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Constituents of Fagaceae (Cupuliferae), XIX: Triterpene Saponins and Acylated Flavonoids from Quercus robur L. var. stenocarpa Beck. In addition to four known glycosides from leaves of Quercus robur L. var. stenocarpa Beck. a new triterpene saponin has been isolted and identified as 28-β-d-glucopyranosyl ester of the 2α,3β,19α-trihydroxy-olean-12-ene-24,28-dioic acid ( I ).  相似文献   
3.
Antibiotic Use in Crohn’s Disease   总被引:3,自引:0,他引:3  
On the assumption that bacteria in the gut may be a cause of symptoms and/or complications of Crohn's disease, various antibiotics are efficaciously employed in some affected patients. However, we do not know exactly why and how they are helpful. A possible explanation is that one or several bacterial species may have a primary role in the aetiology of Crohn's disease, but this is not supported by the data in our possession. Another hypothesis is that intestinal bacteria may cause flare-up of the disorder, either by inducing intestinal lesions or by an interaction with the immune system, but we know today that specific pathogens can cause flares only in a minority of cases. On the contrary, there is considerable evidence that the intestinal microflora and its products may amplify and perpetuate inflammation in Crohn's disease. Despite the fact that few controlled trials have been conducted, and have shown inconclusive results, antibiotics are widely employed for improving symptoms and for inducing remission of active phases. At present, a combination of metronidazole and ciprofloxacin, active against many enteric bacteria, has proved to be effective in the treatment of Crohn's disease complications. This therapy also seems to be effective in acute flares as an alternative to, or in combination with, corticosteroids.  相似文献   
4.
Spontaneous portosystemic shunts are commonly found in cirrhotic patients. Not yet established is their role after orthotopic liver transplantation (OLTx), especially when an increase in portal pressure develops, as during early acute rejection. In this study, 34 cirrhotic patients in a series of 70 OLTx are considered. Each patient had preoperative angiographic assessment, and, in 21 (62%), large spontaneous portosystemic shunts were evident. In 12 cases the shunts were not affected by the surgical procedure and were present during the postoperative period; in 9 the hepatectomy itself involved interruption of the shunts. The patient population was divided into two groups: patients with postoperative shunts (n=12) and those without (n=22). The two groups were similar in age, sex, Child's stage, transplantation variables, and number and grade of rejection episodes. However, mean transaminases (AST) values in the first 2 weeks were significantly higher levels in shunt versus nonshunt patients (421±335 vs 183±126; P<0.025), and this was even more evident when rejection occurred (626±375 vs 195±129; P<0.001). Furthermore, during an acute rejection reaction, three cases showed a true steal phenomenon through the large reopened shunts with ischemic damage to the grafts. The data indicate a possible detrimental effect of the spontaneous shunts on graft perfusion and suggest the prophylactic surgical interruption of the residual shunts during the transplantation.  相似文献   
5.
Clinical evidence of non-lymphatic distant metastasis has been reported in approximately 10% of cases of head and neck squamous cell carcinoma (HNSCC). The lungs are the commonest site of distant metastasis of HNSCC, followed by the bones, liver and skin. A 65-year-old male underwent supraglottic laryngectomy and left modified neck dissection for a carcinoma of the laryngeal surface of the epiglottis extending to both false cords. Eight months later the patient underwent right radical modified neck dissection for hypodermal metastatic disease involving the underlying (sternocleidomastoid) muscle. Thirty-two months later, surgical excision of a lesion in the right gluteus maximus muscle was performed. Histological study diagnosed a muscular metastasis with the same morphological aspect as the laryngeal carcinoma. The patient showed no evidence of cervical or distant recurrence at follow-up after 13 months. Although skeletal muscles represent approximately 50% of total body mass and receive a large proportion of total cardiac output, haematogenous metastases to skeletal muscle are extremely uncommon. Most skeletal muscle metastases are of pulmonary origin. Distant skeletal muscle metastasis from HNSCC is an extremely rare occurrence. Treatment options, depending upon the clinical setting, include observation, radiotherapy, chemotherapy and excision; these approaches rarely alter the patient outcome. The prognosis associated with skeletal muscle metastasis is thought to be poor, consistent with the fact that it generally occurs as a feature of systemic spread.  相似文献   
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Purpose  

To study the benefits of a single, early, intravesical instillation of mitomycin C(MMC) after transurethral bladder resection (TURB) in patients with low-risk non-muscle-invasive bladder cancer (NMIBC).  相似文献   
8.
We produced a non systematic review of ultrasound imaging of the pelvic floor in women with urinary incontinence (UI) and/or pelvic organ prolapse (POP). We have searched the PubMed and Embase databases for the following PICO question: women; imaging; urinary incontinence, pelvic organ prolapse, pelvic floor, pelvic floor muscle, pelvic floor muscle training; physical examination, no imaging; diagnosis, prognosis, outcome. The production of a systematic review was deemed impossible based on the type and quality of the published evidence. Clinical research focused on the pathophysiology of the UI and POP looking relation between anatomic abnormalities, childbirth, the risk of UI or POP, the outcome of conservative treatment and reconstructive surgery. Published papers fall into the remits of diagnostic studies but often fail to comply with the recommendations of the STARD initiative. Most published evidence remains the product of a single institution effort and confirmatory studies are rarely found. Imaging studies in patients with UI did not provide evidence of any clinical benefit in the management of patients. In patients with POP, interesting correlations have been identified such as between childbirth, dimension of levator hiatus, avulsion of levator ani and risk of prolapse, but the non clinical benefit of pelvic floor imaging could still not be identified. Research on pelvic floor imaging requires a coordinated, international, multicentre effort to improve internal and external validity of imaging techniques, confirm observations published by single institutions and provide health technology assessment of imaging in the management of UI or POP patients.  相似文献   
9.
OBJECTIVE: To assess the reliability of 18-fluorodeoxyglucose positron emission tomography (18-FDG PET) in distinguishing benign from malignant cystic lesions of the pancreas. SUMMARY BACKGROUND DATA: The preoperative differential diagnosis of cystic lesions of the pancreas remains difficult: the most important point is to identify malignant or premalignant cysts that require resection. 18-FDG PET is a new imaging procedure based on the increased glucose metabolism by tumor cells and has been proposed for the diagnosis and staging of pancreatic cancer. METHODS: During a 4-year period, 56 patients with a suspected cystic tumor of the pancreas underwent 18-FDG PET in addition to computed tomography scanning, serum CA 19-9 assay, and in some instances magnetic resonance imaging or endoscopic retrograde cholangiopancreatography. The 18-FDG PET was analyzed visually and semiquantitatively using the standard uptake value. The accuracy of 18-FDG PET and computed tomography was determined for preoperative diagnosis of a malignant cyst. RESULTS: Seventeen patients had malignant tumors. Sixteen patients (94%) showed 18-FDG uptake with a standard uptake value of 2.6 to 12.0. Twelve patients (70%) were correctly identified as having malignancy by computed tomography, CA 19-9 assay, or both. Thirty-nine patients had benign tumors: only one mucinous cystadenoma showed increased 18-FDG uptake (standard uptake value 2.6). Five patients with benign cysts showed computed tomography findings of malignancy. Sensitivity, specificity, and positive and negative predictive values for 18-FDG PET and computed tomography scanning in detecting malignant tumors were 94%, 97%, 94%, and 97% and 65%, 87%, 69%, and 85%, respectively. CONCLUSIONS: 18-FDG PET is more accurate than computed tomography in identifying malignant pancreatic cystic lesions and should be used, in combination with computed tomography and tumor markers assay, in the preoperative evaluation of patients with pancreatic cystic lesions. A positive result on 18-FDG PET strongly suggests malignancy and, therefore, a need for resection; a negative result shows a benign tumor that may be treated with limited resection or, in selected high-risk patients, with biopsy, follow-up, or both.  相似文献   
10.
Patients with pancreatic cancer often present with advanced disease; so, curative surgical resection is possible in a small number of patients. Palliation in these patients focuses particularly on relief of biliary obstruction. Palliative treatment modalities include both surgical and nonsurgical approaches. Biliary obstruction is initially treated with endoscopic biliary stenting, plastic or metallic stents. Both of these provide similar initial relief of biliary obstruction; however, plastic stents have a greater risk of occlusion and should be used in patients with short survival duration. Metallic stents have a greater initial cost, but provide an overall cost-saving in patients with expected survival more than 6 months. There is no evidence of benefit from routine stenting of jaundiced patients before resection. Surgical palliation for biliary obstruction should be primarily considered in patients who fail endoscopic or percutaneous biliary decompression or who develop gastroduodenal obstruction, It is also indicated for patients with good performance status and expected survival of over 6 months. Surgical decompression of biliary tree should be made with a choledochojejunostomy whenever feasible, associated to a gastroduodenal bypass.  相似文献   
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