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Stent placement above the sphincter of Oddi might have advantages over stent placement across the sphincter of Oddi in prolonging stent patency in the treatment for malignant obstructive jaundice. To evaluate the role of bile flow patterns corresponding to biliary stent positioning in the process of stent occlusion in an in vitro bile perfusion model, one group of polyethylene stents was perfused continuously and another group of stents was perfused with additional flushing three times a day, simulating gallbladder emptying. After 8 weeks, the flow rates through the perfused stents were measured for evaluating the extent of stent occlusion indirectly. The results showed that bile flow rate of stents with additional flushing was significantly higher than the continuously perfused stents (P 0.01). It was demonstrated that after 18 hr of perfusion, additional flushing obviously decreased bacterial adherence to stent when compared to continuously perfused stents. In conclusion, flushing of bile may decrease the build-up of substance in vitro and thus improve stent flow rates, for which decreasing bacterial adherence to stents may be responsible. 相似文献
33.
Undraa Altangerel Sushma Rai Joann Fontanarosa Marlene R Moster 《Ophthalmic surgery, lasers & imaging》2006,37(2):106-111
BACKGROUND AND OBJECTIVE: To evaluate the intracameral use of Healon5 (2.3% sodium hyaluronate) (Advanced Medical Optics, Santa Ana, CA) in patients with hypotony. PATIENTS AND METHODS: Fifteen consecutive patients with glaucoma who had hypotony for at least 7 days were prospectively recruited. Indications for the intracameral injection of Healon5 were an intraocular pressure (IOP) of less than 6 mm Hg with negative results on Seidel test. RESULTS: The mean IOP readings at baseline, 1 to 2 weeks post-injection, and 4 to 6 weeks post-injection were 3.8 +/- 1.58, 6.58 +/- 2.62, and 6.50 +/- 2.24 mm Hg, respectively. The increase in IOP at both follow-up points was significant (P < .01). The visual acuity improvement was small but significant at the 4 to 6 week point (P = .05). In the early-onset cases, IOP increased significantly from baseline at both follow-up points (P< .05), but visual acuity did not. No significant change from baseline IOP or visual acuity occurred among the late-onset cases. The existing hypotony-related conditions consistently improved by the 4 to 6 week point. CONCLUSIONS: Intracameral injection of Healon5 raised IOP more in early-onset hypotony cases than in late-onset cases. Although the improvements in IOP and visual acuity were statistically significant, the overall clinical picture did not change because the endpoint IOP was still hypotonus. Twenty percent of the patients had IOP spikes that required medical treatment. 相似文献
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Connexin32 knockout mice (Cx32-KO) exhibit increased chemical- and radiation-induced liver and lung tumor formation with many lung tumors demonstrating decreased levels of the tumor suppressor p27KIP1. To determine if p27 deficiency alters Cx32-influenced tumorigenesis, we have generated a Cx32/p27 double-deficient mouse strain (DKO) and show here that exposure of these mice to X-ray radiation resulted in an increase or decrease in tumorigenesis depending on the tissue. Several tissues were highly sensitive to loss of p27 tumor suppressor function (intestine, adrenal, pituitary) resulting in an increased overall tumor burden in DKO mice compared to both wild-type (P<0.005) and Cx32-KO mice (P=0.066). However, additional deletion of p27 in a Cx32-KO background resulted in a statistically significant decrease in the liver tumor incidence suggesting that Cx32 and p27 pathways mechanistically interact. Immunohistochemical analysis revealed an increased percentage of Cx32-KO liver and lung tumors harboring active mitogen-activated protein kinase (Erk1, Erk2) pathways in contrast to lower percentages of activated wild-type (P<0.005) and DKO tumors (P=0.027). Increased MAPK activation in liver tumors did not correlate with Ha-ras codon-61 mutation status. This study demonstrates that tissues dependent on Cx32 tumor suppression, such as the liver and lung, exhibit altered tumorigenesis and tumor biology (MAPK pathway activation) related to p27 status. 相似文献
36.
Nekhlyudov L Bower M Herrinton LJ Altschuler A Greene SM Rolnick S Elmore JG Harris EL Liu A Emmons KM Fletcher SW Geiger AM 《Journal of the National Cancer Institute. Monographs》2005,2005(35):55-60
BACKGROUND: Contralateral prophylactic mastectomy (CPM) is the removal of a nonaffected breast in a woman with unilateral breast cancer and is effective in reducing the risk of recurrences. Little is known about women's decision-making roles regarding CPM. METHODS: Women aged 18-80 years with CPM performed at one of six health maintenance organizations between 1979 and 1999 were surveyed. We determined women's reported decision-making roles at the time of CPM, analyzed their trends over time, and explored the association between decision-making roles and psychosocial outcomes following CPM. RESULTS: We received 562 responses (response rate = 73%); 431 completed items needed for this analysis. Most respondents were white, younger than 55 years at CPM, married, and had CPM within 10 years of completing the survey. Forty-five percent made the decision to undergo CPM alone, 37% considered their doctor's opinion, 15% shared the decision with their doctor and only 3% reported their doctor primarily made the decision. Women reporting active roles were more likely to be younger (P<.0008), college educated (P<.0001) and have CPM more recently (P = .002). Compared with those sharing the decision with their doctors, women with active roles were twice as likely to be satisfied 6 months following CPM (odds ratio [OR] = 2.2, 95% confidence interval [CI] = 1.1 to 4.2) and report current concern about breast cancer (OR = 1.9, 95% CI = 1.0 to 3.4). CONCLUSIONS: Most women reported active or shared roles in decision making regarding CPM, particularly younger women, those with college education, and those with recent CPM. Women with active roles were more often satisfied in the short term but were also more likely to report current concern about breast cancer. Whether higher concern is related to insufficient input from clinicians should be explored. Prospective data are needed. 相似文献
37.
Barton MB West CN Liu IL Harris EL Rolnick SJ Elmore JG Herrinton LJ Greene SM Nekhlyudov L Fletcher SW Geiger AM 《Journal of the National Cancer Institute. Monographs》2005,2005(35):61-66
BACKGROUND: Bilateral prophylactic mastectomy significantly decreases breast cancer risk, but complications of the procedure have only been described in single-site studies. We describe the frequency and type of complications in women who underwent bilateral prophylactic mastectomy in a multisite community-based cohort. METHODS: Women aged 18-80 years undergoing bilateral prophylactic mastectomy without a personal history of breast cancer at one of six health plans were eligible. We identified women from automated data sources, then reviewed hospital data, ambulatory notes, and other chart elements to confirm eligibility and obtain all charted information about complications and surgeries performed after prophylactic mastectomy, including reconstructive procedures. Reconstructions were characterized by type (implant vs. tissue graft). Complications were noted for a 1-year period after any surgical procedure. RESULTS: We identified 269 women with prophylactic mastectomy who were followed for a mean of 7.4 years. Their mean age was 44.9 years. Nearly 80% undertook reconstruction, most with prosthetic implants. One or more complications occurred in 64%. The most common complications were pain (35% of women), infection (17%), and seroma (17%). Women with no reconstruction had fewer complications (mean of .93) than women who had implant (2.0) or tissue graft (2.4) reconstruction procedures (differences from no reconstruction: 1.07 [95% confidence interval = 0.36 to 1.77] and 1.50 [95% confidence interval = 0.44 to 2.56] respectively). Delay of reconstruction after mastectomy was associated with a borderline-significant higher risk of complications (80.6%) compared to simultaneous reconstruction (64.0%, P = .055). CONCLUSION: We found that almost two-thirds of women undergoing bilateral prophylactic mastectomy had at least one complication following surgery. Further work should be done to minimize and to understand the effect of complications of bilateral prophylactic mastectomy. 相似文献
38.
McDonald JM See SJ Tremont IW Colman H Gilbert MR Groves M Burger PC Louis DN Giannini C Fuller G Passe S Blair H Jenkins RB Yang H Ledoux A Aaron J Tipnis U Zhang W Hess K Aldape K 《Cancer》2005,104(7):1468-1477
BACKGROUND: It has been reported previously that the combined loss of chromosomal arms 1p and 19q is a significant predictor of outcome for patients with anaplastic oligodendroglial (AO) tumors and that such chromosomal loss correlates with classic histology in AO. The authors sought to determine whether histology was an equivalent or superior predictor of outcome compared with 1p/19q status in 131 patients with AO tumors. METHODS: The status of 1p and 19q was determined using real-time, quantitative polymerase chain reaction analysis and/or fluorescence in situ hybridization. Clinical features (response to adjuvant therapy and tumor location) and molecular genetic abnormalities (9p and 10q deletions, overexpression of p53 and epidermal growth factor receptor) were determined on available specimens. Histologic assessments for classic oligodendroglial features were performed by five neuropathologists. RESULTS: Classic histology was associated closely with 1p/19q loss, as reported previously. Patients who had tumors that were considered classic by at least four of the five neuropathologists showed significantly increased progression-free and overall survival compared with the patients who had less classic tumors. The authors also tested the correlation between 1p/19q status and outcome in subsets of patients stratified according to classic tumor features. The association of 1p/19q status with survival was related closely to the presence of classic histology. Loss of 1p/19q was predictive of improved outcome only among patients who had tumors with classic histologic features. CONCLUSIONS: The current results suggested that, in addition to 1p/19q status, histologic features contribute information to the prediction of outcome in patients with AO. Loss of 1p and 19q appeared to be a prognostic marker only in the subset of patients who had AO tumors with classic histologic features. 相似文献
39.
This study investigates the use of a range of conversational strategies in a nurse-led socialization group with long-term care residents who have dementia. Eight residents whose Mini-Mental State Examination (MMSE) scores ranged from 0 to 19 participated in weekly group sessions for 10 weeks. All sessions were tape recorded and transcribed verbatim. Analysis of transcribed sessions resulted in two taxonomies: a taxonomy of nurse conversational strategies (clarifying, exploring, moderating, validating, rescuing, and general discourse markers) and a taxonomy of patient responses (discourse markers, limited engagement, expanded responses, personalized response, self-initiated participation, and disconnected or fragmented participation). The effectiveness of the nurse conversational strategies was reflected in the encouraging level of resident participation rates. The findings of this study suggest that with effective support and prompting, patients with advanced dementia are able to engage in social conversations beyond what would be expected given their diagnosis and MMSE scores. 相似文献
40.
Schwartz MD Basco WT Grey MR Elmore JG Rubenstein A 《Annals of internal medicine》2005,142(8):715-724
Despite changes in the structure of the U.S. health care system, patients continue to need and seek out generalist physicians. However, the proportion of U.S. graduates of medical schools who choose to enter generalist residency training decreased from 50% in 1998 to less than 40% in the 2004 match. Unless we act now to reverse this trend, we may face a shortage of primary care physicians to care for the complex medical needs of an aging population. This article reviews the history of and trends in career choice and proposes 4 evidence-based recommendations to rekindle student interest in generalist careers: 1) We must improve satisfaction and enthusiasm among generalist physician role models. 2) Schools of medicine should redouble their efforts to produce primary care physicians. 3) We must facilitate the pathway from medical school to generalist residency. 4) The U.S. government should increase funding for primary care research and research training. In the absence of a major overhaul of economic incentives in favor of generalist careers, we will need to work at these multiple levels to restore balance to the generalist physician workforce and align with the desires and expectations of patients for continuing healing relationships with generalist physicians. 相似文献