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51.
Sclerosing cholangitis: CT findings   总被引:5,自引:0,他引:5  
The value of computed tomography (CT) in the detection of primary sclerosing cholangitis (PSC) in the intrahepatic and extrahepatic biliary systems was assessed by comparing CT scans of 20 cases of PSC with cholangiographic findings. In 16 of 19 cases of extrahepatic duct disease demonstrated with cholangiography, CT demonstrated abnormalities of the common hepatic duct, or bile duct, including duct stenosis, mural nodularity, duct dilatation, wall thickening, and mural enhancement. CT demonstrated intrahepatic disease in all 20 cases, including duct dilatation, duct stenosis, pruning, and beading. CT was superior to cholangiography in characterization of the status of the intrahepatic duct system in 11 of 20 cases. In addition, CT demonstrated extrabiliary complications of PSC in 12 cases and superimposed cholangiocarcinoma in three cases. While cholangiography remains the standard for diagnosis and follow-up of PSC, CT can provide valuable information about the extent and complications of the disease.  相似文献   
52.
目的 总结直视下尿道内切开术(direct vision internal urethrotomy,DVIU)治疗尿道狭窄的经验.方法 回顾性分析1990年6月至2010年6月20年间DVIU治疗尿道狭窄或闭锁患者361的临床资料.年龄16~72岁,平均38岁.病程3~78个月,平均16个月.狭窄或闭锁长度0.2~2.0 cm,平均1.1 cm.狭窄长度≤1.0 cm 238例,其中≤0.5 cm 63例(组1),0.6~1.0 cm 175例(组2),瘢痕厚度≤1.0 cm 148例,>1.0 cm 90例;狭窄长度1.1~2.0 cm 123例,其中1.1~1.5cm 85例(组3),1.6~2.0 cm 38例(组4),瘢痕厚度≤1.0 cm 44例,>1.0 cm 79例.结果 361例中手术失败3例.320例获随访,随访时间12~120个月,平均42个月.因狭窄复发而接受开放手术174例(54.4%),4组中转开放手术率分别为3.3%、49.7%、83.3%和97.1%.狭窄长度≤1.0cm者获随访207例,其中瘢痕厚度≤1.0 cm转开放手术27.2%(37/136),瘢痕厚度>1.0 cm转开放手术60.6%(43/71).狭窄长度>1.0 cm者获随访113例,其中瘢痕厚度≤1.0 cm转开放手术78.6%(33/42),瘢痕厚度>1.0 cm转开放手术84.5%(60/71).结论 当尿道狭窄长度≤0.5 cm时,DVIU术后转开放手术的比例明显减少;狭窄长度≤1.0 cm,瘢痕厚度≤1.0 cm者,DVIU也可获较好疗效.
Abstract:
Objective To summarize the experience and evaluate the efficacy of treatment of urethral stricture using direct visual internal urethrotomy (DVIU).Methods The clinical data of 361 patients (age range 16 -72 years, mean age 38 years) with urethral stricture who underwent urethrotomy from 1990 to 2010 was retrospectively analyzed.The disease course ranged from three months to 78 months with a mean of 16 months.The stricture length ranged from 0.2 to 2.0 cm (mean 1.1 cm).Stricture length was split into four main groups:stricture length≤0.5 cm in 63 (group 1 ), stricture length ranging between 0.6 and 1.0 cm in 175 ( group 2), stricture length ranging between 1.0 and 1.5 cm in 85 ( group 3 ) , and stricture length ranging between 1.6 and 2.0 cm in 38 ( Group 4).Of the 238 patients with length less than 1.0 cm there were 148 who's scar thickness were less than 1.0 cm, and 90 who's scar thickness were greater than 1.0 cm.Of the 123 patients with length less than 2.0 cm there were 69 who's scar thickness was less than 1.0 cm, and 54 who's scar thickness was greater than 1.0 cm.Results Three patients with DVIU failed because of long occlusion and false passage.Three hundred and twenty patients were followed-up from 12 to 120 months (mean:42).Re-openiag procedures were performed on 174 patients (54.4%) due to recurrence.The re-openiag procedure rate was 3.3%, 49.7%, 83.3% and 97.1% in Group1, Group2,Group3 and Group4, respectively.On the basis of scar thickness, of the 207 patients with stricture length less than 1.0 cm, 38 of 136 patients (27.9%) with scar thickness less than 1.0 cm underwent opening operation, and 43 of 71 patients (60.6%) with scar thickness more than 1.0 cm underwent opening operation.One hundred and thirteen patients with stricture length more than 1.0 cm, 33 of 42 patients (78.6%) with scar thickness less than 1.0 cm underwent opening operation, and 60 of 71 patients (84.5%) with scar thickness more than 1.0 cm underwent opening operation.Conclusions Good efficacy can be achieved in patients whose urethral stricture length is less than 0.5cm or whose stricture length and scar thickness is less than 1.0 cm using DVIU.  相似文献   
53.
 目的 分析超声各特征性影像表现在乳腺浸润性导管癌中的诊断价值。方法 选取解放军总医院第六医学中心 2018-01至2019-12两年内收治的 135例乳腺浸润性导管癌患者纳入本研究,分析乳腺浸润性导管癌的超声影像特征、体检自检发现率以及淋巴结转移与病变大小、位置的相关性。结果 (1)单因素分析显示:形态不规则(91.11%)、边界不清楚(64.44%)、血流信号(44.44%)、微钙化(37.78%)、纵横比>1(17.78%)、后方回声衰减(15.56%)超声诊断指标,与浸润性导管癌的诊断具有相关性;(2)与其他三个象限相比较,内上象限浸润性导管癌更容易被患者自检发现,占自检发现病例的34.93%;(3)内上象限及外上象限的浸润性导管癌更容易发生淋巴结转移(转移率为:内上:25.53%,内下:0.00%,外上:64.70%,外下:11.76%);(4)对<3 cm的浸润性导管癌,其大小与腋窝淋巴结的转移没有相关性。结论 超声表现以形态不规则在乳腺浸润性导管癌中的发生率最高,且在早期病变中即表现出来;乳腺病变的自检检出率、乳腺癌淋巴转移率均与乳腺病变的大小和位置密切相关。  相似文献   
54.
55.

Introduction

The retrojugular approach for carotid endarterectomy (CEA) has been reported to have the advantages of shorter operative time and ease of dissection, especially in high carotid lesions. Controversial opinion exists with regard to its safety and benefits over the conventional antejugular approach.

Methods

A systematic review of electronic information sources was conducted to identify studies comparing outcomes of CEA performed with the retrojugular and antejugular approach. Synthesis of summary statistics was undertaken and fixed or random effects models were applied to combine outcome data.

Findings

A total of 6 studies reporting on a total of 740 CEAs (retrojugular approach: 333 patients; antejugular approach: 407 patients) entered our meta-analysis models. The retrojugular approach was found to be associated with a higher incidence of laryngeal nerve damage (odds ratio [OR]: 3.21, 95% confidence interval [CI]: 1.46–7.07). No significant differences in the incidence of hypoglossal or accessory nerve damage were identified between the retrojugular and antejugular approach groups (OR: 1.09 and 11.51, 95% CI: 0.31–3.80 and 0.59–225.43). Cranial nerve damage persisting during the follow-up period was similar between the groups (OR: 2.96, 95% CI: 0.79–11.13). Perioperative stroke and mortality rates did not differ in patients treated with the retrojugular or antejugular approach (OR: 1.26 and 1.28, 95% CI: 0.31–5.21 and 0.25–6.50).

Conclusions

Currently, there is no conclusive evidence to favour one approach over the other. Proof from a well designed randomised trial would help determine the role and benefits of the retrojugular approach in CEA.  相似文献   
56.
57.
Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
58.
目的通过构建以MDR1启动子为启动序列的双荧光素酶报告基因系统并进行活性分析,为MDR1基因表达的单靶点调控研究和逆转剂的筛选提供一种有效的方法。方法从HCT-8细胞中提取DNA并克隆含有MDR1基因启动子中Y—box序列。将该序列重组到萤光素酶报告基因载体pGL-3.Basic的启动区域中,从而构建报告基因载体pGL-MDR1。将pGL-MDR1和pRL-TK载体共转染到HCT-8和HCT-8/VCR细胞中。通过调节不同载体的比例来优化转染效率。利用MDRI基因激活剂(热诱导)和抑制剂(EGCG)等处理来分析其启动转录活性受外界因素的影响。结果通过直接测序法验证了pGL-MDR1含有MDR1基因启动子Y—box序列且没有出现碱基突变。在pGL-MDR1和pRL-TK的转染比例为5:5时,转染效率最高并具有最高的萤光素酶活性。通过MDR1基因激活处理后表现为时间依赖性地激活MDR1基因的表达,而MDR1基因抑制剂的作用则相反。结论MDR1启动子为启动序列的双荧光素酶报告基因系统建立成功。该系统不但可以用于研究活体生物发光成像和MDRI基因表达的机理,而且可用于单靶点的多药耐药抑制剂的筛选。  相似文献   
59.
Huntington disease (HD) is caused by an expanded CAG repeat sequence in the HD gene. Although the age at onset is correlated to the CAG repeat length, this correlation only explains approximately half of the variation in onset age. Less variation between siblings indicates that the variation is, in part, explained by genetic modifiers. We analyzed polymorphic loci within or close to the HD gene on the HD chromosome in Danish HD patients. We found one specific haplotype segregating with later age at onset, compared with patients with similar CAG repeat length and another haplotype. The nine Danish families in the study carrying this haplotype most likely have a common founder. Several of the polymorphic loci displayed alleles that may be specific to the late-onset haplotype, implicating that from this study we cannot determine which of the loci tested (or other polymorphic loci in this chromosomal area) do in fact contain genetic modifiers of age at onset.  相似文献   
60.
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