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1.
To investigate the clinical significance of intraoperative cultures in elective abdominal aortic aneurysmectomy, we cultured the aneuryrymml wall and contents in 90 patients undergoing vascular graft surgery. Prosthetic graft infection was documented in 1 out of 62 patients with negative cultures and in none of 28 patients with positive cultures (x2 = 0.4, p > 0.1). Bacterial growth was seen in neither of 2 inflammatory aneurysms, 3 of 14 atherosclerotic aneurysms and 2 of 5 aneurysms without specific features. A retrospective analysis of patients' charts aimed at finding possible risk factors failed to identify any correlation between results of cultures and length of hospitalization before surgery, time interval between angiography and surgery, route of angiography procedure or minutes of surgery before sample collection. We conclude that positive cultures may not imply clinical infection at the time of surgery and that prolonged post-operative organism-specific antibiotic therapy does not appear necessary to prevent graft contamination in patients undergoing elective abdominal aortic aneurysmectomy.  相似文献   
2.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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Trospectomycin, a new aminocyclitol antibiotic, was uniformly active against 69 isolates of enterococci with high-level resistance to steptomycin (54 isolates), gentamicin (27 isolates), ampicillin (19 isolates), ciprofloxacin (17 isolates), vancomycin (3 isolates), or teicoplanin (3 isolates). In time-killing studies, trospectomycin alone demonstrated no bactericidal activity. No synergistic interaction was demonstrated when trospectomycin was combined with ampicillin, vacomycin or ciprofloxacin.  相似文献   
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Baiocchi G, Raspagliesi F, Grosso G, Fontanelli R, Cobellis L, di Re E, di Re F. Early ovarian cancer: Is there a role for systematic pelvis and para-aortic lymphadenectomy? Int J Gynecol Cancer 1998; 8 : 103–108.
In order to focus on the incidence and the clinical significance of lymphatic spread in patients with cancer apparently confined to the ovaries, we present our 20 year experience in a large series of patients with early ovarian cancer who had systematic pelvic and para-aortic lymphadenectomy. A retrospective study of 280 consecutive patients is presented. Systematic pelvic and para-aortic lymphadenectomy was performed in 205 cases (73.2%). Selective sampling and node biopsy were performed in 30 (10.7%) and 7 (2.5%), respectively. Node metastases were found in 32/242 patients (13.2%). The incidence of metastatic nodes was significantly higher in patients with serous adenocarcinomas and/or poorly-differentiated tumors. When few nodes were involved (1–3) lymphatic spread was most ipsilateral to the tumor. Even though the retrospective nature of the study has to be considered, univariate analysis revealed statistically significant differences in 5-year survival based on FIGO stage, histology, grade of differentiation, and node status. By contrast, using multivariate analysis, none of these risk factors was an independent variable for predicting long-term survival. However, node status closely approached the statistically significant level ( P = 0.06). Only prospective and randomized studies can clarify the role of lymphadenectomy in early ovarian cancer. However, while awaiting these results, this surgical procedure should be a part of a research protocol.  相似文献   
7.
Background: Nitrate is a widespread groundwater contaminant and a leading cause of drinking water quality violations in California. Associations between nitrate exposure and select adverse birth outcomes have been suggested, but few studies have examined gestational exposures to nitrate and risk of preterm birth (before 37 wk gestation).Objective: We investigated the association between elevated nitrate in drinking water and spontaneous preterm birth through a within-mother retrospective cohort study of births in California.Methods: We acquired over 6 million birth certificate records linked with Office of Statewide Health Planning and Development hospital discharge data for California births from 2000–2011. We used public water system monitoring records to estimate nitrate concentrations in drinking water for each woman’s residence during gestation. After exclusions, we constructed a sample of 1,443,318 consecutive sibling births in order to conduct a within-mother analysis. We used separate conditional logistic regression models to estimate the odds of preterm birth at 20–31 and 32–36 wk, respectively, among women whose nitrate exposure changed between consecutive pregnancies.Results: Spontaneous preterm birth at 20–31 wk was increased in association with tap water nitrate concentrations during pregnancy of 5 to <10mg/L [odds ratio (OR)=1.47; 95% confidence interval (CI): 1.29, 1.67] and 10mg/L (OR=2.52; 95% CI: 1.49, 4.26) compared with <5mg/L (as nitrogen). Corresponding estimates for spontaneous preterm birth at 32–36 wk were positive but close to the null for 5 to <10mg/L nitrate (OR=1.08; 95% CI: 1.02, 1.15) and for 10mg/L nitrate (OR=1.05; 95% CI: 0.85, 1.31) vs. <5mg/L nitrate. Our findings were similar in several secondary and sensitivity analyses, including in a conventional individual-level design.Discussion: The results suggest that nitrate in drinking water is associated with increased odds of spontaneous preterm birth. Notably, we estimated modestly increased odds associated with tap water nitrate concentrations of 5 to <10mg/L (below the federal drinking water standard of 10mg/L) relative to <5mg/L. https://doi.org/10.1289/EHP8205  相似文献   
8.
Chronic rejection (CR) of liver allografts causes damage to intrahepatic vessels and bile ducts and may lead to graft failure after liver transplantation. Although its prevalence has declined steadily with the introduction of potent immunosuppressive therapy, CR still represents an important cause of graft injury, which might be irreversible, leading to graft loss requiring re-transplantation. To date, we still do not fully appreciate the mechanisms underlying this process. In addition to T cell-mediated CR, which was initially the only recognized type of CR, recently a new form of liver allograft CR, antibody-mediated CR, has been identified. This has indeed opened an era of thriving research and renewed interest in the field. Liver biopsy is needed for a definitive diagnosis of CR, but current research is aiming to identify new non-invasive tools for predicting patients at risk for CR after liver transplantation. Moreover, the minimization or withdrawal of immunosuppressive therapy might influence the establishment of subclinical CR-related injury, which should not be disregarded. Therapies for CR may only be effective in the “early” phases, and a tailored management of the immunosuppression regimen is essential for preventing irreversible liver damage. Herein, we provide an overview of the current knowledge and research on CR, focusing on early detection, identification of non-invasive biomarkers, immunosuppressive management, re-transplantation and future perspectives of CR.  相似文献   
9.
Sullivan  GW; Carper  HT; Mandell  GL 《Blood》1993,81(7):1863-1870
Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF.  相似文献   
10.
We evaluated the monthly distribution of rotavirus diarrhea in a cohort of children 12–24 months of age followed as part of a diarrhea clinical trial in a peri-urban community of Lima. We observed a peak of rotavirus diarrhea in the winter months and a decrease in rotavirus prevalence after the introduction of the rotavirus vaccine in Peru.  相似文献   
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