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排序方式: 共有757条查询结果,搜索用时 10 毫秒
1.
Intraoperative penile tumescence during endoscopic surgery is a troublesome complication that often is refractory to recommended methods of management. We report a new approach of pharmacological management with intracorporeal penile injections of phenylephrine (total dose of 0.1 mg.), which was successful in 3 successive patients. This approach is prompt, safe and reproducible, and it provides sustained resolution of erection without systemic side effects. It is concluded that local intracorporeal penile administration of this sympathomimetic agent appears to be a potent new tool in the armamentarium of the endoscopic surgeon dealing with this frustrating clinical situation, which merits further clinical trial. 相似文献
2.
Sinonasal surfactant protein A1, A2, and D gene expression in cystic fibrosis: a preliminary report. 总被引:1,自引:0,他引:1
Bradford A Woodworth Rachel Wood John E Baatz Rodney J Schlosser 《Otolaryngology--head and neck surgery》2007,137(1):34-38
OBJECTIVE: To measure alterations in SPA1, A2, and D gene expression in various forms of inflammatory chronic rhinosinusitis (CRS). STUDY DESIGN AND SETTING: Sinus mucosal biopsies were performed in patients with allergic fungal rhinosinusitis (AFS), CRS with nasal polyposis, cystic fibrosis (CF), and controls. SP mRNA was measured with quantitative polymerase chain reaction. RESULTS: Patients with CF (n = 4) showed significantly increased SPA1 (82-fold), SPA2 (100-fold), and SPD (47-fold) mRNA (P < 0.05) when compared with controls (n = 5). Patients with CRS with nasal polyposis (n = 5) also demonstrated elevated SPA1 (27-fold), SPA2 (13-fold), and SPD (13-fold). Patients with AFS (n = 7) had increased SPA1 (5-fold), SPA2 (9-fold), and SPD (17-fold), but were not statistically significant. CONCLUSION: SPA1, A2, and D are upregulated in various forms of CRS, but are significantly elevated in cystic fibrosis CRS. SIGNIFICANCE: Understanding the role of SPs in CRS will help develop novel treatment approaches for sinonasal pathoses. 相似文献
3.
Induction of squamous metaplasia in organ cultures of hamster trachea by naturally occurring and synthetic fibers 总被引:6,自引:0,他引:6
Asbestos exhibits many properties of classical tumor promoters. These characteristics include the ability to stimulate proliferation and inhibit normal differentiation of cells. In organ cultures of trachea, crocidolite and amosite asbestos stimulate squamous metaplasia, a pathological process in which a rapidly proliferating squamous epithelium replaces the normal epithelium. We hypothesized that the induction of metaplasia depends upon the fibrous nature of asbestos. Accordingly, several naturally occurring and synthetic fibrous materials and their nonfibrous analogues were assessed for their ability to induce metaplastic changes in tracheal mucosa of the Syrian hamster. Exposure to both crocidolite asbestos and fiberglass resulted in significant increases (p less than 0.05) in squamous metaplasia over a range of dosages (1.0, 4.0, 16.0 mg/ml). Attapulgite (palygorskite) and both "long-" and "short-" fiber preparations of chrysotile asbestos had similar but less marked effects. Nonfibrous analogues of each material (riebeckite, antigorite, and glass particles) failed to produce metaplasia. Asbestos, and fibrous materials in general, appear to stimulate squamous metaplasia because of their fibrous geometry. 相似文献
4.
Licciardone JC Herron KM Marshall MA Woodworth RM 《The Journal of the American Osteopathic Association》2000,100(7):423-4, 427-31
Travel medicine practice in the United States has not been extensively studied. This study included 1078 consecutive patients who presented to a university-based travel medicine clinic from 1990 through 1994. Analyses of patient demographics, clinic attendance, itineraries, and vaccinations were conducted. Mean patient age (+/- SD) was 37.4 +/- 16.2 years; 626 (58.1%) of the patients were male. Travel duration was 103.1 +/- 242.3 days (median, 21 days), and lead time (defined as the time between clinic presentation and departure for the purpose of this study) was 23.8 +/- 26.5 days (median, 16 days). Destination was the strongest independent factor affecting vaccination practices. A lead time of 31 or more days was associated with significantly elevated odds ratios for all immunobiologicals except immune globulin. These findings underscore the need to educate the traveling public, healthcare providers, and the travel industry about the benefits of seeking medical consultation at least 1 month prior to international travel. 相似文献
5.
Hydrogen peroxide inhibits gap junctional intercellular communication in glutathione sufficient but not glutathione deficient cells 总被引:7,自引:5,他引:7
Cell to cell communication via gap junctions is essential in the
maintenance of the homeostatic balance of multicellular organisms. Aberrant
intercellular gap junctional communication (GJIC) has been implicated in
tumor promotion, neuropathy and teratogenesis. Oxidative stress has also
been implicated in similar pathologies such as cancer. We report a
potential link between oxidative stress and GJIC. Hydrogen peroxide, a
known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells
with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible
as indicated by the complete recovery of GJIC with the removal of H2O2 via
a change of fresh media. Free radical scavengers, such as t-butyl alcohol,
propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2,
which indicated that the effects of H2O2 on GJIC was probably not a
consequence of aqueous free radical damage. The depletion of intracellular
GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of
glutathione- sufficient cells with H2O2 resulted in the
hyperphosphorylation of connexin43, which is the basic subunit of the
hexameric gap junction protein, as determined by Western blot analysis.
TPA, a well-known tumor promoter, also inhibits GJIC via
hyperphosphorylation of GJIC, which is a result of protein kinase-C
activation. However, H2O2 also induced hyperphosphorylation in
GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism
of GJIC inhibition must be different from the TPA-pathway and involves GSH.
相似文献
6.
BACKGROUND: To evaluate debt and other factors that help formulate the career paths of future surgical and primary care physicians, a survey was undertaken. METHODS: Surgical specialty (SS) and primary care (PC) residents were surveyed regarding demographics, factors influencing choice of specialty, methods of financing education, debt characteristics, and outlooks regarding future earnings and practice characteristics. RESULTS: The clinical years of medical school and personalities of specialists and residents were important factors in career choices for both PC and SS. The length of residency, desirable lifestyle, and working hours were all more important to PC residents. Surgeons found intellectual challenge and procedure-based practice of greater importance. Although not highly regarded by either group, scholarship obligation and student loans had a significantly greater impact on specialty choice and practice plans for PC residents. At the completion of training, 55% of SS and 28% of PC residents anticipate owing more than $100,000. Debt was especially significant in specialty choice and practice plans for PC residents with debt over $100,000. CONCLUSION: Surgical residents are less concerned about personal sacrifices in their quest to become surgeons. It appears state funded scholarships are successful in attracting students to primary care. Both SS and PC residents have significant debt, although, SS residents have greater financial debt than primary care residents. However, the anticipation of indebtedness was a more significant factor in determination of career path for PC. 相似文献
7.
Woodworth PA McBoyle MF Helmer SD Beamer RL 《The American surgeon》2000,66(5):444-50; discussion 450-1
The pathophysiology of seroma formation has yet to be determined. Therefore, the present study was undertaken to calculate the incidence of postoperative seromas after definitive breast cancer operations utilizing electrocautery dissection. Additionally, we attempted to identify risk factors associated with seroma development and to examine seroma formation in relation to operative procedure. A retrospective review of 252 breast cancer operations was undertaken. Patients were subdivided by operative procedure: modified radical mastectomy (MRM; n = 148), breast preservation with axillary node dissection (n = 64), or MRM with immediate reconstruction (n = 40). Electrocautery was used in development of skin flaps. Seromas developed in 39 of the 252 operations for an incidence of 15.5 per cent. Seroma formation was significantly lower in those patients receiving MRM with immediate reconstruction than in those receiving MRM (2.5% vs 19.6%; P = 0.009) and tended to be lower than for patients receiving breast preservation with axillary node dissection (14.06%; P = 0.052). Neoadjuvant chemotherapy was performed in 18 patients, of whom 6 developed seromas (P = 0.030). The incidence of postoperative seromas was low despite the use of electrocautery. An association of postoperative seromas with neoadjuvant chemotherapy was noted. Additionally, it appears that immediate reconstruction may reduce the incidence of postoperative seromas, presumably by filling the dead space in the chest wall. 相似文献
8.
l‐Methionine anti‐biofilm activity against Pseudomonas aeruginosa is enhanced by the cystic fibrosis transmembrane conductance regulator potentiator,ivacaftor 下载免费PDF全文
Calvin Mackey BS Christopher G. Weeks BS Jaime A. Peña Garcia BS Daniel Skinner BS Jessica W. Grayson MD Harrison S. Hill BS David K. Alexander Shaoyan Zhang PhD Bradford A. Woodworth MD 《International forum of allergy & rhinology》2018,8(5):577-583
Background
Biofilms may contribute to refractory chronic rhinosinusitis (CRS), as they lead to antibiotic resistance and failure of effective clinical treatment. l ‐Methionine is an amino acid with reported biofilm‐inhibiting properties. Ivacaftor is a cystic fibrosis transmembrane conductance regulator (CFTR) potentiator with mild antimicrobial activity via inhibition of bacterial DNA gyrase and topoisomerase IV. The objective of this study was to evaluate whether co‐treatment with ivacaftor and l ‐methionine can reduce the formation of Pseudomonas aeruginosa biofilms.Methods
P aeruginosa (PAO‐1 strain) biofilms were studied in the presence of l ‐methionine and/or ivacaftor. For static biofilm assays, PAO‐1 was cultured in a 48‐well plate for 72 hours with stepwise combinations of these agents. Relative biofilm inhibitions were measured according to optical density of crystal violet stain at 590 nm. Live/dead assays (BacTiter‐Glo? assay, Promega) were imaged with laser scanning confocal microscopy. An agar diffusion test was used to confirm antibacterial effects of the drugs.Results
l ‐Methionine (0.5 μM) significantly reduced PAO‐1 biofilm mass (32.4 ± 18.0%; n = 4; p < 0.001) compared with controls. Low doses of ivacaftor alone (4, 8, and 12 μg/mL) had no effect on biofilm formation. When combined with ivacaftor (4 μg/mL), a synergistic anti‐biofilm effect was noted at 0.05 μM and 0.5 μM of l ‐methionine (two‐way analysis of variane, p = 0.0415) compared with corresponding concentrations of l ‐methionine alone.Conclusion
Ivacaftor enhanced the anti‐biofilm activity of l ‐methionine against the PAO‐1 strain of P aeruginosa. Further studies evaluating the efficacy of ivacaftor/l ‐methionine combinations for P aeruginosa sinusitis are planned.9.
Angiogenic factors stimulate mast-cell migration 总被引:18,自引:1,他引:18
Mast cells accumulate at sites of angiogenesis. The factor(s) that control mast-cell recruitment at these sites have yet to be defined. We sought to determine if angiogenic factors result in mast-cell chemotaxis. In this study, we observed that platelet-derived growth factor-AB (PDGF-AB), vascular endothelial cell growth factor (VEGF), and basic fibroblast growth factor (bFGF) each cause directed migration of murine mast cells at picomolar concentrations, with a typical bell- shaped dose-response curve. Another potent angiogenic factor, platelet- derived endothelial cell growth factor (PD-ECGF), appears to promote chemokinesis of mast cells, whereas tumor necrosis factor-alpha, a weak angiogenic factor, is less robust but still functions as a mast cell chemotactic factor. Epidermal growth factor (EGF), a growth factor with minimal angiogenic properties, was ineffective as a mast cell chemotactic factor. A checkerboard analysis confirmed the directional chemotactic response of PDGF-AB, VEGF, and bFGF, while indicating the chemokinetic response induced by PD-ECGF. Cross-desensitization of growth-factor-induced directed migration was observed between PDGF-AB and bFGF, and also between PDGF-AB and PD-ECGF. Tyrosine kinase- inhibitor genistein effectively dampened the chemotactic responses, whereas pertussis toxin had no effect. In summary, our findings suggest that factors known to act on endothelial cells and stimulate neovascularization may simultaneously serve to recruit mast cells to these sites. The local accumulation of mast cells is believed to facilitate new vessel formation through complex cell:cell interactions. 相似文献
10.
Spontaneous sphenoid lateral recess cerebrospinal fluid leaks arise from intracranial hypertension,not Sternberg's canal 下载免费PDF全文