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71.
Rodrigo O Perez Angelita Habr-Gama Igor Proscurshim Fábio G Campos Desiderio Kiss Joaquim Gama-Rodrigues Ivan Cecconello 《Journal of gastrointestinal surgery》2007,11(11):1431-8; discussion 1438-40
BACKGROUND: The role of local excision for pT2 distal rectal cancer has been challenged because of the observation of high rates of lymph node metastases and local failure. However, neoadjuvant chemoradiation therapy (CRT) has led to increased local disease control and significant tumor downstaging, possibly decreasing rates of lymph node metastases. In this setting, a possible role for local excision of ypT2 has been suggested. METHODS: A total of 401 patients with distal rectal cancer underwent neoadjuvant CRT. Tumor response assessment was performed after at least 8 weeks from CRT completion. One hundred and twelve patients with complete clinical response were not immediately operated on and were excluded from the study, and 289 patients with incomplete clinical response were managed by radical surgery. Patients with final pathological stage ypT2 were analyzed to determine the risk of unfavorable pathological features that could represent unacceptable risk for local failure after local excision. RESULTS: Eighty-eight (30%) patients had ypT2 rectal cancer. Final ypT status was not associated with pretreatment radiological staging (p = 0.62). ypT status was significantly associated with the risk of lymph node metastases, risk of perineural and vascular invasion, and recurrence (p = 0.001). Lymph node metastases were present in 19% of patients with ypT2 rectal cancer. The risk of lymph node metastases in ypT2 was associated with the presence of perineural invasion (47% vs 4%; p = <0.001), vascular invasion (59% vs 6%; p < 0.001), and decreased mean interval CRT surgery (12 vs 18 weeks; p < 0.001), but not with mean tumor size (3.2 vs 3.1 cm; p = 0.8). Disease-free and overall survival rates were significantly better for patients with ypT2N0 (p = 0.02 and 0.006, respectively). Fifty-five (63%) patients with ypT2 had at least one unfavorable pathological feature for local excision (lymph node metastases, vascular or perineural invasion, mucinous type or tumor size >3 cm). CONCLUSION: Lymph node metastases were present in 19% of patients with ypT2 and were significantly associated with poor overall and disease-free survival rates. The risk of lymph node metastases could not be predicted by radiological staging or tumor size. Radical surgery should be considered the standard treatment option for ypT2 rectal cancer after CRT. 相似文献
72.
73.
José Abal Arca Isaura Parente Lamelas Raquel Almazán Ortega José Blanco Pérez María Elena Toubes Navarro Pedro Marcos Velázquez 《Archivos de bronconeumologia》2009,45(10):502-507
Background and objectiveTo analyse frequency, characteristics and patient survival with lung cancer (LC) and Common Obstructive Pulmonary Disease (COPD), comparing them with patients that do not have COPD.Material and methodsA retrospective study, of patients diagnosed by means of cytohistology. Survival was estimated by the Kaplan-Meier method. Statistical analysis was carried out using SPSS 15.0.ResultsA total of 996 patients were diagnosed, 39.8% with COPD. Mean age70±9.19 years. GOLD stages: I 18.2%, II 53.6%, III 24%, IV 4.2%. The histological types: squamous cell carcinoma 48.2%, adenocarcinoma 22%, and small cell carcinoma 22.5%. Survival was longer in the COPD group.ConclusionsLC and COPD are combined in 39.8%. Squamous cell type is more frequent and survival was longer in the COPD group. 相似文献
74.
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76.
David Jiménez Castro Gema Díaz David Martí Carlos Escobar Javier Ortega Sergio García-Rull Joaquin Picher Antonio Sueiro 《Blood coagulation & fibrinolysis》2007,18(2):173-177
This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization. 相似文献
77.
Plasma levels and vascular effects of vasopressin in patients undergoing coronary artery bypass grafting. 总被引:1,自引:0,他引:1
Susana Novella Ana Cristina Martínez Rosa María Pagán Medardo Hernández Albino García-Sacristán Angel González-Pinto José María González-Santos Sara Benedito 《European journal of cardio-thoracic surgery》2007,32(1):69-76
OBJECTIVE: Recent studies have suggested that endogenous vasopressin (AVP) acts as a spasmogen during coronary artery bypass grafting (CABG). Given that AVP could induce vasospasm in the grafted vessel, we assessed the release of this peptide during and after CABG, and explored ways of counteracting its contractile effect on the internal mammary artery (IMA). METHODS: Plasma levels of AVP were determined by radioimmunoassay in 16 patients before, during and after CABG. Using isometric force recording techniques, we also investigated the mechanisms involved in the contractile effect of AVP in ring preparations of IMA specimens taken from 95 patients. RESULTS: Plasma AVP levels peaked after the start of cardiopulmonary bypass (CPB) and correlated well with serum osmolality (Pearson's r=0.9490; P<0.0001; n=16). An inverse correlation was observed between plasma AVP levels recorded at this stage and the maximal contraction induced in vitro by AVP in vascular rings from the same patients (Pearson's r=-0.6968; P<0.01; n=16). No change in the AVP response was produced by endothelium removal, exposure to the NO precursor (3 x 10(-4)M L-arginine), inhibition of nitric oxide (NO) synthase (3 x 10(-5) M L-NAME) or soluble guanylate cyclase (3 x 10(-6) M 1H-[1,2,4]oxadiazol [4,3,-alpha]quinoxalin-1-one (ODQ)), removal of the superoxide anion (100 U/ml superoxide dismutase (SOD) plus 1200 U/ml catalase) or hydroxyl radical (10(-4) M deferoxamine), or specific alpha1 - (10(-6) M prazosin) or endothelin (10(-5) M bosentan) receptor antagonism. In contrast, adenylate cyclase activation (3 x 10(-8) M forskolin) reduced the contractile response to AVP, while prostanoid synthesis (3 x 10(-6) M indomethacin) inhibition and blockade of Ca2+ -activated potassium channels (KCa) (10(-3) M tetraethylammonium (TEA)) enhanced AVP contraction. Age, gender and smoking also modified the AVP response. CONCLUSION: Our findings suggest a role for AVP as a modulator of vascular tone in human IMA. The effect of AVP is dependent on prostanoids and Ca2+ -activated K+ channels, so its dysfunction in pathophysiological cardiovascular processes could mean that AVP, among other factors, produces vasospasm in IMA grafts. 相似文献
78.
79.
M. Naranjo-Gómez M.A. Fernández M. Bofill R. Singh C.V. Navarrete R. Pujol-Borrell F.E. Borràs 《American journal of transplantation》2005,5(12):2838-2848
The role played by dendritic cell (DC) subsets in the immune response to alloantigens is not well defined. In vitro experiments have extensively shown that freshly isolated myeloid (M)DCs induce a strong T lymphocyte proliferation whereas plasmacytoid (P)DCs do not, unless activated by CD40 ligation. The aim of these studies was to explore whether the interplay among PDCs, MDCs and T cells modulates alloresponse. Freshly isolated MDCs and PDCs were merged in different proportions and used as antigen presenting cells (APCs) in mixed lymphocyte cultures (MLC). As described, isolated PDCs only induced a mild alloresponse, while MDCs were potent inducers of alloproliferation. Unexpectedly, when PDCs were merged with even low numbers of MDCs (down to 100 cells) and used as APCs, a potent Th1 cell proliferation was detected. Survival and maturation of PDCs was increased in these MLC conditions, which could partially explain the magnitude of the T-cell response. Interestingly, the proportion of IFNgamma-producing cells generated in such cultures was higher compared to MDC-stimulated cultures. These data suggest that the interaction between both DC subsets is determinant to generate a potent Th1 response, at least in an allogeneic situation, and may be relevant to the outcome of allogeneic stem cell transplantation. 相似文献
80.
J. M. Bellón N. García-Honduvilla N. Serrano M. Rodríguez G. Pascual J. Buján 《Hernia》2005,9(4):338-343
The component of a composite prosthesis, which makes contact with the visceral peritoneum, can be reabsorbable or non-reabsorbable,
and laminar or reticular. This study was designed to determine whether the composition of this second, barrier component could
improve its behavior at this interface. Abdominal wall defects in rabbits were repaired using a polypropylene prosthesis (PP),
or the composites Sepramesh (PP+h) or Vicryl (PP+v). Fourteen days after surgery, the implants were evaluated by light and
scanning electron microscopy, and immunohistochemistry. Prosthetic areas occupied by adhesions (PP: 71.08±5.09, PP+h: 18.55±4.96,
P+v: 69.69±16.81%), neoperitoneal thickness (PP: 256.17±21.68, PP+h: 83.11±19.63, PP+v:213.72±35.90 μm) and macrophage counts
(PP: 8.73±1.16, PP+h: 27.33±4.13, PP+v: 31.24±3.08%) showed significant differences (P<0.05). The tested biomaterials induced an optimal recipient tissue infiltration. Least adhesion formation was observed on
the PP+h implants. This suggests that the second component, although reabsorbable, should be smooth in structure. 相似文献