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81.
82.
Triphasic waves (TWs) can be recorded on EEG in the course of several metabolic disorders, mainly hepatic encephalopathy. A case of acute encephalopathy due to naproxen intoxication is reported, in the course of which diffuse, bilateral and symmetrical TWs were recorded. Biochemical mechanisms that might determine both a complex encephalopathy and TWs are discussed.  相似文献   
83.
A cardiac transplant recipient with multiple coronary artery fistulae draining into the right ventricle is described. These fistulae presumably resulted from repeated endomyocardial biopsies. The diagnosis of coronary artery fistulae was made at the annual coronary arteriography. The magnitude of the shunt remained small over eight years of follow-up.  相似文献   
84.
Vascular endothelial growth factor (VEGF) is a major contributor to retinal neovascularization. The possible participation of VEGF and its high-affinity tyrosine kinase receptors, flk-1 and flt-1, in early background diabetic retinopathy was studied in the streptozotocin-induced diabetic rat model of experimental retinopathy using in situ hybridization, blotting techniques, and immunohistochemistry. Diabetic retinopathy was assessed by quantitative morphometry of retinal digest preparations. The number of acellular capillaries increased 2.7-fold in diabetic animals with diabetes' duration of 6 months compared with nondiabetic controls. VEGF expression was not detectable by in situ hybridization in nondiabetic rats but was highly increased in the ganglion cell layer and in the inner and outer nuclear layers of retinas from diabetic animals. VEGF protein was extractable only from diabetic retinas, and a strong immunolabeling was detected in vascular and perivascular structures. Increased flk-1 and flt-1 mRNA levels were also found in the ganglion cell and both nuclear layers of diabetic samples only. Dot blot and Western blot analyses confirmed the increase in flk-1 mRNA and protein in diabetic retinas. Also, flk-1 immunoreactivity was associated with vascular and nonvascular structures of the inner retinas from diabetic animals. These data obtained from a rodent model in which retinal neovascularization does not occur support the concept that the VEGF/VEGF receptor system is upregulated in early diabetic retinopathy.  相似文献   
85.
86.
Staff nurses are currently being given the opportunity to present inservice offerings as a criterion for the professional performance evaluation. Unfortunately, staff nurses, even those with baccalaureate preparation, generally have not been prepared in strategies for effective teaching. Consequently, many staff nurses either avoid this opportunity altogether or may proceed with the "seat of the pants" approach, making learning a chance event. This article sets forth 10 common-sense teaching strategies for effective inservice education presentations with the goal of encouraging and empowering staff nurses to share their particular area of expertise with their peers.  相似文献   
87.
The paper presents 30-year experience in treating 158 patients with congenital cystic diseases of the liver and bile ducts. Depending on the pattern of hepatobiliary lesions, the diagnostic value of techniques, such as ultrasound, computerized tomography, scintigraphy of the liver duodenoscopy with THCG was defined. Analyzing the late outcomes provided recommendations for the most optimal surgical management: cystic fenestration and tunneling in hepatic polycystosis, pericystectomy in solitary cysts of the liver, different varieties of bile draining operations in choledochal cysts and Caroli's disease.  相似文献   
88.
Female strain A/J mice were exposed to unfiltered or HEPA-filtered environmental tobacco smoke (ETS). Total suspended particulates (TSP) in the full smoke exposure chamber was 78.5 mg/m3 and in the filtered smoke chamber 0.1 mg/m3; nicotine concentrations in the full and filtered smoke chamber were 13.4 and 3.1 mg/m3, respectively. Animals exposed to filtered ETS (6 h a day, 5 days a week) and killed after 5 months had a higher lung tumor incidence and multiplicity than controls maintained in filtered air, although the differences were not statistically significant. Animals exposed to filtered and full ETS and allowed to recover in air for 4 months had an average of 1.2 +/- 0.3 tumors per lung and 1.3 +/- 0.3 tumors per lung, respectively. Air exposed control animals had an average tumor multiplicity 0.5 +/- 0.1 tumors per lung. Increased immunostaining for CYP 1A1 was not evident in the lung of animals exposed to filtered smoke. Based on the chamber concentrations of selected nitrosamines and polycyclic aromatic hydrocarbons, the possible maximum uptakes by the mice of NNK, NNN and benzo[a]pyrene during the 5 months exposure period were three to six orders of magnitude below doses reported in the literature to produce 1 lung tumor in strain A/J mice. It was concluded that the gas phase of ETS is as carcinogenic as is full ETS. The carcinogenicity of the gas phase may be due to some as yet unidentified, yet highly potent carcinogens or by placing a substantial, possibly free radical-mediated oxidative stress on the lung.  相似文献   
89.
Hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are the drugs of choice in heterozygous familial hypercholesterolemia (FH), which has a high risk of ischemic heart disease. An open-label study was conducted to test the efficacy and safety of atorvastatin, a new synthetic HMG-CoA reductase inhibitor in proven FH. After a 4-week placebo phase, 22 subjects were randomized to either 80 mg atorvastatin at night (n = 11) or 40 mg twice a day for 6 weeks. The two dosage groups were well matched and had no difference in lipoprotein responses. After 6 weeks, the LDL cholesterol concentration was reduced by 57%, from 8.16 +/- 1.15 to 3.53 +/- 0.99 mmol/L (P < .001). The total cholesterol concentration decreased from 9.90 +/- 1.32 to 5.43 mmol/L (P < .001). HDL cholesterol concentration increased from 1.19 +/- 0.31 to 1.49 +/- 0.43 mmol/L (P < .001). Triglyceride concentrations decreased from 1.34 +/- 0.66 to 0.88 +/- 0.36 mmol/L (P < .01). Three subjects had single, transient increases of serum transaminase of up to twice the upper limit of normal. Apolipoprotein B concentration decreased significantly by 42%. Changes in apolipoproteins AI and (a) were not statistically significant. Nondenaturing gradient gel electrophoresis revealed increases in the size of smaller LDL particles in four subjects. Plasma fibrinogen concentration increased by 44%. The drug was well tolerated. One subject withdrew for personal reasons. Atorvastatin is a powerful and safe lipid-modifying agent for LDL cholesterol; it also modifies HDL cholesterol and triglyceride concentrations, and may suffice as a single agent for many subjects with heterozygous FH.  相似文献   
90.
Random copolyesters were prepared from dimethyl terephthalate (DMT), ethylene glycol (EG) and butane 1,4-diol (BD) by melt-polycondensation techniques, using varying amounts of EG and BD. Compositions have been established by 1H n.m.r. spectroscopy. Intrinsic viscosity and number average molecular weight (M?n) were measured. Thermal properties have been studied by differential thermal analysis. Melting and crystallization temperatures and thermodynamic parameters are discussed in terms of structural differences, particularly the effect of composition and chain flexibility. The degree of crystallinity from differential thermal analysis, i.r. and wide angle X-ray scattering (WAXS) are discussed.  相似文献   
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