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991.
OBJECTIVE: To look for preclinical markers of Alzheimer's dementia in a sample of healthy, oldest old individuals. DESIGN: Prospective, longitudinal study of individuals examined at yearly intervals with neuropsychological tests selected to be sensitive to the early detection of dementia. PARTICIPANTS: One hundred and thirty-nine community-dwelling, functionally independent, healthy individuals 65 to 106 years of age who met strict criteria for lack of dementia at entry. Incident dementia cases consisted of 16 volunteers all 80 years old or older who developed dementia of the Alzheimer's type and 31 volunteers 80 years old and older showing no evidence of dementia during a mean 2.8-year follow-up interval. MEASUREMENTS: Scores on 10 neuropsychological measures were analyzed for the initial examination when none of the volunteers showed clinical evidence of dementia and for the two subsequent yearly examinations. RESULTS: Individuals who subsequently developed dementia showed evidence of verbal memory impairment at their initial examination, which was a mean of 2.8 years before clinical evidence of dementia. The average yearly incidence rate for dementia in those 80 years of age and older was 12%. Performance of individuals who did not development dementia remained relatively stable during follow-up for up to 5 years. CONCLUSION: Alzheimer's disease has a preclinical stage in which verbal memory decline is the earliest sign. Dementia in the oldest old is distinguishable from age-related cognitive decline.  相似文献   
992.
Expression processes under variable-pressure condition are analyzed in view of the flow through compressible porous media. It has been demonstrated that the expression mechanism of slurry consists of two flow phenomena and these types of phenomena can be analyzed first by filtration theory and second by the so-called consolidation theory.

By assuming that the continuous screw expression process con- sists of a succession of batch processes, the basic equations ex- pressing the relationship between the dehydration rate, the feed rate, and the expression pressure distribution are derived.  相似文献   
993.
994.
The effects of nitrous oxide (75%) on the spinal dorsal born wide dynamic range (WDR) neuronal activity were studied in either spinal cord intact or spinal cord-transected cats. Extracellular activity was recorded in the dorsal horn from single WDR neurons responding to noxious and non-noxious stimuli applied to the cutaneous receptive fields on the left bind foot pads of intact or decerebrate, spinal cord-transected (L 1-2) cats. The experiment was divided into four sections as follows: (1) When 10 micrograms of bradykinin (BK) was injected into the femoral artery ipsilateral to the recording site as the noxious test stimulus in the spinal cord-transected cat, all of 6 WDR neurons gave excitatory responses which were not depressed by 75% nitrous oxide. (2) When the injection of 10 micrograms of BK into the femoral artery ipsilateral to the recording site was used in the spinal cord-intact cat, 6 of 15 WDR neurons (40%) gave excitatory responses, which were significantly depressed by 75% nitrous oxide, and 9 of 15 WDR neurons (60%) gave inhibitory responses, which were not affected by 75% nitrous oxide. (3) When 10 micrograms of bradykinin (BK) was injected into the femoral artery contralateral to the recording site as the noxious test stimulus in the spinal cord transected cat, 6 of 12 WDR neurons gave excitatory reasons, which were not depressed by 75% nitrous oxide. (4) When the injection of 10 micrograms of BK into the femoral artery contralateral to the recording site was used in the spinal cord-intact cat, 6 of 6 WDR neurons (100%) gave responses, which were affected by 75% nitrous oxide. We have observed that nitrous oxide reduces the excitation and inhibition of dorsal born WDR neuronal activities induced by BK injection in spinal cord-intact cats, but does not reduce the excitation of those in spinal cord-transected cats. This finding confirmed that the antinociceptive effect of nitrous oxide might be modulated by supraspinal descending inhibitory control systems. In addition our result showed that the supraspinal effect of nitrous oxide was mediated not only by an increase but also a decrease in a supraspinal descending inhibition.  相似文献   
995.
PURPOSE: We evaluated the safety of indocyanine green for use in fundus angiography. METHODS: We sent a questionnaire concerning complications of indocyanine green to 32 institutions in Japan, which were selected on the basis of the client list from the Topcon Company, which manufactures the indocyanine green fundus camera. RESULTS: Ophthalmologists at 15 institutions responded, reporting a total of 3,774 indocyanine green angiograms performed on 2,820 patients between June 1984 and September 1992. Before angiography, intradermal or intravenous indocyanine green testing, or both was performed at 13 of 15 institutions. For three patients, the decision was made not to proceed with angiography after positive preangiographic testing. The dosage of indocyanine green used for angiography varied from 25 to 75 mg, depending upon the institution. There were 13 cases of adverse reactions (0.34%), ten of which were mild reactions such as nausea, exanthema, urtication, itchiness, and urgency to defecate, and did not require treatment. Also recorded were one case of pain of the vein, which required treatment, and two cases of hypotension. The two hypotensive patients required treatment for shock. CONCLUSIONS: A comparison of frequency of adverse reactions to indocyanine green with the previously reported frequency of such reactions to fluorescein sodium indicated that indocyanine green is a safe as fluorescein for use in angiography.  相似文献   
996.
997.
Twelve patients with rheumatoid arthritis treated for at least 12 months with methotrexate and 11 matched rheumatoid arthritis controls underwent a standard d-xylose absorption test. No patients had any pre-existing clinical of biochemical evidence of malabsorption. No significant difference was observed in the 1 hour plasma d-xylose estimation between methotrexate treated patients and controls. The 2 to 5 hour urinary excretion ratio, however, was significantly lower in the methotrexate-treated group compared with controls indicating a minor degree of malabsorption. Six of the methotrexate treated patients and 5 of the controls underwent endoscopic duodenal biopsy but neither group demonstrated any significant histological changes. In conclusion, methotrexate therapy in patients with rheumatoid arthritis produces mild intestinal malabsorption.  相似文献   
998.
999.
1000.
We evaluated the usefulness of the intubating laryngeal mask airway (ILMA) in patients who were predicted to have possible difficult airway. Patients with possible difficult airway were defined as those with limited head extension, Mallampati's classification of grade IV, thyro-mental distance < 4 cm, or Cormack grade III-IV on the laryngoscopy. The control group was consisted of the patients without these conditions or impaired mouth opening. Insertion of the ILMA was successfully performed in all patients of both groups. In the group of possible difficult airway, 83% of patients were intubated through the ILMA successfully, and in the control group, 86%. We conclude that the ILMA may become an additional tool in patients with difficult intubation.  相似文献   
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