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41.
Background: We evaluated the endoscopic microvascular architecture of the gastric mucosa in portal hypertension patients using the prototype of narrow band imaging (NBI). Material and Methods: The study included 103 Helicobacter pylori‐negative patients with chronic liver disease (22 without portal hypertension (group 1), 81 with portal hypertension (group 2)). Results: (i) Abnormality of collecting venules, reddening mucosa, red spots, a mosaic‐like pattern, and gastric antral vascular ectasia (GAVE) were observed on the gastric mucosa, and an obscure change in collecting venules (73% vs 14%; P < 0.001), reddening mucosa (49% vs 5%; P < 0.001), red spots (36% vs 5%; P < 0.01) and a mosaic‐like pattern (40% vs 5%; P < 0.01) were more frequently observed in group 2 than in group 1. (ii) On magnifying endoscopy with NBI, the mucosa with an obscure change in collecting venules was demonstrated as dilation of the capillaries surrounding the gastric pits in various degrees, and reddening mucosa was observed as extended and swollen gastric pits and various degrees of dilated and convoluted capillaries surrounding the gastric pits. Red spots were demonstrated as extended and swollen gastric pits, dilated and convoluted capillaries surrounding the gastric pits, and intramucosal hemorrhage around these capillaries. GAVE was recognized as partial and marked dilatation of the capillaries surrounding the gastric pits. Conclusion: Abnormality of collecting venules, swelling of gastric pits, dilatation of capillaries surrounding the gastric pits, intramucosal hemorrhage around capillaries, and partial and marked dilatation of the capillaries were observed on the gastric mucosa in portal hypertension patients. 相似文献
42.
成人门静脉海绵样变性的诊断和治疗 总被引:5,自引:1,他引:4
目的 探讨成人门静脉海绵样变性的诊断方法和治疗。方法 对 31例成人门静脉海绵样变性患者的临床资料进行回顾性分析。结果 31例患者术前均有出血史 ,术前均经超声检查提示肝脏正常及门静脉海绵样变性 ,经脾穿刺门静脉造影或选择性肠系膜上动脉造影确诊。 12例行脾动脉结扎、胃冠状静脉及分支结扎、肠 腔C型架桥术 ,1例行脾 肾静脉架桥术。 8例已切脾断流后再出血患者 ,结扎冠状静脉主干后 ,6例行肠 腔C型架桥术 ,1例行肠系膜下静脉 下腔静脉C型架桥术 ,1例因静脉曲张和出血部位在空肠上段而行空肠节段切除术。 6例行脾 腔架桥术 ,2例行改良脾 肺固定术 ,脾 肾架桥术和门静脉 下腔静脉架桥术各 1例 ,1例行脾切除加贲门周围血管离断术。术后随访 6个月~ 4年 (随访率 10 0 % ) ,食管胃底曲张静脉均减轻或消失 ,无再出血和肝性脑病发生。结论 多普勒超声检查和经皮脾穿刺门静脉造影是诊断本病的理想方法 ;门 体分流术加门 奇断流术是治疗本病的最佳选择。 相似文献
43.
We describe what we believe to be the first reported case of intragastric erosion and migration to the jejenum of a laparoscopically
inserted gastric band, 3 months after the original bariatric surgery was performed. This had caused ulceration and necrosis
of the small bowel as the tension in the port tubing had caused the bowel to become concertinaed over it and resulted in a
cheese-wire effect through the jejunal convolutions. As bariatric surgery becomes more common, patients with complications
of their procedure may present to the general surgeon as an emergency. We recommend early intervention in patients with gastric
erosion. 相似文献
44.
目的探讨胃饲乙醇预处理对肝脏缺血再灌流损伤的影响,并初步评价其预处理的可行性。方法40%乙醇胃饲Wistar大鼠。分组:①大鼠36只,随机分6组:A组8g/kg、B组7g/kg、C组6g/kg、D组5g/kg、E组4g/kg、正常组0g/kg;以中毒症状及肝组织病理为指标,判定大鼠乙醇急性中毒剂量。②大鼠78只,随机分为4组:正常对照组(N)、单纯乙醇组(E)、单纯缺血组(ISCH)、胃饲乙醇预处理组(EPC);采用尾叶转流下的肝缺血模型,于再灌流3、6、12、24h留取标本。结果急性胃饲乙醇≤5g/kg预处理后,动物中毒症状轻,无死亡;乙醇预处理可以在一定程度上减轻肝脏90min的缺血再灌流损伤。结论适当剂量的乙醇胃饲预处理是一种安全的预处理措施,有望成为增强肝脏对缺血再灌流损伤耐受性的一种较好的预处理方式。 相似文献
45.
应用自动化图象分析仪对131个胃粘膜肠型病灶(单纯性肠化27个;异型增生:轻度30,中度35个,重度20个;肠型胃癌19个)进行定量分析。以单个腺管内细胞核总面积与细胞面积之比(ING)作为反映细胞核大小、数量及覆层排列程度的客观定量指标。结果发现:单纯性肠化(对照组)0.165±0.025,轻度异型增生0.21±0.023,中度异型增生0.259±0.026,重度异型增生0.32±0.028,分化型胃癌0.371±0.052,各组ING值呈正态,各组间的均值有非常显著的差异(P<0001)。因而,ING可作为胃粘膜癌前病变诊断的指标。 相似文献
46.
目的分析和总结残胃癌的外科诊断、治疗及预后情况。方法对1990年以来收治的35例残胃癌的发病率、临床表现、治疗情况和预后进行回顾性分析。结果首次胃切除以胃溃疡为主,占65.7%,首次手术BillrothⅡ式占82.9%(29/35)。残胃癌早期缺乏特异的症状,主要为上腹部隐痛不适,首次手术距临床诊断残胃癌的间隔时间平均为16.3年。本组残胃癌手术切除率及根治性切除率分别为77.1%和54.3%,根治性切除患者1、3、5年生存率分为78.9%、52.6%、36.8%,Ⅰ期、Ⅱ期患者的5年生存率为72.7%。结论胃良性病行手术治疗时以BillrothⅠ式为首选,定期胃镜检查是早期诊断残胃癌的关键,根治性切除是治疗残胃癌的有效方法及影响残胃癌预后的重要因素。 相似文献
47.
L. E. Sanders 《Surgical endoscopy》1995,9(6):724-727
We present two cases in which complication of a Meckel's diverticulum were dealt with, and in one case diagnosed using the laparoscope. One was a large bleeding diverticulum containing ectopic gastric mucosa, with the diagnosis suggested preoperatively, confirmed laparoscopically, and the pathology resected extracorporeally. The second was a partial intermittent small-bowel obstruction due to torsion around the mesodiverticular band, diagnosed and resected via the laparoscope. The literature of Meckel's diverticula and complications is reviewed, with open and laparoscopic treatment options. Although uncommon, many cases of Meckel's diverticulum may be quite suitable for laparoscopic diagnosis and treatment. 相似文献
48.
The cardiac effects of terfenadine after inhibition of its metabolism by grapefruit juice 总被引:2,自引:0,他引:2
C. P. Clifford D. A. Adams S. Murray G. W. Taylor M. R. Wilkins A. R. Boobis D. S. Davies 《European journal of clinical pharmacology》1997,52(4):311-315
Objective: To determine whether the pharmacokinetics and electrocardiographic pharmacodynamics of terfenadine are affected by the concomitant
administration of grapefruit juice.
Methods: Six healthy volunteers were recruited for a balanced cross-over study. Each volunteer received 120 mg terfenadine 30 min
after drinking 300 ml of either water or freshly squeezed grapefruit juice. The alternative treatment was administered on
the second study day 2 weeks later. Measurements of the area under the terfenadine plasma concentration-time curve (AUC),
maximum terfenadine concentration (Cmax) and the time to maximum concentration (tmax) were made, and the corrected QT (QTc) interval was measured from the surface electrocardiogram.
Results: Terfenadine was quantifiable in plasma in all 6 subjects on both study days for up to 24 h post-dosing. The AUC of terfenadine
was significantly increased by concomitant grapefruit administration (median values 40.6 vs 16.3 ng · ml−1 · h), as was the Cmax (median values 7.2 vs 2.1 ng · ml−1). The tmax was not significantly increased and there was no significant change in the median QTc interval despite the increased terfenadine
levels. The 95% confidence interval for the difference in the change in QTc interval at Cmax was −13 to +38 ms.
Conclusion: Administration of grapefruit juice concomitantly with terfenadine may lead to an increase in terfenadine bioavailability,
but the increase observed in this study did not lead to significant cardiotoxicity in normal subjects. However, this does
not exclude the risk of cardiotoxicity in high-risk subjects given greater doses of grapefruit juice over longer periods of
time.
Received: 14 October 1996 / Accepted in revised form: 10 December 1996 相似文献
49.
Shaping ability of the M4 handpiece and Safety Hedstrom Files in simulated root canals 总被引:1,自引:0,他引:1
A. LLOYD A. JAUNBERZINS A. DHOPATKAR S. BRYANT P. M. H. DUMMER 《International endodontic journal》1997,30(1):16-24
The aim of this study was to assess the shaping ability of the M4 reciprocating handpiece and Safety Hedstrom files in simulated canals. A total of 40 simulated canals of various angles and positions of curvature were prepared with an M4 handpiece using Safety Hedstrom files oriented with the ground, flattened surface towards the inner aspect of the curve. A standard regimen was adopted throughout. Pre- and post-operative longitudinal images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount and location of resin material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Preparation time varied significantly (P<0.001) between the canal types; overall, 20° canals were prepared more quickly than 40° canals. Zips and elbows were observed in 16 out of the 40 canals with most (11) being created in 40° specimens. Ledges were found in 19 canals and perforations in only 1. There were no significant differences between canal shapes for these aberrations. Excessive removal of material from the inner aspect of the canal at the curve to create a danger zone was found in 20 canals, but only in those with 40° curves. Significant differences in total canal width between the canal types were seen at the zips (P<0.05), elbows (P<0.05) and danger zones (P<0.001). Transportation at the danger zones varied significantly (P<0.001) between canal types. Under the conditions of this study, the M4 handpiece and Safety Hedstrom files created hour-glass preparations in a substantial proportion of canals. In reality, the Safety Hedstrom file with its one flattened surface was ineffective at reducing removal of material along the inner aspect of canal curves in severely curved specimens and clearly has the potential to create strip perforations in teeth. 相似文献
50.
Francesco Bertoni Giovanni Cazzaniga Giovanna Bosshard Enrico Roggero Renzo Barbazza Michele De Boni Carlo Capella Ennio Pedrinis Franco Cavalli rea Biondi & Emanuele Zucca 《British journal of haematology》1997,97(4):830-836
Gastric MALT lymphoma usually develops from chronic gastritis, the vast majority of which (>90%) is associated with Helicobacter pylori infection. We sequenced the third complementarity determining region (CDR3) of immunoglobulin heavy chain genes in 19 gastric MALT lymphoma clones to determine the pattern of variable (V), diversity (D) and joining (J) gene utilization during immunoglobulin gene rearrangement.
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma. 相似文献
DNA was extracted from paraffin-embedded sections and the rearranged CDR3 regions were amplified using a semi-nested polymerase chain reaction (with primers complementary to the conserved framework-three segment of the variable region [FR3A] and J regions). The DNA used for cloning and sequencing was obtained after purification of monoclonal bands excised from polyacrylamide gels. The N-D-N region specific to each clone was compared with known germline D sequences.
Similarly to that observed in normal and leukaemic B cells, our series of gastric MALT lymphomas showed apparent preferential utilization of genes from the DXP family. In two cases no similarity between the CDR3 nucleotide sequences of the neoplastic clones and the known germline D sequences could be found. In 10/19 analysed alleles the lymphoma B-cell clones appeared to contain two D gene segments (D-D recombination), a rare occurrence in normal individuals but one which has been described as a significant event in the determination of idiotype expression and antigen-binding affinity. Remarkably, despite the use of different D and J segments, the resultant amino acid sequences matched in two patients, suggesting the presence of a common selecting antigen.
The observed pattern of D gene rearrangement suggests that MALT lymphoma B-cell clones have undergone antigen selection, which seems to indicate that the antigen stimulation plays a pivotal role in the development of the lymphoma. 相似文献