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991.

Background

There is some controversy about the relevance of lymphadenectomy in patients with early stage endometrial cancer. The aim of this study was to evaluate the contribution of sentinel lymph node (SLN) biopsy in staging patients with presumed low- and intermediate-risk endometrial cancer.

Methods

This retrospective multicenter study was conducted from July 2007 to December 2011 including 103 patients with presumed low- or intermediate-risk endometrial cancer who had undergone SLN biopsy. Concordance between preoperative staging and definitive histology as well as contribution of SLN biopsy and ultrastaging to upstage patients were assessed.

Results

SLNs were detected in 89 patients (86.4 %), 56 (62.9 %) of whom had presumed low-risk and 33 (37.1 %) intermediate-risk endometrial cancer. Of the 89 patients, 14 (15.7 %) had positive SLNs. Twelve (21.4 %) of the 56 patients with presumed low-risk disease were upstaged by definitive histology, among whom 3 (25 %) had pelvic positive SLNs. Seven (21.2 %) of the 33 patients with intermediate-risk disease were upstaged by definitive histology, 1 (14.3 %) of whom had positive SLNs. Ultrastaging detected metastases undiagnosed by conventional histology in 6 (42.8 %) of 14 of patients with positive SLNs.

Conclusions

SLN biopsy associated with ultrastaging is relevant to stage low- or intermediate-risk endometrial cancer and could help guide adjuvant therapies.  相似文献   
992.
Emile M. Scarpelli 《Lung》1984,162(1):61-71
Mechanical properties of the liquid-filled fetal lung are similar to those of the adult lung in so far as pulmonary tissue offers little resistance to volume change, but not to liquid flow, throughout its volume range. Contrary to what has been held, fetal lungs are not highly plastic. As fetal development progresses, tissue elastance probably falls as tissue-to-potential airspace density decreases. At the same time, liquid in future airspaces is enriched with phospholipid surfactants secreted by maturing type 2 saccular epithelial cells. When air-breathing begins at birth, dispersion of air into surfactant-rich liquid ofmature lungs results in formation of stable bubbles, the films of which achieve surface tension near-zero. Saccules are distended by the air-containing bubbles as well as by “free” air in direct communication with the airways. Stable bubbles establish immediate formation of functional residual capacity, continued gas exchange throughout the respiratory cycle, and saccular resistance to collapse as a result of the near-zero surface tension of and the structural stability provided by bubble films. This process produces the mature volume-pressure diagram, both in vivo and in vitro, which is characterized by relatively low opening pressure, high maximal volume, wide hysteresis and retention of large volumes at end-deflation or end-expiration. High expiratory pressures in vivo probably enhance production and distribution of bubbles. Surfactant-poorimmature lungs do not have the capacity to produce stable bubbles. As a consequence, initial aeration requires high opening pressure, achieves proportionately small maximal volume, and results in little hysteresis and gas retention during deflation. This is the underlying pathophysiologic derangement of neonatal respiratory distress syndrome.  相似文献   
993.
Background: We assessed the feasibility of a laparoscopic sentinel node (SN) procedure based on the combined use of radiocolloid and patent blue labeling in patients with endometrial cancer.Methods: Seventeen patients (median age, 69 years) with endometrial cancer of stage I (16 patients) or stage II (1 patient) underwent a laparoscopic SN procedure based on combined radiocolloid and patent blue injected pericervically. After the SN procedure, all patients underwent complete laparoscopic pelvic lymphadenectomy and either laparoscopically assisted vaginal hysterectomy (16 patients) or laparoscopic radical hysterectomy (1 patient).Results: SNs (mean number per patient, 2.6; range, 1–4) were identified in 16 (94.1%) of the 17 patients. Macrometastases were detected in three SNs from two patients by hematoxylin and eosin staining. In three other patients, immunohistochemical analysis identified six micrometastatic SNs and one SN containing isolated tumor cells. No false-negative SN results were observed.Conclusions: An SN procedure based on a combination of radiocolloid and patent blue is feasible in patients with early endometrial cancer. Combined use of laparoscopy and this SN procedure permits minimally invasive management of endometrial cancer.  相似文献   
994.
BACKGROUND: Two inbred Lewis rat substrains (LEW/Moe, LEW/Maa) were identified responding differently to induction of anti-Thy 1 glomerulonephritis (aThy 1-GN). LEW/Moe rats show an acute mesangioproliferative glomerulonephritis with rapid healing of glomerular lesions within four weeks, while LEW/Maa rats develop severe glomerular injury followed by chronic glomerular sclerosis and persistent albuminuria. We investigated whether the glomerular expression pattern of nitric oxide synthase (NOS) isoforms could explain these substrain-related differences. METHODS: Rats (N = 5 to 7 per group) were investigated in a time course experiment. Severity of aThy 1-GN was determined by albuminuria measurements, glomerular matrix score and microaneurysm formation. Glomerular gene expression of NOS isoforms was determined by semiquantitative RT-PCR. Inducible NOS (iNOS) activity was determined in cultured glomeruli and peritoneal macrophages. Neuronal NOS (nNOS) protein expression was detected by Western blotting and enzyme histochemistry. Plasma renin activity (PRA) was measured by RIA. RESULTS: Induction of iNOS expression and activity was found significantly increased and sustained in LEW/Maa vs. LEW/Moe rats associated with an increased number of infiltrating macrophages and with an increased capacity of iNOS-expression and iNOS-activation by isolated macrophages in LEW/Maa rats. Glomerular nNOS mRNA and nNOS protein expression were constitutively increased in LEW/Maa rats. Renal nNOS localization was restricted to the macula densa region in both substrains and associated with increased PRA in LEW/Maa rats. No difference in glomerular endothelial NOS-mRNA expression between the substrains was observed. CONCLUSIONS: Increased glomerular iNOS and nNOS expression were associated with chronic anti-Thy 1 glomerulonephritis in LEW/Maa rats and may contribute to glomerular damage by separate mechanisms.  相似文献   
995.
Isolated subtalar disorders often require subtalar arthrodesis. In this retrospective study of 28 in situ subtalar arthrodeses reviewed with a median follow-up of 56 months (range, 20–115), the authors attempted to detail the outcomes of in situ subtalar fusion, the consequences on adjacent joints and to determine clinical or radiological factors of failure. Clinical evaluation was realised with the AOFAS (American Orthopaedic Foot and Ankle Society) ankle hindfoot score. Radiographic evaluation included assessment of hindfoot alignment, subtalar fusion and arthritic evolution in the adjacent joints. The median functional score was 76.5/94 (range, 36–94). All 28 arthrodeses achieved union. Mild arthritic changes occurred in 43–65% in the different adjacent joints. These changes were not symptomatic. Varus malunion and clinical nonunion seem to be the most important causes of failure.  相似文献   
996.
Endothelial cell chimerism after renal transplantation in a rat model   总被引:8,自引:0,他引:8  
BACKGROUND: Endothelial chimerism, that is, the replacement of damaged donor endothelium by recipient precursors, has been proposed to reduce the allogeneic stimulus and graft rejection. However, both its mechanism and consequence are poorly understood. In this study, we set up a rat model of renal transplantation to investigate the phenomenon of endothelial chimerism and the relationship among the factors involved in its induction, such as preischemic injury, severity of graft rejections, and the role of cyclosporine A toxicity. METHODS: Female Lewis rats received renal transplants from male Brown Norway kidneys. Groups were divided according to ischemia or nonischemia of the donor kidney and cyclosporine treatment or nonimmunosuppression. To investigate the endothelial chimerism, an in situ hybridization by an X-chromosome-specific DNA probe was performed. The severity of allograft rejection was scored according to the Banff '97 classification. RESULTS: In grafts without preischemic injury or without cyclosporine A treatment, a low degree of endothelial chimerism was detected, although severe vascular rejection and tissue necrosis developed. More chimerism was found in recipients receiving an ischemic kidney followed by immunosuppressive treatment, although less severe rejection developed. In recipients receiving an ischemic kidney without cyclosporine A treatment, the highest degree of endothelial chimerism occurred. CONCLUSIONS: Endothelial chimerism demonstrated in rats after renal transplantation may be caused by endothelial damage induced by vascular rejection or ischemia. Ischemia had the strongest association with the induction of chimerism, which may function as a synergistic promoter. A low-dose cyclosporine A treatment was shown to inhibit endothelial replacement.  相似文献   
997.
OBJECTIVE: To prospectively investigate determinants of the accuracy of staging axillary lymph nodes in breast cancer using [F-18]fluorodeoxyglucose positron emission tomography (FDG PET). METHODS: Patients with primary operable breast cancer underwent FDG PET of the chest followed by sentinel node biopsy (SNB, n = 47) and/or complete axillary lymph node dissection (ALND, n = 23). PET scans were independently interpreted by three observers in a blinded fashion with respect to the FDG avidity of the primary tumor and the axillary status. The results were compared to histopathological analyses of the axillary lymph nodes. Clinicians were blinded to the PET results. RESULTS: Axillary lymph node specimens and FDG PET scans were evaluated in 70 patients (59% cT1). Overall, 32 (46%) had lymph node metastases as established by SNB (18/47) or ALND (14/23), 20 of which were confined to a single node. The overall sensitivity of FDG PET was 25%, with a specificity of 97%. PET results were false-negative in all 18 positive SNBs and true-positive in 8/14 in the ALND group. The performance of FDG PET depended on the axillary tumor load and the FDG avidity of the primary tumor. Intense uptake in the primary tumor was found in only 57% of the patients, and this was independent of the size. There was excellent interobserver agreement of visual assessment of FDG uptake in primary tumor and axillary lymph nodes. CONCLUSIONS: The sensitivity of FDG PET to detect occult axillary metastases in operable breast cancer was low, and it was a function of axillary tumor load and FDG avidity of the primary tumor. Even though the clinical relevance of occult disease detected by SNB needs to be confirmed, it is suggested that FDG PET in these patients should be focused on exploiting its nearly perfect specificity and the potential prognostic relevance of variable FDG uptake.  相似文献   
998.
999.
Objective To evaluate the contribution of the sentinel node (SN) procedure followed by pelvic and paraaortic lymphadenectomy to determine lymph node status in women with locally advanced cervical cancer. Patients and methods A total of 21 women with locally advanced cervical cancer underwent a first laparoscopic SN procedure and pelvic and paraaortic lymphadenectomy followed by concurrent chemoradiotherapy (CCR). Laparoscopic radical hysterectomy was performed after CCR when the pelvic and paraaortic nodes were not involved. Results SNs were detected by means of lymphoscintigraphy in 10 women (47.6%) and intra-operatively in 14 women (66.6%). Of the latter 14 patients, 9 (64%) had an involved SN and 1 of the remaining 5 had pelvic non-SN metastases. The SN false-negative rate was 10%. At final histology, 13 of the 21 women (62%) had lymph node metastases. The total number of recovered pelvic non-SNs was 262, and 10 nodes in 8 women were involved. The total number of paraaortic non-SNs was 255, and 2 nodes in 2 women were involved. Conclusion This study shows the poor correlation between pre-operative lymphoscintigraphy and surgical SN mapping in women with locally advanced cervical cancer. A high proportion of women had SN metastases, underlining the importance of multiple sectioning and immunohistochemical staining of SNs.  相似文献   
1000.
An aberrant right subclavian artery can be used in a variety of ways in complex aortic arch reconstructions. Four patients (3 with interrupted aortic arch and 1 with coarctation) in whom this technique was used are presented.  相似文献   
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