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991.
Vascular prosthetic graft infection is a major complication of vascular surgery that starts with adhesion of the microorganism to the graft. Because slime-forming microorganisms are the major causative agents in graft infection, the goals of investigators in this study were (1) to investigate the bacterial adherence of slime-forming and non-slime-forming coagulase-negative staphylococci (CNS), and (2) to determine the role of neuraminidase (NANase) in bacterial adherence to the biosynthetic ovine collagen graft. Human plasma was instilled and incubated at 37°C in preparation for fibrin deposition of grafts. After 48 hours, incubation grafts were drained and inoculated with slime-forming and non-slime-forming CNS in tryptic soy broth in the presence and in the absence of neuraminidase. After 24 hours of incubation at 36°C, grafts were vortexed and cultured for colony count. Bacterial counts were expressed as total colony-forming units per longitudinal centimeter of the graft. Slime-forming CNS had greater affinity to the collagen graft compared with non-slime-forming CNS (P < .05). Adherence of slime-forming CNS was impaired by NANase treatment (P < .001). NANase treatment of patients with non-slime-forming CNS did not change adherence to the graft (P > .05). Results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming CNS can be decreased through the administration of NANase. This may have implications for the development of neuraminidase-embedded vascular grafts designed to reduce the occurrence of biomaterial-related infection.  相似文献   
992.
Increased numbers of circulating endothelial cells (CECs) have previously been reported after various diseases associated with endothelial injury. The aim of this study was to evaluate the CECs in patients with Behçet’s disease and to demonstrate a possible association between CECs and disease activity. Sixty individuals (45 Behçet’s disease patients and 15 healthy controls) with normal renal function are included in the study. Peripheral blood samples are first incubated with antiCD146 antibody and subsequently conjugated to immunomagnetic beads to isolate CECs. Cells are stained with UEA-1 before counting. Behçet’s patients [7–135 cells/mL, mean 50 cells/mL, median 43 cells/mL (SD 35), < 0.001] have elevated numbers of CECs compared to controls [3–14 cells/mL, mean 9 cells/mL, median 8 cells/mL (SD 4)]. The number of CECs is higher in the active period of the disease compared to the inactive period. Further studies are needed to demonstrate the potential prognostic importance of CECs in Behçet’s vasculitis.  相似文献   
993.
This case report describes three hypertrophic cardiomyopathy patients with abnormal His-Purkinje conduction and complete atrioventricular block with attacks of syncope and cardiopulmonary arrest. Although arrhythmias are common in hypertrophic cardiomyopathy, complete atrioventricular block is very rare. Prolonged QRS duration and abnormal His-Purkinje system conduction may result in complete atrioventricular block.  相似文献   
994.
Metastasis of a malignant neoplasm to a benign tumor is an infrequent event. Adenomatous polyps of the colon have only been reported on three occasions acting as host tumors. We report the first case where a malignant melanoma metastasizing to a tubular adenoma in the colon was detected during colonoscopy. METHODS: An 85-yearold male with dementia and right hemiparesis presented to the hospital with change of bowel habits, signs and symptoms of anal incontinence, and a perianal ulcer. On physical examination, multiple subcutaneous nodules over his chest and abdominal wall were detected, and laboratory data revealed iron deficiency anemia. A colonoscopy was performed. RESULTS: During colonoscopy, a pedunculated, greenish-brown–colored polyp measuring 2 cm in greatest dimension located in the transverse colon was identified and snared. Pathology of this polyp was consistent with a malignant melanoma infiltrating into a tubular adenoma. Subsequently, one of the subcutaneous lesions was biopsied and this revealed malignant melanoma cells metastatic in soft tissue. The primary site of the malignant melanoma could not be identified. CONCLUSION: Polyp-cancer sequence is well documented in colorectal cancer. The vast majority of malignant lesions found in adenomatous polyps in the colon are the consequences of malignant transformation from benign neoplastic colonic adenomatous tissue. The possibility that colonic adenomatous polyps could harbor metastatic tumors should also be entertained. This could change the treatment and may require an appropriate workup.  相似文献   
995.
We report three cases of squamous cell carcinoma of the thyroid, which is an unusual malignant tumor that needs to be distinguished from other thyroid pathologies due to its aggressive behaviour. Three men, with an average of 63 years old, presented with progressive enlargement in the neck, hoarse voice or weight loss. Physical and radiological examinations revealed clues where malignancy was suspected and surgical resections were performed. Histopathological examination of the specimens was diagnosed as squamous cell carcinoma. Proper workup excluded the possibility of any primary site of SCC other than the thyroid. All patients died within 5 months. Adjuvant therapy evaluation is still inconclusive. Complete surgical resection still remains the primary choice for cure. We believe that radical resection with clear surgical margins followed by adjuvant chemo-radiation therapy is a curative strategy for achieving any chance of long-term survival.  相似文献   
996.
Failure of embryologic development of a lobe of the thyroid gland is a rare anomaly. Usually, this condition is diagnosed when there are some other pathologic conditions in the gland and is often found when a patient presents with a thyroid nodule, which in reality is compensatory hypertrophy of the side that is present, therefore appearing as a nodule. A variety of pathological conditions occur in the remaining thyroid tissue in association with this rare anomaly such as adenoma, carcinoma, subacute thyroiditis, colloid nodule, Graves' disease, simple goiter, and Hashimoto thyroiditis. Association of Graves' disease with ophthalmopathy and thyroid hemiagenesis is quite rare and very few cases are reported in the literature. We report a 29-year-old female presented as Graves' disease and Graves' ophthalmopathy with left lobe hemiagenesis of the thyroid gland.  相似文献   
997.
AIM: To study the levels of adiponectin in nondiabetic patients with nonalcoholic fatty liver disease (NAFLD) in comparison with control group. METHODS: Thirty-five patients who had elevated serum aminotransferase levels with bright liver and 34 healthy volunteers without liver disease were evaluated. Age, gender and body mass index (BMI) were recorded. Fasting plasma glucose, insulin, adiponectin, proinsulin and lipid profile were measured. A standard oral glucose tolerance test (OGTT) with insulin response was performed and the index of insulin resistance was calculated according to the homeostasis model assessment (HOMA) method. RESULTS: According to the OGTT results, none of the participants had diabetes. Serum adiponectin levels were statistically significantly lower in patients with NAFLD than in control group (8.14±3.4μg/mL vs 12.4±9.4μg/mL, respectively, P<0.01). A statistically significant correlation was found between adiponectin and BMI (r: -0.33, P<0.01), HOMA (r: -0.26, P<0.05), proinsulin (r:-0.32, P<0.01), AST (r: -0.25, P<0.05), ALT (r: -0.26, P<0.05) or GGT (r: -0.22, P<0.05). In multiple regression analysis models, adiponectin levels were the only predictor of NAFLD in males, whereas in female group it was the BMI. CONCLUSION: Low adiponectin level might be a predictor of NAFLD especially in male nondiabetics.  相似文献   
998.

Purpose

The aim of this study was to evaluate the impact of various factors on 30-day postoperative morbidity in patients who underwent colorectal surgery (CRS) for colovesical fistula (CVF) in the elective and emergency settings.

Methods

Patients who underwent CRS for CVF between 2005 and 2013 were identified from the American College of Surgeons National Surgical Quality Improvement Program database by using current procedural terminology codes. Demographics, perioperative, and operative factors were assessed and compared between two groups classified according to the presence or absence of postoperative complications.

Results

Five hundred twelve patients met the inclusion criteria [mean age of 61.4 (±14.7) years, female 214 (42%)]. Etiology of fistula was diverticulitis [N = 438 (85.5%)], colon cancer [N = 39 (7.6%)], and Crohn’s disease [N = 35 (6.8%)]. One hundred fifty-two procedures (29.7%) were performed laparoscopically. In 186 patients (36%), no bladder intervention was performed. One hundred forty-nine patients (29.1%) had at least one postoperative complication. Patients who developed complication were older (P = <0.001), more often female (P = <0.001), hypertensive (P = 0.005), anemic (P = <0.001), preoperatively transfused (P = 0.02), and with class 2–3 wound classification (P = 0.01). Independent risk factors affecting morbidity were increased age [odds ratio (OR) 1.23 (1.03–1.47), P = 0.01], decreased hematocrit level [OR 3.04(1.83–5.06), P < 0.0001], and open approach [OR 2.56 (1.35–4.84), P = 0.003].

Conclusions

Morbidity for CVF remains high. Lower preoperative hematocrit level and increased age were associated with higher risk of complication. Laparoscopic surgery may be preferable when possible as morbidity is less with this approach.
  相似文献   
999.
Pulmonary endarterectomy is the treatment of choice in suitable patients who have chronic thromboembolic pulmonary hypertension. The most common surgical technique involves the use of deep hypothermic circulatory arrest. Herein, we describe a modified aortic clamping technique with selective antegrade cerebral perfusion, performed with moderate hypothermia but without circulatory arrest. This technique avoids the adverse effects of deep hypothermic circulatory arrest and also establishes a bloodless surgical field. We achieved good surgical results and acceptable long-term outcomes in 3 patients with use of this technique, which we recommend as a feasible alternative to the standard operative practice.  相似文献   
1000.
We analyzed the ratio of serum total testosterone (sTT) to prostate-specific antigen (PSA) as a predictor of prostate cancer risk. One-hundred-four consecutive men with a normal digital rectal examination and a serum PSA level of 2.5–10 ng/ml underwent transrectal ultrasonography-guided biopsy using a 10-core scheme. The sTT level was determined before the procedure using a chemiluminescent assay, and the ratio of sTT to PSA (sTT/PSA) was calculated after transforming sTT measurements from ng/dL to ng/mL. The overall cancer detection rate was 17.3%. The median sTT level was 332 ng/dl in men with cancer and 413 ng/dL in those without (p = 0.032). The median sTT/PSA ratio in these groups was 0.55 and 0.74, respectively (p = 0.035). The receiver operator characteristic (ROC) method was used to evaluate the properties of the sTT/PSA ratio, with testosterone and PSA as predictors of prostate cancer risk. The accuracy of the sTT/PSA ratio in prostate cancer diagnosis, represented by the area under the curve (AUC), was 0.739 (95% CI 0.640–0.823, p < 0.05). Optimizing the sensitivity and specificity of the sTT/PSA ratio using the ROC provided a cutoff point of 0.60, which corresponded to 82% sensitivity and 62% specificity. When the patients were divided into normal- and low-sTT level groups according to testosterone value (300 ng/dl), the probability of detecting prostate cancer was 3.3-fold higher in hypogonadal men as compared with eugonadal men. These results support the use of the sTT-to-PSA ratio for predicting the risk of prostate cancer and increasing the specificity of PSA measurement.  相似文献   
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