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101.
The purpose of this study was to evaluate the effect of pre-treatment with ketamine on the reduction of pain during injection of propofol in adult patients. We conducted a prospective, randomized, double-blinded trial. Forty-three patients were randomly allocated to one of two groups according to the agents administered before hand; Group C, normal saline 2 ml and Group K, 1% ketamine 2 ml. The pain on injection was rated as none, mild, moderate, or severe. Sixty-eight percent of patients in the C group experienced pain, while 33% of patients experienced pain in the K group. Thirty-six percent of patients in the C group complained moderate to severe pain but only 9% of patients in the K group. The mechanisms of prevention by ketamine of the pain on propofol-injection could not be clarified from our study, but it may be related to central effects of ketamine. In conclusion, ketamine pre-treatment before propofol administration significantly reduces incidence and severity of pain associated with propofol injection.  相似文献   
102.
A series of shinjulactone C (1) derivatives (2-8) were synthesized and evaluated for their anti-tumor promoting effects against Epstein-Barr virus early antigen activation introduced by 12-O-tetradecanoylphorbol-13-acetate in Raji cells. The succinate and 3',3'-dimethylsuccinate derivatives of 1 exhibited higher inhibitory effects than 1. From the point of view of structure-activity relationships, the succinate derivatives (2, 4) demonstrated better potency than the glutarate derivatives (3, 5-8). As substituted moieties of 3'-position became bulky, the inhibitory effects of the glutarate derivatives (7, 8) significantly decreased.  相似文献   
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Miyamoto R  Uzawa N  Nagaoka S  Nakakuki K  Hirata Y  Amagasa T 《Cancer》2002,95(10):2152-2159
BACKGROUND: Amplification of chromosome 11q13 is a frequent event in carcinogenesis of the head and neck squamous cell carcinomas including oral carcinoma. METHODS: Fluorescence in situ hybridization (FISH), using a BAC clone specific for the cyclin D1 gene (CCND1), was performed on specimens obtained by fine-needle aspiration biopsy (FNAB) from 50 patients with primary oral squamous cell carcinomas (OSCCs.). RESULTS: The CCND1 numerical aberration was identified in 21 (42.0%) of 50 patients with primary OSCCs. The CCND1 amplification was determined in 16 (32.0%) of these patients. Immunohistochemical staining revealed that all 21 tumors showing the CCND1 numerical aberration overexpressed the CCND1 protein. The CCND1 numerical aberration was associated significantly with histopathologic grading (P = 0.032), the mode of invasion (P = 0.047), the presence of cancer cells at the resection margin (P = 0.033), pathologic lymph nodestatus (P = 0.045), disease recurrence (P = 0.004), and survival (P = 0.004). The disease-free and overall survival period of patients with the CCND1 numerical aberration was significantly shorter than that of patients without the CCND1 numerical aberration (P = 0.0016 and P = 0.0019, respectively). Moreover, a multivariate analysis showed that the CCND1 numerical aberration retained an independent prognostic value. CONCLUSIONS: The CCND1 numerical aberration is useful both as a prognostic indicator that is independent of the TNM classification, and an indicator to assist in determination of the appropriate treatment for patients with OSCCs. Analysis of the CCND1 numerical aberration using FISH on FNABs may be a useful and practical method for predicting aggressive tumors, recurrence, and clinical outcome in patients with OSCCs.  相似文献   
105.
In Schwann cells, the transmembrane glycoprotein beta-dystroglycan comprises the dystroglycan complex, together with the extracellular glycoprotein alpha-dystroglycan, which binds laminin-2 (alpha 2/beta 1/gamma 1), a major component of the Schwann cell basal lamina. To provide clues to the biological functions of the interaction of the dystroglycan complex with laminin-2 in peripheral nerves, we investigated the expression of beta-dystroglycan and the laminin-alpha 2 chain in rat sciatic nerve during development by immunoblot, immunofluorescence, and immunoelectron microscopic studies. The expression of beta-dystroglycan and the laminin-alpha 2 chain in the rat sciatic nerve was low and not confined to the Schwann cell outer membrane from embryonic day 18 to birth, when there was only an immature basal lamina assembly and no compact myelin formation by Schwann cells. However, the expression of these proteins increased markedly and became clearly localized to the Schwann cell outer membrane between birth and postnatal day 7, when both basal lamina assembly and compact myelin formation by Schwann cells progressed rapidly. From postnatal day 7 to adult, there was no remarkable change in the expression of these proteins. Our results support the hypothesis that the dystroglycan complex functions as an adhesion apparatus, binding the Schwann cell outer membrane with the basal lamina, and suggest that the dystroglycan complex plays a role in Schwann cell myelination through its interaction with laminin-2.  相似文献   
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INTRODUCTION: Transient T wave changes after cessation of preexcitation have been attributed to cardiac memory. However, there have been no reports on the effects of long-term cardiac memory on repolarization dispersion before and after catheter ablation in patients with Wolff-Parkinson-White (WPW) syndrome. METHODS AND RESULTS: We investigated 47 patients with an accessory pathway (AP; 24 manifest left-sided, 14 manifest right-sided, and 9 concealed left-sided). Repolarization dispersion was analyzed by two methods, recovery time (RT) dispersion and newly proposed T wave width (WT), from 87-lead body surface maps before, 1 day after, and 7 days after catheter ablation. RT dispersion and WT were significantly correlated before, 1 day after, and 7 days after catheter ablation (r = 0.78). In patients with preexcitation, RT dispersion and WT increased significantly (P < 0.05) 1 day after catheter ablation (178 +/- 32 msec and 172 +/- 30 msec) compared with those before (154 +/- 24 msec and 156 +/- 18 msec) and 7 days after catheter ablation (147 +/- 19 msec and 156 +/- 16 msec), respectively. However, there were no significant changes in RT dispersion and WT before and after catheter ablation in concealed WPW syndrome. CONCLUSION: The findings suggest that the abrupt changes in activation sequence increase repolarization dispersion in the presence of previous cardiac memory, and that the dispersion decreases days or weeks after alteration of activation sequence by catheter ablation, with development of new cardiac memory in patients with manifest WPW syndrome.  相似文献   
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109.
PURPOSE: To examine the changes of taurine concentrations in blood and skeletal muscles after transient exercise. METHODS: Rats were placed on a treadmill set at 25 m.min-1. The animals were divided into four groups: control (no exercise) and exercise groups 1, 2, and 3. The exercise duration for groups 1, 2, and 3 was 30, 60, and 100 +/- 12.5 min (to exhaustion: mean +/- SD), respectively. We examined the plasma concentrations of taurine and lactate, the serum concentrations of sodium and chloride ions, as well as the skeletal muscle taurine content in the soleus (slow-twitch fiber dominant type), gastrocnemius (slow- and fast-twitch fiber mix type), and plantaris and extensor digitorum longus (fast-twitch fiber dominant type) muscles. RESULTS: Although the plasma taurine concentration was not affected by the increased exercise duration, that in skeletal muscles was significantly decreased. The gastrocnemius and plantaris muscles from the exercise group 3 had a significantly lower concentration of taurine than those of the control group. The extensor digitorum longus taurine concentration from the different exercise groups was significantly decreased compared with that from the control group. However, there was no significant difference among the exercise groups. CONCLUSION: Taurine concentration was decreased in all skeletal muscles after exercise, regardless of the duration. Moreover, this decrease was specific to fast-twitch dominant fibers. However, under these conditions, the plasma taurine concentration remained unchanged.  相似文献   
110.
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