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61.
Seeing but not recognizing   总被引:1,自引:0,他引:1  
Visual recognition disturbances are caused by lesions that affect visual cortex as well as white matter connections between visual cortex and temporal and parietal cortex. Homonymous visual field defects are often present but do not explain the recognition difficulty. In "alexia without agraphia" (pure alexia), the intact right visual cortex is disconnected from the left parietal language center by a lesion in the splenium. In "prosopagnosia," visual cortex is disconnected bilaterally from temporal cortex. In simultanagnosia, visual association cortex is damaged. The first condition is most commonly caused by left posterior cerebral artery occlusion, the second by bilateral posterior cerebral artery occlusion or head trauma, and the third by watershed infarction, tumors, abscesses, head trauma, leukoencephalopathies and Alzheimer's disease. When such disorders are suspected, the examiner should supplement the routine visual examination with suggested screening maneuvers.  相似文献   
62.
We studied the influence of radiation therapy on lymphocyte subpopulations in 17 patients undergoing adjuvant radiation therapy for primary breast cancer, and eight patients receiving brachytherapy and external beam irradiation for primary cancer of the uterus. Radiation therapy reduced B- and T-lymphocytes in proportion to the total lymphocyte population so that their percentages remained unchanged. Determination of helper and suppressor T-lymphocytes before, during and 6 months after completion of radiotherapy revealed that in both groups of patients suppressor T-lymphocytes were more resistant to and recovered faster after radiotherapy. This resulted in a decline of the "immunoregulatory balance" (helper/suppressor ratio). Although this ratio had been higher in both groups of patients than in healthy age- and sex-matched controls before therapy, it became normal and subnormal during and after radiotherapy. The clinical significance of the differential influence of radiotherapy on T-lymphocyte subpopulations remains to be determined.  相似文献   
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Introduction It has been demonstrated that urinary neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin are helpful biomarkers in the differentiation of intrinsic and prerenal acute kidney injury.Objective The present cross-sectional study investigates, whether urinary biomarkers are able to differentiate primarily inflammatory from non-inflammatory entities in chronic kidney disease (CKD).Methods Urinary calprotectin, NGAL, and kidney injury molecule-1 (KIM-1) concentrations were assessed in a study population of 143 patients with stable CKD and 29 healthy controls. Stable renal function was defined as an eGFR fluctuation ≤5 ml/min/1.73 m2 in the past 12 months. Pyuria, metastatic carcinoma, and renal transplantation were regarded as exclusion criteria. Diabetic nephropathy, hypertensive nephropathy, and polycystic kidney disease were categorized as ‘primarily non-inflammatory renal diseases’ (NIRD), whereas glomerulonephritis and vasculitis were regarded as ‘primarily inflammatory renal diseases’ (IRD).Results Urinary calprotectin and NGAL concentrations significantly differed between CKD and healthy controls (p < 0.05 each), whereas KIM-1 concentrations did not (p = 0.84). The three biomarkers did neither show significant differences in-between the individual entities, nor the two categories of IRD vs. NIRD (calprotectin 155.7 vs. 96.99 ng/ml; NGAL 14 896 vs. 11 977 pg/ml; KIM-1 1388 vs. 1009 pg/ml; p > 0.05 each). Albumin exceeds the diagnostic power of the investigated biomarkers by far.Conclusions The urinary biomarkers calprotectin, NGAL, and KIM-1 have no diagnostic value in the differentiation of primarily inflammatory vs. non-inflammatory etiologies of CKD.  相似文献   
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Purpose. Prolonged continuous administration of nitroglycerin (NTG) leads to hemodynamic tolerance. We used a previously developed pharmacokinetic-pharmacodynamic (PK/PD) model of NTG tolerance in experimental heart failure to test whether dosage regimens, designed from this model, may allow avoidance of tolerance development upon continuous NTG inftision. Methods. Simulation experiments (using ADAPT II) were performed to evolve a time-variant infusion regimen that would theoretically provide sustained hemodynamic effect (30% reduction in left ventricular end-diastolic pressure, LVEDP) throughout 10 hours of drug dosing. A computer controlled infusion pump was utilized to deliver this time-variant input. Infusion experiments were then conducted in CHF rats to challenge the predictability of the applied PK/PD model. Results. Simulations showed that exponentially increasing input functions provided more sustained LVEDP effects when compared to linear or hyperbolic input functions delivering the same total NTG dose. A computer-selected infusion regimen of 6.56e0.00156×minutes g/min was anticipated to provide the desired hemodynamic profile in our animal model. Experiments conducted in rats with congestive heart failure (n = 4) confirmed the prediction of sustained hemodynamic effect without tolerance (28 ± 4% reduction in LVEDP at 10 hrs). Conclusions. These findings support the utility of our PK/PD model of NTG tolerance in predicting NTG action, and serve as an example of therapeutic optimization through PK/PD considerations.  相似文献   
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This paper is drawn from a large phenomenologically based study which investigated the nursing home carers' experiences of elderly residents' sexuality. Joking and teasing with the residents was an acknowledged way for staff to deal with sexuality in the nursing home. Whilst humor can be used in a therapeutic way to establish and maintain rapport, as well as to deal with incidents which are uncomfortable, joking is also known to be an effective way to manipulate and control people. Teasing can be used as an effective strategy to discourage certain types of behavior.  相似文献   
69.
Papillary clear cell adenocarcinoma of the groin arising from endometriosis   总被引:3,自引:0,他引:3  
A 67-year-old woman presented with rapidly enlarging right anterior thigh mass. Clinical impression was of a primary sarcoma, but the histologic analysis of an incisional biopsy specimen showed adenocarcinoma with clear cell differentiation. Initially thought to be a metastasis, the malignant tumor appears to have arisen from extraabdominal endometriosis of the right groin. This case shows clinical, radiographic, and histologic findings that may help the orthopaedic surgeon recognize an unusual complication of extrapelvic endometriosis.  相似文献   
70.
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