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71.
Evaluation of atypical human immunodeficiency virus immunoblot reactivity in blood donors 总被引:6,自引:0,他引:6
NL Dock ; HV Lamberson Jr ; TA O''Brien ; DE Tribe ; SS Alexander ; BJ Poiesz 《Transfusion》1988,28(5):412-418
Blood donors reactive by enzyme-linked immunosorbent assay for antibody to the human immunodeficiency virus (HIV) who showed atypical patterns of viral core protein reactivity on Western blot were monitored for several months. Characterization of their antibodies was performed by 1) use of recombinant HIV proteins; 2) determination of cross-reactivity to HTLV-I, HTLV-II, and HTLV-IV: 3) assessment of immune status; and 4) identification of potentially interfering autoantibodies. Nineteen of 20 donors maintained the same HIV antibody reactivity throughout the follow-up period; the other donor became fully antibody-positive. Eighteen of 20 donors' sera showed clear reactivity with HIV recombinant core proteins. Ten of 19 donor samples demonstrated cross-reactivity to HTLV-IV; 3 of these 10 also cross-reacted with HTLV-I. The immune status of all donors was normal, although the medical histories and HLA antibody screens suggested possible autoimmune reactivity in 9 of 18 donors. During follow-up interviews, three donors reported possible risk factors for HIV infection that had not been acknowledged at the time of blood donation. We conclude that exclusion of donors with these atypical serologic test results is warranted while further studies to determine significance are being conducted. 相似文献
72.
A multiple regression model is presented for the analysis of the components of individual change in clinical trials. Of primary interest is the condition where treatment effects vary according to patient baseline level. The model differentiates the average effects of treatment from baseline-dependent treatment effects, as well as identifying regression toward the mean and temporal effects. This model is applied in the analysis of data from a clinical trial of nutritional supplementation. 相似文献
73.
Proliferative epithelial breast lesions include a wide variety of benign hyperplastic and noninvasive neoplastic lesions, as well as invasive carcinomas. Mammographically these lesions may show microcalcifications, architectural distortions or mass lesions. The task of the pathologist begins with a preoperative diagnosis by means of minimally invasive biopsy. His diagnosis forms the basis for not only the radiological-pathological correlation diagnosis, but also for the management of benign proliferative breast disease lesions, as well as therapeutic decisions in the case of malignant lesions. In daily practice, immunohistochemistry is the method of choice for clarifying difficult cases. The aim of this chapter is to describe the relevant markers in breast pathology and to provide an algorithmic approach to different proliferative breast disease lesions. 相似文献
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Tympanostomy tube placement has clearly been shown to be an efficacious treatment for recurrent bouts of acute otitis media or chronic otitis media with effusion. However, there are few objective, prospective, randomized studies present in the literature to aid the clinical otolaryngologist with the proper tube choice for middle ear aeration. A prospective, randomized study was undertaken of four commonly used tympanostomy tubes. Shepard Teflon grommet, Armstrong beveled tube, Reuter-Bobbin tube, and Goode T-tube. This study was undertaken to determine which of these tubes had the fewest number of postplacement complications, including otorrhea, plugging, residual perforation, or chronic persistence in the tympanic membrane. Average follow-up was 17 months. The Shepard and Armstrong tubes showed a comparatively low rate of plugging and otorrhea. Both tubes had extrusion times that averaged less than 1 year. The Reuter-Bobbin tube had a much greater rate of plugging, compared to the other tubes. The T-tube had an increased incidence of otorrhea and persistence in the tympanic membrane well beyond 1 year. The T-tube was also the only tube in this study associated with residual perforations. 相似文献
77.
In 135 postmenopausal women ultrasonic findings of the endometrium were compared with the final histopathology. Object of this study was to evaluate the ability of metric structural criterions for a vaginosonographic screening of benign and malignant endometrial neoplasms. A sonographic assessment of the endometrium was possible in 97.8% of the patients; anatomic peculiarities such as calcified fibromyomata proved to be the main-impediments. By means of the criterions examined the sensitivity for the differentiation of inconspicuous and pathological findings was 100% with a 98.2% specificity; the rate of wrong-positive results was 1.6%. In 9.2% ultrasound was classified as conspicuous requiring further controls. According to these results the vaginosonographic assessment of the endometrium regarding its thickness and structure (homogeneity, echogeneity, median echo) can be recommended for a non-invasive screening for endometrial neoplasms. 相似文献
78.
PN McDOUGALL PM LOUGHNAN NT CAMPBELL M HOCHMANN BJ TIMMS WW BUTT 《Journal of paediatrics and child health》1995,31(4):292-296
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
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1,25-Dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] is an effective agent for inhibiting the growth of prostate cancer cells including LNCaP and PC-3 cell lines. However, the extent of growth inhibition in these cell lines differs because LNCaP cells are much more responsive than PC-3 cells. Previous studies in LNCaP cells have shown that 1,25-(OH)(2)D(3) treatment results in G(0)/G(1) cell cycle accumulation, loss of Ki67 expression, and induction of apoptosis. One difference between the two cell lines is that PC-3 cells lack functional p53, a protein that plays roles both in cell cycle regulation and induction of apoptosis. In this study, the role of p53 in 1,25-(OH)(2)D(3) action was examined using the p53-negative PC-3 cells and a line of LNCaP cells, called LN-56, in which p53 function was shut off using a dominant negative p53 fragment. We found that treatment with 1,25-(OH)(2)D(3) extensively inhibits growth of LN-56 prostate cancer cells lacking p53, but in contrast to the parental LNCaP cells, the LN-56 cells recover rapidly. Moreover, in prostate cancer cells, the synergism between 1,25-(OH)(2)D(3) and 9-cis retinoic acid appears to be dependent on the presence of functional p53; however, 1,25-(OH)(2)D(3)-mediated induction of G(1) cell cycle accumulation and induction of apoptosis is not. 相似文献