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71.
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   
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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   
75.
Laparoscopic Heller myotomy (LHM) has become the standard treatment option for achalasia. The incidence of esophageal perforation reported is about 5%–10%. Robotically assisted Heller myotomy (RAHM) is emerging as a safe alternative to LHM. Data comparing the two approaches are scant. The aim of this study was to compare RAHM with LHM in terms of efficacy and safety for treatment of achalasia. A total of 121 patients underwent surgical treatment of achalasia at three institutions. A retrospective review of prospectively collected perioperative data was performed. Patients were divided into two groups: group A (RAHM), 59 patients, and group B (LHM), 62 patients. All the operations were completed using minimally invasive techniques. There were 63 women and 58 men, with a mean age of 45 ±19 years (14–82 years). Fifty-one percent of patients in group A and 95% of patients in group B reported weight loss. Duration of symptoms was equal for both groups. Dysphagia was the main complaint in both groups (P = NS). There was no difference in preoperative endoscopic treatment in both groups (44% versus 27%, P = NS). Operative time was significantly shorter for LHM in the first half of the experience (141 ± 49 versus 122 ± 44 minutes, P < .05). However, in the last 30 cases there was no difference in operative time between the groups (P = NS). Intraoperative complications (esophageal perforation) were more frequent in group B (16% versus 0%). The incidence of postoperative heartburn did not differ by group. There were no deaths. At 18 and 22 months, 92% and 90% of patients had relief of their dysphagia. This study suggests that RAHM is safer than LHM, because it decreases the incidence of esophageal perforation to 0%, even in patients who had previous treatment. At short-term follow-up, relief of dysphagia was equally achieved in both groups. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). This study was supported in part by a grant provided by Intuitive Surgical, Inc. and Ethicon Endo-Surgery, Inc.  相似文献   
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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   
78.
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   
79.
M Lengyel  A Jánosi  A Arvay 《Orvosi hetilap》1989,130(15):765-772
To study the incidence and risk factors of prosthetic valve endocarditis (PVE) we followed 99.5% of 912 patients who had valve replacement from January 1, 1981 through December 31, 1985, for 1 to 6 (mean 3) years. PVE occurred in 27 patients (2.96% or 0.98% per patient-year). The incidence of PVE in the aortic position (3.9%) was significantly higher than in the mitral position (1.5%): p less than 0.25. PVE developed in 19 out of 329 patients with bioprostheses (5.8%) and in 8 out of 583 patients with mechanical valves (1.4%): p less than 0.005. Actuarially at 5 years follow-up 90.7% of the bioprosthetic group and 98.4% of the mechanical valve group was free of PVE (p less than 0.01). Bioprosthetic valve replacement in infective endocarditis further increased the risk of PVE compared to valve replacement by mechanical prostheses. In conclusion: in order of importance antecedent endocarditis, bioprostheses, male sex and aortic position are risk factors in the development of PVE. In patients requiring operation for infective endocarditis, mechanical valves are recommended. As the outcome of PVE is still very grave, authors stress the importance of prophylaxis, early diagnosis and timely operation.  相似文献   
80.
We investigated the effects of anti-psoriatic therapy with dithranol (1/20-1%) in salicylic acid (0.5%) in white petrolatum on lesional skin. FITC-labeled lectins and pemphigus vulgaris antibodies (PV) served as analytical means to study the glycocalyx. Antibodies of bullous pemphigoid (BP) were used as basal membrane markers. Nuclear antigens were recorded according to the binding of speckled, anti-nuclear antibodies (ANA) as well as antibodies to dsDNA. With some lectins, dithranol therapy resulted in pronounced fluorescence of the lower parts of the basal cells. ConA was fixed by the basal cell layer. To a lesser degree, ANA were fixed by nuclei of keratinocytes. PV antibodies were not fixed at all.  相似文献   
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