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991.
The mission of the Veterans Health Administration's (VHA) quality enhancement research initiative (QUERI) is to enhance the quality of VHA health care by implementing clinical research findings into routine care. This paper presents lessons that QUERI investigators have learned through their initial attempts to pursue the QUERI mission. The lessons in this paper represent those that were common across multiple QUERI projects and were mutually agreed on as having substantial impact on the success of implementation. While the lessons are consistent with commonly recognized ingredients of successful implementation efforts, the examples highlight the fact that, even with a thorough knowledge of the literature and thoughtful planning, unexpected circumstances arise during implementation efforts that require flexibility and adaptability. The findings stress the importance of utilizing formative evaluation techniques to identify barriers to successful implementation and strategies to address these barriers.  相似文献   
992.
Pseudo-obstruction syndromes   总被引:1,自引:0,他引:1  
Chronic intestinal pseudo-obstruction (CIP) is a clinical syndrome characterized by symptoms and signs of intestinal occlusion, in absence of any mechanical obstruction of the gut lumen. It causes impaired transit of intestinal contents and is determined by abnormalities of motor activity. The term CIP is used to indicate a heterogeneous group of disorders with many different pathogenic mechanisms. The defect in the regulation of intestinal transit can be at any level of motility control. Two main types of CIP are recognized, termed respectively myogenic (when smooth muscle cells are affected) and neurogenic (caused by abnormalities of extrinsic and/or intrinsic nervous supplies). Both types may be secondary to a variety of recognizable diseases or idiopathic. In myogenic CIP, intestinal transit is impaired because of lack of propulsive strength; in the neurogenic form, contractions are powerful but not sufficiently co-ordinated to propel intestinal contents aborally in an organized fashion. CIP belongs to the large and loosely defined group of digestive functional disorders. These disorders probably share common pathogenic mechanisms but with different expressiveness. The reasons why only some patients present recurrent symptomatological bouts resembling mechanical occlusion has not been clarified. This aspect is of great clinical relevance and deserves attention, as CIP patients, unlike other patients with severe functional disorders, may undergo repeated, useless and potentially dangerous operations. The diagnosis of CIP may be suggested by clinical features and is based on radiological, endoscopic, manometric, and histological findings. Recent technological improvements facilitate the recognition of this intriguing syndrome. In particular, manometric recording of the small bowel motility, which has long been considered an important research technique, can now also be regarded as a useful diagnostic tool.  相似文献   
993.
In Crohn's disease, prednisone is believed to be ineffective for relapse prevention. Because all patients with Crohn's Disease Activity Index lower than 150 and with some altered lab tests (erythrocyte sedimentation rate, C-reactive protein, alpha-1-acid glycoprotein, alpha-1-acid antitrypsin, and white blood cell count) had a clinical relapse in 18 months of follow-up, we tried to ascertain whether methylprednisolone could reduce the risk of clinical relapse in such patients. Eighteen patients were included in a controlled study against placebo. Nine patients were treated with methylprednisolone at a dosage of 0.25 mg/kg daily for a period of 6 months; treatment was discontinued if disease relapsed or if lab tests were normalized. During the steroid treatment, 1 of 9 patients showed a clinical relapse; in 7, the normalization of lab tests was obtained; in 5 of these 7 patients a relapse occurred within 1 month after the suspension of the treatment; in 1 patient, lab tests remained altered. In those 9 patients on placebo, relapses occurred in 7. We conclude that methylprednisolone was effective in the prevention of relapses for patients in clinical remission but with altered lab tests.  相似文献   
994.
A multicentre study involving 9 Italian institutions was carried out to compare the efficacy and safety of ranitidine 150 mg b.i.d. and ranitidine 300 mg nocte in the treatment of reflux oesophagitis. 117 patients with histologically proven oesophagitis were randomly allocated to two comparable treatment groups. Efficacy and reliability were evaluated by clinical and laboratory tests at the beginning of the study, and at 3 and 6 weeks; endoscopy and biopsies were performed at the beginning and at 6 weeks. Treatment with ranitidine for 6 weeks led to total disappearance of gastro-oesophageal reflux symptoms in 60% of patients, with percentages of partial improvement varying between 85% and 95% of cases. Improvement in the results of endoscopic examination was 85%, of which 55% were cured. Microscopic examination revealed an improvement of 36% and 44%, with a cure rate of 18% and 26% respectively. With regard neither to the regression of symptoms nor to the macroscopic and microscopic inflammation of the oesophageal mucosa did statistical examination show significant differences in the therapeutic efficacy of ranitidine 150 mg b.i.d. or 300 mg nocte for treatment of reflux oesophagitis.  相似文献   
995.
Recipients of renal transplants have an increased risk of developing secondary malignancies. About 4% of patients who underwent kidney transplantation will develop cancer, and 1% of transplanted patients will develop lymphoproliferative disorders. According to clinical analyses and laboratory data, the main reason for increased risk of developing malignant disease in this group of patients, is their immunocompromised status due to immunosuppressive treatment. So called "strong" immunosuppressive drugs like antilymphocytic globulin (ALG), antithymocytic globulin (ATG), or monoclonal globulin OKT3 seem to favor the development of secondary malignancies much more than other drugs, like: corticosteroids, azathioprine (AZA), or cyclosporine (CsA). Secondary lymphoproliferative disorders are usually connected with reactivation of Ebstein-Barr virus infection. Patients with early onset (<1 year after the transplantation) have a favorable clinical course after withdrawal of immunosuppression. The subset of late-onset (>1 year) has usually much more aggressive clinical course and patients require intensive treatment. The general recommendation in these patients is to stop or to reduce the immunosuppressive treatment and to continue the chemotherapy in full dose. This treatment is often complicated by severe infections, but it offers a chance to achieve remission without worsening the function of transplanted organ. In this paper we are presenting five patients with secondary lympho- or myeloproliferative disorders after kidney transplantation and give an overview of the recent literature in this field.  相似文献   
996.
Low birth weight is a risk factor for the subsequent development of hypertension in humans. We previously reported that reduced uterine perfusion in the pregnant rat results in growth-restricted offspring predisposed to the development of hypertension. The purpose of this study was to determine whether the sympathetic nervous system plays a role in mediating hypertension in this model of low birth weight. Weight at birth was significantly decreased in male growth-restricted offspring (5.9+/-0.1 grams) as compared with male control offspring (6.5+/-0.2 grams; P<0.05). At 10 weeks of age, growth-restricted offspring and control offspring were randomly assigned to either an intact group (sham-denervated) or a group subjected to bilateral renal denervation. For sham-denervated offspring, mean arterial pressure was significantly elevated in growth-restricted offspring (145+/-4 mm Hg; n=7) as compared with control offspring (134+/-3 mm Hg; P<0.05; n=9) at 12 weeks of age. Bilateral renal denervation resulted in a marked reduction in arterial pressure in growth-restricted offspring (125+/-3 mm Hg; P<0.01; difference of 20 mm Hg versus sham growth-restricted; n=8) but no significant decrease in control offspring (127+/-3 mm Hg; difference of 7 mm Hg versus sham control; n=9). Adequacy of renal denervation was verified by >90% reduction in renal norepinephrine content. Therefore, these findings indicate the renal nerves play an important role in mediating hypertension in adult growth-restricted offspring.  相似文献   
997.
BACKGROUND AND OBJECTIVES: The aim of this study was to demonstrate the efficiency of diverting the initial 20-ml donation from the collection bag and of an improved donor-arm disinfection procedure in reducing bacterial contamination in blood. MATERIALS AND METHODS: Donations were collected in bags specially manufactured for the study. These bags incorporated two satellite pouches into each of which 20 ml of blood was collected. Blood initially flowed into sample pouch P1, representing a diversion pouch. Pouch P2 was then filled with 20 ml of blood, which allowed us to sample the collection bag after diversion was complete. Blood then flowed into the standard collection bag. The contents of the pouches were aerobically and anaerobically cultured on the BacT/ALERT automated culture system for 7 days. Two procedures were investigated in the study (each involving 1409 blood donations): one analysed the current disinfection procedure; and the other analysed an improved donor-arm disinfection procedure. RESULTS: The use of diversion alone resulted in a 47% reduction in contamination, and improved donor-arm disinfection alone resulted in a 57% reduction in contamination. Diversion plus improved donor-arm disinfection produced a predicted 77% reduction in contamination. CONCLUSIONS: The study validates diversion and an improved donor-arm disinfection procedure. In combination, these two interventions produced a substantial reduction in contamination. These procedures are to be introduced by the English National Blood Service to enhance the safety of the blood supply.  相似文献   
998.
Recent studies showed that such retinal vascular signs as quantitative retinal vascular caliber were associated with increased risk of incident coronary heart disease (CHD), but whether these retinal vascular signs add to the prediction of CHD over and above traditional CHD risk factors was not addressed. Whether these signs add to the prediction of CHD over and above the Framingham risk score in people (n = 9,155) without diabetes selected from the ARIC Study was investigated. Incident CHD was ascertained using standardized methods, and retinal vascular caliber and other retinal signs were measured from retinal photographs. After a mean of 8.8 years of follow-up, there were 700 incident CHD events. Women with wider retinal venular caliber (hazard ratio 1.27/1-SD increase, 95% confidence interval 1.08 to 1.50) and narrower retinal arteriolar caliber (hazard ratio 1.31/1-SD decrease, 95% confidence interval 1.10 to 1.56) had a higher risk of incident CHD after adjusting for Framingham risk score variables. Area under the receiver operator characteristic curve increased from 0.695 to 0.706 (1.7% increase) with the addition of retinal vascular caliber to the Framingham risk model. Risk prediction models with and without retinal vascular caliber both fitted the data and were well calibrated for women. In men, retinal vascular caliber was not associated with CHD risk after adjustment. Other retinal vascular signs were not associated with 10-year incident CHD in men or women. In conclusion, although retinal vascular caliber independently predicted CHD risk in women, the incremental predictive ability over that of the Framingham model was modest and unlikely to translate meaningfully into clinical practice.  相似文献   
999.
Thrombophilia, the state of increased tendency for blood clotting, is considered the disorder of a complex etiology, caused by both environmental and genetic factors. As gene variants predisposing to thrombophilia and influencing the increased risk of vein thrombosis might influence response to local thrombolysis, the aim of the work was to characterize the pharmacogenetic conditions for local streptokinase treatment in patients with a deep vein thrombosis (DVT) of lower extremities based on the following polymorphism analyses: G1691A polymorphism of factor V (FV), G20210A polymorphism of prothrombin (PT), A4250G (Thr312Ala) polymorphism of fibrinogen-alpha (FGA), G(-455)A polymorphism of fibrinogen-beta (FGB), 4G/5G polymorphism of plasminogen activator inhibitor type 1(PAI-1) and insertion/deletion (I/D) polymorphism of tissue plasminogen activator (t-PA). The study included 40 DVT patients who underwent a local thrombolytic treatment within 14-day period from diagnosis. Full recanalization was achieved in 20 subjects (50%) [group R(+)], whereas incomplete or total lack of recanalization was identified in the remaining 20 patients [group R(-)]. No major complications of thrombolytic treatment occurred in the studied group. In the case of prothrombin gene all individuals carried homozygous wild type genotype (GG). Prevalence of the genotypes and alleles of the remaining five polymorphisms did not differ significantly between the groups R(+) and R(-). Neither sex nor age, smoking or time period from diagnosis to introduction of the thrombolytic treatment significantly influenced treatment efficacy. The results of the study suggest that a local thrombolysis with streptokinase introduced within two week period from the diagnosis is a safe and efficient method of treatment for deep vein thrombosis of lower extremities. However, size of the group is insufficient to clearly determine the association between investigated polymorphisms and efficacy of local treatment with streptokinase.  相似文献   
1000.
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