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101.
Colonoscopy is an integral part of the clinician armamentarium in the diagnosis of colorectal cancer and its precursor, the adenoma. Polypoid lesions when identified can be excised at colonoscopy and in turn reduce the risk of colorectal cancer. We prospectively evaluated the yield of colorectal cancer and adenomatous polyps by indication for colonoscopy over a one-year period. A total of 375 colonoscopies were carried out. The more common indications of colonoscopy were rectal bleeding, abdominal pain, surveillance of colorectal cancer and altered bowel habit. The highest yield for cancer was for rectal bleeding with 12.5% while surveillance of patients with a history of polyps yielded the highest percentage of new polyps. We conclude that rectal bleeding as an indication for colonoscopy yielded the highest number of cancers.  相似文献   
102.

Objective

To compare the efficacy of suprapapillary and transpapillary methods of transhepatic biliary metallic stent placement in malignant biliary strictures and to specify the indications of each method applied.

Materials and Methods

Stents were placed in 59 patients. Strictures were categorized as type A (within 3 cm of the ampulla, n = 27), type B (over 3 cm from ampulla, n = 7), type C (within 3 cm of the bending portion, n = 9), or type D (over 3 cm above the bending portion, n=16). The stenting method was suprapapillary in 34 cases and transpapillary in 25. The rates of initial and long-term patency and of early recurrence were compared.

Results

Initial patency rates for the suprapapillary and transpapillary methods were 1/7 (14.3%) and 20/20 (100%) respectively for type A (p < 0.0001), 4/5 (80.0%) and 2/2 for type B, 3/7 (42.9%) and 2/2 for type C, and 15/16 (93.8%) and 0/0 for type D. Early recurrence rates were 7/30 (23.3%) using the suprapapillary method and 4/29 (13.8%) using the transpapillary method (p = 0.51). The long-term patency rate did not differ significantly according to either type (p = 0.37) or method (p = 0.62).

Conclusion

For good initial patency, the transpapillary method is recommended for strictures of the distal extrahepatic duct near the ampulla and just above the bending portion. Long-term patency is not influenced by the stenting method employed.  相似文献   
103.
Purpose: To investigate the relationships between the axonal sprouting and target neurotization by central neurons after nerve heterocon-nection. Methods: Unilateral (right) vagal-hypoglossal nerve anastomosis (VHA) was performed in adult cats. Following 3-315 days postoperation (dpo), quantitative analyses and ultrastructural changes in the proximal portion of the vagal-hypoglossal heteroconnected nerve as well as the time course of neuronal regeneration were studied. Along with this, horseradish peroxidase (HRP) retrograde tracing technique was used to label the neurons of dorsal motor vagal nucleus (DMV) and nucleus ambiguus (NA) to ascertain if target neurotization was established. Results: The contralateral (left) intact vagus nerve proximal to the level of ansa cervicalis showed an average of 33 +/- 1 myelinated and 74 +/- 4 unmyelinated axons in 727 &mgr;m(2) sectional area of the nerve. In the heteroconnected nerve at the corresponding level just proximal to the anastomosis site, there was a marked increase in the number of small axons sprouting from the unmyelinated nerve fibers between 18 and 25 dpo. The number of these axonal sprouts appeared to decline at 32 dpo but its increase of 131 % was sustained until the late regeneration stage at 315 dpo when compared with the contralateral nerve serving as a control. The mean number of myelinated axons per area unit (727 &mgr;m(2)) was reduced to 18 at 3 dpo but was immediately restored to the normal range at 7 dpo. The retrograde labelling of neurons in both the DMV and NA was first detected at 22 dpo and was progressively increased peaking by about 67 dpo. Conclusions: We conclude that compared with the unmyelinated axons, the myelinated axons may acquire a superior interaction with the new target. Furthermore, the postoperative neurotization of tongue muscles may initiate and facilitate the retraction of the redundant axonal sprouts.  相似文献   
104.
105.
Angiogenesis is an essential process in the development, growth, and metastasis of malignant tumors including lung cancer. DNA sequence variations in the vascular endothelial growth factor (VEGF) gene may lead to altered VEGF production and/or activity, thereby causing interindividual differences in the susceptibility to lung cancer via their actions on the pathways of tumor angiogenesis. To test this hypothesis, we investigated the potential association between three VEGF polymorphisms (-460T > C, +405C > G, and 936C > T)/haplotypes and the risk of lung cancer in a Korean population. VEGF genotypes were determined in 432 lung cancer patients and 432 healthy controls that were frequency matched for age and sex. VEGF haplotypes were predicted using Bayesian algorithm in the phase program. Compared with the combined +405 CC and CG genotype, the +405 GG genotype found associated with a significantly decreased risk of small cell carcinoma [SCC; adjusted odds ratio (OR), 0.36; 95% confidence interval (95% CI), 0.17-0.78]. The 936 CT genotype and the combined 936 CT and TT genotype were also associated with a significantly decreased risk of SCC compared with the 936 CC genotype (adjusted OR, 0.47; 95% CI, 0.26-0.85 and adjusted OR, 0.44; 95% CI, 0.24-0.80, respectively). Haplotype CGT was associated with a significantly decreased risk of SCC (adjusted OR, 0.39; 95% CI, 0.18-0.87), whereas haplotype TCC conferred a significantly increased risk of SCC (adjusted OR, 1.63; 95% CI, 1.14-2.33). None of the VEGF polymorphisms studied significantly influenced the susceptibility to lung cancer except SCC. However, haplotypes TCT and TGT were significantly associated with the risk of overall lung cancer, respectively (adjusted OR, 0.38; 95% CI, 0.25-0.60 and adjusted OR, 3.94; 95% CI, 2.00-7.76, respectively). These effects of haplotypes TCT and TGT on lung cancer risk were observed in three major histologic types of lung cancer. These results suggest that the VEGF gene may be contribute to an inherited predisposition to lung cancer.  相似文献   
106.
107.
AIM: To investigate the incidence of abrupt visual loss and its associated factors, during anti-vascular endothelial growth factor (VEGF) treatment for type 3 neovascularization. METHODS: This retrospective study included 137 eyes that were newly diagnosed with type 3 neovascularization. All eyes were treated with anti-VEGF therapy. Abrupt visual loss was defined as loss of 5 or more lines in best-corrected visual acuity (BCVA) in comparison to the previous visit. The incidence and timing of abrupt visual loss as well as the factors associated with it, were determined. In addition, the BCVA at the final follow-up was compared between the eyes with and those without abrupt visual loss. RESULTS: The mean follow-up period was 42.4±18.9mo after diagnosis, and abrupt visual loss was noted in 22 eyes (16.1%) at a mean of 19.6±13.9mo. Abrupt visual loss was found to be associated with subretinal hemorrhage in 11 eyes (50.0%), development of or increase in the height of pigment epithelial detachment with fluid in 8 eyes (36.4%), and tears in the retinal pigment epithelium in 3 eyes (13.6%). The logarithm of minimum angle of resolution (logMAR) mean BCVA at the final follow-up was 2.07±0.67 (Snellen equivalents: 20/2349) and 1.00±0.55 (20/200) in eyes with and without abrupt visual loss, respectively. BCVA was significantly worse in the eyes with abrupt visual loss (P<0.001). CONCLUSION: Abrupt visual loss is noted in 16.1% of patients with type 3 neovascularization and is associated with poor visual outcome. Additional studies are needed to determine how abrupt visual loss can be prevented.  相似文献   
108.
Grape seed is an important natural bioactive product with various health benefits. Interstitial cells of Cajal (ICCs) are pacemaker cells in the gastrointestinal (GI) tract. The present study investigated the effects of grape seed powder (GSP) on ICC properties and GI motility. GSP depolarized the pacemaker potentials of ICCs in a dose‑dependent manner. Y25130 or SB269970 slightly inhibited GSP‑induced effects. However, Y25130 and SB269970 together completely blocked GSP-induced effects. In the presence of inhibitors of protein kinase C, protein kinase A, or mitogen-activated protein kinase, GSP‑induced ICC depolarization was inhibited. GSP increased the intestinal transit rate in normal mice and in mice with acetic acid-induced GI motility disorder. In addition, the levels of motilin and substance P were elevated after GSP dosing. These results demonstrate that GSP can regulate GI motility, and therefore, it is a potential therapeutic agent for treating GI motility disorders.  相似文献   
109.
BackgroundThe aim of this study was to evaluate clinical outcomes of sodium tetradecyl sulphate (STS) sclerotherapy for conservative treatment of lateral malleolar bursitis of the ankle.MethodsWe reviewed data from 20 consecutive patients (20 ankles) who underwent STS sclerotherapy between August 2018 and June 2019. After aspiration of fluid from the lateral malleolar bursal sac, 2 mL (20 mg) STS was injected into the sac. Clinical outcomes and side effects and complications were evaluated at 2 weeks, 3 months, 1 year, and 2 years after sclerotherapy. Responses to treatment were assessed according to degree of fluctuation, shrinkage of the bursal sac, and soft-tissue swelling. The 36-item short form survey (SF-36) was completed for each patient before and after therapy.ResultsComplete response was observed in 17 patients (85%), and partial response was observed in 3 patients (15%) after STS sclerotherapy. SF-36 physical component scores improved from 62.2 (interquartile range, 5.2) before therapy to 70.0 (interquartile range, 7.9) at last follow-up (p < 0.05). One patient (5%) experienced transient hyperpigmentation at the injection site. No major complications occurred.ConclusionsSTS sclerotherapy was an effective and safe treatment for patients with lateral malleolar bursitis of the ankle.  相似文献   
110.
目的:测定市场上实际流通的商品胡桐泪药材中多糖的含量并对其单糖组成进行分析,以多糖为指标评价药材质量。方法:采用苯酚-硫酸法对总多糖进行含量测定;应用核磁共振氢谱(1H-NMR)分析单糖组成;运用高效凝胶渗透色谱(HPGPC)测定总多糖的分子量分布。结果:以葡萄糖计,4批新式胡桐泪总多糖含量平均值为(7.36±1.74)%,6批老式胡桐泪总多糖含量平均值为(1.53±0.99)%;新式与老式胡桐泪总多糖的单糖组成相似,主要由阿拉伯糖和半乳糖组成,还含有木糖、甘露糖、鼠李糖等,部分样品尚含有较高含量的葡萄糖;新旧类型样品总多糖在分子量分布上存在较大差异。结论:新式胡桐泪的总多糖含量平均值较老式高,以多糖含量为评价指标时,新式样品总体质量较老式更好;应用核磁共振氢谱可以快速、准确地鉴定单糖组成。  相似文献   
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