding a variety of osteoporosis-related risk factors. Forward stepwise multiple regression procedures were utilized. RESULTS: Menstrual status, hormone replacement therapy, adipose tissue, and dairy product intake were retained in the regression models. CONCLUSIONS: Osteoporosis prevention programs need to emphasize the importance of hormonal status and body composition in addition to obtaining adequate calcium intake. 相似文献
43.
Bleeker MC Hogewoning CJ Voorhorst FJ van den Brule AJ Snijders PJ Starink TM Berkhof J Meijer CJ 《International journal of cancer. Journal international du cancer》2003,107(5):804-810
Penile HPV-associated lesions are frequently seen in male sexual partners of women with CIN. The natural course and clinical significance of these lesions are unclear. Women with CIN and their male sexual partners were randomized for condom use (condom group n = 68, noncondom group n = 68). Males were screened for the presence of penile lesions, i.e., flat lesions, papular lesions and condylomata acuminata, and of HPV in their penile swabs by PCR testing. Median follow-up time was 13.1 months (range 2.9-57.4). The outcome of our study was clinical regression of penile lesions defined as disappearance of lesions at penoscopy. Potentially prognostic factors, i.e., HPV status, lesion type and age, were studied as well. Outcomes were assessed in 57 men of the condom group and in 43 men of the noncondom group. Condom use shortened the median time to regression of flat penile lesions (7.4 months condom group vs. 13.9 months noncondom group; HR = 2.1, 95% CI 1.2-3.7). This effect was not found for papular lesions (HR = 0.5, 95% CI 0.1-2.8). HPV-negative men showed a significantly shorter median time to regression of flat lesions (3.8 months) compared to men with either HPV-positive status (8.5 months; HR = 0.4, 95% CI 0.2-0.9) or inconsistent HPV status (13.1 months; HR = 0.2, 95% CI 0.1-0.6). Regression of flat penile lesions is HPV-dependent and accelerated by condom use. This effect is probably the result of blocking viral transmission between sexual partners. 相似文献
44.
Bos IG van Mierlo GJ Bleeker WK Rigter GM te Velthuis H Dickneite G Hack CE 《International immunopharmacology》2001,1(8):1583-1595
C1-inhibitor (C1-Inh) is an important regulator of inflammatory reactions because it is a potent inhibitor of the contact and complement system. C1-Inh application in inflammatory disease is, however, restricted because of the high doses required. The glycosaminoglycan-like molecule dextran sulphate (DXS) enhances C1-Inh function in vitro. Hence, we investigated whether co-administration with dextran sulphate reduces the amount of C1-Inh required, through enhancement in vivo. C1-Inh potentiation was measured in a newly developed C1s-inactivation assay that is based on activation of C4 by purified C1s. Activated C4 in rat plasma was quantified with a newly developed ELISA. Human C1-Inh (2.5 microM) inhibited C1s in rat plasma 55-fold faster in the presence of dextran sulphate (15 kDa, 5 microM). To study the stability of the complex in vivo, rats were given a mixture of C1-Inh (10 mg/kg) and dextran sulphate (3 mg/kg). C1-Inh activity during 5 h was analyzed ex vivo with the C1s inactivation assay. The noncovalent C1-Inh-dextran sulphate complex resulted in a transient enhancement of the inhibitory capacity of C1-Inh, lasting for 60-90 min. Dextran sulphate did not affect plasma clearance of C1-Inh. We conclude that the enhanced inhibitory capacity of C1-Inh complexed to dextran sulphate is transient in vivo. Hence, co-administration of these compounds seems a feasible approach to achieve short-term inhibition of complement in vivo. 相似文献
45.
Michiel W. P. Bleeker Miriam Kooijman Gerard A. Rongen Maria T. E. Hopman Paul Smits 《The Journal of physiology》2005,565(2):685-694
Deconditioning is a risk factor for cardiovascular disease. Exercise reduces this risk, possibly by improving the vascular endothelial nitric oxide (NO) pathway. The effect of deconditioning on the NO pathway is largely unknown. This study was designed to assess baseline NO availability in the leg vascular bed after extreme, long-term deconditioning (spinal cord-injured individuals, SCI) as well as after moderate, short-term deconditioning (4 weeks of unilateral lower limb suspension, ULLS). For this purpose, seven SCI were compared with seven matched controls. Additionally, seven healthy subjects were studied pre- and post-ULLS. Leg blood flow was measured by venous occlusion plethysmography at baseline and during infusion of 5 incremental dosages of N G -monomethyl- l -arginine ( l -NMMA) into the femoral artery. Sodium nitroprusside (SNP) was infused to test vascular responsiveness to NO. Baseline leg vascular resistance tended to be higher in SCI compared with controls (37 ± 4 versus 31 ± 2 arbitrary units (AU), P = 0.06). Deconditioning altered neither the vasoconstrictor response to l -NMMA (increase in resistance in SCI versus controls: 102 ± 33% versus 69 ± 9%; pre- versus post-ULLS: 95 ± 18% versus 119 ± 15%), nor the vascular responsiveness to NO. In conclusion, two human in vivo models of deconditioning show a preserved baseline NO availability in the leg skeletal muscle vascular bed. 相似文献
46.
SE Andrew 《Clinical genetics》2003,64(4):293-296
47.
PJ Fielder SE Gargosky M Vaccarello K Wilson P Cohen F Diamond J Guevara-Aguirre AL Rosenbloom RG Rosenfeld 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S389):40-43
Six adult patients with growth hormone receptor deficiency (GHRD) (2 men, 4 women) with an identical defect in the growth hormone receptor (GHR) gene, were treated with recombinant human insulin-like growth factor I (IGF-I), 40 μgikg S.C. twice daily, for 7 days. Serum concentrations of IGF peptide and IGF binding protein-3 (IGFBP-3) were measured by specific radioimmunoassays; serum IGFBPs were also measured by Western ligand blotting. The size distribution of both IGF-I and IGF-II was measured in serum following size-exclusion fast-performance liquid chromatography. IGF-I treatment resulted in a normalization of serum IGF-I levels on days 1–7 of treatment and a decrease in serum IGF-II levels. The fall in IGF-II levels and the simultaneous rise in IGF-I levels, however, resulted in an unchanged total serum IGF level. The low IGFBP-3 values did not significantly change during treatment, whereas there was a slight increase in IGFBP-2 levels. Preliminary analysis of size-fractionated sera suggested an increase in IGF-I levels in the 40 and 150 kDa regions at the expense of IGF-II levels. The results suggest that despite the failure of IGF-I treatment to increase IGFBPs significantly, serum IGFBP concentrations were sufficient to maintain normal levels of IGF-I. 0 Laron syndrome, growth hormone receptor deficiency, insulin-like growth factors, insulin-like growth factor binding protein 相似文献
48.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
49.
Kirkpatrick SE; Pitlick PT; Naliboff J; Friedman WF 《The American journal of physiology》1976,231(2):495-500
50.