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991.
芳香化酶与乳腺癌的相关研究   总被引:1,自引:1,他引:0  
雌激素在乳腺癌的发生发展中起着重要作用。绝经后妇女的雌激素主要由肾上腺分泌的雄激素前体转化而来,芳香化酶是这一转变过程的关键酶、限速酶。因此,深入研究芳香化酶和乳腺癌的关系具有重要的临床意义。现就芳香化酶在乳腺癌组织中的表达、调控及芳香化酶抑制剂在乳腺癌内分泌治疗中的临床进展作一综述。  相似文献   
992.
Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents at the same time as the initial laparoscopy. Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome measure was complications rates. Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was 3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction, and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified: one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications. Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct.  相似文献   
993.
Concepts in “fast-track” surgery, which provide optimal perioperative care, have been proven to significantly reduce complication rates and decrease hospital stay. This study explores whether fast-track concepts can also be safely applied and improve the outcomes of major pancreatic resections. Perioperative data from 255 consecutive patients, who underwent pancreatic resection by means of fast-track surgery in a high-volume medical center, were analyzed using univariate and multivariate models. Of the 255 patients, 180 received a pancreatic head resection and 51 received distal, 15 received total, and 9 received segmental pancreatectomies. The patients were discharged on median day 10 with a 30-day readmission rate of 3.5%. The in-hospital mortality was 2%, whereas medical and surgical morbidities were 17 and 25%, respectively. Fast-track parameters, such as first stools, normal food, complete mobilization, and return to normal ward, correlated significantly with early discharge (p < 0.05). Patients’ age, operation time, and early extubation proved to be independent factors of early discharge, shown through multivariate analysis (odds ratio: 4.0, 2.0, and 2.8, respectively; p < 0.05). Low readmission, mortality, and morbidity rates demonstrate that fast-track surgery is in fact feasible and safe and promotes earlier discharge without compromising patient outcomes.  相似文献   
994.
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer.  相似文献   
995.
胃癌术后胆囊结石形成的研究进展   总被引:1,自引:0,他引:1  
胃癌是消化道的常见肿瘤,手术切除仍是其主要治疗手段。胃癌术后除了常见的并发症外,患者胆囊结石的发病率明显升高,部分需要二次手术,其结石原因涉及神经、体液等多方面因素,本文就胃癌手术对胆囊结石形成的研究进展作一综述。  相似文献   
996.
This paper reviews the literature on colorectal cancer from a sex and gender-based perspective. Colorectal cancer is a major cause of death in the developed world, with rates increasing in developing countries. Although described by some writers as an ‘equal opportunity’ disease, it presents more risk to men than women. Both biological, or sex-linked factors, and gender-linked factors play a part in the aetiology of the disease, while gender differences in the use of screening and treatment also help shape the mortality gap between women and men for this condition. Without an appreciation of the part played by sex and gender in the risk of colorectal cancer, and without a gender-sensitive approach to screening in particular, it is possible that the mortality gap between men and women for this condition will widen in the future.  相似文献   
997.
BACKGROUND: Ten percent of gastric cancer (GC) cases are familial, with one third resulting from a mutation in the tumor suppressor gene CDH1. Loss of this important structure can result in hereditary diffuse gastric cancer (HDGC), which carries a high mortality if early diagnosis is not made. Despite its clear genetic origin, optimal management of HDGC family members is controversial, as the utility and efficacy of current cancer screening programs for mutation carriers are unproven. METHODS: A 53-year-old Caucasian woman was initially seen for genetic screening because multiple family members had mutations of the CDH1 gene. Her pedigree analysis demonstrated 4 generations of gastric cancer, and 2 of the generations carried the CDH1 germline mutation, consistent with HDGC. At endoscopy, the patient's gastric mucosa was normal and random biopsies were also normal. The patient underwent a laparoscopic total gastrectomy. RESULTS: The gross examination of her stomach appeared normal. On histologic examination, however, the stomach was found to have diffuse (signet ring cell) adenocarcinoma in-situ with 11 microscopic foci of invasive adenocarcinoma limited to the lamina propria. CONCLUSION: Our case is the first reported prophylactic total gastrectomy utilizing a laparoscopic approach, and it highlights the importance of taking a thorough family history and obtaining a pedigree analysis. Endoscopic screening in HDGC cannot rule out diffuse GC, because the stomach and biopsies can be normal despite the presence of adenocarcinoma. Therefore, our case supports the recommendation for prophylactic gastrectomy in HDGC.  相似文献   
998.
The etiology of epidermolysis bullosa acquisita (EBA) is unknown. EBA may be associated with other autoim‐mune systemic diseases; it also has been described in connection with different malignant tumors, showing complete remission after successful treatment of the tumor.In such cases, EBA may be regarded as a paraneo‐plastic dermatosis. We detected a highly differentiated neuroendocrine pancreatic cancer in a 78‐year‐old woman with EBA. Even thought her tumor was completely removed and the patient has been disease‐free for over seven years, a complete regression of her autoimmune bullous dermatosis could not be induced. By using intravenous immunoglobulins in combination with mycophenolate mofetil, further blister formation could be ameliorated.  相似文献   
999.
微生态肠内营养在结直肠癌患者围手术期的应用   总被引:2,自引:2,他引:0  
目的:探讨微生态肠内营养在结直肠癌患者围手术期应用中的疗效。方法:将90例结直肠癌患者随机分为3组:常规治疗组(RT)、肠内营养组(EN)及添加微生态制剂肠内营养组(EMN)。观察患者术中肠道清洁度以及术后排气时间、吻合口漏、感染情况以及菌群失调情况,并监测手术前后内毒素、CRP、TNF水平变化及淋巴细胞计数改变。结果:术后排气时间EN组及MEN组均早于RT组(P<0.05),而EMN组早于EN组(P<0.05);第1次排便后细菌油镜计数结果示EN组及MEN组均明显低于RT组(P<0.05),而EMN组低于EN组(P<0.05)。术后外周血内毒素及CRP水平EN组及MEN组均低于RT组(P<0.05),而EMN组低于EN组(P<0.05);外周血淋巴细胞计数EMN组较术前有所增加(P<0.05),其他两组无明显变化;TNF水平各组均高于术前水平(P<0.05)。肠腔清洁度、吻合口漏、切口感染率及腹腔感染率差异均无统计学意义(P>0.05)。结论:添加微生态制剂肠内营养能有效防治患者肠道菌群失调,增强机体免疫力,促进肠道功能恢复。  相似文献   
1000.
Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer.  相似文献   
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