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991.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.  相似文献   
992.
Silicon (Si) deficiency in animals results in bone defects. Choline-stabilized orthosilicic acid (ch-OSA) was found to have a high bioavailability compared to other Si supplements. The effect of ch-OSA supplementation was investigated on bone loss in aged ovariectomized (OVX) rats. Female Wistar rats (n = 58, age 9 months) were randomized in three groups. One group was sham-operated (sham, n = 21), and bilateral OVX was performed in the other two groups. OVX rats were supplemented orally with ch-OSA over 30 weeks (OVX1, n = 20; 1 mg Si/kg body weight daily) or used as controls (OVX0, n = 17). The serum Si concentration and the 24-hour urinary Si excretion of supplemented OVX rats was significantly higher compared to sham and OVX controls. Supplementation with ch-OSA significantly but partially reversed the decrease in Ca excretion, which was observed after OVX. The increase in bone turnover in OVX rats tended to be reduced by ch-OSA supplementation. ch-OSA supplementation increased significantly the femoral bone mineral content (BMC) in the distal region and total femoral BMC in OVX rats, whereas lumbar BMC was marginally increased. Femoral BMD was significantly increased at two sites in the distal region in OVX rats supplemented with ch-OSA compared to OVX controls. Total lumbar bone mineral density was marginally increased by ch-OSA supplementation. In conclusion, ch-OSA supplementation partially prevents femoral bone loss in the aged OVX rat model.  相似文献   
993.
This article presents the actual classification of neuromuscular diseases based on present expansion of our knowledge and understanding due to genetic developments. It summarizes the genetic and clinical presentations of each disorder together with CT findings, which we studied in a large group of patients with neuromuscular diseases. The muscular dystrophies as the largest and most common group of hereditary muscle diseases will be highlighted by giving detailed information about the role of CT and MRI in the differential diagnosis. The radiological features of neuromuscular diseases are atrophy, hypertrophy, pseudohypertrophy and fatty infiltration of muscles on a selective basis. Although the patterns and distribution of involvement are characteristic in some of the diseases, the definition of the type of disease based on CT scan only is not always possible.  相似文献   
994.
BACKGROUND: The presence of a left bundle branch block (LBBB) pattern on the electrocardiogram may frequently lead to perfusion defects in the septum not necessarily due to ischemic heart disease, but probably due to abnormal septal wall motion. The introduction of gated single photon emission computed tomography (SPECT) allows the evaluation of myocardial perfusion and function in one study. Accordingly, we analysed perfusion and function and the relation between perfusion and regional function in the septal region in patients with a LBBB without evidence of a previously sustained myocardial infarction. METHODS: We selected 37 patients with a LBBB without a history of a previous myocardial infarction, which was confirmed by echocardiography and/or coronary angiography. All patients underwent technetium-99m tetrofosmin gated SPECT myocardial imaging. Twelve control patients with a low likelihood of coronary artery disease and a normal technetium-99m tetrofosmin gated SPECT myocardial perfusion scintigram were selected as a reference population. The left ventricle (LV) was divided into 18 segments, which were scored for perfusion and function (wall motion and wall thickening) on a 4-point scale. RESULTS: The average LV end-diastolic volume was higher and the average LV ejection fraction was lower in patients with LBBB as compared to controls (142+/-90 vs. 81+/-18 ml, and 48+/-19 vs 62+/-7%, p=0.03 and p=0.02, respectively). Not only in the septum, but also in the other segments, reduced myocardial perfusion and abnormal wall motion/wall thickening was observed in the patients with LBBB (p<0.0001 vs controls). Patients with LBBB showed no correlation between perfusion and function in the septum, and between perfusion in septum and global LV function (r=0.21, p=0.2; r=0.10, p=0.6, respectively). Conversely, a good correlation was found between perfusion and function, either regional or global, in the remote segments (both r=0.79, p<0.0001). CONCLUSIONS: We conclude that patients with LBBB without a previous myocardial infarction show cardiomyopathic changes with perfusion and wall motion abnormalities, involving the entire left ventricle. The severity of diminished septal perfusion is not directly associated with the severity of septal wall motion abnormalities or global LV function. However, in the myocardial segments remote from the septum, reduced perfusion is closely associated with functional abnormalities.  相似文献   
995.
Imaging of the semicircular canals specifically is part of the imaging process of the temporal bone in general. The semicircular canals are easily seen on CT images and 3DFT-CISS-weighted MR images, both performed with 1.0-mm-thick slices, or even thinner slices. In selected cases, the T1-weighted images give unique information on the semicircular canals. This article briefly reviews the variety of semicircular canal anomalies that are most frequently present and can be routinely seen on CT and MR examinations of the temporal bone. It also provides a list that can be used by the radiologist in clinical practice to decide which technique, CT or MR, should be used to detect specific anomalies at the level of the semicircular canals.  相似文献   
996.
997.
Bone formation and resorption are influenced by inflammatory processes. We examined the relationships among inflammatory markers and bone mineral content (BMC) and density (BMD) and determined the contribution of inflammatory markers to 1-yr changes in BMC and BMD in healthy postmenopausal women. This analysis included 242 women at baseline from our parent Soy Isoflavones for Reducing Bone Loss project who were randomly assigned to 1 of 3 treatment groups: placebo, 80 mg/d soy isoflavones, or 120 mg/d soy isoflavones. BMD and BMC from the lumbar spine (LS), total proximal femur (hip), and whole body were measured by dual energy X-ray absorptiometry and the 4% distal tibia by peripheral quantitative computed tomography. Serum inflammatory markers (C-reactive protein, interleukin [IL]-1β, IL-6, tumor necrosis factor-alpha [TNF-α], and white blood cell count [WBC]) were measured at baseline, 6, and 12 mo. Because of attrition or missing values, data analysis at 12 mo includes only 235 women. Significant associations among IL-6, TNF-α, and WBC were observed with percent change in LS, hip, and whole body BMC and BMD. Multiple regression analysis indicated that in combination inflammatory markers accounted for 1.1–6.1% of the variance to the observed 12-mo changes in BMC and BMD. Our results suggest that modifying inflammatory markers, even in healthy postmenopausal women, may possibly reduce bone loss.  相似文献   
998.
After kidney transplantation, thrombotic microangiopathy (TMA) can occur de novo or as recurrent disease. Risk factors for de novo posttransplant TMA include ischemia-reperfusion injury, immunosuppressive drugs, viral infections, acute humoral rejection, and complement gene abnormalities. Cytomegalovirus infection as a trigger for posttransplant TMA in kidney transplant recipients has only been reported in 7 cases, all of them between 4 weeks and 8 years after transplantation. We describe a new case of de novo TMA in association with cytomegalovirus infection 25 years after kidney transplantation.  相似文献   
999.
BACKGROUND: A local anaesthetic with fast onset and short reliable duration of anaesthesia may be preferable for out-patient lower limb surgery. Articaine is believed to act faster and to have a shorter duration of action than bupivacaine, but there are no conclusive data available. The purpose of this study was to compare articaine and bupivacaine for day-case lower limb surgery. METHODS: Eighty patients planned for day-case lower limb surgery enrolled in this study. Patients were randomized to receive hyperbaric articaine 80 mg or plain bupivacaine 15 mg intrathecally. Primary outcome variable was recovery time from motor block. Secondary outcomes were: onset of sensory and motor block, maximum spread of sensory block, time to micturition, discharge from the hospital, and complications. RESULTS: The groups were comparable for the medians and the range of the maximum blocks after 30 min. Median time to complete regression of motor block was 101 min (range 80-129) for articaine compared with 307 min (range 225-350) for bupivacaine (P<0.0005). First spontaneous micturition occurred after 257 min (210-293) in the articaine group and after 350 min (304-370) in the bupivacaine group (P<0.0005). In the articaine and bupivacaine groups, patients were discharged after 300 min (273-347) and 380 min (332-431), respectively (P<0.0005). There was no significant difference in the occurrence of complications between the groups. CONCLUSIONS: Spinal anaesthesia with 80 mg of hyperbaric articaine has a shorter duration than a spinal anaesthesia with 15 mg of plain bupivacaine in lower limb surgery of approximately 1 h duration.  相似文献   
1000.
BACKGROUND: The Roux-en-Y gastric bypass procedure (RYGBP) is in many countries the gold standard for obtaining long-lasting weight reduction and improvement of obesity-related comorbidities. However, performing this operation by standard laparoscopic techniques requires important surgical skills because of the anastomoses involved. The da Vinci surgical robot system with its enhanced degrees of freedom in motion and three-dimensional vision is designed to overcome the difficulties encountered in traditional laparoscopic surgery with suturing and delicate tissue handling. METHODS: For this study, 45 patients (9 men) with a mean body mass index (BMI) of 44.2 (range, 35.1-55.4) underwent RYGBP with the aid of the da Vinci robot system. They were compared with 45 consecutive patients with a mean BMI of 43.9 (range, 35.1-56.2) who underwent a laparoscopic RYGBP by the same surgeon during the same period. RESULTS: Overall, the total operating time was shorter for the laparoscopic cases (127 vs 212 min; p < 0.05). However, the last 10 robotic cases were performed in the same time span as the laparoscopic cases (136 vs 127 min). The total robotic setup time remained constant at about 30 min. There were no differences in postoperative complications between the two groups in terms of anastomotic leakage or stenosis. In the robotic group, more conversions to open surgery were noted. Early in the study, four patients (9%) had to undergo conversion to standard laparoscopic techniques due to inadequate setup of the robotic arms. Five patients (11%), however, had to undergo conversion to open surgery because of intestinal laceration during manipulation of the intestines with the robotic instruments. The costs were higher for robotic surgery than for standard laparoscopic RYGBP, mainly because of the extra equipment used, such as ultrasonic devices. CONCLUSION: The RYGBP procedure can be performed safely with the da Vinci robot after a learning curve of about 35 cases. At this writing, however, it is not clear whether the da Vinci system offers a real advantage over standard laparoscopic techniques.  相似文献   
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