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101.
Ca2+/calmodulin-dependent protein kinase I (CaM-kinase I) in rat retina was analyzed by immunohistochemical analysis, Western blot analysis and kinase activity assay. Western blot analysis revealed two immunoreactive bands similar to those detected in the brain. Developmental studies revealed that CaM-kinase I expression increased in accordance with postnatal development. Expression of CaM-kinase I in the retinas of rats raised in the complete darkness markedly decreased. CaM-kinase I activity assay supported these findings. Synapsin I was shown to be a possible intrinsic substrate of CaM-kinase I in rat retina. These results elucidated that CaM-kinase I is expressed in the retina and may play an important role in the retinal functions and that the expression of CaM-kinase I is regulated by light stimulation.  相似文献   
102.
We have established a novel smooth muscle cell line (SVS) which retains the expression of specific markers for smooth muscle cells, such as smooth muscle myosin-1, calponin and SM22 alpha, from temperature-sensitive SV40 large T-antigen transgenic mice. SVS cells showed temperature-dependent growth and the expression of smooth muscle markers, showing that the differentiation stage can be controlled in this cell line by culture temperature. We have constructed luciferase-reporter cell lines for calponin and SM22 alpha genes by using SVS cells. We detected some compounds including ascorbic acid, which stimulated the expression of smooth muscle markers by the reporter assay. Ascorbic acid and its long lasting derivatives stimulated the expression of markers continuously. Moreover, ascorbic acid activated the expression of markers in synthetic SMCs seen in the intima of a rat balloon injury model. Thus, this reporter system should be useful for discovery of new antiatherosclerotic drugs.  相似文献   
103.
Quinones were studied for their growth inhibitory effect on cultured malignant cells. HCT-15 cells derived from human colon carcinoma were used for these experiments. Quinones used were arbutin in the benzoquinone group, juglone and lawsone in the naphthaquinone group, alizarin, emodin, 1,8-dihydroxyanthraquinone, and anthraquinone in the anthraquinone group, and xanthone. Cultured cells were incubated with various concentrations of the quinones for four days in a 5% CO2 incubator, after which cell numbers were counted and significance of differences was analyzed by Student's t test. Anthraquinones and naphthaquinones used in these experiments were more effective than the monocyclic quinone. The 50% suppression dose was less than 12.5 micrograms/ml for them. The number of OH groups seemed to play an important role in the degree of the cell growth inhibition: anthraquinones with 2 or 3 OH groups were more effective than those with no OH group like, 9,10-dioxoanthracene and xanthone. In fact, anthraquinones with no OH group and xanthone were not significantly effective. Flow cytometric histograms revealed a specific pattern; that is, lawsone and juglone in the naphthaquinone group and alizarin and 1,8-dihydroxy-anthraquinone in the anthraquinone group blocked mainly the S phase, and emodin in the anthraquinone group blocked the G1 to S phase of the cell cycle.  相似文献   
104.
105.
Paradoxical inward rib cage movement in children is quantified by the labored breathing index (LBI) on the respiratory inductive plethysmography. Labored breathing index during rapid eye movement sleep (REMS) in 59 children without obvious sleep disordered breathing (SDB) declined with age, and decreased to the mature low level at 35 months of age. The LBI was also found to reflect well the severity of SDB. Paradoxical inward rib cage movement, which was quantified by LBI, is concluded to be an important finding in diagnosing SDB in child patients.  相似文献   
106.
Reduced vasodilatory capacity resulting from occlusive lesions of the major cerebral arteries may return to normal without surgical revascularisation. We aimed to determine prospectively the frequency and predictors of recovery of impaired haemodynamics as demonstrated by acetazolamide (ACZ) reactivity on single-photon emission computed tomography (SPECT). Vasoreactivity was measured by 123I-IMP SPECT with an ACZ challenge, in 37 medically treated patients with unilateral occlusive disease of the internal carotid or middle cerebral artery at an interval of 1–2 years. Each ACZ challenge test was analysed semiquantitatively by calculating the degree of increase in cerebral blood flow (CBF) asymmetry after ACZ administration (ΔAI). Vasodilatory capacity was abnormal initially in 20 patients (65 %); eight of whom (40 %) exhibited spontaneous normalisation on follow-up. Although the baseline characteristics did not differ significantly between patients with or without increase in reactivity, logistic regression analysis revealed that the initial ΔAI (P < 0.05) and the type of vascular lesion (stenosis or occlusion) (P < 0.05) correlated significantly with a return towards normal of reduced ACZ reactivity. Spontaneous improvement of impaired vasodilatory capacity may not be a rare phenomenon. We found that mild reduction in the initial ACZ reactivity and a stenosis, but not complete occlusion, were independent factors contributing to normalisation of impaired cerebral haemodynamics. Received: 12 October 1998/Accepted: 27 April 1999  相似文献   
107.
An 86-year-old male presented with progressive myelopathy due to retro-odontoid massive deposits of calcium pyrophosphate dihydrate (CPPD) crystals. Magnetic resonance imaging revealed a non-enhanced isointense extradural mass on the T1-weighted image and heterogeneously intense mass on the T2-weighted image. Computed tomography showed typical punctate and linear calcifications within the mass. The mass was resected via a lateral approach resulting in marked improvement of the symptoms. Histological examination revealed birefringent rhomboid crystals consistent with CPPD. CPPD deposition should be considered in the differential diagnosis of retro-odontoid extradural mass because surgical therapy is beneficial even for elderly patients.  相似文献   
108.
This report concerns percutaneous endoscopic gastrostomy (PEG) administered in the neurosurgical care unit to a patient with dysphasia. This reliable nutrition route has the major advantage of minimal surgical invasion and can be expected to become a standard nutritional method. Since patients with neurological disorders account for the majority of those who need PEG, neurosurgeons need to be aware of the importance of PEG.  相似文献   
109.
Cholesterol arterial embolization is a systemic disease resulting from cholesterol crystal embolization to multiple organs, including the kidney, skin, brain, eye, gastrointestinal tract and extremities. In general, it is associated with high morbidity and mortality, but no optimal treatment has yet been developed. In this paper, we report five patients with cholesterol atheroembolic renal failure. In three of the five patients, combined therapy with corticosteroids and plasma exchange was performed. The three patients survived. On the other hand, the two remaining patients died of multifactorial causes. In this report, the literature on steroid therapy for cholesterol atheroembolic renal disease is reviewed and the efficacy of combined therapy by use of corticosteroids and plasma exchange is evaluated.  相似文献   
110.
The role of the sentinel lymph node in gastrointestinal cancer   总被引:38,自引:0,他引:38  
Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers.  相似文献   
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