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81.
82.
OBJECTIVE: Cancer Care Ontario has recommended a program to screen for colorectal cancer using fecal occult blood testing (FOBT). Patients who test positive on FOBT will require further investigation. We examined the cost of finding an advanced adenoma in these patients using four different strategies. METHODS: Using decision analysis software (DATA 3.5, TreeAge Software, Boston, MA), we considered four strategies for evaluating patients referred for a positive FOBT: 1) flexible sigmoidoscopy to the splenic flexure, 2) flexible sigmoidoscopy with air contrast barium enema (ACBE), 3) virtual colonoscopy, and 4) colonoscopy. If an adenoma was found in any of the first three methods, colonoscopy and polypectomy were performed. An advanced adenoma was defined as a villous adenoma, tubular adenoma > or = 10 mm, high grade dysplasia, or cancer. Values for probabilities, test characteristics and costs ($CDN) were estimated from a MEDLINE literature review, local costs, and OHIP fee codes. Patients with adenomas identified as well as direct medical costs from a third party payer perspective were calculated. RESULTS: Assuming a probability of adenoma of 16.9%, the cost for each strategy (compared to no investigation) was as follows: flexible sigmoidoscopy to the splenic flexure, $226; flexible sigmoidoscopy with ACBE, $424; virtual colonoscopy, $597; and colonoscopy, $387. The cost to clear a patient of adenoma(s) was $1,930, $2,840, $3,681, and $2,290, respectively. Despite being most cost-effective, the sigmoidoscopy strategy was predicted to detect 69% of cases of advanced adenomas. The radiological strategies would be less expensive if ACBE cost less than $115 or virtual colonoscopy cost less than $291. The colonoscopy strategy was more cost-effective if the probability of an adenoma was > or = 33.5%. When the incremental costs were considered to investigate 1000 patients, virtual colonoscopy and sigmoidoscopy with ACBE were both more costly then colonoscopy, and neither detected as many cases of advanced adenomas. CONCLUSION: Improved access to colonoscopy seems to be the preferred approach to deal with increased referrals. 相似文献
83.
C. I. Johnston R. Iansek † J. A. Millari ‡ B. P. McGrath P. G. Matthews † † 《Internal medicine journal》1981,11(6):59-63
Abstract: Angiotensin converting enzyme plays a key role in the hormonal regulation of blood pressure. It is responsible for the production of the vasconstrictor hormonal peptide angiotensin II as well as the destruction of the vasodilator peptide bradykinin. Recently, orally active specific inhibitors of angiotensin converting enzyme have become available. Captopril (SQ14225) blocks angiotensin I and potentiates bradykinin effects in vitro and in vivo. In man it leads to a fall in endogenous plasma angiotensin II , a rise in blood angiotensin I and renin, but no change in blood bradykinin can be detected .
In sodium deplete normal subjects it lowers the blood pressure, but in sodium replete subjects it is without effect. Similarly, it will acutely lower blood pressure in renovascular and accelerated hypertension but not in essential hypertension. The acute hypotensive effect of captopril may therefore be due to inhibition of the renin-angiotensin system .
However, in the long term, it is effective in lowering the blood pressure in patients with essential hypertension, especially when combined with a diuretic. This suggests that the long-term hypotensive effect differs from the short term effect, and involves mechanisms other than inhibition of the renin-angiotensin 相似文献
In sodium deplete normal subjects it lowers the blood pressure, but in sodium replete subjects it is without effect. Similarly, it will acutely lower blood pressure in renovascular and accelerated hypertension but not in essential hypertension. The acute hypotensive effect of captopril may therefore be due to inhibition of the renin-angiotensin system .
However, in the long term, it is effective in lowering the blood pressure in patients with essential hypertension, especially when combined with a diuretic. This suggests that the long-term hypotensive effect differs from the short term effect, and involves mechanisms other than inhibition of the renin-angiotensin 相似文献
84.
Differential renal function during angiotensin converting enzyme inhibition in renovascular hypertension 总被引:1,自引:0,他引:1
Renal function was measured sequentially in 32 patients with proven renovascular hypertension who were treated with the oral angiotensin converting enzyme inhibitor captopril. Renal function was assessed by serial measurement of serum creatinine. Six patients showed acute rises in serum creatinine concentration compatible with acute renal failure. Acute renal failure was confined to those patients with stenosis to a solitary kidney (transplant or native, occurring in 3 of 8 patients) or bilateral renal artery stenosis (occurring in 3 of 13 patients). No rise in serum creatinine concentration was observed in 11 patients with unilateral renal artery stenosis during long-term angiotensin converting enzyme inhibitor therapy. Acute renal failure during angiotensin converting enzyme inhibitor therapy was not related to the degree of blood pressure fall or the plasma angiotensin II level. Eleven patients with renovascular hypertension were followed prospectively with estimation of renal function by 99mTc-diethylenetriaminepentaacetic acid (DTPA) clearance (determined by computer analysis of scintillation camera renography). In six patients with unilateral renal artery stenosis, total 99mTc-DTPA clearance and serum creatinine level remained constant following angiotensin converting enzyme inhibitor therapy, while in five patients with bilateral renal artery stenosis 99mTc-DTPA clearance fell from 40 +/- 9 to 27 +/- 5 ml/min (p less than 0.05). Split renal function studies revealed that 99mTc-DTPA clearance fell in most kidneys with stenosed arteries during angiotensin converting enzyme inhibition, including the stenosed kidney from patients with unilateral renal artery stenosis (16 stenosed kidneys studied; change in Tc-DTPA clearance, -7.5 +/- 2.7 ml/min).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
85.
Summary Studies of homograft valves in the past two decades have suggested that viable valves, i.e., those maintaining chemical and structural integrity of their leaflet intercellular matrix, have a better long-term function than nonviable valves. The most effective qualitative methods of assessing leaflet viability involve destruction of the valve leaflets; thus, these methods have been limited to random use in selected valves. A study was conducted in swine in an attempt to establish a control tissue which could be tested in place of the homograft leaflets, thereby determining viability levels of every valve clinically implanted and correlating the results with long-term clinical function. Thirty samples each of the aortic and pulmonary artery wall and tricuspid leaflet were compared with aortic and pulmonary leaflets. Utilizing the technique of C14-proline uptake, viability was assessed at procurement, following sterilization, and following cryopreservation and short-term storage. The tricuspid leaflet was found to retain the same level of viability as the aortic and pulmonary leaflets before and after the cryopreservation period. It was concluded that the tricuspid leaflet could be utilized as the control tissue. 相似文献
86.
McGrath LB Chen C Bailey BM Cha SD Fernandez J Laub GW Adkins MS 《The Journal of invasive cardiology》1991,3(1):35-40
Of 530 patients undergoing tricuspid valve surgery from January 1, 1961 through December 31, 1987, those 362 patients having had preoperative right ventricular angiocardiography were studied. Mean age was 58.5 years. There were 71 males and 291 females. Tricuspid valve replacement (TVR) was performed in 126 (34.8%), and 236 underwent tricuspid valve repair (65.2%). The predominant pathology was combined tricuspid insufficiency and stenosis in 18 patients (4.9%), and isolated tricuspid insufficiency in 344 (95.1%). There were no complications related to the right ventriculogram. Preoperative angiographic severity of tricuspid valve incompetence was grade 1 in 23 patients (6.4%), grade 2 in 65 (17.9%), grade 3 in 109 (30.1%), and grade 4 in 165 (45.6%). Intraoperative assessment of the severity of tricuspid valve incompetence correlated 72% of the time with the preoperative angiographic assessment, in those patients with more severe degrees of incompetence (grade 3+ or 4+), p (X 2) less than 0.001. Increasing severity of preoperative angiographic triscuspid valve incompetence was associated with the requirement for TVR (vs. repair), p (X 2) = 0.0002. In conclusion, preoperative right ventricular angiography is a useful method for assessing tricuspid valve function and may predict the requirement for TVR in patients undergoing tricuspid valve surgery. 相似文献
87.
Kranzer K McGrath N Saul J Crampin AC Jahn A Malema S Mulawa D Fine PE Zaba B Glynn JR 《Tropical medicine & international health : TM & IH》2008,13(11):1341-1350
Objective To investigate individual, household and community factors associated with HIV test refusal in a counselling and testing programme offered at population level in rural Malawi. Methods HIV counselling and testing was offered to individuals aged 18–59 at their homes. Individual variables were collected by interviews and physical examinations. Household variables were determined as part of a previous census. Multivariate models allowing for household and community clustering were used to assess associations between HIV test refusal and explanatory variables. Results Of 2303 eligible adults, 2129 were found and 1443 agreed to HIV testing. Test refusal was less likely by those who were never married [adjusted odds ratio (aOR) 0.50 for men (95% CI 0.32; 0.80) and 0.44 (0.21; 0.91) for women] and by farmers [aOR 0.70 (0.52; 0.96) for men and 0.59 (0.40; 0.87) for women]. A 10% increase in cluster refusal rates increased the odds of refusal by 1.48 (1.32; 1.66) in men and 1.68 (1.32; 2.12) in women. Women counsellors increased the odds of refusal by 1.39 (1.00; 1.92) in men. Predictors of HIV test refusal in women were refusal of the husband as head of household [aOR 15.08 (9.39; 24.21)] and living close to the main road [aOR 6.07 (1.76; 20.98)]. Common reasons for refusal were fear of testing positive, previous HIV test, knowledge of HIV serostatus and the need for more time to think. Conclusion Successful VCT strategies need to encourage couples counselling and should involve participation of men and communities. 相似文献
88.
Margaret McGrath Michelle Anne Low Emma Power Annie McCluskey Sandra Lever 《Archives of physical medicine and rehabilitation》2021,102(5):999-1010
ObjectiveTo systematically review health care professionals’ practices and attitudes toward addressing sexuality with people who are living with chronic disease and disability.Data SourcesScopus, PubMed, PsycINFO, Cumulative Index to Nursing and Allied Health, Allied and Complementary Medicine Database, and MEDLINE were searched to August 2020 for English language publications. Reference lists of relevant publications were also searched.Study SelectionEligible studies reported on knowledge, attitudes, and behaviors of health care professionals about addressing sexuality in the context of chronic disease and disability. The search yielded 2492 records; 187 full texts were assessed for eligibility and 114 documents were included (103 unique studies). Study quality was rated using the Mixed Methods Appraisal Tool.Data ExtractionCharacteristics of included studies were recorded independently by 2 authors. Differences were resolved through discussion or by a third author.Data SynthesisA sequential, exploratory mixed studies approach was used for synthesis. Pooled analysis showed that 14.2% (95% CI, 10.6-18.9 [I2=94.8%, P<.001]) of health professionals report routinely asking questions or providing information about sexuality. Professionals reported limited confidence, competence, and/or comfort when initiating conversations about sexuality or responding to patient questions. Sexual rehabilitation typically focused on the effect of disease, disability, and medication on sexual function. Broader dimensions of sexuality were rarely addressed.ConclusionDespite recognizing the value of sexuality to health and well-being, most health professionals regardless of clinical context fail to routinely include assessment of sexuality in their practice. Professionals have limited knowledge and confidence when addressing sexuality and experience significant discomfort when raising this topic with people living with chronic disease and disability. Multicomponent implementation programs are needed to improve health professionals’ knowledge, competence, and comfort when addressing sexuality for people living with chronic disease and disability. 相似文献
89.
The grey zone (GZ; 45–54 CGG repeats in the FMR1 gene) is considered a normal allele; however, several studies have found a high frequency of GZ in movement disordered populations. Here, we describe neurological features of fragile X‐associated tremor/ataxia syndrome (FXTAS) in two carriers of GZ alleles, although FXTAS has been defined as occurring only in premutation carriers (55–200 CGG repeats). Both patients had family members who had premutation and were diagnosed with FXTAS. The presence of relatively high GZ alleles with elevated fragile X mental retardation 1 mRNA (FMR1‐mRNA) combined with a family history of FXTAS that may represent a facilitating genetic background for FXTAS are the factors that led to the presence of FXTAS in these individuals with a GZ allele. Further research into clinical involvement of GZ alleles is recommended and the definition of FXTAS may require revision. 相似文献
90.
Cowie Megan E. Huguet Anna Moore Craig McGrath Patrick J. Rao Sanjay Wozney Lori Kits Olga Stewart Sherry H. 《International journal of mental health and addiction》2021,19(2):579-594
International Journal of Mental Health and Addiction - Behavioral activation (BA) is a well-established treatment for depression, often used as an adjuvant for gambling disorder. Internet-based BA... 相似文献