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81.
82.
Detectability of breast cancer with magnetic resonance (MR) imaging versus xeromammography was quantitatively compared. MR images were obtained of breasts of 120 women who underwent xeromammography. T1 values were determined for masses larger than 2 cm. Cancer was histologically confirmed in 39 breasts and was considered excluded from 81 due to results of biopsy, cyst aspiration, or sonography or absence of change in xeromammographic findings over time. Images were blindly interpreted by three observers, and results were expressed as receiver operating characteristic curves. Detectability of breast cancer was substantially better with xeromammography than with MR imaging for all observers (P less than .03, 10(-6), and .001). On MR images, spiculation of a mass, distorted architecture, skin thickening, and nipple or skin retraction were specific but relatively insensitive indicators of cancer. Masses with smooth, distinct margins and signal intensity greater than that of fat on T2-weighted images were always benign. Other findings and T1 values were not diagnostically useful. The authors conclude that xeromammography is superior to MR imaging in detection of breast cancer.  相似文献   
83.

Background  

Relatively little is known about the incidence of prescribing errors and there has been no work on this in a single specialty ophthalmic hospital. Knowing where and when errors are most likely to occur is generally felt to be the first step in trying to prevent these errors. This study is an attempt in, the setting of an eye hospital, to try to identify and attribute these medication errors.  相似文献   
84.
长期以来,一直存在抗高血压药物是否有致癌作用的争议.自从在年龄>50岁的妇女中使用萝芙碱提取物造成乳腺癌发病率增加的报道后[1],这一争议已持续了30年.Sipahi和同事们最近的研究显示:血管紧张素受体拮抗剂(angiotensin receptor-blockers,ARB)有较高的致癌风险.这一发现再次引发了抗...  相似文献   
85.
86.
Screening blood donations for human T-lymphotropic virus types I and II (HTLV-I/II) continues to be important in protecting the safety of blood products and controlling the global spread of these retroviruses. We have developed a fully automated, third generation chemiluminescent immunoassay, ARCHITECT rHTLV-I/II, for detection of antibodies to HTLV-I/II. The assay utilizes recombinant proteins and synthetic peptides and is configured in a double antigen sandwich assay format. Specificity of the assay was 99.98% (9,254/9,256, 95% CI = 99.92-100%) with the negative specimens from the general population including blood donors, hospital patients and pregnant women from the US, Japan and Nicaragua. The assay demonstrated 100% sensitivity by detecting 498 specimens from individuals infected with HTLV-I (n = 385) and HTLV-II (n = 113). ARCHITECT rHTLV-I/II results were in complete agreement with the Murex HTLV-I/II reference assay and 99.7% agreement with the Genelabs HTLV Blot 2.4 confirmatory assay. Analytical sensitivity of the assay was equivalent to Murex HTLV-I/II assay based on end point dilutions. Furthermore, using a panel of 397 specimens from Japan, the ARCHITECT rHTLV-I/II assay exhibited distinct discrimination between the antibody negative (Delta Value = -7.6) and positive (Delta Value = 7.6) populations. Based on the excellent specificity and sensitivity, the new ARCHITECT rHTLV-I/II assay should be an effective test for the diagnosis of HTLV-I/II infection and also for blood donor screening.  相似文献   
87.
Lee  SB; Rao  AK; Lee  KH; Yang  X; Bae  YS; Rhee  SG 《Blood》1996,88(5):1684-1691
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function.  相似文献   
88.
Red cell alloimmunization in multitransfused HLA-typed patients   总被引:1,自引:0,他引:1  
The authors studied retrospectively the formation of clinically significant red cell (RBC) alloantibodies in 958 HLA-typed, multiply transfused patients receiving kidney (603 patients) or liver (263 patients) transplants or plateletpheresis transfusions (92 patients). RBC alloantibodies were found in 91 (9.5%) of these patients and multiple antibodies in 35 (3.7%). Rh (D, C, c, and E) antibodies accounted for 49 percent of the total and Kell antibodies for 31 percent. Antibodies were found in 15 percent of apheresis recipients and in 8.6 percent of renal and 9.5 percent of liver transplantation patients. No association was found between any HLA-A, HLA-B, or HLA-DR phenotype and the presence of RBC alloantibodies, either in general or when analyzed according to the specific antibody. Renal transplant patients with RBC alloantibodies were somewhat more broadly HLA-alloimmunized than were those without RBC alloantibodies. Patient gender did not affect these results. The authors concluded that the immune response to RBC alloantigens is independent of HLA type but is associated with an increased level of HLA antibody formation.  相似文献   
89.
AIM: To determine the prevalence of bipolar disorder (BD) and sub-threshold symptoms in children with attention deficit hyperactivity disorder (ADHD) through 14 years’ follow-up, when participants were between 21-24 years old.METHODS: First, we examined rates of BD type I and II diagnoses in youth participating in the NIMH-funded Multimodal Treatment Study of ADHD (MTA). We used the diagnostic interview schedule for children (DISC), administered to both parents (DISC-P) and youth (DISCY). We compared the MTA study subjects with ADHD (n = 579) to a local normative comparison group (LNCG, n = 289) at 4 different assessment points: 6, 8, 12, and 14 years of follow-ups. To evaluate the bipolar variants, we compared total symptom counts (TSC) of DSM manic and hypomanic symptoms that were generated by DISC in ADHD and LNCG subjects. Then we sub-divided the TSC into pathognomonic manic (PM) and non-specific manic (NSM) symptoms. We compared the PM and NSM in ADHD and LNCG at each assessment point and over time. We also evaluated the irritability as category A2 manic symptom in both groups and over time. Finally, we studied the irritability symptom in correlation with PM and NSM in ADHD and LNCG subjects.RESULTS: DISC-generated BD diagnosis did not differ significantly in rates between ADHD (1.89%) and LNCG 1.38%). Interestingly, no participant met BD diagnosis more than once in the 4 assessment points in 14 years. However, on the symptom level, ADHD subjects reported significantly higher mean TSC scores: ADHD 3.0; LNCG 1.7; P < 0.001. ADHD status was associated with higher mean NSM: ADHD 2.0 vs LNCG 1.1; P < 0.0001. Also, ADHD subjects had higher PM symptoms than LNCG, with PM means over all time points of 1.3 ADHD; 0.9 LNCG; P = 0.0001. Examining both NSM and PM, ADHD status associated with greater NSM than PM. However, Over 14 years, the NSM symptoms declined and changed to PM over time (df 3, 2523; F = 20.1; P < 0.0001). Finally, Irritability (BD DSM criterion-A2) rates were significantly higher in ADHD than LNCG (χ2 = 122.2, P < 0.0001), but irritability was associated more strongly with NSM than PM (df 3, 2538; F = 43.2; P < 0.0001).CONCLUSION: Individuals with ADHD do not appear to be at significantly greater risk for developing BD, but do show higher rates of BD symptoms, especially NSM. The greater linkage of irritability to NSM than to PM suggests caution when making BD diagnoses based on irritability alone as one of 2 (A-level) symptoms for BD diagnosis, particularly in view of its frequent presentation with other psychopathologies.  相似文献   
90.
Sera from rhesus monkeys maintained at three separate geographic regions were found to possess naturally occurring antibody to the Mason-Pfizer monkey virus (MPMV) major structural protein. The specificity of this reactivity was established by absorption with purified viral protein. While animals from two of these colonies were housed in association with MPMV-infected monkeys, no such prior exposure to virus-infected animals could be traced in the case of the third colony. These results in combination with the previous inability to detect full complements of MPMV genetic sequences in the cellular DNA of the normal rhesus monkeys provide evidence for horizontal transmission of MPMV. Alternatively, the present findings could reflect humoral immune response to expression of an endogenous type D retrovirus highly related to MPMV.  相似文献   
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