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91.
Neurosurgical Review - The optimal management of cranioplasty infections remains a matter of debate. Most authors have suggested that the infected bone/implant removal is mandatory, combined with...  相似文献   
92.
BackgroundPostoperative hyperamylasemia is a frequent finding after pancreatoduodenectomy, but its incidence and clinical implications have not yet been analyzed systematically. The aim of this review is to reappraise the concept of postoperative hyperamylasemia with postoperative acute pancreatitis, including its definition, interpretation, and correlation.MethodsOnline databases were used to search all available relevant literature published through June 2019. The following search terms were used: “pancreaticoduodenectomy,” “amylase,” and “pancreatitis.” Surgical series reporting data on postoperative hyperamylasemia or postoperative acute pancreatitis were selected and screened.ResultsAmong 379 screened studies, 39 papers were included and comprised data from a total of 9,220 patients. Postoperative hyperamylasemia was rarely defined in most of these series, and serum amylase values were measured at different cutoff levels and reported on different postoperative days. The actual levels of serum amylase activity and the representative cutoff levels required to reach a diagnosis of postoperative acute pancreatitis were markedly greater on the first postoperative days and tended to decrease over time. Most studies analyzing postoperative hyperamylasemia focused on its correlation with postoperative pancreatic fistula and other postoperative morbidities. The incidence of postoperative acute pancreatitis varied markedly between studies, with its definition completely lacking in 40% of the analyzed papers. A soft pancreatic parenchyma, a small pancreatic duct, and pathology differing from cancer or chronic pancreatitis were all predisposing factors to the development of postoperative hyperamylasemia.ConclusionPostoperative hyperamylasemia has been proposed as the biochemical expression of pancreatic parenchymal injury related to localized ischemia and inflammation of the pancreatic stump. Such phenomena, analogous to those associated with acute pancreatitis, could perhaps be renamed as postoperative acute pancreatitis from a clinical standpoint. Patients with postoperative acute pancreatitis experienced an increased rate of all postoperative complications, particularly postoperative pancreatic fistula. Taken together, the discrepancies among previous studies of postoperative hyperamylasemia and postoperative acute pancreatitis outlined in the present review may provide a basis for stronger evidence necessary for the development of universally accepted definitions for postoperative hyperamylasemia and postoperative acute pancreatitis.  相似文献   
93.
Prospective trials demonstrate that sentinel node (SN) biopsy after neo-adjuvant chemotherapy (NACT) has a significant false-negative rate (FNR) when only 1 or 2 SNs are removed. It is unknown whether this increased FNR correlates with an elevated risk of recurrence. Tumor Registry data at an NCI-Designated Comprehensive Cancer Center were reviewed from 2004 to 2018 for patients having a negative SN biopsy after NACT. Among 190 patients with histologically negative nodes after NACT having 1 (n = 42), 2 (n = 46), and ≥3 (n = 102) SNs, axillary recurrences occurred in 7.14%, 0%, and 1.96% (p = 0.09), breast recurrences occurred in 2.38%, 6.52%, and 0.98% (p = 0.12), and distance recurrences occurred in 16.67%, 8.70%, and 7.84% (p = 0.27), respectively. Time to first recurrence did not differ by SN count (p = 0.41). After adjustment for age, race, clinical stage, and receptor status, there were no differences in the rates of axillary (p = 0.26), breast (p = 0.44), or distance recurrence (p = 0.24) by numbers of SNs harvested. Median follow-up was 46.8 months. Despite higher post-NACT FNRs reported in randomized trials for patients having <3 sentinel nodes, recurrence rates were not significantly different for 1 versus 2 versus ≥3 SNs. This suggests that patients having 1 or 2 post-NACT SNs identified may not necessitate axillary dissection.  相似文献   
94.
IntroductionBariatric surgery is effective therapy for weight loss and diabetes control. While patients with poorly controlled type 2 diabetes (T2D) experience significant benefit from bariatric surgery, the impact of hyperglycemia on perioperative risks is unclear.ObjectiveThis study aims to investigate effect of elevated glycated hemoglobin (HbA1C) on perioperative risks for patients undergoing sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB).Settings117,644 patients undergoing RYGB or SG between the years of 2017 and 2018 in the United Stated were analyzed. Data was obtained using the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database.MethodsThree commonly used cutoff levels of HbA1C were selected (6.5, 7.0, and 8.5). Complications were compared between groups of patients above and below each HbA1C level. Multivariable logistic regression models were used to account for confounders.ResultsWithout risk adjustment, HbA1C is indirectly associated with increased rates of surgical complications. However, after adjusting for underlying co-morbidities, HbA1C is not associated with overall complications, including 30 day readmissions, reoperations, reinterventions, or death at any HbA1C cutoff: 6.5 (odds ratio [OR] 1.041, P value = .219), 7.0 (OR 1.020, P value = .551), or 8.5 (OR 1.051, P value = .208).ConclusionThere is no direct relationship between HbA1C and early postoperative complications of SG and RYGB. Thus, optimizing preoperative HbA1C values alone, may not translate into decreased surgical complications of bariatric surgery. (Surg Obes Relat Dis 2020;17:271–275.) © 2020 American Society for Metabolic and Bariatric Surgery. All rights reserved.  相似文献   
95.
Weight regain following primary bariatric surgery occurs in a significant proportion of patients and is attributed to epidemiological, anatomical and metabolic factors. Surgical revision of these patients has significant risks and limited benefits. Endoscopic revisions that reduce gastric pouch size and diameter of the gastrojejunal anastomosis may offer an effective, safe, less invasive and even reproducible treatment. We herein discuss the indication, selection and feasibility of different endoscopic techniques that could be used in the management of weight regain following primary bariatric surgery. Future research could optimize a personalized approach not only in the endoscopic management but also in combination with other therapeutic modalities for weight regain after bariatric surgery.  相似文献   
96.
A hospital-based case-control study of renal cell cancer was conducted in northern Italy betwen 1986 and 1989, with 240 cases of renal cell cancer (150 males and 90 females), and 665 controls (445 males and 220 females) chosen on the basis of age, sex, and area of residence. No associations were found between renal cell cancer and: body mass index (BMI); number of cigarettes smoked; age at starting to smoke; years of smoking; consumption of wine, beer, spirits, coffee, decaffeinated coffee; tea; intake of animal protein, fruits, and vegetables; various resproductive factors; hormonal use; sexual habits; sexually transmitted diseases; or selected occupational exposures. The odds ratio (OR) was above unity in smokers (OR=1.34 for 15 cigarettes/day), but the trends in risk with dose or duration were not statistically significant. Significant positive associations were found between renal cell cancer and sources of fat intake, especially margarine (OR for highest vs lowest intake = 1.71), and oils (OR=1.89) whereas carrot intake showed a negative association (OR=0.62). Also, a history of nephrolithiasis and multiple episodes of cystitis showed weak positive associations (OR=2.00, 95 percent confidence interval (CI) 1.07–3.73; and OR=1.60, 95 percent CI 0.95–2.70, respectively).Address reprint requests to Dr Talamini. The work was conducted with the contribution of the Italian Association for Cancer Research, Milan, Italy and the CNR (Italian National Research Council) Applied Projects Oncology (Contract n. 85.02209.44).Drs Talamini, Barón, Barra, Bidoli, Serraino, and Franceschi are in the Epidemiology Unit, Aviano Cancer Center, Via Pedemontana Occ. 33081 Aviano (PN) Italy. At the time of this work, Dr Barón was a visiting biostatistician from the Department of Preventive Medicine and Biometrics, University of Colorado, Health Science Center, CO, funded by the National Cancer Institute (US) and the Italian National Research Council. Dr Franceschi is also chief of the Hormones and Sexual Factors and Cancer Working Group of the European Organization for Cooperation in Cancer Prevention Studies, Bruxelles, Belgium. Drs La Vecchia and Negri are in the Mario Negri Institute for Pharmacological Research, Milan, Italy. Dr La Vecchia is also in the Institute of Social and preventive Medicine, University of Lausanne, Switzerland.  相似文献   
97.
HCV is ubiquitous. In 50% of all cases it causes chronic hepatitis that often evolves into liver cirrhosis and hepatocellular carcinoma. Recently HCV has been classified in 5 genotypes by Okamoto. The purpose of this study is to evaluate the prevalence of 5 genotypes in Campania, a region of Southern Italy, where the prevalence of anti-HCV antibodies ranges from 0.87 to 4%, and to evaluate the correlation between the HCV genotypes and the severity of histological damage. One hundred and thirty-five anti-HCV positive patients were enrolled and tested by PCR to identify HCV-RNA. One hundred and twenty-four patients resulted HCV-RNA positive. Genotyping was performed as described by Okamoto et al. with minor modifications of the specific primer to type III proposed by Silini et al. Eight patients were negative for all genotypes. Eight patients were positive for type I(1a), 61 for type II(1b), 39 for type III(2a), 11 for type IV(2b) and 1 for type V(3a). In 4 cases two different genotypes were present in the same sample [II(1b)-IV(2b), III(2a)-II(1b) twice, III(2a)-IV(2b)]. Histological evaluation of liver damage showed: CPH (22 cases), minimal CAH (56), severe CAH (31) and liver cirrhosis (15). There was no statistically significant correlation between the 5 genotypes and the severity of histological damage. Data on the prevalence of genotype II(1b) in Italy are similar to those reported for other European countries. The prevalence of genotypes in Southern Italy is similar to that reported in the population of Northern Italy.  相似文献   
98.
  1. Isolated basilar arteries from spontaneously hypertensive stroke-prone rats (SHRSP) are more sensitive to the contractile effect of 5-hydroxytryptamine (5-HT) than those from normotensive Wistar Kyoto rats (WKY). This has been attributed to a different proportion of 5-HT receptor subtypes mediating these responses. In the present study we have examined if differences in nitric oxide release could also contribute to this difference in sensitivity to 5-HT.
  2. At rest, the normalized internal diameter was significantly smaller in SHRSP (297.4±3.5 μm, n=88) than in WKY (375.1±4.0 μm, n=62, P<0.01) arteries. The contractile response to 100 mM KCl was higher in WKY (3.57±0.15 mN mm−1, n=22) than in SHRSP arteries (2.32±0.20 mN mm−1, n=28, P<0.01).
  3. When added on the plateau of contraction to 5-HT (1 μM), acetylcholine (ACh, 3 μM) evoked significant relaxation in all preparations from WKY (n=20), but only in 15 out of 26 preparations from SHRSP. The mean relaxations were 55.4±5.2% in WKY and 20.6±4.6% in SHRSP (as % of the contractile tone evoked by 5-HT; P<0.01).
  4. The NO synthase inhibitor Nω-nitro-L-arginine (L-NOARG, 0.1 mM) produced a similar increase in tone in both WKY and SHRSP. This tone was equal (in % of the contractile response to 100 mM KCl) to 70.8±4.4% in WKY (n=20) and 67.6±5.9% in SHRSP (n=26) and was reversed by L-arginine (1 mM) and by 1,4-dihydropyridine calcium channel blockers (10 nM nisoldipine, 10 nM lacidipine, 100 nM nifedipine). The L-NOARG-induced tone was absent when the arteries were bathed in phosphate-free Krebs (pH 7.4).
  5. EC50 values of 5-HT were about four fold smaller in SHRSP than in WKY arteries (P<0.01). The maximal response to 5-HT (Emax) was higher than 100 mM KCl-contraction in SHRSP but not in WKY arteries. Removal of endothelium produced a shift to the left of the 5-HT curve in WKY, but not in SHRSP arteries.
  6. When evoked in phosphate-free Krebs, the contractile responses to 5-HT showed tachyphylaxis, but the responses were reproducible by adding the agonist at 30 min intervals. In such conditions, EC50 values of 5-HT were about two fold smaller in SHRSP than in WKY arteries (P<0.01). In phosphate-free Krebs, the blockade of NO synthase did not change the contractile response to 100 mM KCl; it reduced EC50 and increased Emax of 5-HT in WKY, but not in SHRSP.
  7. These results confirm that the sensitivity to 5-HT is higher in basilar artery isolated from SHRSP than in those from WKY. They show that endothelium-dependent vasorelaxation to ACh is impaired in SHRSP. The finding that removal of endothelium or blockade of NO synthase augmented the contractile response to 5-HT in WKY, but not in SHRSP basilar arteries indicates that the difference in responsiveness to 5-HT observed between WKY and SHRSP basilar arteries might be, at least in part, related to dissimilarities in NO release. Furthermore, the L-NOARG-induced contraction sensitive to calcium channel blockers indicates that, in basilar arteries, NO production might lower L-type calcium channel opening and thereby control the tone of the vessels.
  相似文献   
99.
In recent years, several reports have contributed to a growing suspicion that there is immunologic involvement in proliferative intraocular disorders such as proliferative vitreoretinopathy and proliferative diabetic retinopathy. Immune privilege, as in the brain, ovary and testis, also exists in the eye. Therefore, immune responses to unique molecules of the eye, e.g. retinal S-antigen (S-Ag), which the immune system never learns to regard as self, are possible. This study describes the presence of S-Ag, a major soluble photoreceptor protein involved in the visual transduction cascade, in pathological vitreous. We employed indirect immunoblotting, with human retina as substrate, and demonstrated the occurrence of antiretinal antibodies in the sera of a series of patients with proliferative vitreoretinal disorders. Immunoblot analysis of physiological retina and lyophilized S-Ag, revealed this protein as a target molecule of the immunological involvement of the retina. Further immunochemical investigation, however, must clarify whether this autoimmune reaction is the cause, a consequence, or an aggravating factor of the disease. As we come to understand the cellular and molecular mechanism, a new generation of therapeutic strategies may be envisioned.Presented in part at the 18th Meeting of the Club Jules Gonin, Vienna, 1992  相似文献   
100.
(Received for publication on Apr. 28, 1997; accepted on May 15, 1998)  相似文献   
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