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141.
To evaluate the relative contribution of insulin binding and postbinding defects of glucose utilization in peripheral tissue during normal and diabetic pregnancy, we have studied the in vitro insulin action of isolated adipocytes from eight nondiabetic pregnant women and nine pregnant women with insulin-dependent diabetes mellitus who were undergoing cesarian section. The pregnant women were compared with a matched group of normal nonpregnant women undergoing gynecologic surgery. Insulin binding to adipocytes measured at tracer insulin concentration was reduced by 45% (P less than 0.01) in normal pregnant women and by 30% (P less than 0.02) in pregnant women with diabetes. In contrast, no changes were found between the three groups in insulin binding to pure monocytes and erythrocytes. The glucose transport system in fat cells from both groups of pregnant women was characterized by impaired maximal (P less than 0.05) and half-maximal (P less than 0.05) response to insulin. When fat cell glucose metabolism was studied, pregnant diabetic women exhibited decreased basal lipogenesis (P less than 0.05) and decreased maximal responses of lipogenesis and glucose oxidation to insulin stimulation (P less than 0.05). Similar but less pronounced abnormalities were seen in glucose metabolism of adipocytes from nondiabetic pregnant women. In conclusion, both in late normal and diabetic pregnancy, insulin binding to adipocytes is significantly reduced and accompanied by decreased insulin sensitivity and reduced maximal insulin responsiveness of glucose transport and by impaired basal and maximally insulin-stimulated glucose metabolism. 相似文献
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N Nelson O Finnstr?m L Larsson 《Scandinavian journal of clinical and laboratory investigation》1987,47(2):111-117
Thirty-one full-term newborn babies were investigated in order to establish reference values for ionized calcium. Only children fulfilling certain optimality criteria (with best possible maternal and infant conditions and uncomplicated pregnancy and delivery) were included. All infants were breast fed. Capillary blood for analysis of ionized calcium was collected by heel puncture on day 1 (6-36 h post partum, p.p.), day 3 (60-84 h p.p.) and day 5 (108-132 h p.p.). Ionized calcium was measured with a semi-automatic electrode system ICA 1 (Radiometer A/S, Copenhagen, Denmark). The reference ranges (mean +/- 2 SD) for days 1, 3 and 5 were 1.05-1.37, 1.10-1.42 and 1.20-1.48 mmol/l, respectively. The mean ionized calcium concentration on day 1 was significantly lower than on days 3 and 5. Reference values are also given for total calcium, magnesium and phosphate. We emphasize that it is impossible to calculate ionized calcium from total calcium or vice versa. 相似文献
147.
P Helwig G Faust U Hindenlang B Kr?plin C Eingartner 《Technology and health care》2006,14(4-5):411-419
Static analysis with finite element of a realistic femur nail bone-implant system in a typical proximal femoral fracture under physiological load bearing situations provides results for stress, displacement and strain. The question to be answered is, if simulation with the finite element analysis is able to explain biomechanically clinical observed patterns of failure. Surface-Reconstruction with CT database of a proximal femur and reconstruction with CT based density data was done. Next steps were to unite the bone structure with the Proximal Femoral Nail and to model two relevant fractures (31-A2.2 and A2.3 according AO). After modelling of geometry, isotropic material behaviour and load application numeric calculation of the femur-nail system with FE-software was performed. FE simulation mainly shows an axial dislocation of the femoral head screw with nearly no dislocation of the antirotation screw. This so-called z-effect therefore means: (1) Tilting of the proximal main fragment around the sagittal axis between the screws and (2) relative movement of both screws in the frontal plane. Relative movement of the two screws against each other could be the reason for implant failure, the so called cut out. Furthermore simulation shows different gliding of the screws explaining the so called z-telescoping. The analyzed stress patterns have to be relativized, because isotropic material behaviour of cancellous bone was assumed. Further examinations for this issue are necessary. 相似文献
148.
OBJECTIVE: This review examines acute and chronic whiplash-associated disorders to facilitate assessment, treatment and rehabilitation for further research and evidence-based practices. DESIGN: A review of the literature. RESULTS AND CONCLUSION: Whiplash-associated disorders account for a large proportion of the overall impairment and disability caused by traffic injuries. Rarely can a definite injury be determined in the acute (or chronic) phase. Crash-related factors have been identified, and several trauma mechanisms possibly causing different injuries have been described. Most whiplash trauma will not cause injury, and the majority of patients (92-95%) will return to work. Litigation is not a major factor. Cognitive impairments are not the same as brain injury. Variables such as pain intensity, restricted motion, neurological symptoms and signs, together with central nervous system symptoms can be used to predict a situation with risk of remaining complaints. Influences of other factors--the same as for other chronic pain conditions--also exist. Persistent/chronic pain is not merely acute pain that persists over time; changes occur at different levels of the pain transmission system. Chronic whiplash-associated disorders are associated with problems concerning social functioning, daily anxieties and satisfaction with different aspects of life. Adequate information, advice and pain medication together with active interventions might be more effective in the acute stage. Early multidisciplinary rehabilitation focusing on cognitive-behavioural changes might be of value. To develop specific treatment and rehabilitation, it is important to identify homogenous subgroups. 相似文献
149.
S Lombardi Borgia M Regehly R Sivaramakrishnan W Mehnert H C Korting K Danker B R?der K D Kramer M Sch?fer-Korting 《Journal of controlled release》2005,110(1):151-163
With topical treatment of skin diseases, the requirement of a high and reproducible drug uptake often still is not met. Moreover, drug targeting to specific skin strata may improve the use of agents which are prone to cause local unwanted effects. Recent investigations have indicated that improved uptake and skin targeting may become feasible by means of nanoparticular systems such as solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC) and nanoemulsions (NE). Here we describe techniques to characterize drug loading to carrier systems and skin penetration profiles by using the lipophilic dye nile red as a model agent. Since the mode of drug association with the particle matrix may strongly influence the efficiency of skin targeting, parelectric spectroscopy (PS) was used to differentiate between matrix incorporation and attachment to the particle surface and fluorescence spectroscopy (FS) to solve dye distribution within NLC particles. Nile red was incorporated into the lipid matrix or the covering tensed shell, respectively, of SLN and NLC with all the lipids studied (Compritol, Precirol, oleic acid, Miglyol). In NLC, the dye was enriched in the liquid phase. Next, nile red concentrations were followed by image analysis of vertical sections of pigskin treated with dye-loaded nanoparticular dispersions and an oil-in-water cream for 4 and 8 h in vitro. Following the SLN dispersions, dye penetration increased about fourfold over the uptake obtained following the cream. NLC turned out less potent (相似文献
150.
Isabella Sch?ll George Boltz-Nitulescu Erika Jensen-Jarolim 《Journal of controlled release》2005,104(1):1-27
For the treatment of infectious diseases, cancer and allergy, the directed induction of an appropriate immune response is the ultimate goal. Therefore, with the development of pure, often very small proteins, peptides or DNA by molecular biology techniques, the research for suitable adjuvants or delivery systems became increasingly important. Particle formulations are made of a variety of materials, including lipids, proteins or amino acids, polysaccharides, polyacrylic substances or organic acids. Microparticles serve as vehicles and provide a depot for the entrapped or coupled antigen. The release occurs in a pulsatile or continuous manner, a feature, which is well controllable for many particulate systems. Particles attract antigen presenting cells to the administration site, thereby guaranteeing the efficient presentation of the antigen to the immune system. Importantly, particles also protect the entrapped substance. This is especially necessary after oral application to avoid gastric or tryptic breakdown. In this article, the design and construction of different antigen delivery systems and their immune effects, with special focus on the suitability for allergy treatment, are discussed. 相似文献