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101.
M D Rifkin E A Zerhouni C A Gatsonis L E Quint D M Paushter J I Epstein U Hamper P C Walsh B J McNeil 《The New England journal of medicine》1990,323(10):621-626
BACKGROUND. In 1987, a cooperative study group consisting of five institutions was formed to determine the relative benefits of magnetic resonance imaging (MRI) and endorectal (transrectal) ultrasonography in evaluating patients with clinically localized prostate cancer (stage Ta or Tb). METHODS. Over a period of 15 months, 230 patients were entered into the study and evaluated with identical imaging techniques. We compared imaging results with information obtained at the time of surgery and on pathological analysis. RESULTS. MRI correctly staged 77 percent of cases of advanced disease and 57 percent of cases of localized disease; the corresponding figures for ultrasonography were 66 and 46 percent (P not significant). These figures did not vary significantly between readers; moreover, simultaneous interpretation of MRI and ultrasound scans did not improve accuracy. In terms of detecting and localizing lesions, MRI identified only 60 percent of all malignant tumors measuring more than 5 mm on pathological analysis and ultrasonography identified only 59 percent. CONCLUSIONS. The MRI and ultrasonography equipment that is currently available is not highly accurate in staging early prostate cancer, mainly because neither technique has the ability to identify microscopic spread of disease. Further evaluation with improved equipment may improve the accuracy of these techniques. 相似文献
102.
Surgery in the treatment of varicose veins 总被引:1,自引:0,他引:1
To identify variables which might influence the results of varicose vein surgery, a ten-year retrospective study was carried out on 612 patients undergoing varicose vein surgery. Patient symptomatology, type of venous insufficiency and operator experience were examined and correlated with the results of surgery. The female-to-male ratio was 2:1. The mean age was 47 years for women, 45 years for men. A family history of varicose veins was recorded in 74% of patients. A history of previous deep venous thrombosis was reported in 5% of cases, but in the sub-group of patients with stasis ulceration, the incidence was 9%. Cosmetic appearance was the commonest presenting complaint (54%), while ulceration was relatively infrequent (14%). There was moderate-to-marked improvement in 86% of cases at one year. This was sustained in 79% at three years, in 75% at five years and in 74% at ten years. There was no correlation between the type of venous insufficiency or the presenting complaint, and the result of surgery. Operator experience had the most significant effect on the outcome of surgery (P less than 0.001). Our findings indicate that varicose vein surgery offers most patients a satisfactory result. The only significant variable was operator experience. We strongly recommend closer supervision of junior staff performing this type of surgery, particularly as a large proportion of these patients (25% in this study) are operated on by the more junior staff. 相似文献
103.
Reduction of morbidity and mortality rates for neonatal group B streptococcal disease through early diagnosis and chemoprophylaxis. 总被引:9,自引:7,他引:9 下载免费PDF全文
Pregnant women, part of the term service population at Orlando Regional Medical Center, were screened for group B streptococci (GBS), using Lim Group B Strep Broth (GIBCO Laboratories, Madison, Wis.) and the Phadebact Strep B Test (Pharmacia Diagnostics, Piscataway, N.J.). Of the 803 women screened, 173 were confirmed as colonized with GBS at the time of admission in labor. Eighty of these women were treated with ampicillin at least 6 h prior to delivery. The remaining 93 women received no ampicillin. None of the infants born to the treated women was colonized with GBS at surface culture sites. Forty-three of the infants born to untreated women were colonized. Rapid identification of GBS colonization in women, combined with ampicillin chemoprophylaxis, significantly reduced vertical transmission of GBS. 相似文献
104.
Anderson LV Davison K Moss JA Young C Cullen MJ Walsh J Johnson MA Bashir R Britton S Keers S Argov Z Mahjneh I Fougerousse F Beckmann JS Bushby KM 《Human molecular genetics》1999,8(5):855-861
Recently, a single gene, DYSF, has been identified which is mutated in patients with limb-girdle muscular dystrophy type 2B (LGMD2B) and with Miyoshi myopathy (MM). This is of interest because these diseases have been considered as two distinct clinical conditions since different muscle groups are the initial targets. Dysferlin, the protein product of the gene, is a novel molecule without homology to any known mammalian protein. We have now raised a monoclonal antibody to dysferlin and report on the expression of this new protein: immunolabelling with the antibody (designated NCL-hamlet) demonstrated a polypeptide of approximately 230 kDa on western blots of skeletal muscle, with localization to the muscle fibre membrane by microscopy at both the light and electron microscopic level. A specific loss of dysferlin labelling was observed in patients with mutations in the LGMD2B/MM gene. Furthermore, patients with two different frameshifting mutations demonstrated very low levels of immunoreactive protein in a manner reminiscent of the dystrophin expressed in many Duchenne patients. Analysis of human fetal tissue showed that dysferlin was expressed at the earliest stages of development examined, at Carnegie stage 15 or 16 (embryonic age 5-6 weeks). Dysferlin is present, therefore, at a time when the limbs start to show regional differentiation. Lack of dysferlin at this critical time may contribute to the pattern of muscle involvement that develops later, with the onset of a muscular dystrophy primarily affecting proximal or distal muscles. 相似文献
105.
D Dao C P Walsh L Yuan D Gorelov L Feng T Hensle P Nisen D J Yamashiro T H Bestor B Tycko 《Human molecular genetics》1999,8(7):1337-1352
106.
Effect of age and preexisting antibody on serum antibody response of infants and children to the F and G glycoproteins during respiratory syncytial virus infection. 总被引:8,自引:3,他引:8 下载免费PDF全文
B R Murphy D W Alling M H Snyder E E Walsh G A Prince R M Chanock V G Hemming W J Rodriguez H W Kim B S Graham et al. 《Journal of clinical microbiology》1986,24(5):894-898
The serum antibody response of 50 infants and children infected with respiratory syncytial virus (RSV) was determined by a glycoprotein-specific enzyme-linked immunosorbent assay, and the effects of age and preexisting antibody titer at the time of RSV infection on response to the G and F glycoproteins of RSV were examined. The immune response to the G and F glycoproteins was assessed with anti-human immunoglobulin A to permit measurement of the response of young infants in the presence of maternally derived immunoglobulin G. The findings suggested that age primarily affects the response to the F glycoprotein and that preexisting antibody titer affects the response to the G glycoprotein. 相似文献
107.
Germinal center and activated b-cell profiles separate Burkitt lymphoma and diffuse large B-cell lymphoma in AIDS and non-AIDS cases 总被引:1,自引:0,他引:1
Gormley RP Madan R Dulau AE Xu D Tamas EF Bhattacharyya PK LeValley A Xue X Kumar P Sparano J Ramesh KH Pulijaal V Cannizzaro L Walsh D Ioachim HL Ratech H 《American journal of clinical pathology》2005,124(5):790-798
Morphologic features of Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) overlap. No single phenotypic marker or molecular abnormality is pathognomonic. We tested a panel of 8 germinal center (GC) and activated B-cell (ABC) markers for their ability to separate BL and DLBCL. We diagnosed 16 BL and 39 DLBCL cases from 21 patients with AIDS and 34 without AIDS based on traditional morphologic criteria, Ki-67 proliferative index, and c-myc rearrangement (fluorescence in situ hybridization). After immunohistochemically staining tissue microarrays of BL and DLBCL for markers of GC (bcl-6, CD10, cyclin H) and ABC (MUM1, CD138, PAK1, CD44, bcl-2), we scored each case for the percentage of positive cells. Hierarchical clustering yielded 2 major clusters significantly associated with morphologic diagnosis (P < .001). For comparison, we plotted the sum of the GC scores and ABC scores for each case as x and y data points. This revealed a high-GC/low-ABC group and a low-GC/high-ABC group that were associated significantly with morphologic diagnosis (P < .001). Protein expression of multiple GC and ABC markers can separate BL and DLBCL. 相似文献
108.
The alloimmune response can be divided into specific junctures where critical decisions between tolerance and immunity are made which define the outcome of the transplant. At these "decision nodes" various cytokines direct alloresponsive T cells to develop either a proinflammatory response aimed at graft destruction or an immunoregulatory response facilitating graft acceptance. This review will focus on the role of these cytokines in influencing the progression of an alloimmune response leading ultimately to either allograft survival or rejection. 相似文献
109.
K. B. Walsh S. H. Bryant A. Schwartz 《Pflügers Archiv : European journal of physiology》1987,409(1-2):217-219
The calcium channel-inhibiting drugs nitrendipine and diltiazem represent two important classes of organic calcium antagonists. In the present study, the effect of these drugs on calcium currents and charge displacement currents in bullfrog semitendinosus muscle fibers was examined using a vaseline gap voltage clamp. Nitrendipine (10 M) reduced the quantity of charge that moved both during the ON phase (QON) and the OFF phase (QOFF) of charge movement. This action appeared to be most selective for QON. However, at this same concentration, nitrendipine had no blocking action on inward calcium currents. In contrast to these findings, diltiazem blocked calcium currents in a concentration-dependent manner, while slightly increasing the quantity of charge moved during QON and QOFF. The enhancement of charge movement by diltiazem resulted from two actions. First, diltiazem shifted the voltage-dependence of charge movement to more negative potentials. Second, diltiazem increased the maximum amount of charge moved. (Supported by NIH NS 03178 and HL 07382.) 相似文献
110.
Raymond J. Walsh James R. Brawer Peck Sun Lin 《Anatomical record (Hoboken, N.J. : 2007)》1978,190(2):257-269
Supraependymal cells in the third ventricle of neonatal male and female rats were examined with scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Supraependymal cells in the third ventrical of adult male rats were also studied with SEM. Many neonate supraependymal cells were round to oval in shape and exhibited varying degrees of surface irregularity. Small finger-like processes or narrow pseudopodia projected from the cell bodies over the underlying ependymal cells. Some neonatal supraependymal cells exhibited flattened cell bodies with broad pseudopodia and few surface irregularities. TEM revealed a variety of cell profiles. Prominent within the cytoplasm of many supraependymal cells were lysosomes, smooth and coated vesicles suggesting pinocytosis, subplasmalemma vacuoles, and occasional lipid droplets. The morphological characteristics of neonatal supraependymal cells suggested they were mononuclear phagocytes. Adult supraependymal cells exhibited more pleomorphic cell shapes with numerous cell processes, varying widely in size and shape, and often extending over the ventricular surface for considerable distances. These observations, in combination with previous studies by other investigators, suggest that some adult supraependymal cells may also be phagocytic in nature. The differences in morphology between adult and neonatal supraependymal phagocytes may relate to the differing third ventricle environment between adult and neonates and/or differences in the origin of the phagocytes with age. 相似文献