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11.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
12.
Patients with multiple system atrophy (MSA) present large changes in blood pressure (BP) due to autonomic disturbances. We analyzed how this change may influence dynamic cerebral autoregulation (DCA). Simultaneous recordings of arterial BP (Finapres) and middle cerebral artery (MCA) blood flow velocity (BFV) (transcranial Doppler) were performed in 10 patients with MSA (61 +/- 12 yr of age) and 12 healthy volunteers (61 +/- 11 yr of age): cerebral BFV response to oscillations in mean BP was studied in the supine position by cross-spectral analysis of mean BP and mean MCA BFV. The DCA was also studied during the decrease in BP the first seconds when standing up from a sitting position by the assessment of the cerebrovascular resistance index (CR; mean BP/mean MCA BFV ratio). The MCA BFV/BP cross-spectral analysis showed a phase for the mid-frequency band (0.07-0.2 Hz) significantly larger in MSA, suggesting more active autoregulation in response to larger changes in BP. Changes in CR reflecting the rate of autoregulation, when standing did not differ between the two groups. These data suggest that dynamic cerebral autoregulation is preserved in MSA.  相似文献   
13.
In Kobe University Hospital, a new method for endoscopic mucosal resection (EMR) using insulated‐tip electrosurgical knife (IT‐EMR) for early gastric cancer (EGC) was introduced from November 2001. To achieve an effective and safe IT‐EMR procedure, we use a high‐frequency surgical unit for cutting and coagulation (ERBOTOM ICC 200) with automatically controlled cutting mode (ENDOCUT). In this study, we show not only our results of IT‐EMR for EGC in comparison with those of the conventional strip biopsy method, but also the optimal conditions for the apparatus of a high‐frequency surgical unit to prevent complications such as bleeding and perforation.  相似文献   
14.
Background: For management of bowel obstruction due to colorectal cancer, endoscopic trans‐anal decompression technique has been first reported by Lelcuk et al. in 1986 using balloon dilatation technique. Since then, various types of trans‐anal decompression tubes have been clinically used for patients suffering from left side obstructing colorectal cancer as an emergent decompressing device. At present, two types of trans‐anal ileus tube (trans‐anal decompression tube) have been available for clinical use, but they have two main problems that are late colon perforations caused by the tip of the tube and tube obstruction by stool. Methods: Analysis on three late colon perforations experienced with the use of conventional devices drew possible improvements to make a trans‐anal ileus tube less harmful. To overcome the pitfalls inherent to conventional tubes, the author has developed an improved trans‐anal ileus tube with a balloon installed at the very end of the tube (‘balloon‐tipped type’) made of silicone, measuring 1200 or 1700 mm in total length and 22 Fr in outer diameter. It has been used for 12 cases with obstructing colorectal cancer etc. and its outcomes were compared with those obtained by the use of conventional trans‐anal ileus tube. Results: No late perforations have been encountered, but tube obstruction did occur in one of 12 cases. Conclusion: The new trans‐anal ileus tube with a balloon installed at the tip of ileus tube is considered to be safer and especially effective in preventing late colon perforation and tube obstruction.  相似文献   
15.
Background: Although bleeding is an unavoidable complication of endoscopic submucosal dissection (ESD), endoscopic hemostasis using an insulation‐tipped electrosurgical knife (IT) knife is impossible because an insulator is mounted at the tip of the knife. We have developed a new type of hood which could perform both coagulation and irrigation simultaneously. Methods: Our new device was fabricated by drilling a side hole in the cap portion of a conventional transparent hood followed by attaching a machined papillotomy knife to the exterior surface of the hole. Results: Our new hood was useful for hemorrhage during ESD using IT knife. Conclusions: With this method, endoscopic hemostasis using IT knife is easy, as hemostatic procedure can be performed under irrigation and coagulation using conventional endoscopy.  相似文献   
16.
AIMS: To establish all-cause and cause-specific death rates, and risk factors for mortality in insulin-treated diabetic individuals living in the province of Canterbury, New Zealand. METHODS: Insulin-treated diabetic subjects (n = 995) on the Canterbury Diabetes Registry were followed up over 15 years and vital status determined. Death rates were standardized and hazard regression was used to model the effects of demographic covariates on relative survival time. RESULTS: There were 419 deaths in 11 226.3 person-years of follow-up with a standardized mortality ratio (SMR) of 2.0 (95% confidence interval (CI) 1.8-2.2). Relative mortality was greatest for the group aged 0-29 years (SMR 3.0 (95% CI 2.4-3.7)). After controlling for diabetes duration and gender, a 10-year increment in age of onset was associated with a 33% decrease in relative hazard (95% CI 29-36%), indicating that excess mortality due to diabetes declines with rising age of onset. After controlling for age of onset and gender, each 10-year increment in duration of diabetes is associated with a 26% decrease in relative hazard (95% CI 24-29%), indicating that with longer survival the mortality hazard approaches the general population hazard. Relative mortalities were increased for cardiovascular, renal and respiratory disease, but not malignancy. Relative mortality from acute metabolic complications was increased in the subgroup with age of onset of diabetes < 30 years and requiring insulin within 1 year of diagnosis. CONCLUSIONS: Mortality rates are high for insulin-treated diabetic individuals relative to the general population.  相似文献   
17.
目的 检测亚硒酸钠是否能够削弱或解除顺铂对植物血球凝激素(PHA)刺激的人体外周血淋巴细胞的增殖抑制。方法 用顺铂和亚硒酸钠单独或联合处理PHA刺激的人体外周血淋巴细胞,顺铂(0.05,0.20,0.50mg/L)在细胞培养24h时加入,亚硒酸钠(0.05mg/L)在不同处理中分别在细胞培养开始时加入或与顺铂同时加入;培养72h后检测转化淋巴细胞的有丝分裂指数。结果0.05mg/L亚硒酸钠在培养开始时加入,PHA刺激转化的淋巴细胞有丝分裂指数较对照增长42.8%(P<0.05),与顺铂同时加入,有丝分裂指数增长13.7%(P>0.05)。0.05与0.20mg/L顺铂处理细胞,有丝分裂指数未发生显性改变,当顺铂剂量为0.50mg/L时,细胞有丝分裂指数较对照降低54.5%(P<0.001)。亚硒酸钠预处理细胞可以解除0.50mg/L顺铂所致的细胞增殖抑制,使有丝分裂指数恢复正常,但亚硒酸钠与顺铂同时加入时,被顺铂抑制的有丝分裂指数只能部分提高。结论0.05mg/L亚硒酸钠单独作用于淋巴细胞可直接促进细胞增殖,与顺铂联合处理细胞时,可降低顺铂毒性,拮抗顺铂的抗增殖作用。亚硒酸钠在细胞培养开始时加入培养体系效果更佳。  相似文献   
18.
The B cell functional response following ligation of surface(s) lgM is dependent upon the differentiation stage of the populationstudied: cross-linking slgM promotes proliferation of restingtonsillar follicular mantle (FM) B lymphocytes but induces apoptosisin the susceptible Epstein- Barr virus genome-negative Burkittlymphoma (BL) cell line Ramos (Ramos-BL). This study investigateswhether phosphatidylinositol-3-kinase (Pl3-kinase), which hasbeen reported to be intimately involved in the regulation ofcellular growth, plays a role in the regulation of these sig-promoted B cell responses, and uses the selective and irreversibleinhibitor of Pl3-kinase activity, wortmannin (Wm). In Ramos-BLB cells, at 8 h post-treatment, Wm triggers a transient increasein apoptosis of 16 ± 6.9% with a concomitant cellularloss of 16 ± 6.1% from the G1 phase of cell cycle; [3H]thymidineincorporation also decreases by 33 ± 5.0%, from 37,274c.p.m. ± 10% to 25,127 c.p.m. ± 4.0%. Moreover,at 72 h culture, Wm inhibits anti-lgM-induced FM B lymphocytelevels of [3H]thymidine incorporation typically by 47% and triggers80% apoptosis from the G0G1 phase of cell cycle. Ramos-BL Bcells exhibit high basal levels of Pl3-kinase activity, as determinedby immunoprecipitation with antibody to the p85 regulatory subunitof Pl3-kinase and 32P incorporation into phosphatidylinositol,which is not significantly affected by anti-lgM stimulation;by contrast, anti-lgM stimulates significant Pl3-kinase activityover negligible basal levels in FM B lymphocytes. Pre-treatmentwith Wm inhibits Pl3-kinase activity in both cell types. Takentogether these data indicate that in Ramos-BL B cells slgM-triggeredgrowth arrest and apoptosis is Pl3- kinase independent, whereasPl3-kinase activity is critical for slgM-triggered mitogenesisof FM B lymphocytes. Thus Pl3-kinase plays a pivotal role inthe regulation of both normal and neoplastic B lymphocyte progressionthrough the cell cycle, such that if this Pl3-kinase-dependentpathway is inhibited these cells default to apoptosis.  相似文献   
19.
We report on a Thai family with dominantly inherited malformation syndrome with upper limb anomalies, short stature, quadricuspid aortic valve, and minor craniofacial anomalies. The affected individuals comprised a mildly affected mother, a moderately affected daughter, and a most severely affected son. The daughter and son had short stature. The craniofacial abnormalities comprised frontal bossing, hypoplastic nasal bones, depressed nasal bridge, and broad nasal alae. The upper limb defects varies among the patients, ranging from radial ray defects in the mother through radial and ulnar ray defects with unilateral humeral hypoplasia in the daughter to radial ray defects with severe oligodactyly and bilateral humeral hypoplasia in the son. All patients in this family had hypoplasia of the shoulder girdle and resembled what is observed in many families with Holt‐Oram syndrome. Moreover, the son showed quadricuspid aortic valve with mild aortic regurgitation. However, the present family did not show any mutation of the TBX5 gene, a disease‐causing gene of Holt‐Oram syndrome. The present family deserves further investigation on other genes that play a role in the development of the upper limbs, particularly of radial rays. © 2002 Wiley‐Liss, Inc.  相似文献   
20.
Many important pharmaceutical agents, including vancomycin, bleomycin, cyclosporin, and several antibiotics, are produced by non‐ribosomal peptide synthetase (NRPS) enzymes in microorganisms. The NRPS pathway produces an extensive library of products using multienzyme complexes acting in an assembly‐line fashion. Engineering an NRPS system to produce an even greater variety of products, some of which may also have beneficial therapeutic value, would be an enormous advantage. Several approaches have been successful in generating novel NRPS products: mutational biosynthesis during which nonnatural substrates are fed to an organism; domain and module swapping between different species to generate hybrid enzymes; and rational site‐directed mutagenesis, based either on phylogeny or computational prediction, intended to switch substrate specificity and produce altered products. This review will highlight the progress in these areas and describe research in the future that will extend the capacity for re‐engineering NRPS systems. Drug Dev. Res. 66:9–18, 2006. © 2006 Wiley‐Liss, Inc.  相似文献   
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