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This study reports that zn-1, a monoclonal antibody, labels hair cells but not supporting cells in the inner ear and the lateral line of the axolotl salamander, Ambystoma mexicanum. Zn-1 immunocytochemically labels the cytoplasm and stereocilia of mature hair cells in the sacculus, in the utriculus, and in the mechanoreceptive neuromast organs of the lateral line. Lower levels of labeling mark newly formed hair cells in the periphery of the sacculus and in regenerating neuromasts. Zn-1 also selectively labels neuronal processes and perikarya in the lateral line nerves and ganglia and the VIIIth cranial nerve and ganglion. Processes and perikarya are labeled by zn-1 in the dorsolateral medulla oblongata, at sites of termination of the afferent octaval and lateral line neurons. Western blot analysis revealed that zn-1 labels one or more proteins with molecular weights of 80 and 160 kDa. The identity of these protein bands remains to be determined. The presence of a specific epitope expressed in both hair cells and neurons, but not in supporting cells, in the vestibular and auditory epithelia of the ear and in the mechanoreceptive neuromasts of the lateral line suggests shared cytogenetic heritages. These findings are consistent with a close evolutionary relationship between otic and lateral line senses, such as that inherent to the theoretical evolutionary scheme outlined in van Bergeijk's "acousticolateralis hypothesis." The protein recognized by zn-1 is as yet unidentified, but its conservative evolution suggests that it may serve an important function in the statoacoustic and lateral line systems.  相似文献   
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恶性肿瘤患者血清与尿液中一氧化氮含量测定   总被引:1,自引:1,他引:0  
0 引言一氧化氮(Nitric oxide,NO)是一种具有活跃生物化学性质的无机小分子. NO对许多肿瘤细胞和微生物有细胞毒性[1],为探讨NO与肿瘤的关系,我们检测了119例恶性肿瘤患者血清及尿液中的NO.  相似文献   
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To explore further the potential for cognitive enhancement utilizing nicotinic stimulation in Alzheimer’s disease (AD), six otherwise healthy subjects with moderate AD received placebo and three doses (6, 12, and 23 mg) of the novel selective cholinergic channel activator (ChCA) (nicotinic agonist) ABT-418 over 6 h in a double-blind, within-subjects, repeated-measures design. Subjects showed significant improvements in total recall and a decline in recall failure on a verbal learning task. Qualitatively similar improvements were seen in non-verbal learning tasks such as spatial learning and memory, and repeated acquisition. No significant behavioral, vital sign, or physical side effects were seen. These results confirm that stimulating central nicotinic receptors has acute cognitive benefit in AD patients. These findings suggest that selective ChCAs have a potential therapeutic role in dementing disorders, and that further studies with this or similar agents in AD and/or Parkinson’s disease are warranted. Received: 27 February 1998/Final version: 9 September 1998  相似文献   
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Verbal recall and recognition were examined in Huntington's disease (HD) and Alzheimer's disease (AD) patients. Subgroups of HD and AD patients were matched for overall severity of dementia. Subjects were administered the Hopkins Verbal Learning Test, a list-learning task with three free-recall trials followed immediately by one yes/no recognition trial with semantically related and unrelated distractors. The matched AD and HD groups did not differ in the number of words recalled, although the HD patients showed slightly greater improvement over trials. Recognition performance was evaluated with measures of accuracy and response bias that are independent of each other. The matched groups did not differ in overall recognition accuracy, but the AD patients tended to have a more liberal ("yea-saying") response bias than did the HD patients. In addition, only the AD patients were differentially enticed to false-positive responding by semantically related distractors. The results suggest that the rule for making decisions when uncertain, rather than memory strength per se, distinguishes the recognition memory performance of AD and HD patients.  相似文献   
16.
Reports on the influence of inhaled glucocorticoids on growth have been controversial. We studied the growth of prepubertal asthmatic children prior to and during glucocorticoid therapy. We collected retrospectively the notes of 201 asthmatic children aged 1–11 years receiving inhaled beclomethasone dipropionate or budesonide. We calculated their height and height velocity standard deviation scores (HSDS and HVSDS, respectively) before the treatment and up to 5 years during the treatment and compared those with the growth of healthy peers. The dose of the medication was calculated and the severity of asthma was assessed. The asthmatic children grew similarly to their healthy peers before treatment with inhaled glucocorticoids: the mean HSDS was +0.02 and the mean HVSDS +0.01 for boys and -0.16 and +0.13 for girls, respectively. Growth retardation took place soon after the start of the treatment, the most profound decrease in the growth velocity (the change in the mean HVSDS from +0.05 to -0.88) occurring during the first year of treatment. The growth-retarding effect of inhaled glucocorticoids was not dose dependent. In the covariance analysis the increasing severity of asthma had a significant interaction with repeated measurements, showing more growth retardation along with more severe asthma, especially during long-term treatment. Asthma per se does not impair growth, but inhaled glucocorticoids may do so. Careful monitoring of the growth of all asthmatic children receiving inhaled glucocorticoids is necessary because the growth-retarding effect of the medication is not dose dependent. Individual sensitivity might explain the differences seen in the growth patterns of children receiving inhaled glucocorticoids.  相似文献   
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Purpose:

To determine if excreted contrast is consistently visualized in the gallbladder and duodenum after a 30‐minute delay using gadoxetate disodium‐enhanced MRI in patients without hepatobiliary disease.

Materials and Methods:

Twenty‐two patients without evidence of liver or biliary disease underwent gadoxetate disodium‐enhanced magnetic resonance imaging (MRI) from February 17, 2009 through October 3, 2011. The mean age was 45 years (range 25–72). T1‐weighted hepatobiliary phase images at 5, 10, 20, and 30 minutes after contrast injection were reviewed in consensus by two radiologists to determine the delay at which enhancement of the gallbladder and duodenum first occurred.

Results:

Thirteen of 22 (59.1%) patients demonstrated duodenal filling by 20 minutes and 16/22 (72.7%) filled by 30 minutes. The mean time to duodenal enhancement was 19.9 minutes (range 11.4–30.2 min). Seventeen of 22 (77.3%) patients demonstrated gallbladder filling by 20 minutes and 21/22 (95.5%) filled by 30 minutes. The mean time to gallbladder enhancement was 16.5 minutes (range 4.4–30.2 min).

Conclusion:

A significant number of normal patients do not show duodenal filling by 30 minutes, while the majority fill the gallbladder by 30 minutes using functional MR cholangiography (fMRC) with gadoxetate disodium. These findings will guide fMRC protocol design for patients with suspected acute cholecystitis and sphincter of Oddi dysfunction. J. Magn. Reson. Imaging 2013;37:993–998. © 2012 Wiley Periodicals, Inc.  相似文献   
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