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41.
E. Mendelson P. Duvdevani N. Varsano Y. Lerman R. Slepon R. Dagan D. Cohen Y. Danon T. Shohat 《Journal of medical virology》1996,50(3):249-253
In order to evaluate the true immune status and the effect of revaccination on a young adult population, we collected serum samples from 289 military recruits who were vaccinated during an outbreak in 1991. Most vaccinees, age 18–25 years, had apparently been immunized once before as infants. Sera collected just prior to the vaccination and 14 and 28 days afterwards were tested for measles antibodies by hemagglutination inhibition (HI) and enzyme-linked immunosorbent assay (ELISA)-IgM. Before vaccination, 46 (15.9%) of the subjects had no HI antibodies, (<1:4) and 48 (16.6%) had borderline (1:4) HI titer. Following vaccination, only ten (3.5%) remained negative and 19 (6.6%) had borderline titer. The increase in HI antibody titer was inversely proportional to the prevaccination titer, and 159 subjects (55.0%) showed no increase at all. The geometric mean titer (GMT) rose from 9.14 to 21.47. Among the prevaccination-negative subjects (HI <1:4) 28 (60.9%) reached a postvaccination titer of ≥ 1:8, and eight (17.4%) reached a titer of 1:4. Twelve (26.1%) of the negative subjects seroconverted and developed IgM, 16 (35%) seroconverted without IgM, and 18 (39%) remained negative and did not develop IgM. A group of eight vaccinees with prevaccination titer of ≥ 1:4 developed IgM. Some were probably infected by the circulating wild-type virus prior to the vaccination. Thus, a total number of 20 of the 289 subjects studied (6.9%) had true negative preimmune status as judged by the IgM test. However, the vaccination campaign prevented further measles cases, apparently by increasing the population's immunity, particularly in individuals with very low titers or without measles antibodies. © 1996 Wiley-Liss, Inc. 相似文献
42.
Richard M Mendelson 《Journal of Medical Imaging and Radiation Oncology》2020,64(3):353-360
Inappropriate diagnostic imaging (DI) is a burgeoning issue and embraces its overuse and its misapplication. The obverse problem is one of underuse – that is when patients who should undergo imaging fail to do so. This article attempts to define these problems, examines the causes and effects and suggests some potential solutions. 相似文献
43.
William R. Phipps Scott E. Lukas Jack H. Mendelson James Ellingboe Susan L. Palmieri Isaac Schiff 《Psychoneuroendocrinology》1987,12(6):459-465
Plasma levels of LH, FSH, prolactin (PRL), and testosterone (T) were assessed in six normal men following administration of a pharmacologic dose of gonadotropin releasing hormone (GnRH) (500 μg iv over a one-min period) with concomitant oral administration of either ethanol (0.695 g/kg of body weight over a 15-min period) or ethanol placebo. p] Acute ethanol administration had no effect on the response of either LH or FSH to GnRH. PRL levels increased following GnRH and administration of both ethanol and ethanol placebo. Ethanol administration enhanced the T response to GnRH (p < 0.001 vs placebo). During the placebo condition, T levels did not rise significantly until 100 min after GnRH administration, at which time the mean increment over baseline was 101 ± 20 ng/dl (±SEM). In contrast, following ethanol intake, T levels were significantly elevated within 30 min after GnRH administration, at which time the mean increment over baseline was 187 ± 42 ng/dl. The mean T increments were 304 ± 62 and 472 ± 77 ng/dl, respectively, 60 and 105 min following GnRH and ethanol administration. p] The increase in T levels following acute ethanol intake and concomitant gonadotropin stimulation is in contrast to the well-documented effect of chronic ethanol intake on suppression of testosterone synthesis by testicular Leydig cells. 相似文献
44.
The production of prostaglandin E2 (PGE2) by human amnion cells in primary monolayer culture was stimulated 2- to 150-fold by mouse epidermal growth factor (mEGF). The effect of mEGF on amnion cell PGE2 production was dependent on the time of treatment and the concentration of mEGF used. The rate of PGE2 production by these cells was maximal between 2 and 4 h of treatment with mEGF; thereafter, the rate of production of PGE2 declined. The stimulation of PGE2 production was maximal at concentrations of mEGF of greater than 5 ng/ml. A number of other growth factors, steroid and protein hormones, and various other test agents were ineffective or only minimally in stimulating PGE2 production by amnion cells. The stimulatory effect of mEGF on PGE2 production in these cells was dependent on the presence of serum in the culture medium; alternatively, mEGF was effective in stimulating PGE2 production by amnion cells in serum-free medium that was supplemented with arachidonic acid bound to albumin. Thus, we conclude that the marked stimulation of PGE2 production by amnion cells treated with mEGF is not due to an action of mEGF to stimulate the release of arachidonic acid from cellular glycerophospholipid storage forms; rather, these data are supportive of the conclusion that mEGF-stimulated PGE2 production is dependent on the presence of nonesterified, i.e., free, arachidonic acid in the medium. 相似文献
45.
Ethanol at low doses produces a release of punished responding in an operant rat conflict test similar to that observed for benzodiazepines and phenobarbital. It has been hypothesized that these anti-punishment effects are mediated via the GABA-benzodiazepine receptor-ionophore complex but not at the benzodiazepine binding site. In the present study isopropylbicyclophosphate (IPPO), which binds at the picrotoxinin site, reversed the release of punished responding produced by ethanol, pentobarbital and chlordiazepoxide; at low doses IPPO (less than 10 micrograms/kg) appeared to be most effective against ethanol but at higher doses (greater than 15 micrograms/kg) was also effective against pentobarbital and chlordiazepoxide. At still higher doses IPPO produced a decrease in punished and unpunished responding. These results suggest that the "anxiolytic" actions of ethanol may involve a direct action on the GABA-benzodiazepine receptor-ionophore complex and this action may underlie some of the intoxicating effects of ethanol. 相似文献
46.
Kremer CL Klein RR Mendelson J Browne W Samadzedeh LK Vanpatten K Highstrom L Pestano GA Nagle RB 《The Prostate》2006,66(11):1203-1212
BACKGROUND: The PI3K/AKT/mTOR pathway is central to prostate cancer progression. A preliminary investigation of immuno-histochemical expression of mammalian target of rapamycin (mTOR) pathway markers was undertaken to identify patterns of expression in prostate tissue. METHODS: Immunohistochemistry was performed on a custom-made prostate tissue array. Mean long scores and variability of long scores for each marker were recorded for normal lumenal cells, prostate intraepithelial neoplasia (PIN), and cancer. RESULTS: Expression of PTEN decreased and mTOR signaling pathway markers increased in PIN and in cancer as compared to normal cells in the majority of samples. Overexpression of 4E-BP1 and p-4E-BP1 was observed in PIN and cancer. However, in cancer, the overexpression of 4E-BP1 was significantly higher than with any other marker. DISCUSSION: Results suggest that 4E-BP1 overexpression is strongly associated with prostate cancer, especially when combined with PTEN and mTOR expression data. Hierarchical clustering analysis utilizing PTEN, mTOR, and 4E-BP1 separated normal from cancer cell populations in most cases. 相似文献
47.
Yael Gozlan Daniella Aaron Yana Davidov Maria Likhter Gil Ben Yakov Oranit Cohen-Ezra Orit Picard Oran Erster Ella Mendelson Ziv Ben-Ari Fadi Abu Baker Orna Mor 《Viruses》2022,14(3)
A comprehensive characterization of chronic HBV (CHB) patients is required to guide therapeutic decisions. The cumulative impact of classical and novel biomarkers on the clinical categorization of these patients has not been rigorously assessed. We determined plasma HBV-RNA and HBsAg levels, HBV in peripheral lymphocytes (PBMCs) and HBV mutation profiles in CHB patients. Patient demographics (n = 139) and classical HBV biomarkers were determined during a clinical routine. HBV-RNA in plasma and HBV-DNA in PBMCs were determined by RT-PCR. HBsAg levels were determined using Architect. In samples with HBV-DNA viral load >1000 IU/mL, genotype mutations in precore (PC), basal core promoter (BCP), HBsAg and Pol regions were determined by sequencing. Most patients (n = 126) were HBeAg-negative (HBeAgNeg) with significantly lower levels of HBV-RNA, HBV-DNA and HBsAg compared to HBeAg-positive (HBeAgPos) patients (p < 0.05). HBV genotype D prevailed (61/68), and >95% had BCP/PC mutations. Escape mutations were identified in 22.6% (13/63). HBeAgNeg patients with low levels of HBsAg (log IU ≤ 3) were older and were characterized by undetectable plasma HBV-DNA and undetectable HBV-RNA but not undetectable HBV-DNA in PBMCs compared to those with high HBsAg levels. In >50% of the studied HBeAgNeg patients (66/126), the quantitation of HBsAg and HBV-RNA may impact clinical decisions. In conclusion, the combined assessment of classical and novel serum biomarkers, especially in HBeAgNeg patients, which is the largest group of CHB patients in many regions, may assist in clinical decisions. Prospective studies are required to determine the real-time additive clinical advantage of these biomarkers. 相似文献
48.
Bryan C. Mendelson Steve R. Jacobson Alain M. Lavoipierre Richard J. Huggins 《Aesthetic plastic surgery》2010,34(4):455-461
Facial appearance is largely determined by the morphology of the underlying skeleton. Hydroxyapatite is one of several materials
available to enhance projection of the facial skeleton. This study evaluated the long-term maintenance of augmented bony projection
when porous hydroxyapatite granules are used on the facial skeleton. Ten female patients aged 28–58 years were studied following
aesthetic augmentation of the facial skeleton at 24 sites using porous hydroxyapatite granules. Postoperative CT scans at
3 months served as the baseline measurement and compared with scans taken at 1 and 2 years, with the thickness of the hydroxyapatite
measured in axial and coronal planes. Thickness of original bone plus overlay of hydroxyapatite, thickness of the overlying
soft tissue, and the overall projection (bone plus soft tissue) were recorded. It was found that 99.7% of the hydroxyapatite
was maintained at 2 years, with no statistical difference (t test) from the baseline measurement. The overall projection (bony and soft tissue) was maintained as there was no evidence
of native bone resorption or soft tissue atrophy. Radiographic results confirmed that the use of porous hydroxyapatite granules
for enhancement of the facial skeleton is not only a predictable procedure, but maintains full bony projection at 2 years. 相似文献
49.
50.
Age-related changes in the visual cortex 总被引:10,自引:0,他引:10
The ability to accurately perceive the speed of moving objects is one of many visual functions that decline with age. One factor that may contribute to this is a deterioration in temporal processing speed. At present, there is a dearth of information concerning how this may occur in the central nervous system, particularly in the visual cortex. Thus, in the present study, we investigated the neural basis of speed and temporal processing in areas 17 and 18 of visual cortex in young and aged rats using either a moving bar of light or a series of flashing lights. Our results showed that the mean preferred speed of a moving bar of light was significantly reduced in aged as compared to young animals. We also found that cells recorded from young animals were able to entrain to a higher frequency of flashing light stimuli than those recorded from aged animals. In addition, we found no age-related differences between cortical fields. These results suggest an age-related difference in temporal processing speed at the level of visual cortex. 相似文献