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61.
Serum concentrations of alkaline phosphatase isoenzymes and osteocalcin in normal pregnancy 总被引:4,自引:0,他引:4
A Rodin A Duncan H W Quartero G Pistofidis G Mashiter K Whitaker D Crook J C Stevenson M G Chapman I Fogelman 《The Journal of clinical endocrinology and metabolism》1989,68(6):1123-1127
We measured serum alkaline phosphatase isoenzymes and osteocalcin levels in 40 healthy women at 4-week intervals throughout uncomplicated pregnancies and 6 weeks after delivery in 17 women. Serum bone alkaline phosphatase was significantly higher in the third trimester than in early pregnancy (P less than 0.001), and this elevation was still apparent at the end of the puerperium, suggesting increased bone turnover. Serum osteocalcin was not detected (less than 0.2 micrograms/L) after the first trimester in the majority of women, and it reappeared within 48 h after delivery. The disappearance of osteocalcin after the first trimester and its rapid reappearance after delivery suggest placental clearance of this peptide. We conclude that serum osteocalcin measurements cannot be used as a marker of bone metabolism during pregnancy. 相似文献
62.
Deep brain stimulation for pain control in humans was first used almost 30 years ago and has continued to receive considerable attention. Despite the large number of clinical reports describing pain relief, numerous studies have indicated that the results of these procedures vary considerably. In addition, many neurosurgeons find the procedures unpredictable, and considerable disagreement still exists regarding important issues related to the technique itself. This review gives an historical overview of the relevant basic and clinical literature and provides a critical examination of the clinical efficacy, choice of stimulation sites, parameters of stimulation, and effects on experimental pain. Finally, we give suggestions for future research that could more definitively determine the usefulness of deep brain stimulation for pain control. 相似文献
63.
Regional extraction of circulating norepinephrine, DOPA, and dihydroxyphenylglycol in humans 总被引:1,自引:0,他引:1
D S Goldstein R O Cannon A Quyyumi P Chang M Duncan J E Brush G Eisenhofer 《Journal of the autonomic nervous system》1991,34(1):17-35
Dihydroxyphenylglycol (DHPG) is the main intraneuronal metabolite of the sympathetic neurotransmitter, norepinephrine (NE), and dihydroxyphenylalanine (DOPA) the immediate product of the rate-limiting step in catecholamine biosynthesis. Simultaneous measurements of regional rates of appearance (spillovers) of NE, DOPA, and DHPG in plasma have the potential to provide unique information about aspects of sympathoneural function but have not actually been measured in humans. In the present study, spillovers of DHPG, DOPA, and NE in the heart, head, leg, and lungs, were estimated from regional extraction fractions of infused [3H]-1-NE, DHPG, and [13C6]DOPA or unlabelled DOPA in humans during cardiac catheterization. There was little cardiac extraction of DHPG (7 +/- SEM 2%) or DOPA (8 +/- 4%) but substantial extraction of NE (69 +/- 4%). Values for cardiac spillover of DHPG and DOPA therefore were similar to values for the arteriovenous increment times plasma flow (arteriovenous production rate), whereas the cardiac spillover of NE averaged about 7-times the NE arteriovenous production rate. Cardiac DHPG spillover (28 +/- 3 ng/min) exceeded the spillovers of NE (9 +/- 2 ng/min) and DOPA (15 +/- 4 ng/min). In contrast, cranial DOPA spillover (159 ng/min) exceeded those of NE and DHPG by 8- and 2-fold and accounted for about 1/10 of the total spillover of DOPA into arterial plasma. In the femoral vascular bed, arteriovenous production rates of NE and DHPG were unrelated to femoral spillovers of NE and DHPG. Arterial and regional clearances of [13C6]DOPA were similar to those of unlabelled DOPA. The results suggest that (1) endogenous NE, DOPA, and DHPG all are released into the bloodstream by the heart, head, and limbs of humans; (2) DHPG and DOPA are not co-released with NE; (3) cardiac arteriovenous production rates of DOPA and DHPG can be used to indicate cardiac spillover of these catechols, whereas the cardiac NE arteriovenous production rate substantially underestimates cardiac NE spillover; and (4) estimates of limb spillover of NE and DHPG require concurrent measurements of the corresponding regional clearances. 相似文献
64.
65.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Anton Serafini M.D. Robert C. Duncan Ph.D. M. Judith Donovan Post M.D. Berta M. Montalvo M.D. Jose I. Becerra M.D. 《Emergency radiology》1997,4(4):191-199
The purpose of this study was to evaluate the ability of helical computed tomography (CT) to detect arterial injuries in gunshot wounds to the neck. In a blinded retrospective review, 54 helical CT scans of the cervical spine were evaluated for bullet/bone fragments, subcutaneous air, bullet path, hematoma, spine fractures, and pharyngoesophageal compromise. The distance of fragments to a major vessel was calculated. CT findings that correlated significantly with major arterial injury included the presence of fragments (bullet/bone) close to a major vessel (2.5 mm) and spine fractures. Visualizing fragments <5 mm from a vessel or a transcervical bullet trajectory predicted 12 of 13 major arterial injuries. We conclude that CT clearly depicts anatomic damage. Specific findings, such as the location of fragments and bullet trajectory adjacent to a vessel and spine fractures, indicate a higher probability of vascular damage, thus directing more definitive evaluation. 相似文献
66.
Colour Doppler flow imaging (CD) is a well-established method of assessing valvular and congenital disease of the heart. The technique has proven useful intraoperatively in patients undergoing valve repair or replacement or intracardiac reconstruction. In 21 patients with various cardiac anomalies, colour Doppler flow imaging was used intraoperatively, before cardiac cannulation and again after cardiopulmonary bypass. Previously undisclosed features were demonstrated preoperatively in two patients and important residual defects after cardiopulmonary bypass in three others. Adequacy of valve replacement was confirmed in four patients and small leaks in ventricular septal defect patches were shown in another three. The procedure facilitated repair of complex cardiac fistulas in two patients. There were no apparent complications from CD. As intracardiac repairs become more complex, the role of intraoperative CD will expand. 相似文献
67.
68.
A 3-year-old boy, who developed the signs and symptoms characteristic of Kawasaki disease, is described. The child also had an 8 cm tender hepatomegaly. Hydrops of the gallbladder could not be shown. Liver biopsy showed marked infiltration of inflammatory cells, including neutrophil and eosinophil leucocytes in the portal tracts involving the periphery of the portal arteries and veins, and acute inflammation of the bile ducts with neutrophil and eosinophil infiltration of the walls. Overt cholangitis has been described only once before in Kawasaki disease, when a viral agent was suggested as being important in the pathogenesis. Although the clinical and laboratory findings in cases of Kawasaki disease clearly suggest an acute infection--as they did in this case--no aetiological agent has yet been incriminated. The possibility of a drug-induced auto-allergic or hypersensitivity state is considered. Evidence for such a state includes a history of drug administration, pathological findings similar to peri-arteritis nodosa--a condition often associated with a hypersensitivity state--the presence of eosinophils in the lesions and a response to treatment with aspirin, a drug known to ameliorate hypersensitivity states. 相似文献
69.
70.
G R Smith C Conger D F O'Rourke R W Steele R K Charlton S S Smith 《Psychosomatics》1992,33(4):444-451
Considerable data have demonstrated that psychological states can influence the immune system in animals. Whether human immune function can be intentionally modulated by the central nervous system is unknown. This article presents data from two studies that sought to demonstrate intentional modulation of the immune system by psychological interventions. It also discusses the methodological complexities involved with this type of research in humans. 相似文献