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101.
Obese persons with hypertension are at greater risk for diabetes and hyperlipidemia than normotensive obese persons. It has been postulated that increased lipolytic rates contribute to these metabolic diseases. Therefore, we evaluated the glycerol rate of appearance (Ra) in plasma, an index of whole-body lipolytic activity, during basal conditions and during 60 minutes of epinephrine infusion after 12 and 84 hours of fasting in six normotensive (body mass index [BMI], 39.9 +/- 1.8 kg/m2) and six hypertensive (BMI, 38.7 +/- 1.6 kg/m2) obese persons. Basal glycerol Ra was lower in hypertensive than in normotensive subjects at both 12 hours (1.58 +/- 0.21 v 2.27 +/- 0.28 mumol/kg/min, respectively; P < .01) and 84 hours (2.04 +/- 0.06 v 2.50 +/- 0.13 mumol/kg/min, respectively; P < .01) of fasting. Peak glycerol Ra during epinephrine infusion after 84 hours of fasting (5.69 +/- 0.72 and 11.40 +/- 0.78 mumol/kg/min for hypertensive and normotensive subjects, respectively) was significantly greater than at 12 hours (3.09 +/- 0.29 and 5.06 +/- 0.69 mumol/kg/min) in both hypertensive and normotensive subjects. However, peak glycerol Ra was lower in hypertensive than in normotensive subjects after 12 and 84 hours of fasting (P < .01 for 84 hours). We conclude that hypertension in obese persons is associated with a decrease in both basal lipolytic rates and lipolytic sensitivity to epinephrine infusion.  相似文献   
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This study tests the hypothesis that sentence comprehension difficulty in Parkinson's disease (PD) is related in part to altered information processing speed that plays a crucial role in grammatical processing. The authors measured information processing speed in 32 PD patients without dementia using a lexical list-priming paradigm in which the interstimulus interval (ISI) between the prime and the target varied. Sentence comprehension accuracy was also assessed in 22 of these patients. Sentence comprehension accuracy for object-relative center-embedded sentences was impaired in a subgroup of PD patients. This subgroup of PD patients primed at an abnormally long ISI. Similarly, only PD patients who primed at a long ISI had greater difficulty understanding sentences with an object-relative clause than a subject-relative clause. Findings suggest that slowed information processing speed contributes to sentence comprehension difficulty in PD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper is a light microscopical study describing the detailed morphology and quantitative distribution of local circuit neurones in areas 25, 32, and 24b of the medial prefrontal cortex (mPFC) in the rat. Cortical interneurones were identified immunocytochemically by their expression of calretinin (CR), parvalbumin (PV), and calbindin D-28k (CB) immunoreactivity. Neurones immunoreactive for gamma-aminobutyric acid (GABA) were also investigated, as were interneurones containing reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activity. Several distinct classes of CR+, PV+, and CB+ neurones were identified; the most frequent were: bipolar/bitufted CR+ cells in upper layer 3; multipolar PV+ neurones in layers 3 and 5; and bitufted/multipolar CB+ neurones in lower layer 3. CB+ neurones resembling Martinotti and neurogliaform cells were also present in layers 5/6. The morphologies and depth distributions of each cell type were consistent across the three areas of mPFC studied. Seven classes of diaphorase-reactive mPFC neurone are described; these cells were composed about 0.8% of the total neurone population and had a peak distribution located in mid- to lower layer 5 in each area. In areas 32 and 25, three defined bands of diffuse NADPH diaphorase staining were located in layer 2 and in upper and deep layer 5. Diaphorase reactivity was very infrequently colocalised with either CR, PV, or CB immunoreactivities. The numerical densities of neurones (N(V), number of cells per mm3) in each layer were calculated stereologically. The mean total neuronal N(V) estimate for areas 25, 32, and 24b was 51,603 +/- 3,324 (mean +/- S.D.; n = 8). Significant interareal differences were detected. From cortical thickness data and neuronal N(V) estimates, the absolute number of neurones under 1 mm2 of cortical surface (N(C)) have been derived. The mean N(C) value for areas 25, 32, and 24b was 57,328 +/- 7,505 neurones. In immunolabelled Nissl-stained sections, CR+ neurones constituted an overall 4.0%, PV+ cells 5.6%, and CB+ 3.4% of the total neurone populations in mPFC. GABA+ cells represented a mean of 16.2% (14.8-17.2%) of neurones in areas 25, 32 and 24b. The absolute numbers of CR+, PV+, CB+, and GABA+ neurones within individual layers in a column of cortex under 1 mm2 of cortical surface (N(L)) have also been derived, with significant interareal differences in N(L) values being detected. The data provide the structural basis for a qualitative and quantitative definition of local cortical circuits in the rat mPFC.  相似文献   
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PURPOSE: A multiinstitutional trial was performed to confirm the clinical activity, in terms of response rate and toxicity (primary objectives) and duration of responses and survival (secondary objectives), of an intensive weekly regimen in advanced gastric cancer. PATIENTS AND METHODS: Patients with measurable unresectable and/or metastatic gastric carcinoma received 1-day per week administration of cisplatin (CDDP) 40 mg/m2, fluorouracil (5FU) 500 mg/m2, epi-doxorubicin (epi-ADR) 35 mg/m2, 6S-stereoisomer of leucovorin 250 mg/m2, and glutathione 1.5 g/m2. On the other days, filgrastim was administered by subcutaneous injection at a dose of 5 mg/kg. One cycle of therapy consisted of eight 1-week treatments. Patients who showed a response or stable disease received a further 6 weeks of therapy. RESULTS: Of 105 enrolled patients, 11 had locally advanced unresectable disease only; 33 had primary nonresected and metastatic disease; 48 had metastatic disease and primary tumor resected; 10 had locoregional recurrence and metastatic disease; and three had locoregional recurrence only. After one cycle, 18 complete responses (CRs) and 47 partial responses (PRs) were achieved, for an overall response rate of 62% (95% confidence interval [CI], 53% to 71%). Twenty patients had stable disease and 20 progressed on therapy. The median survival duration of all 105 patients was 11 months, with 1- and 2-year survival rates of 42% and 5%, respectively. World Health Organization (WHO) grade III to IV toxicity, in terms of anemia, neutropenia, thrombocytopenia, and mucositis, was experienced by 40 patients (38%). There were no treatment-related deaths. CONCLUSION: These data support the results of the pilot study and confirmed the high activity of the regimen, with acceptable toxicity. This schedule deserves evaluation in the adjuvant setting.  相似文献   
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To investigate the effects of a new nonNMDA antagonist on the trisynaptic pathways in the hippocampus, the author examined kainate(KA)-induced generalized seizures in rats. A novel nonNMDA antagonist, YM90K, showed the blockade of the Schaffer collaterals in 2-deoxyglucose study (2-DG) and that the CA1-2 pyramidal cells of the hippocampus were preserved seven days after the KA injections. On the other hand, the control and MK-801 (NMDA-antagonist) treated rats did not depress the Schaffer collaterals and showed persistent hypermetabolism of glucose in the CA1 pyramidal cell layer, where neurons were not preserved seven days later. 2-DG was useful to reveal the effects of nonNMDA antagonist on the KA-induced generalized seizures. This suggests that YM90K is a potent nonNMDA antagonist and that it has a neuroprotective effect in rats.  相似文献   
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The goal of this research was to examine the accuracy of three methods used to indicate the hip joint center (HJC) in seated steady-state cycling. Two of the methods have been used in previous studies of cycling biomechanics and included tracking a marker placed over the superior aspect of the greater trochanter, a location that estimates the center of rotation of the hip joint, and assuming that the hip is fixed. The third method was new and utilized an anthropometric relationship to determine the hip joint location from a marker placed over the anterior-superior iliac spine. To perform a comparative analysis of errors inherent in the three methods, a standard method which located the true hip joint center was developed. The standard method involved establishing a pelvis-fixed coordinate system using a triad of video markers attached to an intracortical pin. Three-dimensional motion analysis quantified the true hip joint center position coordinates. To provide data for the comparative analysis, the intracortical pin was anchored to a single subject who pedaled at nine cadence-workrate combinations while data for all four methods were simultaneously recorded. At all cadence-workrate combinations the new method was more accurate than the trochanter method with movement errors lower by a factor of 2 in the vertical direction and a factor of 3 in the horizontal direction. Relative to the errors introduced by the fixed hip assumption, the new method was also generally more accurate by at least a factor of 2 in the horizontal direction and had comparable accuracy in the vertical direction. For computed kinetic quantities, the new method most accurately indicated hip joint force power but the fixed hip method most accurately indicated the work produced by the hip joint force over the crank cycle.  相似文献   
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