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排序方式: 共有1397条查询结果,搜索用时 953 毫秒
991.
Nicolai Bonne Phillip Clark Patrick Shearer Margaret Sharp Shane Raidal 《Comparative clinical pathology》2009,18(4):353-359
The hematological characteristics of juvenile long-billed corellas (Cacatua tenurostris), with or without prior administration of a psittacine beak and feather disease vaccine, were studied for 97 days after experimental
infection with beak and feather disease virus (BFDV). It was found that the pre-challenge hematological values were similar
between vaccinated and non-vaccinated corellas. Most pre-challenge parameters were comparable to previously reported values
of other cockatoos and psittacine birds. Significant differences were seen in both groups when comparing pre-challenge values
with post-challenge values for total and differential leukocyte concentrations, but packed cell volume and total serum protein
were not significantly affected by BFDV challenge. 相似文献
992.
993.
994.
L Pace A Cuocolo A Nappi E Nicolai B Trimarco M Salvatore 《European journal of nuclear medicine》1992,19(9):800-806
The accuracy and repeatability of a new ambulatory radionuclide detector (VEST) for left ventricular systolic (ejection fraction) and diastolic (peak filling rate) measurements were assessed. Seventeen patients underwent equilibrium radionuclide angiography immediately before and immediately after a VEST study. The accuracy was evaluated at the beginning and at the end of the VEST studies. Limits of agreement for the ejection fraction were -1%:2% at the beginning of the VEST study and -4%:4% at the end. Limits of agreement for the peak filling rate were -0.6:0.6 at the beginning of the VEST study and -0.7:0.5 at the end. For both measurements the limits of agreement were well within the clinical range. Repeatability was evaluated in a second group of 11 patients who underwent VEST studies in 2 separate days. The coefficient of repeatability (twice the standard deviation of the differences between the 2 studies) was 13 for the ejection fraction and 0.4 for the peak filling rate. Thus, the VEST is an accurate and repeatable method to measure both the ejection fraction and peak filling rate. 相似文献
995.
Novel water-soluble derivatives of cellulose, amylose and dextran are synthesized and investigated with regard to their special interactions with the anionic surfactant sodium dodecylsulfate (SDS) by means of rheological flow- and oscillatory measurements as well as electrolytic conductivity in aqueous solution. The derivatives of amylose and dextran show a continuous adsorption of SDS with increasing surfactant concentration leading to an increase of the viscosity and of the viscous part of the shear modulus of the solution. Only low elastic parts are detectable. In contrast, the behaviour of cellulose derivatives differs extremely with increasing amount of SDS. The viscosity and the elastic part of the shear modulus of aqueous solutions reach a well pronounced maximum and then drop almost to the initial values. A similar behaviour is also observed by adding the cationic surfactant hexadecyltrimethylammonium bromide. It is concluded that the observed differences in properties of the cellulose derivatives on the one side and derivatives of amylose and dextran on the other are cause by the structure of the polymer main chain, because the side groups for all of these polymers are comparable. 相似文献
996.
We present a case of sphenoid mucocele with large invasion of the middle cranial fossa, secondary to a nasopharyngeal acinic cell carcinoma, occurring in a 52-year-old man. To the best of our knowledge, this association has not been reported so far. We discuss the importance of imaging techniques in delineating the relationship between the two lesions, as long as the clinical and therapeutic problems related both to sphenoid mucocele and acinic cell carcinoma. 相似文献
997.
998.
Hovind P Tarnow L Rossing K Rossing P Eising S Larsen N Binder C Parving HH 《Diabetes care》2003,26(4):1258-1264
OBJECTIVE: Conflicting evidence of a decline in incidence of microvascular complications in type 1 diabetes during the last decades has been reported. To assess recent trends in the cumulative incidence of diabetic microangiopathy in type 1 diabetes, we analyzed data from long-term prospective observational studies lasting >/=20 years. RESEARCH DESIGN AND METHODS: A total of 600 Caucasian patients with onset of type 1 diabetes between 1965 and 1984 were followed until death or until the year 2000. Patients were divided into four groups based on the year of diabetes onset: group A, 1965-1969 (n = 113); group B, 1970-1974 (n = 130); group C, 1975-1979 (n = 113); and group D, 1979-1984 (n = 244). Group A, B, and C are prevalence cohorts identified in 1984; group D is an inception cohort. RESULTS: In patients followed for >/=20 years, the cumulative incidence (95% CI) of diabetic nephropathy after 20 years of diabetes (urinary albumin excretion >300 mg/24 h) was reduced in patients with more recent diabetes onset (groups A-D): 31.1% (22.5-39.7) vs. 28.4% (19.8-37.0) vs. 18.9% (10.9-26.9) vs. 13.7% (6.2-21.2) (P = 0.015). Similarly, the cumulative incidence of proliferative retinopathy was as follows: 31.2% (22.2-39.8) vs. 30.3% (22.2-38.4) vs. 19.3% (11.2-27.4) vs. 12.5% (5.2-19.8) (P < 0.01). In the latter groups, antihypertensive treatment was started earlier, blood pressure and HbA(1c) were lower, and fewer patients smoked. CONCLUSIONS: Our study demonstrates a decrease in the cumulative incidence of diabetic microangiopathy in type 1 diabetes over the past 35 years. Improved glycemic control, lower blood pressure (in part due to early aggressive antihypertensive treatment), and reduced prevalence of smoking rates were associated with the improved prognosis. 相似文献
999.
A new phospholipid phosphatase,PRG-1, is involved in axon growth and regenerative sprouting 总被引:1,自引:0,他引:1
Outgrowth of axons in the central nervous system is governed by specific molecular cues. Molecules detected so far act as ligands that bind to specific receptors. Here, we report a new membrane-associated lipid phosphate phosphatase that we have named plasticity-related gene 1 (PRG-1), which facilitates axonal outgrowth during development and regenerative sprouting. PRG-1 is specifically expressed in neurons and is located in the membranes of outgrowing axons. There, it acts as an ecto-enzyme and attenuates phospholipid-induced axon collapse in neurons and facilitates outgrowth in the hippocampus. Thus, we propose a novel mechanism by which axons are able to control phospholipid-mediated signaling and overcome the growth-inhibiting, phospholipid-rich environment of the extracellular space. 相似文献
1000.
Doliba NM Vatamaniuk MZ Buettger CW Qin W Collins HW Wehrli SL Carr RD Matschinsky FM 《Diabetes》2003,52(2):394-402
In the present study, noninvasive (31)P and (23)Na(+)-nuclear magnetic resonance (NMR) technology and respirometry were used to compare the effect of high glucose (30 mmol/l) with the effect of the antidiabetic sulfonylurea (SU) compound glyburide (GLY) on energy metabolism, Na(+) flux, insulin, and cAMP release of continuously superfused beta-HC9 cells encapsulated in microscopic agarose beads. Both high glucose and GLY increased oxygen consumption in beta-HC9 cells (15-30%) with a maximal effect at 8 mmol/l for glucose and at 250 nmol/l for GLY. At the same time, insulin release from beta-cells increased by 15- and 25-fold with high glucose or GLY, respectively. The P-creatine (PCr) level was greatly increased and inorganic phosphate (P(i)) was decreased with 30 mmol/l glucose in contrast to the decreased level of PCr and increased P(i) with GLY. ATP levels remained unchanged during both interventions. Studies on isolated mitochondria of beta-HC9 cells showed that GLY added to mitochondria oxidizing glutamine or glutamate abolished the stimulation of respiration by ADP (state 3) meanwhile leaving state 3 respiration unchanged during oxidation of other substrates. Exposure of beta-HC9 cells to 5 mmol/l glucose decreased intracellular Na(+) levels monitored by (23)Na(+)-NMR spectroscopy and 30 mmol/l glucose resulted in a further decrease in cytosolic Na(+). In contrast, Na(+) increased when 1 micro mol/l GLY was added to the perfusate containing 5 mmol/l glucose. These data support the hypothesis that glucose activates the beta-cell through a "push mechanism" due to substrate pressure enhancing fuel flux, energy production, and extrusion of Na(+) from the cells in contrast to SU receptor (SUR)-1 inhibitors, which may modify intermediary and energy metabolism secondarily through a "pull mechanism" due to higher energy demand resulting from increased ion fluxes and the exocytotic work load. 相似文献