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61.
Flexible Sigmoidoscopy Screening in an Industrial Setting 总被引:1,自引:0,他引:1
Benjamin Krevsky M.D. M.P.H. F.A.C.G. Tomasz Niewiarowski M.D. Rita League R.N. Harold Herman M.D. Lisa Matz Robert S. Fisher M.D. F.A.C.G. 《The American journal of gastroenterology》1992,87(12):1759-1762
Little is known about the yield of colorectal cancer screening programs in an industrial setting. We therefore established a flexible sigmoidoscopy screening program at a chemical manufacturing plant and offered testing to all employees over the age of 40. After a Fleet enema preparation had been administered, a digital rectal examination and sigmoidoscopy were performed on each volunteer worker in the medical office of the plant. The plant had an average census of about 650 workers; 202 were screened during a 2-yr period. The mean (+/- SEM) age of participants was 52 +/- 0.4. Sixty-four employees had polyps (31.7%); data on follow-up colonoscopy were available in 69%. Colonoscopy revealed adenomatous polyps in 23 workers (53.5%), hyperplastic polyps in 10 (23%), and no evidence of neoplasia in 10 (23%). Seven workers did not arrange for follow-up colonoscopy and 12 individuals could not be contacted. No cancers were detected. In the 40- to 50-yr age group, polyps were detected in 19.5% of employees (25% adenomatous). Incidental findings were common, and included prostatic nodules, hemorrhoids, diverticulosis, and proctitis, among others. We conclude that screening sigmoidoscopy can be conveniently and economically performed at the workplace, with a high yield and good worker acceptance. The high yield suggests a possible association between polyp formation and work in a chemical plant. The finding of adenomatous polyps in the younger patients suggests that the threshold for flexible sigmoidoscopy at age 50 needs to be reassessed. 相似文献
62.
Molecular cloning and functional expression of two monocyte chemoattractant protein 1 receptors reveals alternative splicing of the carboxyl-terminal tails. 总被引:45,自引:0,他引:45 下载免费PDF全文
I F Charo S J Myers A Herman C Franci A J Connolly S R Coughlin 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(7):2752-2756
Monocyte chemoattractant protein 1 (MCP-1) is a member of the chemokine family of cytokines that mediate leukocyte chemotaxis. The potent and specific activation of monocytes by MCP-1 may mediate the monocytic infiltration of tissues in atherosclerosis and other inflammatory diseases. We have isolated cDNAs that encode two MCP-1-specific receptors with alternatively spliced carboxyl tails. Expression of the receptors in Xenopus oocytes conferred robust mobilization of intracellular calcium in response to nanomolar concentrations of MCP-1 but not to related chemokines. The MCP-1 receptors are most closely related to the receptor for the chemokines macrophage inflammatory protein 1 alpha and RANTES (regulated on activation, normal T expressed and secreted). The identification of the MCP-1 receptor and cloning of two distinct isoforms provide powerful tools for understanding the specificity and signaling mechanisms of this important chemokine. 相似文献
63.
Uttam C. Garg Lakshmi Devi Herman Turndorf Lewis R. Goldfrank Mylarrao Bansinath 《Brain research》1992,592(1-2):208-212
In the brain, nitric oxide (NO) has been identified as a messenger molecule and a mediator of excitatory amino acid-induced neurotoxicity. In this study, the effects of NO on serum-induced mitogenesis and cell proliferation of the cerebellar glial cells were assessed. NO-generating agent, S-nitroso-N-acetylpenicillamine (SNAP) increased intracellular cyclic guanosine monophosphate (cGMP) levels. Furthermore, 2 chemically dissimilar NO-generating agents, SNAP and sodium nitroprusside (SNP) inhibited serum-induced thymidine incorporation and cell proliferation. The antimitogenic effect of NO was mimicked by 8-bromo-cGMP and blocked by hemoglobin, a known inhibitor of NO. The effect of NO was not cytotoxic, since the cells were not stained with Trypan blue and did not show increased release of lactate dehydrogenase in the culture supernatants. However, NO-treated cells showed decreased conversion of tetrazolium to blue formazan suggesting that NO inhibited mitochondrial activity in the glial cells. These results demonstrate that NO inhibits serum-induced mitogenesis and cell proliferation of cultured rat cerebellar glial cells. 相似文献
64.
Guilherme Janson Karina Santana Cruz Donald G Woodside Angelos Metaxas Marcos Roberto de Freitas José Fernando Castanha Henriques 《American journal of orthodontics and dentofacial orthopedics》2004,126(4):451-463
The objective of this study was to evaluate the dentoskeletal changes consequent to orthodontic treatment in subjects with Class II subdivision malocclusions, treated with asymmetric extractions, compared with a normal-occlusion control group. The sample consisted of 3 groups, with 30 subjects in each: normal-occlusion subjects (group 1), untreated Class II subdivision subjects (group 2), and Class II subdivision patients treated with asymmetric extractions (group 3). All subjects had a full complement of permanent teeth at the beginning of treatment. The average ages of the subjects were 22.42, 15.76, and 18.57 years, respectively, in groups 1, 2, and 3. Measurements of relative differences in the spatial position of dental and skeletal bilateral landmarks were obtained from the submentovertex and posteroanterior cephalometric (PA) radiographs. The t test for independent samples was used to compare group 1 with groups 2 and 3 at different times. Results from the submentovertex radiograph showed that asymmetric extractions in Class II subdivision malocclusions will maintain the differences in the anteroposterior positions of right and left, maxillary and mandibular first molars, as would be expected with the treatment protocols used. There were no significant skeletal changes that could be attributed to the treatment approaches investigated or transverse collateral effects with the asymmetric mechanics used. It was also demonstrated that treatment of Class II subdivision malocclusions with asymmetric extractions produced corrections of maxillary and mandibular dental midline deviations with the midsagittal plane, without canting the occlusal plane or any other investigated horizontal plane, as seen in the PA radiograph. Treatment of Class II subdivision malocclusions with asymmetric extractions constitutes a beneficial approach to this problem. 相似文献
65.
Alfredo Avellaneda Fernández álvaro Pérez Martín Maravillas Izquierdo Martínez Mar Arruti Bustillo Francisco Javier Barbado Hernández Javier de la Cruz Labrado Rafael Díaz-Delgado Pe?as Eduardo Gutiérrez Rivas Cecilia Palacín Delgado José Ramón Ramón Giménez Javier Rivera Redondo 《Atencion primaria / Sociedad Espa?ola de Medicina de Familia y Comunitaria》2009,41(10):e1-e5
66.
Ana Teresa Timóteo Andreia Mamede Maria de Lurdes Ferreira José Serra José Alberto Oliveira Rui Cruz Ferreira Jorge Quininha 《Revista portuguesa de cardiologia》2007,26(2):135-143
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction. 相似文献
67.
Eugene L. Dela Cruz DPM FACFAS Greg R. Brockbank DPM 《The Journal of foot and ankle surgery》2005,44(4):311-312
Talar dome lesions greater than 1 cm in diameter are often treated with ankle joint mosaicplasty. The purpose of this article is to present the use of a noninvasive ankle distractor that can improve access to the talus when used with a malleolar osteotomy. The use of the distractor allows for graft insertion at a more appropriate angle in relationship to the talar cartilage, avoidance of invasive distractor usage, and potential use of a smaller osteotomy. 相似文献
68.
Lia Assumpcao John L. Cameron Christopher L. Wolfgang Barish Edil Michael A. Choti Joseph M. Herman Jean-Francois Geschwind Kelvin Hong Christos Georgiades Richard D. Schulick Timothy M. Pawlik 《Journal of gastrointestinal surgery》2008,12(11):1915-1923
Background
No data on incidence, management, or natural history of chyle leaks following pancreatic resection have been published. We
sought to identify possible risk factors associated with chyle leaks following pancreatic resection, as well as determine
the natural history of this rare complication.
Methods
Between 1993 and 2008, 3,532 patients underwent pancreatic resection at a single institution. Data on demographics, operative
details, primary tumor status, and chyle leak were collected. To identify risk factors associated with chyle leak, a matched
3:1 paired analysis was performed.
Results
Of 3,532 patients undergoing pancreatic resection, 47 (1.3%) developed a chyle leak (n = 34, contained chyle leak versus n = 13, diffuse chylous ascites). Chyle leak was identified at median 5 days following surgery. Median drain triglyceride levels
were 592 ng/dl. After matching on tumor size, disease etiology, and resection type, the number of lymph nodes harvested and
history of concomitant vascular resection predicted higher risk of chyle leak (both P < 0.05). Total parenteral nutrition (TPN) was required in more patients with chylous ascites (92.3%) than those with chyle
leaks (44.1%) (P = 0.003). The median time to resolution was shorter for contained chyle leaks (13 days) versus chylous ascites (36 days)
(P < 0.001). Patients with chylous ascites tended to have shorter overall survival (3-year, 18.8%) versus patients with no chyle
leak (3-year, 46.9%) (P = 0.12). In contrast, patients with a contained chyle leak had a similar survival as patients with no chyle leak (3-year,
53.4% versus 46.9%, respectively) (P = 0.32).
Conclusion
Chyle leak was a rare (1.3%) complication following pancreatic resection that was associated with number of lymph nodes harvested
and concomitant vascular resection. In general, chyle leaks were successfully managed with TPN with no adverse impact on outcome.
Patients with chylous ascites, however, had a more protracted clinical course and tended to have a worse long-term survival.
Presented at the Society for Surgery of the Alimentary Tract, 49th Annual Meeting, San Diego, CA, May 18th, 2008
Support: Dr. Pawlik is supported by Grant Number 1KL2RR025006-01 from the National Center for Research Resources (NCRR), a
component of the National Institutes of Health (NIH), and NIH Roadmap for Medical Research. The contents of this publication
are solely the responsibility of the authors and do not necessarily represent the official view of NCRR or NIH. 相似文献
69.
70.
OBJECTIVE: Persistent vertigo and imbalance can occur after surgery for vertigo regardless of surgical approach. This study explored for factors affecting outcome of vertigo surgery. STUDY DESIGN: Patient survey and chart review. SETTING: Tertiary referral neurotologic private practice. PATIENTS/INTERVENTION: Of 111 patients (57.7% female; mean age, 52.3 yr), 59 underwent vestibular nerve section (middle fossa, retrolabyrinthine, and translabyrinthine), 25 underwent transmastoid labyrinthectomy, and 27 underwent endolymphatic sac shunt. Eighty-three percent had Ménière's disease. Mean follow-up was 4.3 years. MAIN OUTCOME MEASURES: Primary outcomes included American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) vertigo score and class, number of spells per month, current and change in AAO-HNS disability rating, vertigo and imbalance severity ratings, and frequency of imbalance. RESULTS: Three preoperative factors were consistently related to outcome: AAO-HNS disability rating, imbalance frequency rating, and duration of first symptom ([rho] = 0.19-0.51; all p's < 0.05). Greater disability and more frequent imbalance related to poorer outcome, but longer duration of disease related to better outcome. Presurgery vertigo characteristics were generally not related to outcome. Ménière's patients were more likely to have improvement in imbalance, as were those with no other significant disease and no allergy. The presence of tinnitus in the contralateral ear was associated with poorer outcomes, including a lower rate of results of Classes A and B (p = 0.023). Vertigo as a first symptom and the presence of eye disease also showed relationships to poorer outcome. CONCLUSION: Those rating themselves as more disabled before surgery are less likely to achieve the best outcomes, whereas frequency and severity of preoperative vertigo are not predictive. Several possible prognostic factors were identified that warrant future prospective study. 相似文献