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991.
Diabetic retinopathy (DR) is a common complication of diabetes mellitus and a leading cause of new-onset vision loss in adults worldwide. Current medical and surgical evidence-based care, including laser photocoagulation, is effective in preserving vision. This care is most effective prior to the onset of ocular or visual symptoms, but many diabetic persons do not receive the recommended annual eye examination for the evaluation of the retina for level of DR. With diabetes incidence and prevalence increasing at epidemic rates and the prediction that 370 million people worldwide will have diabetes by the year 2030, human and fiscal resources will be unable to meet the visual needs with current acute care methods. Appropriate and validated telemedicine programs for DR hold the promise of both enrolling patients into appropriate eye care programs and, more importantly, providing more effective, high-quality diabetes eye care based on current and developing technology.  相似文献   
992.
In some mild haemophilia A patients (discrepant phenotype), coagulation FVIII levels by one-stage assay (FVIII-1st) are more than double those by classical two-stage coagulation assay (FVIII-2st), and may fall within the normal range. Our aim was to assess automated two-stage chromogenic FVIII assays (FVIII-chr) for diagnosis of mild discrepant haemophilia A. Three chromogenic FVIII kits (Biophen, Coamatic and Dade-Behring) were evaluated, using recommended and extended incubation times. Samples were tested from patients with discrepant haemophilia (n = 7) and equivalent mild haemophilia (agreement between FVIII-1st and FVIII-2st, n = 4). For equivalent haemophilia, FVIII-chr were consistent with FVIII-1st and FVIII-2st for all kits at all incubation times. For discrepant haemophilia, using recommended incubation times, mean FVIII-chr using Biophen reagents was 22 IU/dl (range 13-31), with Coamatic 26 (17-34) and with Dade-Behring 41 (33-47), compared with 36 (27-44) for FVIII-1st and 8 (6-9) for FVIII-2st. FVIII-chr decreased as incubation time was increased with Biophen and Coamatic, but decreased less with Dade-Behring. FVIII-chr using the Dade-Behring kit gave similar results to FVIII-1st and is not suitable for diagnosis of mild discrepant haemophilia A. FVIII-chr by Biophen and Coamatic kits is suitable for diagnosis of these patients, especially with an extended incubation time.  相似文献   
993.
BACKGROUND: Interventional techniques are commonly performed with adjunctive therapy including clopidogrel, ticlopidine, abciximab and heparin. We wished to assess the current British use of antiplatelet and anticoagulant agents as adjunctive therapies in interventional cardiology in the light of the available evidence base regarding their usage. METHODS: A simple structured questionnaire was sent between August and October 1999 to all interventional cardiology consultants working in the UK regarding their usage of abciximab (ReoPro), heparin, clopidogrel (Plavix) and ticlopidine (Ticlid) peri-procedurally. RESULTS: 68% of consultants responded over the next 4 months, with many replying jointly for a centre rather than individually. Average abciximab use was 8.3% of interventional cases. Eighty-two percent of clinicians used clopidogrel in stented patients. Exact dosages varied considerably. Fifty-three percent of clinicians gave 10000 IU or more of heparin routinely. CONCLUSIONS: These figures are not in line with the published evidence and British interventionists appear to have adopted various strategies to target the use of these agents. In particular, abciximab appears to be being administered reactively, as and when problems arise in the catheterisation lab.  相似文献   
994.
Reimbursement for limited echocardiograms focusing on known pathology rather than complete studies has recently received widespread attention. Few data are available to determine if these limited examinations provide enough information to adequately evaluate many forms of congenital heart disease. Stenosis of normally connecting pulmonary veins is a congenital or acquired cardiac anomaly that is difficult to diagnose clinically and may be detectable only by echocardiography. To evaluate the yield of complete versus limited echocardiograms for detecting the presence and development of stenosis in pulmonary veins with anatomically normal connections, the cardiology database was searched for all patients with this diagnosis presenting between June 1990 and January 2000. Charts were reviewed for demographic data, associated defects, surgeries, and outcomes. Angiograms and echocardiograms were reviewed for location and severity of pulmonary vein stenosis. A pulsed-wave Doppler signal of > 1.6 mm/sec with loss of phasic flow was used to define stenosis. Eighteen patients were identified and ranged in age at first evaluation from 1 day to 17 years (median 15 days). All 18 patients had associated cardiac anomalies, and 4 (22%) of 18 had Trisomy 21. Pulmonary vein stenosis was detected on the initial evaluation in 5 patients, detected 8 +/- 5 months after the initial echocardiogram in 11 patients, and missed by echocardiography in 2 patients who were diagnosed by cardiac catheterization. The initial echocardiograms were complete, with pulsed-Doppler sampling of all four pulmonary veins in 17 of 18 patients. Of the 12 patients who had echocardiographic evidence of late stenosis, 10 had 17 limited interim studies prior to eventually having a complete diagnostic follow-up study. Of the two patients in whom the diagnosis was missed by echocardiography, one initial study was technically inadequate (17-year-old) and one had only limited interim studies after the initial echocardiogram. Of the 9 patients in whom repair of the pulmonary vein stenosis was attempted, 3 had no residual obstruction and 6 had progressive stenosis (three deaths). Of the remaining nine patients who had no intervention for their pulmonary venous stenosis, four have died from progressive pulmonary hypertension. Stenosis of normally connecting pulmonary veins is an uncommon lesion that has a significant impact on clinical outcome. The stenoses might be undetectable on limited echocardiograms that focus on evaluating only specified pathology. Complete follow-up examinations might be warranted to diagnose this lesion. This may be an important consideration when formulating reimbursement policies.  相似文献   
995.
In an attempt to decrease the relapse rate after bone marrow transplantation (BMT) for advanced acute leukemia, we initiated studies using 131I-labeled anti-CD45 antibody (BC8) to deliver radiation specifically to hematopoietic tissues, followed by a standard transplant preparative regimen. Biodistribution studies were performed in 23 patients using 0.5 mg/kg trace 131I-labeled BC8 antibody. The BC8 antibody was cleared rapidly from plasma with an initial disappearance half-time of 1.5 +/- 0.2 hours, presumably reflecting rapid antigen- specific binding. The mean radiation absorbed doses (cGy/mCi131I administered) were as follows: marrow, 7.1 +/- 0.8; spleen, 10.8 +/- 1.4; liver, 2.7 +/- 0.2; lungs, 2.1 +/- 0.1; kidneys, 0.7 +/- 0.1; and total body, 0.4 +/- 0.03. Patients with acute myelogenous leukemia (AML) in relapse had a higher marrow dose (11.4 cGy/mCi) than those in remission (5.2 cGy/mCi; P = .001) because of higher uptake and longer retention of radionuclide in marrow. Twenty patients were treated with a dose of 131I estimated to deliver 3.5 Gy (level 1) to 7 Gy (level 3) to liver, with marrow doses of 4 to 30 Gy and spleen doses of 7 to 60 Gy, followed by 120 mg/kg cyclophosphamide (CY) and 12 Gy total body irradiation (TBI). Nine of 13 patients with AML or refractory anemia with excess blasts (RAEB) and two of seven with acute lymphocytic leukemia (ALL) are alive disease-free at 8 to 41 months (median, 17 months) after BMT. Toxicity has not been measurably greater than that of CY/TBI alone, and the maximum tolerated dose has not been reached. This study demonstrates that with the use of 131I-BC8 substantially greater doses of radiation can be delivered to hematopoietic tissues as compared with liver, lung, or kidney, which may improve the efficacy of marrow transplantation.  相似文献   
996.
The purpose of this report was to evaluate scintigraphy analysis of Southern blot hybridization as a method to quantify the breakpoint cluster region (BCR) rearrangement of Philadelphia chromosome (Ph)+ chronic myelogenous leukemia (CML). Cytogenetic and molecular studies performed simultaneously on 474 bone marrow and/or blood samples from 300 patients treated with alpha-interferon-based therapy were compared. Molecular results were expressed as the percentage of rearranged BCR bands versus the total scintigraphic signal. The percentage of Ph+ metaphases was calculated on 25 metaphases. The results of molecular studies obtained on both peripheral blood and bone marrow samples were identical. The rank correlation between the BCR quantification and the percentage of Ph positivity in 465 samples was excellent (r = .78). However, of 99 samples with a normal karyotype, 24% had a BCR rearrangement. Of 86 samples with no BCR rearrangement, 13% showed a Ph chromosome. Of 49 samples with partial cytogenetic remission (Ph+ metaphases, 1% to 34%), 23% had no BCR rearrangement. In samples with a minor or no cytogenetic response (Ph+ metaphases, > 34%), BCR analysis overestimated the degree of response in 73 of 326 samples (22%). Nevertheless, survival analysis by BCR quantification level showed statistically better outcome for patients in complete or partial molecular response (P < .01). Molecular quantification of BCR was useful in monitoring the course of Ph+ CML. This method, which can be used on peripheral blood, detected residual disease not shown by cytogenetic analysis and was prognostically relevant as a measure of disease suppression.  相似文献   
997.
998.
Normally nonmetastatic murine sis-transformed BALB/c 3T3 cells, transfected with human CD44s gene (hCD44s), acquire spontaneous metastatic capacity to the lung. The mechanism(s) of this facilitated micrometastasis was analyzed in an experimental metastasis model. Human CD44s overexpression promoted the earliest stages severalfold (initial implantation and subsequent stabilization of tumor cells) but was irrelevant for later stages (subsequent outgrowth) of lung experimental micrometastasis. By injecting mixed populations of parental (nonmetastatic) and CD44s-transfected cells, it was shown that cell–cell adhesion between tumor and parental cells was not promoted by hCD44s but that promotion of cell–cell adhesion to lung endothelium or specifically between transfected cells (via hyaluronan) are likely mechanisms. Results obtained with hCD44s-negative primary tumor cells and hCD44s-positive or -negative variants of lung micrometastatic cells (after s.c. injection of transfectants) confirmed the importance of CD44s overexpression for early but not late stages of experimental lung metastasis. Therefore, CD44s represents a metastasis-facilitating molecule that is irrelevant for primary tumor outgrowth but that promotes micrometastasis to the lungs at the very earliest stages.  相似文献   
999.
OBJECTIVE: Many patients fail to attend cardiac rehabilitation. Attempts to identify sociodemographic or clinical predictors of non-attendance have not been very successful; therfore, this study aimed to determine whether the illness beliefs held during hospitalisation by patients who had suffered acute myocardial infarction or who had undergone coronary artery bypass graft surgery could predict cardiac rehabilitation attendance. SUBJECTS AND METHODS: 152 patients were prospectively studied of whom 41% had attended cardiac rehabilitation at six months. RESULTS: In addition to being older, less aware of their cholesterol values, and less likely to be employed, non-attenders were less likely to believe their condition was controllable and that their lifestyle may have contributed to their illness. CONCLUSION: It should now be determined whether interventions aimed at optimising certain perceptions could promote cardiac rehabilitation uptake among those patients who could benefit the most.  相似文献   
1000.
G V Childs  G Unabia  R Tibolt  J M Lloyd 《Endocrinology》1987,121(5):1801-1813
Gonadotropes from cycling female rats were studied to investigate possible mechanisms for the nonparallel release of LH and FSH. The percentages of total gonadotropes increased from 14% during estrus (E) to 18% by diestrous day 2. More of these cells became multihormonal on the morning of proestrus (P; from 46% during diestrus to 69%). Since LH-containing cells increased from 7% at E to 13.3% during early proestrus, this suggests that monohormonal FSH cells may have contributed by synthesizing LH. Gonadotrope cell areas were greatest just before the LH surge (P 1600 h). Microdensitometric measurements demonstrated that the amount and density of immunoperoxidase stain for either gonadotropin subunit were highest during the midafternoon of P. Interestingly, the amount of stain for LH continued to increase during the LH surge, suggesting that the stain had detected newly synthesized LH beta. At the same time, the average density of the LH beta stain decreased. In contrast, the amount, concentration, and density of stain for FSH beta increased during the afternoon of P and decreased during late P and early E. The percentages of granules that contained immunogold stains for only LH or FSH (monohormonal granules) at P 1600-P 1700 h were 3-4 times higher than those in diestrous rats. The percentages of monohormonal LH granules declined during the proestrous surge, whereas percentages of monohormonal FSH granules declined during the first rise (P 1900 h) and after the second rise in serum FSH (E 0800 h). Finally, the average number of gold particles per micron 2 granule area rose over the value in diestrous rats during P 1600-P 1700 h. These studies suggest that multihormonal gonadotropes support nonparallel gonadotropin release by changing the rate of subunit packaging and transit in the Golgi complex.  相似文献   
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