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61.
BACKGROUND AND PURPOSE: Twenty years after the first report of laparoscopic appendectomy (LA), its role in the treatment of appendicitis is still under debate. We report herein a retrospective analysis of our cases of LA in the last 5 years, during which we adopted a policy of an almost uniform laparoscopic approach on a rather selected population composed mainly of women with acute or recurrent lower quadrant abdominal pain. PATIENTS AND METHODS: Laparoscopic appendectomy was performed on 33 male and 98 female patients. The mean age at operation was 25.7+/-11.4 years (range 11-59 years). Acute appendicitis with localized or diffuse peritonitis was present in 34 cases. In the remaining 97 patients, the operation was performed for acute or recurring symptoms of lower quadrant abdominal pain. RESULTS: There were no conversions to open surgery. The operating time was 45+/-17 minutes (range 30-110 minutes). The pathology examination of the removed appendices showed acute appendicitis in 34 cases and chronic inflammation in the remaining 97 patients. In one case, histology revealed a coexisting mucinous carcinoid that extended to the perivisceral fat, and a completion right hemicolectomy was performed. Complications were minor in most cases. Reoperation for deep abdominal abscess or hematoma was required in three cases. The mean hospital stay was 2.59+/-1.58 days (range 24 hours-11 days). CONCLUSION: In our hands, LA has proven to be safe and effective. The laparoscopic operation has significant advantages in terms of lower invasiveness and better diagnostic capability. It is especially useful in women of child-bearing age, in whom it may be considered the procedure of choice.  相似文献   
62.
BACKGROUND: Incisional hernias are one of the most frequent complications of open abdominal surgery. The incidence of relapses after a conventional repair procedure is higher in recurrent than in primary cases (30%-50% vs. 11%-20%). The laparoscopic approach can prevent the complications associated with the conventional approach when dealing with recurrent incisional hernias. The aim of this study was to evaluate the efficacy of laparoscopic treatment in such cases. MATERIALS AND METHODS: We prospectively analyzed data from 41 consecutive patients with recurrent incisional hernias, who submitted to a laparoscopic repair procedure with an expanded polytetrafluoroethylene Dual Mesh (Gore-Tex Dual Mesh Plus Biomaterial; W.L. Gore 8 Associates) from December 2001 to December 2004. All of the patients underwent clinical follow-up at 1, 6, and 12 months and then yearly. An ultrasound scan of the abdominal wall was performed at 6 and 12 months after the procedure. The parameters considered for the analysis were: mesh size, operating time, hospital stay, postoperative complications, and recurrences. RESULTS: The defects were usually localized along midline laparotomies. The mean mesh size was 400 cm2, the mean operating time was 68 minutes, and the mean length of hospital stay was 2.7 days. Complications were encountered in 17% of patients. The mean follow-up was 38 months (range, 18-54). Recurrence was reported in 1 case only (2.4%), which occurred within the first 6 months after the operation. CONCLUSIONS: The laparoscopic repair of recurrent incisional hernia seems to be an effective alternative to the conventional approach, as it can give lower recurrence and complication rates.  相似文献   
63.
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice.  相似文献   
64.
BACKGROUND: Propofol (2,6-diisopropylphenol) has been shown to attenuate neuronal injury in a number of experimental conditions, but studies in models of cerebral ischemia have yielded conflicting results. Moreover, the mechanisms involved in its neuroprotective effects are yet unclear. METHODS: The authors evaluated the neuroprotective effects of propofol in rat organotypic hippocampal slices exposed to oxygen-glucose deprivation, an in vitro model of cerebral ischemia. To investigate its possible mechanism of action, the authors then examined whether propofol could reduce Ca2+-induced rat brain mitochondrial swelling, an index of mitochondrial membrane permeability, as well as the mitochondrial swelling evoked by oxygen-glucose deprivation in CA1 pyramidal cells by transmission electron microscopy. Finally, they evaluated whether propofol could attenuate the infarct size and improve the neurobehavioral outcome in rats subjected to permanent middle cerebral artery occlusion in vivo. RESULTS: When present in the incubation medium during oxygen-glucose deprivation and the subsequent 24 h recovery period, propofol (10-100 microM) attenuated CA1 injury in hippocampal slices in vitro. Ca2+-induced brain mitochondrial swelling was prevented by 30-100 microM propofol, and so were the ultrastructural mitochondrial changes in CA1 pyramidal cells exposed to oxygen-glucose deprivation. Twenty-four hours after permanent middle cerebral artery occlusion, propofol (100 mg/kg, intraperitoneal) reduced the infarct size by approximately 30% when administered immediately after and up to 30 min after the occlusion. Finally, propofol administered within 30 min after middle cerebral artery occlusion was unable to affect the global neurobehavioral score but significantly preserved spontaneous activity in ischemic rats. CONCLUSIONS: These results show that propofol, at clinically relevant concentrations, is neuroprotective in models of cerebral ischemia in vitro and in vivo and that it may act by preventing the increase in neuronal mitochondrial swelling.  相似文献   
65.
ObjectivesAberrant or increased expression of cyclooxygenase-2 (COX-2) has been implicated in the pathogenesis of many diseases, including cancer. However, the exact mechanism by which COX-2 may influence tumorigenesis has yet to be described. To investigate the chemopreventive role of a COX-2 inhibitor, rofecoxib, in the development of urinary bladder cancer, we studied the effect of this drug in heterozygous and nullizygous fragile histidine triad (FHIT) gene-deficient mice in a chemically induced carcinogenesis model.Materials and methodsTwo-hundred eight mice consisting of 50 FHIT +/+, 63 FHIT +/– and 95 FHIT –/–, were divided into five treatment groups and followed up for 15 weeks. Mice were treated with freshly prepared solution of 0.1% or 0.01% N-butyl-N-(-4-hydroxybutyl)-nitrosamine (BBN) in their drinking water and rofecoxib was administered in mouse chow at 150 parts per million concentration. Mice were sacrificed, and accurate histological analysis of the bladder was performed.ResultsRofecoxib treatment significantly reduced the incidence of preneoplastic lesions/bladder tumors (P = 0.016). Comparing the incidence of neoplastic lesions in mice treated with rofecoxib and BBN (22/56, 39.3%) and mice treated only with BBN (32/57, 56.1%), a protective role of rofecoxib on the BBN tumor induction has been observed (P = 0.024). A similar result (P = 0.002) has been reached observing the incidence of mild and moderate dysplasia in mice treated with a lower concentration of BBN (8/16, 50.0% vs. 20/24, 83.3%).Moreover, as previously observed, a significant increase in neoplastic lesions in the FHIT +/– and FHIT –/– vs. FHIT +/+ mice after BBN treatment has been observed (P = 0.003).ConclusionsThese findings suggest that rofecoxib provides a therapeutic defense against bladder carcinogenesis in our model and confirmed that the FHIT knock-out mouse is a suitable system to study in vivo bladder carcinogenesis.  相似文献   
66.
Background Resection line involvement has been indicated as an important prognostic factor for gastric cancer. Its late detection renders the choice of treatment difficult for surgeons. Materials and Methods We describe the multicenter experience of a group of 11 patients with early gastric carcinoma (EGC) and positive resection confirmed at histological examination who did not undergo surgical retreatment for reasons of associated disease, surgical considerations on duodenal stump, or patient refusal. Results The gastric margin was involved in 4 patients, and 7 patients had duodenal resection line involvement. No surgical complications or postoperative deaths were observed. Five and 8-year survival was 100% and 86%, respectively. The only patient who relapsed did not have lymph node involvement and died from liver metastases, without local recurrence. Conclusions It is sometimes difficult to accurately define the resection line in gastric cancer surgery, especially in the early stages of disease, but because of the strongly negative prognostic value of an infiltrated margin, frozen sections are recommended if neoplastic invasion is suspected and a new resection is always recommended if possible. Nevertheless, the good prognosis of resected EGC patients with resection line involvement must be considered before submitting patients with associated diseases to radical surgical retreatment.  相似文献   
67.
OBJECTIVE: To compare the presence or absence of a radiopaque lamina of 60 human periapical lesions with the histological findings from a case study in dental practice. STUDY DESIGN: Paralleling radiographs were taken of 60 teeth with periapical radiolucencies. The periapical radiographs were scanned, and standardized images were evaluated on a computer screen for the presence or absence of a radiopaque lamina by 2 calibrated observers according to agreed criteria. The serially sectioned histological specimens were obtained from the extraction of 13 endodontically treated teeth and 27 nontreated teeth, as well as 20 post-treatment teeth with apical periodontitis removed during periapical surgical procedure; the specimens were classified according to agreed criteria. The findings of the 2 evaluations were compared. RESULTS: Out of 57 electronic images that could be interpreted, 10 lesions had a radiopaque lamina, but of these only 3 were histologically diagnosed as cysts, while 7 were granulomas or abscesses. Out of 47 lesions without a radiopaque lamina, 40 were histologically diagnosed as granulomas or abscesses, while 7 were cysts. CONCLUSIONS: The diagnosis of periapical lesions cannot be made on the basis of the presence or absence of a radiopaque lamina, but requires histological examination of serial sections.  相似文献   
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70.
PURPOSE: Chronic anal fissure may be treated by chemical or surgical sphincterotomy. The aim of this study was to test the efficacy of local application of nifedipine and lidocaine ointment in healing chronic anal fissure. METHODS: The study was performed according to a prospective, randomized, double-blind design. One hundred ten patients who gave informed consent were recruited. They received a clinical examination, a questionnaire to evaluate symptoms and pain, anorectal manometry, and anoscopy. Healing of anal fissure at Day 42 of therapy was defined as the primary efficacy variable of the study. Patients treated with nifedipine (n = 55) used topical 0.3 percent nifedipine and 1.5 percent lidocaine ointment every 12 hours for 6 weeks. The control group (n = 55) received topical 1.5 percent lidocaine and 1 percent hydrocortisone acetate ointment during therapy. Anal pressures were measured by recording resting and maximal voluntary contraction pressures at baseline and at Day 21. Long-term outcomes were determined after a median follow-up of 18 months. RESULTS: Healing of chronic anal fissure was achieved after 6 weeks of therapy in 94.5 percent of the nifedipine-treated patients (P < 0.001) as opposed to 16.4 percent of the controls. Mean anal resting pressure decreased from a mean value +/- standard deviation of 47.2 +/- 14.6 to 42 +/- 12.4 mmHg in the nifedipine group. This represents a mean reduction of 11 percent (P = 0.002). Changes of maximal voluntary contraction in nifedipine-treated patients were not significant. No changes in mean anal resting pressure and maximal voluntary contraction were observed in the control group. We did not observe any systemic side effect in patients treated with nifedipine. After the blinding was removed, recurrence of the fissure was observed in 3 of 52 patients in the nifedipine group within 1 year of treatment, and 2 of these patients healed with an additional course of topical nifedipine and lidocaine ointment. CONCLUSIONS: Our study clearly demonstrates that the therapeutic use of topical nifedipine and lidocaine ointment should be extended to the conservative treatment of chronic anal fissure.  相似文献   
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