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1.
On the basis of results of studies using high doses of estrogens, exposure to estrogen during fetal life is known to inhibit prostate development. However, it is recognized in endocrinology that low concentrations of a hormone can stimulate a tissue, while high concentrations can have the opposite effect. We report here that a 50% increase in free-serum estradiol in male mouse fetuses (released by a maternal Silastic estradiol implant) induced a 40% increase in the number of developing prostatic glands during fetal life; subsequently, in adulthood, the number of prostatic androgen receptors per cell was permanently increased by 2-fold, and the prostate was enlarged by 30% (due to hyperplasia) relative to untreated males. However, as the free serum estradiol concentration in male fetuses was increased from 2- to 8-fold, adult prostate weight decreased relative to males exposed to the 50% increase in estradiol. As a model for fetal exposure to man-made estrogens, pregnant mice were fed diethylstilbestrol (DES) from gestation days 11 to 17. Relative to controls, DES doses of 0.02, 0.2, and 2.0 ng per g of body weight per day increased adult prostate weight, whereas a 200-ng-per-g dose decreased adult prostate weight in male offspring. Our findings suggest that a small increase in estrogen may modulate the action of androgen in regulating prostate differentiation, resulting in a permanent increase in prostatic androgen receptors and prostate size. For both estradiol and DES, prostate weight first increased then decreased with dose, resulting in an inverted-U dose-response relationship.  相似文献   
2.
Hyperimmune anti-human immunodeficiency virus immunoglobulin (HIVIG) is an intravenous immunoglobulin prepared from HIV-infected asymptomatic donors with a CD4 cell count greater than 400 cells/microl and a high titer of antibody to HIV-1 p24 protein. Twelve persons with AIDS received four doses of HMG (two at 50 mg/kg of body weight and then two at 200 mg/kg) every 28 days. Pharmacokinetics were evaluated by measurement of anti-p24 antibody. HIVIG was well tolerated, and all participants completed the study. Three subjects who were not receiving Pneumocystis carinii pneumonia (PCP) prophylaxis developed PCP. The mean value for HIVIG clearance was 3.02 ml/kg/day at 50 mg/kg and 3.65 ml/kg/day at 200 mg/kg (P = 0.027); the mean trough antibody titers (reciprocal units) were 1,442 and 4,428, respectively. This study indicates that high titers of anti-p24 antibody can be maintained with a monthly administration schedule of HIVIG and that short-term safety is acceptable. Comparisons to evaluate the therapeutic potential of HIVIG are justified.  相似文献   
3.
OBJECTIVE: To determine plasma levels of insulin-like growth factor-I (IGF-I), CA-125, estrone (E1), E2, and P in women with uterine leiomyomas compared with normal women. DESIGN: Women with leiomyomas were compared with normal women (control). SETTING: University Department of Obstetrics and Gynecology. PATIENTS: Fifty-one premenopausal women with uterine myomas > 14 weeks gestation and 30 normal fertile women (controls) were studied. Peripheral blood samples were obtained before myomectomy or hysterectomy and during the nonmenstruating phase in the controls. MAIN OUTCOME MEASURES: Plasma levels of E1, E2, P, CA-125, and IGF-I were determined by specific and sensitive RIAs and immunoradiometric assays. RESULTS: Plasma IGF-I levels were 2,006 +/- 185 mU/mL (mean +/- SEM, n = 35) and 2,335 +/- 287 mU/mL (n = 16) in women with leiomyomas during the follicular and luteal phases, respectively, whereas the corresponding values for normal women were 1,702 +/- 120 (n = 30) and 1,774 +/- 239 mU/mL (n = 30). Similarly, plasma CA-125 levels were unchanged in women with leiomyomas (myomas: 18.8 +/- 2.4, 21.5 +/- 3.7 U/mL; normal: 15.9 +/- 1.5, 15.8 +/- 1.3 U/mL during follicular and luteal phases, respectively). Women with leiomyomas had plasma E1, E2, and P levels during the follicular phase (91.9 +/- 11.5 pg/mL; conversion factor to SI unit, 3.699; 94.6 +/- 19.0 pg/mL; conversion factor to SI unit, 3.671; and 1.5 +/- 0.4 ng/mL; conversion factor to SI unit, 3.180, respectively) and the luteal phase (105.8 +/- 11.2 pg/mL; conversion factor to SI unit, 3.699; 128.7 +/- 24.8 pg/mL; conversion factor to SI unit, 3.671; and 9.6 +/- 1.6 ng/mL; conversion factor to SI unit, 3.180) similar to normal women. CONCLUSION: Plasma levels of IGF-I, CA-125, E1, E2, and P are normal in women with leiomyomas.  相似文献   
4.
A role for endogenous histamine and its H3 receptor subtype for mediating drinking elicited by eating was examined in adult male Sprague-Dawley rats. The i.p. injection of the H3 agonist R-alpha-methylhistamine (Ramh, 2.5 mg/kg) shortened the latency to initiate drinking and increased 1-h water intake in nondeprived rats freely eating pellets and drinking water. The ICV injection (through a surgically implanted chronic cannula) of 10 micrograms Ramh increased water intake; this Ramh-induced drinking was abolished by previous ICV injection of the H3 antagonist thioperamide (Th, 60 micrograms). For rats drinking and eating after 24-h food deprivation, s.c. Th inhibited drinking behavior: for example, 10 mg/kg Th s.c. delayed the latency to initiate drinking and inhibited 1-h water intake without inhibition of food intake. In contrast, 60 micrograms Th ICV failed to inhibit food-related drinking in rats eating after food deprivation. For nondeprived rats eating a small cracker, 10 mg/kg Th s.c. delayed the latency to initiate drinking and abolished water intake without effect of eating, and 60 micrograms Th ICV had similar effects upon drinking elicited by ingestion of cracker. The IG infusion (through a surgically implanted gastric catheter) of 2 ml 600 or 900 mOsm/kg NaCl, a treatment that is subthreshold for increase in systemic plasma osmolality at the initiation of drinking, elicited drinking that was abolished by 10 mg/kg Th s.c. and attenuated by 60 micrograms Th ICV. The IG infusion of 2 ml 1800 mOsm/kg NaCl, a treatment that is above threshold for increase in systemic plasma osmolality, elicited drinking that was attenuated by 10 mg/kg s.c. or 60 micrograms Th ICV. These results demonstrate that peripheral and central H3 receptors for histamine have a role in drinking elicited by eating and the postprandial gastrointestinal osmotic consequences of eating. These findings extend the evidence demonstrating a histaminergic contribution to food-related drinking in rats.  相似文献   
5.
The use of a recombinant poxvirus (RPV) strain, expressing HBsAg in the process of reproduction in different bioreactor systems under stationary and bioreactor conditions of cultivation, made it possible to obtain highly purified HBsAg. The identity and purity of HBsAg was confirmed by the analysis of its amino acid composition, SDS electrophoresis in polyacrylamide gel, electron microscopy and high-performance liquid chromatography. Good prospects of the use of RPV-expressed gene engineering HBsAg as the basis vaccines against hepatitis B was demonstrated in 10 experimental batches of vaccine. All batches of the preparation had pronounced immunogenicity and were safe and nontoxic in animal experiments. The ID50 of experimental batches did not exceed 211 ng/ml, which, according to the data of comparative experiments, was lower than, or equal to, corresponding values of analogous foreign commercial preparations, based on plasma or yeast HBsAg.  相似文献   
6.
Thirteen hundred and fifty dogs were examined under anesthesia at veterinary hospitals in the USA and Canada. Periodontal health was recorded in detail. Teeth were frequently absent (particularly lower third molar, upper and lower first premolars, and incisor teeth). Calculus was most extensive on the upper fourth premolar and molar teeth. Missing teeth, mobility of remaining teeth, extent of calculus and gingival inflammation, and furcation exposure and attachment loss all were more common in small dogs compared with larger dogs, and in order dogs compared with younger dogs.  相似文献   
7.
This review examines the consequences of social deprivation on brain chemistry and behavior on rats. Although social deprivation produces wide-ranging behavioral and neurochemical effects, it appears that these effects are determined by a number of factors, the most critical factor being the age or developmental stage during the period of deprivation. Roughly, the effects examined in this review may be separated into three major developmental stages and each is related to deprivation of specific types of social interaction: preweaning/neonatal, postweaning/adolescent, and adult. The effects of social deprivation during each of these stages appears to be neurochemically and behaviorally specific. However, much of the research to date has failed to examine deprivation during specific stages, often combining deprivation of different types. Nonetheless, these modifications of experience produce animals of differing phenotypes, which could be characterized as pathological in nature in many instances, and may model particular aspects of human psychopathologies or perhaps the propensity to develop those phenotypic features.  相似文献   
8.
9.
OBJECTIVES: (a) To examine the frequency, type, and severity of complications occurring in a pediatric intensive care unit; (b) to identify populations at risk; and (c) to study the impact of complications on morbidity and mortality. DESIGN: Prospective survey. SETTING: Pediatric intensive care unit (PICU) of a university-affiliated hospital. PATIENTS: 1035 consecutive admissions over an 18-month period. RESULTS: 115 complications occurred during 83 (8.0%) admissions, for 2.7 complications per 100 PICU-days; 48 (42%) complications were major, 45 (39%) moderate, and 22 (19%) minor. Sixty complications (52%) were ventilator-related, 14 were drug-related, 13 procedure-related, 24 infectious, and 22 involved invasive devices (18 vascular catheters). Human error was involved in 41 (36%) cases, 21 of which were major (18%). Treatments included reintubation < 24 h (28), intravenous antimicrobials (24), and invasive bedside procedures (14). Cardiopulmonary resuscitation was required in 6 patients. Thirteen patients with complications died (15.7%); 2 deaths were directly due to complications. Patients with complications were younger, had longer lengths of stay, and had a higher mortality. Length of stay was a positive risk factor for complication risk (odds ratio = 1.09, 95% confidence interval: 1.05 to 1.13; p = 0.0001); other patient characteristics had no predictive effect. Kaplan-Meier estimates showed that the most severe complications occurred early in the PICU stay. The best indicators of patient mortality were number of complications (odds ratio = 2.96, 95% confidence interval 1.72 to 5.08; p = 0.0001), and mortality risk derived from the Pediatric Risk of Mortality Score (odds ratio = 1.08, 95% confidence interval 1.06 to 1.10; p = 0.0001). Mortality was correlated with increasing severity of complications. CONCLUSION: Complications have a significant impact on patient care. Patients may be at increased risk earlier in their PICU course, when the number of interventions may be greatest. Complications may increase patient mortality and predict patient death better than other patient variables.  相似文献   
10.
The EMS1 and CCND1 genes at chromosome 11q13 are amplified in about 15% of primary breast cancers but appear to confer different phenotypes in ER positive and ER negative tumours. Since there are no published data on EMS1 expression in large series of breast cancers we examined the relationship of EMS1 expression with EMS1 gene copy number and expression of mRNAs for cyclin D1 and ER. In a subset of 129 patients, where matched tumour RNA and DNA was available, EMS1 mRNA overexpression was associated predominantly with gene amplification (P = 0.0061), whereas cyclin D1 mRNA overexpression was not (P = 0.3142). In a more extensive series of 351 breast cancers, there was no correlation between cyclin D1 and EMS1 expression in the EMS1 and cyclin D1 overexpressors (P = 0.3503). Although an association between EMS1 mRNA expression and ER positivity was evident (P = 0.0232), when the samples were divided into quartiles of EMS1 or cyclin D1 mRNA expression, the increase in the proportion of ER positive tumours in the ascending EMS1 mRNA quartiles was not statistically significant (P = 0.0951). In marked contrast there was a significant stepwise increase in ER positivity in ascending quartiles of cyclin D1 mRNA (P = 0.030). A potential explanation for this difference was provided by the observation that in ER positive breast cancer cells oestradiol treatment resulted in increased cyclin D1 gene expression but was without effect on EMS1. The relationship between EMS1 expression and clinical outcome was examined in a subset of 234 patients with median follow-up of 74 months. High EMS1 expression was associated with age > 50 years (P = 0.0001), postmenopausal status (P = 0.0008), lymph node negativity (P = 0.019) and an apparent trend for worse prognosis in the ER negative subgroup. These data demonstrate that overexpression of EMS1 mRNA is largely due to EMS1 gene amplification, is independent of cyclin D1 and ER expression and, in contrast to cyclin D1, is not regulated by oestrogen. Independent overexpression of these genes may confer different phenotypes and disease outcomes in breast cancer as has been inferred from recent studies of EMS1 and CCND1 gene amplification.  相似文献   
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