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41.
Frequency receptive fields (RFs) were determined before and after pairing iontophorectic administration of acetylcholine (ACh) with a repeated single-frequency stimulus in the auditory cortex of barbiturate-anesthesized cats. In 58% of the cells, the paired ACh + tone treatment produced subsequent alterations of frequency RFs. In half of these cases, the RF modifications were highly specific to the frequency that had been paired with ACh. Atropine antagoized the frequency-effects of ACh, suggesting that they were mediated via muscarinic cholinergic receptors. 相似文献
42.
A longitudinal study of cholinesterase changes in pregnancy 总被引:1,自引:0,他引:1
Serum cholinesterase activity was measured at intervals before, during, and after 44 pregnancies in 43 women. Three patterns of change were seen: (a) A decline in activity after conception, with no return towards pre-conception values before delivery (20 pregnancies). (b) A decline in activity accompanied by a partial or complete return to pre-conception values before delivery (19 pregnancies). (c) Either no discernible decline or increased activity during gestation (five pregnancies). We saw no association between these patterns and either the sex of the child, parity, smoking history, or alcohol intake. However, the continuous decrease in cholinesterase activity occurred in the youngest group of women, a decrease followed by an increase in the intermediate age group, and no decrease at all in the oldest group. Although not all the age-related differences quite reached statistical significance, these findings suggest that the patterns of change may be determined by some aspect of maternal physical maturity. 相似文献
43.
44.
Effect of Multiple Freeze-Thaw Cycles on Detection of Measles, Mumps, and Rubella Virus Antibodies 下载免费PDF全文
Norman A. Pinsky Jeanne M. Huddleston Robert M. Jacobson Peter C. Wollan Gregory A. Poland 《Clinical and Vaccine Immunology : CVI》2003,10(1):19-21
We investigated the effect of multiple freeze-thaw cycles on mumps, measles, and rubella virus serum antibody levels with whole-virus immunoglobulin G enzyme-linked immunoassays. Fresh serum samples from nine healthy adult volunteers were divided into six sets of five aliquots each. Samples were taken through a total of 10 freeze-thaw cycles and stored at 4°C until assayed. Each assay measurement was done in replicates of five, and the mean value was reported. After completing 10 freeze-thaw cycles, we found no clinically or statistically significant effect on measured antibody levels and found no discernible detrimental effect on the ability to measure these antibodies by enzyme-linked immunoassays. 相似文献
45.
46.
Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
47.
48.
E.J. Norman 《Medical hypotheses》1991,36(4):374-375
It is suggested that the thermic effect of protein be exploited as a means of hyperthermia therapy in the treatment of liver cancer. Oral ingestion of high amounts of protein or intravenous amino acid therapy could generate heat directly within the hepatocytes primarily through urea synthesis. This approach could enhance the effects of conventional hyperthermia or radiation therapy. 相似文献
49.
M Cecilia Lansang Caroline Coletti Sofia Ahmed Michael S Gordon Norman K Hollenberg 《Journal of the renin-angiotensin-aldosterone system》2006,7(3):175-180
BACKGROUND: Thiazolidinediones (TZD) have been reported to improve early stages of diabetic nephropathy independent of glycaemic control. Since blockade of the renin-angiotensin system (RAS) is known to reduce the risk of nephropathy, we hypothesised that the renal effect of TZDs might be related to a favourable effect on the intrarenal RAS. We aimed to determine if the TZD rosiglitazone could reduce RAS activation. METHODS: We studied adult type 2 diabetic patients and placed them on rosiglitazone for three months. We have previously used the renal haemodynamic response to angiotensin-converting enzyme (ACE) inhibition to demonstrate the state of RAS activation, and thus measured renal plasma flow (RPF) and glomerular filtration rate (GFR) before and after administration of captopril at 0 month and at three months. Plasma renin activity (PRA), active renin, aldosterone and natriuretic peptides were analysed. RESULTS: The RPF response to ACE inhibition was not altered. There was no change in GFR, PRA, active renin and aldosterone levels. Two patients developed oedema one had an elevated baseline active renin and another had an elevated baseline aldosterone level. CONCLUSION: The favourable effects of TZDs on diabetic nephropathy is likely not related to an influence on the RAS. 相似文献
50.
Nancy I Thomas Norman DePaul Brown Linda C Hodges Jay Gandy Louanne Lawson Janet E Lord David K Williams 《AAOHN journal》2006,54(1):24-31
The Central Arkansas Veterans Healthcare System (CAVHS) spends $1 million annually on occupational illnesses and injuries. To address the problem of injuries among hospital employees, a retrospective case-control study was conducted to examine select risk factors for work-related injuries (WRI) among CAVHS employees. Study methods included a review of employee health charts and computer and manual databases from 1997 to 2002 (N = 2,050). The researchers found that WRI increased with age; WRI occurred more often in women than in men; WRI was greater among maintenance and custodial staff compared to direct caregivers, and less among clerical staff; WRI occurred less often in part-time than full-time staff; and WRI increased with increasing body mass index. Developing standards, guidelines, and policies for preplacement screening, preventive measures, training, and education may help to minimize WRI and associated costs. 相似文献