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51.
Timothy M. Pawlik Ana Luiza Gleisner Luca Vigano David A. Kooby Todd W. Bauer Andrea Frilling Reid B. Adams Charles A. Staley Eduardo N. Trindade Richard D. Schulick Michael A. Choti Lorenzo Capussotti 《Journal of gastrointestinal surgery》2007,11(11):1478-1487
Re-resection for gallbladder carcinoma incidentally discovered after cholecystectomy is routinely advocated. However, the
incidence of finding additional disease at the time of re-resection remains poorly defined. Between 1984 and 2006, 115 patients
underwent re-resection at six major hepatobiliary centers for gallbladder carcinoma incidentally discovered during cholecystectomy.
Data on clinicopathologic factors, operative details, TNM tumor stage, and outcome were collected and analyzed. Data on the
incidence and location of residual/additional carcinoma discovered at the time of re-resection were also recorded. On pathologic
analysis, T stage was T1 7.8%, T2 67.0%, and T3 25.2%. The median time from cholecystectomy to re-resection was 52 days. At
the time of re-resection, hepatic surgery most often consisted of formal segmentectomy (64.9%). Patients underwent lymphadenectomy
(LND) (50.5%) or LND + common bile duct resection (43.3%). The median number of lymph nodes harvested was 3 and did not differ
between LND alone (n = 3) vs LND + common duct resection (n = 3) (P = 0.35). Pathology from the re-resection specimen noted residual/additional disease in 46.4% of patients. Of those patients
staged as T1, T2, or T3, 0, 10.4, and 36.4%, respectively, had residual disease within the liver (P = 0.01). T stage was also associated with the risk of metastasis to locoregional lymph nodes (lymph node metastasis: T1 12.5%;
T2 31.3%, T3 45.5%; P = 0.04). Cystic duct margin status predicted residual disease in the common bile duct (negative cystic duct, 4.3% vs positive
cystic duct, 42.1%) (P = 0.01). Aggressive re-resection for incidental gallbladder carcinoma is warranted as the majority of patients have residual
disease. Although common duct resection does not yield a greater lymph node count, it should be performed at the time of re-resection
for patients with positive cystic duct margins because over one-third will have residual disease in the common bile duct.
Presented at the 48th Annual Meeting of the Society for Surgery of the Alimentary Tract at Digestive Week 2007, Plenary Session,
Washington, DC, March 23, 2007. 相似文献
52.
Alfredo Avellaneda Fernández álvaro Pérez Martín Maravillas Izquierdo Martínez Mar Arruti Bustillo Francisco Javier Barbado Hernández Javier de la Cruz Labrado Rafael Díaz-Delgado Pe?as Eduardo Gutiérrez Rivas Cecilia Palacín Delgado José Ramón Ramón Giménez Javier Rivera Redondo 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2009,41(10):e1-e5
53.
Homid Fahandezh-Saddi Díaz Antonio Ríos-Luna Eduardo García-Rey Ma Jesus Rodea Butragueño Manuel Villanueva-Martinez Ma Elena Cantero-Yubero Miguel del Cerro-Gutiérrez 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2007,17(1):105-109
Treatment of chronic osteomyelitis of distal tibia is complex. It often requires the association of antibiotic therapy and a surgical procedure. This consists of exhaustive debridement of infected bone and soft tissue which must have adequate cutaneous coverage and vascular supply which enables creating a barrier to microorganisms and greater resistance to infection. Free or pedicled muscular flaps have been the techniques most often used for this type of lesions. Free flaps require a precise microsurgical technique and prolonged surgery. Pedicled muscular flaps do not provide sufficient coverage and vascularisation of the distal tibia for large size defects. The fasciocutaneous flap has been used for the treatment of coverage defects in the perimalleolar area and the heel. We report the utility of this flap as management of chronic osteomyelitis of the distal third of the tibia with complete healing of the infection and correct cutaneous coverage without complications. 相似文献
54.
Human papillomavirus and HIV coinfection and the risk of neoplasias of the lower genital tract: a review of recent developments 总被引:3,自引:0,他引:3
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Alex Ferenczy Franois Coutle Eduardo Franco Catherine Hankins 《Canadian Medical Association journal》2003,169(5):431-434
ONE OF THE RISK FACTORS FOR HUMAN PAPILLOMAVIRUS (HPV) INFECTION and subsequent lower genital tract neoplasias and cancers is impaired cell-mediated immunity. HIV-positive women with severe immunosuppression are 5 times more likely than HIV-negative women to have lower genital tract neoplasias. A corresponding increase in the risk of invasive vulvar and anal cancers, but not of cervical cancer, has also been observed among HIV-positive women. Treatment failure and recurrence of neoplasia occur much more frequently among HIV-positive than among HIV-negative women. In this review, we discuss recent advances in the understanding of the relation between HIV and HPV coinfection and the development of lower genital tract neoplasias and cancers in women. In addition, we present strategies for monitoring and treating noninvasive and invasive neoplasias of the lower genital tract in HIV-positive women. 相似文献
55.
Michael C. Cheung Eduardo A. Perez Manuel A. Molina Xiaoling Jin Juan C. Gutierrez Dido Franceschi Alan S. Livingstone Leonidas G. Koniaris 《Journal of gastrointestinal surgery》2008,12(4):731-738
Objective The objective of the study was to determine the outcomes for primary gastrointestinal melanomas (PGIM).
Material and methods The Surveillance, Epidemiology, and End Results database (1973–2004) was queried.
Results Overall, 659 cases of PGIM were identified. The annual incidence of PGIM was approximately 0.47 cases per million in 2000.
Overall median survival time was 17 months. Tumors were identified in the oral–nasopharynx (32.8%), anal canal (31.4%), rectum
(22.2%), esophagus (5.9%), stomach (2.7%), small bowel (2.3%), gallbladder (1.4%), and large bowel (0.9%). Univariate analysis
demonstrated age, tumor location, stage, surgery, and lymph node status were significant predictors of improved survival.
MST has not been reached for tumors located in the large bowel, while tumors located in the stomach demonstrated the shortest
median survival (5 months). Improvement in MST was observed for those patients undergoing surgical resection. The presence
of lymph node involvement conferred a poorer prognosis. Multivariate analysis of the cohort identified that location, advanced
tumor stage, failure to undertake surgical resection, positive lymph node status, and age were all independent predictors
of poorer outcome.
Conclusion PGIM occurs most often in the oral–nasopharynx and anal canal. Surgical extirpation is the only identifiable treatment modality
that significantly improves survival. 相似文献
56.
Sharon C. Reimold M.D. Sary F. Aranki M.D. Eduardo S. Caguioa M.D. Scott D. Solomon M.D. Vladimir Birjiniuk M.D. Lawrence H. Cohn M.D. Richard T. Lee M.D. 《Journal of cardiac surgery》1994,9(3):304-313
Objectives: The purpose of this study was to determine if a device placed externally around the aortic root decreases regurgitant flow in acute aortic regurgitation. Background: Aortic regurgitant flow is dependent on central aortic pressure and the aortic root and leaflet geometry. It may be possible to decrease aortic regurgitant severity by reducing aortic root size or dimension changes. Methods: Aortic regurgitation was created in eight calf heart specimens suspended in a continuous flow system. Retrograde and antegrade aortic flow and distending aortic pressure were measured at baseline and after placement of an external aortic device at the level of the aortic annulus. In two additional specimens, the incompetent aortic valve was visualized fiberoptically before and after placement of the external device. Acute aortic regurgitation was created surgically in four live calves by excising a portion of the aortic leaflets. Antegrade and retrograde flow, left ventricular pressure, and central aortic pressure were measured at baseline, after creation of aortic regurgitation, and after placement of the external device. Results: In the in vitro calf specimens, regurgitant flow decreased from 46.9 cc/sec to 15.1 cc/sec (66.0%± 21.8% decrease) after placement of the external device (p < 0.001). The regurgitant orifice area decreased from 0.13 ± 0.04 cm2 to 0.04 ± 0.02 cm2 after device placement (p < 0.001). Antegrade flow was reduced to a smaller extent (20.0%± 19.2% decrease) by the device (p < 0.05). Placement of the device around the aorta resulted in improved coaptation of the leaflets with a marked reduction in defect size by endoscopic visualization. Use of the external aortic device was associated with improvement in aortic regurgitant severity in three of four calves with surgically created aortic regurgitation. Concluslons: In these preliminary studies, acute experimental aortic regurgitant severity is decreased by the use of an external aortic device, probably due to reduction in aortic annular dimension changes and improved aortic leaflet apposition. Further studies are needed to determine the effectiveness of this device in chronic aortic regurgitation. (J Card Surg 1994;9:304–313) 相似文献
57.
Giovanni Manfredi Tuan Vu Eduardo Bonilla Eric A. Schon Salvatore DiMauro Enrica Arnaudo Lee Zhang Lewis P. Rowland Michio Hirano 《Annals of neurology》1997,42(2):180-188
We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient. 相似文献
58.
Eduardo M. Salinas Jorge Cebada Alberto Valdés Anoland Garateix Abel Aneiros Julio L. Alvarez 《Toxicon》1997,35(12):1699-1709
The effects were studied of a toxin (Bainh) isolated from the secretion of the Caribbean sea anemone Bunodosoma granulifera on electrical and mechanical activities of rat ventricular muscle. The effects on the ionic currents of single rat and dog ventricular cardiomyocytes were studied using the whole-cell recording patch-clamp technique. In the concentration range from 1 to 10 mg/ml, Bainh increased the force of contraction and induced an increase in action potential duration of ventricular multicellular preparations. In single cardiomyocytes, at concentrations up to 10 mg/ml Bainh showed no significant effects on the sodium current. However, at 0.5–1 mg/ml it increased the L-type Ca current (ICaL) by 25–50%. This increase in ICaL was not voltage dependent and was reversible after washout. The transient outward current was not significantly affected by Bainh (1–10 mg/ml). In this concentration range, Bainh markedly (≈75%) increased the inward-going rectifier current, IK1. This effect that was not voltage dependent and was fully reversible upon returning to control solution. It is suggested that these effects on ionic currents could explain the positive inotropic action of Bainh on cardiac multicellular preparations. 相似文献
59.
Patricio López-Jaramillo Director Marcelo Narváez Professor rés Calle Professor José Rivera Consultant Patricio Jácome Registrar César Ruano Professor Eduardo Nava Consultant 《BJOG : an international journal of obstetrics and gynaecology》1996,103(1):33-38
Objective To elucidate the role of the L-arginine: nitric oxide pathway in pregnancy and pre-eclampsia.
Participants Pregnant women (nulliparous, age < 25 years). Normotensive pregnancy ( n = 22 ) was defined when blood pressure remained at levels of < 120/80 mmHg and there was no proteinuria. Women with pre-eclampsia ( n = 22 ) had blood pressure measurements of > 140/90 mmHg and proteinuria of > 300 mg/l. Nonpregnant normotensive women ( n = 22 ) were studied as controls.
Study Design Blood samples were taken for measurements of ionised calcium, atrial natriuretic factor, cyclic guanosine 3'5'monophophate (GMP), arginine and asymmetric dimethylarginine. Urine samples were collected for determination of cyclic GMP excretion. Cyclic GMP concentrations were also determined in 12 women with severe pre-eclampsia before and after treatment with hydralazine.
Results L-arginine, asymmetric dimethylarginine and atrial natriuretic factor were not different in any group. Cyclic GMP concentrations in plasma [0.94 (SD 0.23) nM] as well as in urine [50.1 (SD15.7)μM] were increased significantly ( P < 0.05 ) in normal pregnancy compared to nonpregnant controls [plasma mean 0.46 (SD 0.12) nM and urine mean 18.4 (SD 10.3) μM], but not in the pre-eclampsia group [plasma mean 0.48 (SD 0.10) nM and urine mean 24.1 (SD 14.5) μM]. Concentrations of cyclic GMP in plasma and urine increased significantly ( P < 0.05 ) in women treated with hydralazine.
Conclusions The differences in cyclic GMP concentrations may reflect differences in nitric oxide production. Hydralazine increases cyclic GMP concentrations in severely pre-eclamptic women. This action could explain the antihypertensive effect of hydralazine. 相似文献
Participants Pregnant women (nulliparous, age < 25 years). Normotensive pregnancy ( n = 22 ) was defined when blood pressure remained at levels of < 120/80 mmHg and there was no proteinuria. Women with pre-eclampsia ( n = 22 ) had blood pressure measurements of > 140/90 mmHg and proteinuria of > 300 mg/l. Nonpregnant normotensive women ( n = 22 ) were studied as controls.
Study Design Blood samples were taken for measurements of ionised calcium, atrial natriuretic factor, cyclic guanosine 3'5'monophophate (GMP), arginine and asymmetric dimethylarginine. Urine samples were collected for determination of cyclic GMP excretion. Cyclic GMP concentrations were also determined in 12 women with severe pre-eclampsia before and after treatment with hydralazine.
Results L-arginine, asymmetric dimethylarginine and atrial natriuretic factor were not different in any group. Cyclic GMP concentrations in plasma [0.94 (SD 0.23) nM] as well as in urine [50.1 (SD15.7)μM] were increased significantly ( P < 0.05 ) in normal pregnancy compared to nonpregnant controls [plasma mean 0.46 (SD 0.12) nM and urine mean 18.4 (SD 10.3) μM], but not in the pre-eclampsia group [plasma mean 0.48 (SD 0.10) nM and urine mean 24.1 (SD 14.5) μM]. Concentrations of cyclic GMP in plasma and urine increased significantly ( P < 0.05 ) in women treated with hydralazine.
Conclusions The differences in cyclic GMP concentrations may reflect differences in nitric oxide production. Hydralazine increases cyclic GMP concentrations in severely pre-eclamptic women. This action could explain the antihypertensive effect of hydralazine. 相似文献
60.
Eneida F. Vencio Rita C. Alencar Eduardo Zancope 《Journal of oral pathology & medicine》2007,36(2):120-122
A 13-year-old boy had complained of an asymptomatic swelling in the anterior maxilla for approximately 4 years. The patient reported no local trauma. The intra-oral examination revealed an exophytic lesion in the incisive papilla between the maxillary central and lateral incisor teeth. The radiographies detected no significant findings. Histopathologically, the lesion showed a dense fibrous tissue above the overlying mucosa. Bone ossification lay beneath a partially hypertrophic cartilage showing occasionally pleomorphic chondrocytes. Because of its microscopic aspects, heterotopic ossification may be mistaken for chondrosarcoma or other conditions involving periosteum, such as parosteal osteosarcoma. A case of heterotopic ossification in the anterior maxilla is presented, and clinicopathologic similarities with other osteochondromatous lesions are discussed. 相似文献