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101.
Sutada Lotinun Glenda L Evans James T Bronk Mark E Bolander Thomas J Wronski Erik L Ritman Russell T Turner 《Journal of bone and mineral research》2004,19(7):1165-1171
We examined the time course effects of continuous PTH on cortical bone and mechanical properties. PTH increased cortical bone turnover and induced intracortical porosity with no deleterious effect on bone strength. Withdrawal of PTH increased maximum torque to failure and stiffness with no change in energy absorbed. INTRODUCTION: The skeletal response of cortical bone to parathyroid hormone (PTH) is complex and species dependent. Intermittent administration of PTH to rats increases periosteal and endocortical bone formation but has no known effects on intracortical bone turnover. The effects of continuous PTH on cortical bone are not clearly established. MATERIALS AND METHODS: Eighty-four 6-month-old female Sprague-Dawley rats were divided into three control, six PTH, and two PTH withdrawal (WD) groups. They were subcutaneously implanted with osmotic pumps loaded with vehicle or 40 microg/kg BW/day human PTH(1-34) for 1, 3, 5, 7, 14, and 28 days. After 7 days, PTH was withdrawn from two groups of animals for 7 (7d-PTH/7d-WD) and 21 days (7d-PTH/21d-WD). Histomorphometry was performed on periosteal and endocortical surfaces of the tibial diaphysis in all groups. microCT of tibias and mechanical testing by torsion of femora were performed on 28d-PTH and 7d-PTH/21d-WD animals. RESULTS AND CONCLUSIONS: Continuous PTH increased periosteal and endocortical bone formation, endocortical osteoclast perimeter, and cortical porosity in a time-dependent manner, but did not change the mechanical properties of the femur, possibly because of addition of new bone onto periosteal and endocortical surfaces. Additionally, withdrawal of PTH restored normal cortical porosity and increased maximum torque to failure and stiffness. We conclude that continuous administration of PTH increased cortical porosity in rats without having a detrimental effect on bone mechanical properties. 相似文献
102.
103.
Herman M van Praag 《The world journal of biological psychiatry》2004,5(3):155-160
Stress often precedes psychiatric disorders. This holds particularly for the group of mood disorders. A crucial question is whether stress is an epiphenomenon or a decisive factor in the causation of (certain forms of) mood disorder. Certainty about this question can only be obtained when it can be demonstrated that stress phenomena may induce changes in brain functioning similar to the ones supposedly associated with (certain forms of) depression. Since the phenomenology of stress syndromes, as well as their emotional intensity, are highly variable, careful diagnosis is a first requirement. In studies into the significance of stress in the occurrence of depression this degree of finesse has not been achieved. The major shortcomings are discussed. Those should be systematically addressed to provide this type of research with the necessary acuity 相似文献
104.
105.
L L Habets J Bras H P van den Akker A M Borgmeyer-Hoelen C P van Ooij 《International journal of oral and maxillofacial surgery》1987,16(5):540-547
92 patients, 31 with and 61 without signs of metabolic bone loss, were treated with a combined sandwich-visor osteotomy. A 5-year follow-up showed a significantly higher rate of resorption in patients with radiographic signs of metabolic bone loss. The analysis was based upon lateral cephalometry. 相似文献
106.
Serum prolactins in the diagnosis of epilepsy: sensitivity, specificity, and predictive value 总被引:8,自引:0,他引:8
Serum prolactin levels rise after generalized tonic-clonic and partial complex seizures, but not after pseudoepileptic seizures. The criteria for a significant elevation in serum prolactin vary with individual investigators. The prevalence of pseudoseizures in the population studied determines the predictive value of serum prolactin determinations. In populations where most patients have epilepsy, a rise in serum prolactin is highly predictive for true epilepsy, but no increase in serum prolactin is not predictive for pseudoseizures. 相似文献
107.
108.
An elderly female alcohol and benzodiazepine addict presented with an atypical amnestic episode. Five days later she showed several complex partial seizures as main signs of a withdrawal state. The value of the EEG in the differential diagnosis of amnestic syndromes is emphasized. Temporolimbic involvement in withdrawal states is discussed and our ignorance regarding drug dependence and withdrawal in the elderly is stressed. It is suggested that late-onset partial seizures with unknown etiology in the elderly might be more often related to drug dependence than generally accepted. 相似文献
109.
Pharmacokinetics and hemodynamic effects of long-term nisoldipine treatment in hypertensive patients
J van Harten P van Brummelen M Danhof R P Quekel D D Breimer 《Journal of cardiovascular pharmacology》1989,13(4):624-629
In six patients with essential hypertension, the pharmacokinetics of nisoldipine were investigated before, during, and after 4 weeks of treatment. On day 1, nisoldipine was infused intravenously (i.v. 2 mg in 2 h); on day 2, oral nisoldipine treatment (10-mg tablets twice daily) was started for 4 weeks. During this period, patients came to the hospital six times, on which occasions blood samples were taken for the determination of trough and peak concentrations of nisoldipine. After 4-week treatment, the infusion experiment was repeated. In the first infusion experiment, systemic clearance was 1.02 +/- 0.23 L/min (mean +/- SD), terminal half-life (t1/2) was 15.4 +/- 6.7 h, and volume of distribution was 5.9 +/- 1.8 L/kg. After 4 weeks, these parameters had not changed significantly. Nisoldipine lowered blood pressure (BP) in all patients, whereas forearm blood flow and heart rate (HR) increased. Neither were the hemodynamic changes different after the oral treatment period, although basal BP was lower than before oral treatment. No accumulation of nisoldipine occurred during the 4-weeks treatment period. 相似文献
110.
António Travassos Susana Teixeira Pinto Ferreira Isaura Regadas Ana Sofia Travassos Florindo Esteves Esperancinha Isabel Prieto Grapa Pires Robert van Velze A Valido Maria do Céu Machado 《Ophthalmic surgery, lasers & imaging》2007,38(3):233-237
The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months 相似文献