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991.
Scimitar syndrome: four new cases examined with CT   总被引:3,自引:0,他引:3  
Godwin  JD; Tarver  RD 《Radiology》1986,159(1):15-20
Four new cases of scimitar syndrome illustrate the complex derangement of the right lung architecture. Computed tomography (CT) helped in demonstrating the hyparterial relationship of the right bronchus to the pulmonary artery, the course and termination of the scimitar vein, the mediastinal shift, unusual fissures, and abnormal lobation and bronchial distribution. The CT findings confirm that the retrosternal opacity and indistinct right heart border are results of the mediastinal shift. One case had features resembling, but clearly distinguishable from, the horseshoe lung syndrome.  相似文献   
992.
993.
Psychotic patients' understanding of informed consent   总被引:2,自引:0,他引:2  
Courts have found psychiatric patients to have the qualified right to refuse treatment. Particularly problematic is whether newly admitted psychiatric patients can comprehend information and give informed consent. The authors examined the ability of voluntary and involuntary psychotic patients to understand information about antipsychotic medication, related this assessment to psychopathology, and evaluated factors involved in hypothetical acceptance or refusal of treatment. Although most patients stated they had understood informed consent material, objective ratings did not support this. Impaired understanding was significantly associated with thought disturbance but did not affect hypothetical acceptance or refusal of antipsychotics. Legal status was not a significant factor.  相似文献   
994.
995.
Natural history of intrahepatic canine islet cell autografts.   总被引:8,自引:2,他引:6       下载免费PDF全文
We have serially followed the function of intrahepatic canine islet autografts in 15 beagle dogs for up to 24 mo. Of these, only 20% sustained normal levels of fasting blood glucose for greater than 15 mo posttransplant. Failure of autograft function was accompanied by a preferential loss of well-granulated beta cells in the engrafted islets. The chronic stimulation of an initially marginal intrahepatic beta-cell mass ultimately resulted in metabolic deterioration and loss of beta cells below the minimal threshold required to maintain normal fasting blood glucose levels. It is possible that transplantation of a larger mass of islets would result in indefinite graft function in dogs. However, it remains to be demonstrated in larger mammals, including humans, whether an islet cell mass that is initially adequate in a heterotropic site such as the liver can remain functionally competent over a prolonged period.  相似文献   
996.
Limitations of Polybrene to Detect ABO Incompatibility   总被引:2,自引:0,他引:2  
The ability of the manual Polybrene test to detect ABO incompatibility was assessed since the anti-human globulin phase of the crossmatch is no longer mandated under many circumstances by the Standards of the American Association of Blood Banks, while the ability of the crossmatch to detect ABO incompatibility remains a requirement. 10,084 randomly selected patient samples (from approximately 6,000 different patients) were entered into a double-blind study. Sera from 97 different patients gave unexpectedly negative reactions with A2 and/or B cells in the manual Polybrene test. 94 of these sera reacted as expected in saline (87 after an immediate-spin examination). The manual Polybrene test does not provide adequate assurance of ABO compatibility.  相似文献   
997.
Alcohol increases cigarette smoking: a laboratory demonstration   总被引:4,自引:0,他引:4  
Most people would agree that a relationship exists between drinking alcohol and smoking cigarettes, but there is very little empirical evidence demonstrating a direct causal association. Study of the relationship has been hampered by the lack of a simple laboratory methodology. This article describes an efficient experimental paradigm. Fourteen male narcotic addicts in methadone maintenance treatment volunteered to come to the laboratory for two smoking sessions, during which each subject was given either an alcoholic drink or orange juice, followed by three cigarettes at 20-minute intervals. Drinking alcohol significantly increased the amount and rate of smoking. However, not all subjects reacted to alcohol with increased smoking, and we were unable to account for those individual differences. Our finding supports the theory that a direct causal mechanism linking smoking and drinking exists. That link probably has clinical significance, because there is evidence that ex-smokers are at particularly high risk when they drink alcohol.  相似文献   
998.
Suprasellar lesions: evaluation with MR imaging   总被引:2,自引:0,他引:2  
Karnaze  MG; Sartor  K; Winthrop  JD; Gado  MH; Hodges  FJ  d 《Radiology》1986,161(1):77-82
The authors retrospectively evaluated the characteristics on magnetic resonance (MR) images of 59 suprasellar lesions and compared them with computed tomography (CT) scans in 55 of the cases in which CT was performed. A diverse number of lesions were included: 17 pituitary adenomas; eight optic or hypothalamic gliomas; six craniopharyngiomas; six vascular anomalies; four lesions with extension into the suprasellar space; three metastases; two each of meningioma, hamartoma, germinoma, sarcoid granuloma, and teratoma; and one each of lymphoma, optic tract hematoma, cerebrospinal fluid-borne metastasis, pituitary hyperplasia, and sphenoid sinus mucocele. MR enabled characterization of lesions containing hemorrhage, fat, flowing blood, mucus, and cyst and allowed more specific diagnoses than CT in 6% of cases. MR was equivalent to CT in allowing lesions to be detected and in 20% of cases more accurately defined altered perisellar anatomy. Vascular abnormalities can be better evaluated with MR, and use of angiography can be avoided in some cases.  相似文献   
999.
One hundred consecutive female patients with active systemic lupus erythematosus (SLE) were studied from the cardiovascular point of view by means of non invasive methods. Seventy percent of the cases presented some type of cardiovascular anomaly. Seventy four percent of the resting electrocardiograms were abnormal as well as 72% of the M mode echocardiograms and 55% of the cardiac X ray series. The most frequent observed complications were: pericarditis and or pericardial effusion (39%), arterial hypertension (22%), ischemic heart disease (16%), myocarditis (14%), congestive heart failure (10%), pulmonary hypertension (9%), valvular heart disease (9%), pleural effusion (7%) and cerebro vascular accident (3%). We analyzed each one of these complications and found of special interest the high incidence of ischemic heart disease which is more frequent than has been hitherto reported. Ischemic heart disease was observed in two types of patients: a) Those with long term steroid therapy. In these, the mechanism seems to be an atherosclerotic disease probably induced by the chronic use of steroids. The management of these cases do not differ from other types of coronary heart disease due to atherosclerosis. b) Those with frank episodes of vasculitis in whom the basic mechanism is an inflammatory process of the coronary arteries and its treatment is fundamentally that of the vasculitis. We consider necessary to study routinely all patients with SLE through non invasive cardiological methods.  相似文献   
1000.
Patient navigators—individuals who assist patients through the healthcare system to improve access to and understanding of their health and healthcare—are increasingly used for underserved individuals at risk for or with cancer. Navigation programs can improve access, but it is unclear whether they improve the efficiency and efficacy of cancer diagnostic and therapeutic services at a reasonable cost, such that they would be considered cost‐effective. In the current study, the authors outline a conceptual model for evaluating the cost‐effectiveness of cancer navigation programs. They describe how this model is being applied to the Patient Navigation Research Program, a multicenter study supported by the National Cancer Institute's Center to Reduce Cancer Health Disparities. The Patient Navigation Research Program is testing navigation interventions that aim to reduce time to delivery of quality cancer care (noncancer resolution or cancer diagnosis and treatment) after identification of a screening abnormality. Examples of challenges to evaluating cost‐effectiveness of navigation programs include the heterogeneity of navigation programs, the sometimes distant relation between navigation programs and outcome of interest (eg, improving access to prompt diagnostic resolution and life‐years gained), and accounting for factors in underserved populations that may influence both access to services and outcomes. In this article, the authors discuss several strategies for addressing these barriers. Evaluating the costs and impact of navigation will require some novel methods, but will be critical in recommendations concerning dissemination of navigation programs. Cancer 2009. © 2009 American Cancer Society.  相似文献   
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