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Progesterone-associated endometrial protein (PAEP/PP14) is a 28-kD glycoprotein with sequence homology to beta-lactoglobulins containing a retinol-binding motif. PAEP/PP14 is present at nanomolar concentrations in human serum. It is produced by secretory and decidualized endometrium in women and by seminal vesicle epithelium in men. We report here that PAEP mRNA is constitutively expressed in normal hematopoietic tissue. Western immunoblotting of bone marrow cells with rabbit antibodies to PAEP gave a band at 28 kD, and immunocytochemical staining with monoclonal antibodies localized PAEP into the cytoplasm of erythroid precursors representing different stages of the normoblast series. PAEP was not detected in mature red blood cells, platelets, or in cells of the myeloid lineage. Untreated K562 leukemia cells did not contain PAEP, whereas treatment of the cells with tetradecanoylphorbol acetate (TPA) induced strong expression of PAEP mRNA and synthesis of the intact protein that was found both in the cytoplasm of the differentiating cells and in the supernatant of TPA-treated cultures. These findings add a new member to the growing family of genes that are constitutively expressed both in the reproductive tract and in the hematopoietic system.  相似文献   
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Objective : To compare the morbidities in the very low birthweight (VLBW; < 1500 g) and normal birthweight (NBW; ± 2500 g) Malaysian infants during the first year of life.
Methodology : Prospective observational cohort study of consecutive surviving VLBW infants and randomly sampled NBW infants born in the Kuala Lumpur Maternity Hospital between 1 December 1989 and 31 December 1992. Infants were followed up regularly during the first year of life, after correction for prematurity.
Results : Compared with NBW infants ( n = 106), VLBW infants ( n = 127) had significantly higher risk of failure to thrive (odds ratio [OR] = 8.0, 95% confidence intervals [Cl]: 1.1 to 354.3), wheezing (OR = 3.7, 95% Cl: 1.6 to 9.3), rehospitalization (OR = 2.3, 95% Cl: 1.1 to 5.0), cerebral palsy (OR = 8.6, 95% Cl: 2.0 to 77.6), neurosensory hearing loss (OR = 12.0, 95% Cl: 1.7 to 513.6) and visual loss (7.9 vs 0%, P = 0.002). The mean mental developmental index (MDI) and mean psychomotor developmental index (PDI) at 1 year of age were significantly lower among VLBW infants (MDI 99 [SD = 28], PDI89 [SD = 25]) than NBW infants (MDI 106 [SD = 18], PDI 101 [SD = 18]) (95% Cl for difference between means being MDI: -14.1 to -1.7; and PDI: -17.6 to -6.0). Logistic regression analysis showed that among VLBW infants: (i) male sex, Malay ethnicity and bronchopulmonary dysplasia were significant risk factors associated with wheezing; (ii) longer duration of oxygen therapy during the neonatal period, seizures after the post-neonatal period and wheezing were significant risk factors associated with rehospitalization; and (iii) longer duration of oxygen therapy during the neonatal period was a significant risk factor associated with adverse neurodevelopmental outcome during the first year of life.
Conclusions : Compared with NBW infants, VLBW Malaysian infants had significantly higher risks of physical and neurodevelopmental morbidities.  相似文献   
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Certain alkaloloids structurally related to acutumine haw been shown to possess extensive pharmacological activities in both the nervous and cardiovascular systems, although no report has been published concerning such activities with acutumine.The present study was undertaken in order to determine if acutumine possessed memory enhancing properties. Using a water-maze task in mouse, acutumine (40 to 80mg/kg, po) has been  相似文献   
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One of the most consistent results in the epidemiology of human breast cancer is the inverse relationship of risk and early full-term parity. The goal of this study was to investigate the molecular mechanisms through which early full-term pregnancy protects the breast from cancer development. We used Wistar-Furth (WF) rats as our experimental system and mimicked pregnancy using estrogen and progesterone (E/P). Sexually mature female rats were treated with steroid hormones for 21 days and after 28 days of gland involution, the rats were administered MNU. Rats that received a high dose of 20 microg E and 20 mg P exhibited an 82% reduction in the incidence of mammary adenocarcinomas as compared to the rats receiving only blank pellets. Decreasing doses of E/P were partially protective suggesting that complete differentiation of the gland was not required for refractoriness. We measured the RNA expression levels of several target genes involved in the regulation of mammary cell proliferation and/or differentiation including estrogen receptor (ER) and progesterone receptor (PR), cyclins D1 and D2, the cell cycle inhibitors p16, p21 and p27, and the tumor suppressor p53. At the time of MNU treatment we found no significant differences in the expression of these genes, with the possible exception of p21, indicating that hormone treatment did not result in constitutive changes in expression levels. The numbers of apoptotic cells were low and comparable in the hormone exposed and age-matched virgin gland (AMV) at the time of carcinogen challenge and remained low for 8 days after MNU treatment. The number of BrdU-labeled cells at the time of carcinogen challenge were also low in both the AMV (1.8%) and hormone exposed (0.8%) animals. In contrast, cell proliferation in the AMV (5.7%) was significantly different from both the parous involuted (1.2%) and the E/P-treated involuted (1.5%) animals 8 days after MNU treatment. We interpret these data to indicate that hormone treatment results in mammary epithelial cells that have persistent alterations in intracellular pathways governing proliferation responses to carcinogens.   相似文献   
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To determine the amount of blood lost, the number of transfusions, and the effectiveness of preoperative autologous blood donation in radical prostatectomy, 163 patients' records from 1987 to 1991 were reviewed at four university hospitals and three community hospitals. Calculated red cell volume lost was 1003 +/− 535 mL (mean +/− SD), which corresponds to 44 +/− 18 percent (mean +/− SD) of total red cell volume. Preoperative donation of blood for autologous use reduced the rate of transfusion of allogeneic blood from 66 to 20 percent (p < 0.001). Of the patients who donated 1 to 2 units, 32 percent received allogeneic blood; 14 percent of those who donated 3 units received allogeneic blood. Donation of 4 units reduced the allogeneic transfusion rate to 11 percent. However, as the number of units donated increased (1-3 units), the units not transfused also increased (0-21%). Ninety-one (56%) of 163 patients donated fewer than 3 units. Autologous blood donation is effective in minimizing the transfusion of allogeneic blood to radical prostatectomy patients, but many patients do not donate enough blood (< 3 units). The donation of 3 units of blood for autologous use is recommended for patients who undergo radical prostatectomy.  相似文献   
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