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Impaired recall for early items (primacy) and late items (recency) on word list recall tests are seen in Alzheimer's disease (AD). We compared conventional scoring on the Telephone Instrument for Cognitive Status (TICS) recall list with scorings based on retention-weighted recall (RWR: each item weighted by its serial position) in older adults participating in a community-based aging study. Subjects with mild AD (N=18) did not differ from those without dementia (N=231) with respect to recency (46% vs. 59%, p = 0.2), but had impaired primacy (2% vs. 39%, p < .001) on word recall on the TICS. RWR scoring improved the effect size (1.52 SD) compared to conventional scoring (1.08 SD). With a fixed sensitivity of 85%, specificity was lower using conventional scoring (56%) than RWR (76%) scoring. Our findings suggest that optimized RWR scoring of word list free recall can improve detection of mild AD compared to conventional scoring.  相似文献   
3.
The intubating laryngeal mask airway: an initial assessment of performance   总被引:2,自引:0,他引:2  
A new prototype of the laryngeal mask airway (LMA), the intubating laryngeal mask airway (ILMA), was used to facilitate tracheal intubation in 100 fasted patients presenting for elective surgery. Alignment of the ILMA with the larynx was assessed fibreoptically before intubation without the investigator performing the intubation being aware of the view score. Ease of intubation correlated with the view obtained and with the degree of manipulation of the ILMA needed to achieve tracheal intubation. Intubation was successful in 93 patients. Of the seven intubation failures, five occurred in the first 20 patients. Conventional connection to the breathing system and ventilation of the lungs of the patients were possible throughout the intubation procedure.   相似文献   
4.
Purpose: To determine if adequate anaesthesia and akinesia could be obtained using an inferonasal quadrant sub-Tenons anaesthesia for cataract surgery.
Methods: The sub-Tenons method of local anaesthesia was used in 50 patients undergoing extracapsular cataract extraction and lens implantation. The technique followed was that described by JD Stevens in his study of 50 patients. Posterior sub-Tenons space was approached through a conjunctival incision in the inferonasal quadrant and the anaesthetic solution delivered by an irrigating cannula. The patients were assessed for residual ocular movements just before surgery. Effectiveness of anaesthesia was assessed during surgery using a verbal pain rating score. Scoring was based on the concept of a visual analogue pain score chart.
Results: Total akinesia was obtained in 20% patients and total anaesthesia in 24% patients. The remainder of the patients had adequate akinesia and anaesthesia to proceed with and complete the surgery.
Conclusion: This method provides satisfactory anaesthesia for cataract surgery.  相似文献   
5.
Binding of chemoattractants to their receptors on phagocytes activates a guanine nucleotide regulatory (N) protein through the substitution of GTP for GDP on N. The activated N protein in turn stimulates a membrane-associated phospholipase C by lowering the Ca2+ concentration required to activate this enzyme from supraphysiologic levels to ambient intracellular concentrations. The phospholipase C hydrolyzes phosphatidylinositol 4,5-bisphosphate into the Ca2+ mobilizer inositol 1,4,5-trisphosphate and the protein kinase C activator 1,2-diacylglycerol. In addition to promoting cellular activation, the products of this hydrolysis initiate processes which feed back to inhibit poly-phosphoinositide breakdown. The regulatory model proposed herein may be relevant to other receptors which stimulate polyphosphoinositide metabolism.  相似文献   
6.
OBJECTIVE: To assess the clinical validity of clinical diagnostic criteria for dementia with Lewy bodies (DLB). METHODS: We assessed the sensitivity, specificity, and positive and negative predictive values of the clinical criteria of the Consortium on dementia with Lewy Bodies (CDLB) in 18 patients with autopsy-proven DLB and in 76 patients with dementia not associated with Lewy bodies, using postmortem diagnosis as a gold standard. RESULTS: CDLB criteria had either high sensitivity or high specificity, but no set of criteria simultaneously provided both high sensitivity and high specificity. Clinical criteria had higher predictive validity in patients with pure DLB than in patients with DLB and AD. Seventy-eight percent of patients with pure DLB had two or more major criteria, compared with 44% of patients with DLB and AD (p<0.02). If the nine patients with DLB and AD were excluded from the DLB group, the CDLB criteria for probable DLB had sensitivity of 78% and specificity of 85%. CDLB criteria for probable DLB (two or more major criteria) distinguished DLB from AD with a sensitivity of 78% and a specificity of 64%. CONCLUSIONS: The proposed CDLB criteria have high negative predictive value and thus do well at excluding patients with DLB. Positive predictive value of 75% can be achieved by a combination of any three major or minor criteria, providing the analysis is confined to patients with mild to moderate dementia. Criteria were most accurate if confined to patients with pure DLB who had mild to moderate dementia.  相似文献   
7.
We report both automated rigid and flexible ligand docking simulations performed on fifty peroxisome proliferator-activated receptor (PPAR-γ) agonists, namely, glitazones. The binding conformations and binding affinities of these agonists were obtained by the use of the Autodock 4.1 with Lamarckian genetic algorithm (LGA). All the 50 flexible docks are considered as well-docked as all of them were bound to the ligand binding domain of PPAR-γ. The predicted binding affinity values (pKa) were found to have some degree of correlation with their experimental in vivo activity values. The head group hydrogen bond interactions via H323 and H449 histidine residues were found to play a significant role. The results obtained will be valuable in designing newer selective PPAR-γ agonists.  相似文献   
8.
Multiple endocrine neoplasia type 2A (MEN 2A) is an autosomal dominant inherited condition with a prevalence of one in 40?000 individuals. It causes the development of tumours in endocrine glands, such as medullary thyroid cancer, pheochromocytomas, as well as primary hyperparathyroidism. MEN 2A in pregnancy is very rare with only 29 cases reported in the literature. The presence of pheochromocytoma is a rare cause of hypertension during pregnancy with an incidence of 0.007% of all pregnancies. This has severe implications on both mother and the foetus. This case report describes a 22-year-old nulliparous Caucasian woman with known MEN2A syndrome, who underwent thyroidectomy for medullary thyroid carcinoma in childhood and excision of left sided pheochromocytoma at the age of 19. She was found to have a recurrence of pheochromocytoma in the right adrenal gland during pregnancy at 16 weeks of gestation and was oddly normotensive. Catecholamine effects were blocked with phenoxybenzamine and she delivered by an uneventful elective caesarean section at 36 weeks gestation. She underwent a laparoscopic right adrenalectomy six weeks postpartum, followed by lifelong corticosteroid replacement.  相似文献   
9.
Offspring of parents with exceptional longevity (OPEL), who are more likely to carry longevity-associated genotypes, may age more successfully than offspring of parents with usual survival (OPUS). Maintenance of physical function is a key attribute of successful aging. While many genetic and non-genetic factors interact to determine physical phenotype in aging, examination of the contribution of exceptional parental longevity to physical function in aging is limited. The LonGenity study recruited a relatively genetically homogenous cohort of Ashkenazi Jewish (AJ) adults age 65 and older, who were defined as either OPEL (having at least one parent who lived to age 95 or older) or OPUS (neither parent survived to age 95). Subjective and objective measures of physical function were compared between the two groups, accounting for potential confounders. Of the 893 LonGenity subjects, 365 were OPEL and 528 were OPUS. OPEL had better objective and subjective measures of physical function than OPUS, especially on unipedal stance (p = 0.009) and gait speed (p = 0.002). Results support the protective role of exceptional parental longevity in preventing decline in physical function, possibly via genetic mechanisms that should be further explored.  相似文献   
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