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101.
Dorthe Hartwell Bente Juel Riis Claus Christiansen 《Calcified tissue international》1990,47(6):332-337
Summary We studied 20 healthy premenopausal women aged 36.5±4.0 years (mean±1 SD), 123 healthy postmenopausal women aged 50.0±2.4
years, and 103 postmenopausal women aged 65.1±5.6 years with symptomatic osteoporosis (forearm and spinal fracture). Serum
levels of vitamin D metabolites [25(OH)D, 24,25(OH)2D3, and 1,25(OH)2D] were compared with (1) bone mass in the forearm (single photon absorptiometry) and in the spine (dual photon absorptiometry);
(2) biochemical indices of bone formation (serum alkaline phosphatase, plasma bone Gla protien), and bone resorption (fasting
urinary hydroxyproline); and (3) other biochemical estimates of calcium metabolism (serum calcium, serum phosphate, 24-hour
urinary calcium, intestinal absorption of calcium). The present study revealed no difference in any of the vitamin D metabolites
between the premenopausal women, the healthy postmenopausal women and the osteoporotic women as a group. The concentrations
of 1,25(OH)2D and 25(OH)D were significantly lower in patients with spinal fracture than in those with forearm fracture. In the early
postmenopausal women, serum 1,25(OH)2D was related to forearm bone mass (r=−0.20;P<0.05), intestinal calcium absorption (r=0.18;P<0.05), and 24-hour urinary calcium (r=0.21;P<0.05); serum 25(OH)D was related to spinal bone mass (r=0.23;P<0.01). In the osteoporotic women, serum vitamin D metabolites were not related to bone mass, but 1,25(OH)2D was related to bone Gla protein (r=0.33;P<0.001), serum phosphate (r=−0.27;P<0.01), and 24-hour urinary calcium (r=0.43;P<0.001). The present study demonstrates that in a population that is apparently not deficient in vitamin D, a disturbance
of the vitamin D metabolism is not likely to play a pathogenetic role in early postmenopausal bone loss. Patients with spinal
fractures have low levels of vitamin D metabolites, which may aggravate their osteoporosis. 相似文献
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vanSonnenberg E; Casola G; Zakko SF; Varney RR; Cox J; Wittich GR; Hofmann AF 《Radiology》1988,169(2):505-509
The authors describe percutaneous treatment of gallbladder or bile duct stones in 18 patients who were poor surgical candidates or in whom conventional therapy failed. Dissolution was performed in most cases with methyl tert-butyl ether (MTBE) because of its potent dissolution properties; other solvents used included monooctanoin or chelating solutions. Gallbladder stones were eliminated in 11 of 13 patients (six of seven with dissolution alone, four of four with dissolution and basket extraction, one with basket removal alone). In five patients with stones in the common bile duct (n = 3), cystic duct remnant (n = 1), and intrahepatic bile ducts (n = 1), stones were eliminated with dissolution alone in two and with dissolution plus basket extraction in one. In two patients percutaneous therapy failed due to complications (vagal hypotension with bile peritonitis and transient respiratory arrest) that occurred during catheter placement. Preliminary results suggest that MTBE is effective for dissolution of many gallbladder stones and some bile duct stones. Noncholesterol solvents and adjuvant mechanical maneuvers are valuable adjuncts to achieve complete stone elimination. 相似文献
105.
A prospective study of the renal abnormalities on excretion urography in 189 patients with homozygous sickle cell disease is presented. Demonstrable abnormalities were present in 69% but there was no correlation with symptomatology. Calyceal clubbing was the most common abnormality occurring in 39% of cases and its incidence increased with age. An unexpectedly high prevalence (23%) of papillary necrosis occurred and both sinuses and cavities were demonstrated. The reasons for this high prevalence are discussed. The urographic findings did not correlate significantly with hematological features of the disease. 相似文献
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The role of estrogen in pubertal skeletal physiology: epiphyseal maturation and mineralization of the skeleton 总被引:1,自引:0,他引:1
GR Frank 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(6):627-630
The year 1994 is likely to be remembered by many endocrinologists as the year in which dramatic new light was shed on the role played by estrogen in human skeletal physiology. It was in 1994 that two new syndromes were described, each representing a human model in which estrogen action was lacking. The first case was a female with an aromatase defect and a resultant inability to synthesize estrogen, and the second case was a man with an estrogen receptor gene defect that resulted in a non-functioning estrogen receptor and complete estrogen resistance. By examining the phenotypes of these two individuals, we were able, for the first time, to see what pubertal skeletal changes occur in the absence of estrogen action and directly extrapolate the role of estrogen in skeletal physiology. What has become abundantly clear is that it is estrogen and not androgen that is responsible for pubertal epiphyseal maturation and skeletal mineralization 相似文献