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41.
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The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature.  相似文献   
43.
OBJECTIVE: Behavioral disturbances in dementia are extremely prominent and distressful, and often result in serious physical, social, and economic consequences. The authors compared the efficacy and tolerability of risperidone and haloperidol in the treatment of behavioral and psychological symptoms of dementia (BPSD) in institutionalized elderly Korean patients with Alzheimer disease, vascular dementia, or mixed dementia. METHODS: This was an 18-week double-blind, crossover study involving 120 patients who were randomly assigned to receive flexible doses (0.5-1.5 mg/day) of risperidone or haloperidol. BPSD were assessed using the Korean version of the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD-K), the Korean version of the Cohen-Mansfield Agitation Inventory (CMAI-K), and the Clinical Global Impression of Change scale (CGI-C). Safety and tolerability assessments included the Extrapyramidal Symptom Rating Scale and the incidence of adverse events. RESULTS: Both risperidone and haloperidol were efficacious in alleviating BPSD. However, when receiving risperidone, patients showed significantly greater improvement than when receiving haloperidol in the total and subscale scores of the BEHAVE-AD-K, the total and subscale scores of the CMAI-K, and the scores on the CGI-C scale. Also, risperidone had an additional benefit on aggressiveness and anxieties/phobias. The risk of antipsychotic-induced parkinsonism throughout this study was significantly lower with risperidone than with haloperidol. CONCLUSION: Risperidone had a favorable efficacy and tolerability profile compared with haloperidol in the treatment of BPSD in this patient population.  相似文献   
44.
The retrosplenial cortex is a cytoarchitecturally distinct brain structure located in the posterior cingulate gyrus and bordering the splenium, precuneus, and calcarine fissure. Functional imaging suggests that the retrosplenium is involved in memory, visuospatial processing, proprioception, and emotion.We report on a patient who developed reversible verbal and visual memory deficits following a stroke. Neuropsychological testing revealed both anterograde and retrograde memory deficits in verbal and visual modalities. Brain diffusion-weighted and T2-weighted magnetic resonance imaging (MRI) demonstrated an acute infarction of the left retrosplenium.  相似文献   
45.
The modifying effects of atrazine, and/or tamoxifen, on thyroid carcinogenesis were investigated in a rat two-stage carcinogenesis model following N-bis(2-hydroxypropyl)nitrosamine (DHPN) initiation. Five-week-old male F344 rats were given a single subcutaneous injection of DHPN (2800 mg/kg, body weight) or vehicle alone. Starting 1 week later, the animals were fed a diet supplemented with 0, 5, 50 or 500 ppm of atrazine, 500 ppm atrazine plus 5 ppm tamoxifen, or 5 ppm tamoxifen in the DHPN-treated groups, and 0 or 500 ppm of atrazine in the DHPN-untreated groups for 24 weeks. At autopsy major organs, including the thyroid, pituitary, liver, kidney, testis, epididymis, and brain, were collected and histopathologically examined. Body weights were significantly (P<0.05) decreased by the high doses of atrazine or tamoxifen, the effect being enhanced in combination. Relative thyroid weights were significantly increased (P<0.05) only in the tamoxifen-treated group and pituitary weights were elevated with 500 ppm atrazine plus tamoxifen (P<0.05). Relative liver weights were increased by the high dose of atrazine. However, the atrazine and/or tamoxifen treatments did not induce significant histopathological changes in the major organs, including the thyroid, nor cause significant changes in serum TSH levels. These results suggest that neither atrazine nor tamoxifen may promote thyroid carcinogenesis, alone as well as in combination.  相似文献   
46.
Bilateral perioral sensory dysfunction due to unilateral cerebral lesion is rare, and has been thought to be caused by midline brainstem lesions. Six patients are described herewith, with bilateral perioral sensory symptoms due to unilateral strokes that do not involve the mid-brainstem region. Brain-computed tomographic scan and magnetic resonance imaging demonstrated unilateral cerebral strokes in the thalamus, posterior limb of the internal capsule, basal ganglia, fronto-parietal cortex and the insular-frontal subcortical area. This observation suggests that bilateral perioral sensory symptoms do not have a localizing value. Possible pathogenetic mechanisms for this sign are discussed.  相似文献   
47.
Summary A series of 55 randomly chosen radical prostatectomy specimens was analyzed for expression of prostate-specific antigen (PSA) by immunohistochemical techniques. Tissue sections were selected in such a manner that in addition to glandular benign prostatic hyperplasia (BPH), one or more different prostatic tumour growth patterns were present. Four monoclonal antibodies, directed against three different PSA epitopes, and one polyclonal anti-PSA antiserum were used. Expression of PSA was compared with that of prostate-specific acid phosphatase (PAP), recognized by two different polyclonal antisera. A critical dilution aimed at a maximum of staining intensity on BPH tissue sections was chosen for all antibodies. Anti-PSA and anti-PAP antisera stained essentially all BPH samples (over 90%). Irrespective of the nature of the antibodies used, PSA expression was found to be decreased in prostatic carcinoma. A clear cut relationship was found between immunoreactivity for PSA and the degree of differentiation of the tumour area. Under the experimental conditions used the PSA monoclonal antibodies stained only 1 out of 10 undifferentiated carcinomas, whereas 50% to 70% of the well- and moderately-differentiated carcinomas showed immunoreactivity. This correlation was less pronounced with the PAP staining pattern. If the PSA antibody titer was raised the percentage of clearly staining undifferentiated carcinomas could be considerably increased (up to 60%–100%), indicating that PSA expression is not absent, but lowered in most (if not all) undifferentiated carcinomas.  相似文献   
48.
49.
The pentose sugar L-arabinose is one of the most abundant components released by complete hydrolysis of non-starch polysaccharides of feed ingredients of vegetable origin. Two studies were conducted to investigate the apparent ileal digestibility and urinary excretion of L-arabinose at dietary inclusion levels of 50 and 100 g/kg, and 25, 50, 75 and 100 g/kg respectively, in pigs. As a reference, D-glucose was included in the studies. Water intake, ileal flow of volatile fatty acids and ileal and faecal digestibilities of dietary nutrients in pigs fed on the different diets were also examined. Castrated pigs were prepared with a post-valvular T-caecum cannula to measure ileal digestibility. Faecal digestibility was measured in non-cannulated pigs. Apparent ileal digestibility of L-arabinose was found to be approximately 70%. The presence of L-arabinose in the diet increased ileal flow of volatile fatty acids and lactic acid, suggesting the occurrence of microbial degradation of L-arabinose in the pig small intestine. L-arabinose was partly excreted in the urine. The extent of this urinary excretion as a percentage of intake increased linearly (P < 0.01) as the dietary level increased. In pigs fed on the 25 g L-arabinose/kg diet, 10.9% of the L-arabinose consumed appeared in the urine. This level was increased to 14.7% when pigs were fed on a diet containing 100 g L-arabinose/kg diet. Faecal digestibility and retention of nitrogen decreased significantly in pigs fed on the L-arabinose diets.  相似文献   
50.
Toluene diisocyanate (TDI), a low molecular weight reactive chemical, is known to be a main cause of occupational asthma (OA) in Korea. Although it is thought that inhaled TDI may act as a hapten, the precise mechanisms of TDI-induced OA are unknown. In this study, TDI-human serum albumin (HSA) conjugates (5, 10, 20 and 30 min) were prepared in the range of 1.5 to 5.0 TDI mole/HSA mole. Specific binding of serum IgE to TDI-HSA (30 min) was observed using IgE ELISA as well as ELISA inhibition assay. Around 40% of TDI-induced OA patients were positive for serum specific IgE by ELISA. Degrees of serum IgE binding were different depending on which TDI-HSA conjugate was used as an antigen. Moreover, binding patterns were different depending on the individuals. Interestingly, higher binding of IgE to TDI-HSA (5 min) than to TDI-HSA (30 min) which was more highly substituted was observed in some patients. Probably new antigenic epitopes on carrier proteins were targets of the specific IgE. The results of this study indicated that IgE responses to TDI-HSA conjugates were heterogeneous in TDI-induced OA patients and self-proteins modified by reactive chemicals can become a major target antigen of IgE in certain cases.  相似文献   
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