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991.
Utilization of the complement system offers potential for the elimination of tumor cells by monoclonal antibodies (mAb) immunotherapy. Activation of the complement system causes tumor cell destruction by inducing complement lysis and promoting cell-mediated killing. In addition, complement can induce a strong inflammatory response, which might enhance other antitumor effector mechanisms. An important targets for mAb immunotherapy, however, are membrane bound complement regulatory glycoprotein: CD46, CD55 and CD59, which have been found to be expressed on most tumor cells in vivo and in vitro. Blocking or down regulation of these inhibitors could be an important step in the advancement of mAb immunotherapy.  相似文献   
992.
OBJECTIVE: In June 2000, Oregon implemented a citizen-initiated ballot measure that grants adult adoptees access to their birth records, which contain their birth parents' identifying information. Because other states are considering similar policy changes, the authors explored whether Oregon's new law is meeting the information needs of adoptees. METHODS: Birth records were abstracted for a 9% (221/2,529) random sample of adoptees who obtained their records from June 20, 2000, to July 20, 2000, to describe the population and the information they obtained. Telephone interviews documented their motivations, expectations, and whether they considered the birth record useful. RESULTS: The mean age of the adoptees was 41 years, 64% were female, and 97% were white. Virtually all received information about their birth mother; however, only one-third received information about their birth father. Of the 221 sampled, 123 (59%) participated in the telephone survey, 12 were ineligible, 84 could not be reached, and 2 refused. The most common motivations for requesting records were to find birth parents (29%) and to obtain medical information (29%). Twenty-nine percent received less information than they expected, with many expecting, but not receiving, birth father information. Thirty-three (47%) of the 70 adoptees who tried to find their birth mother were successful. The records were considered "very" useful by 52% of respondents, "somewhat" or "a little" useful by 42%, and "not at all" useful by 6%. CONCLUSIONS: The results indicate that many adoptees received less information than they expected, and many did not meet their goals of finding birth parents or obtaining medical information. Nonetheless, the majority considered their birth records useful and important.  相似文献   
993.
Ten fish mortality events, involving primarily Atlantic menhaden, occurred from early July through September 2000 in several bays and creeks in Delaware, USA. Two events involved large mortalities estimated at 1-2.5 million fish in Bald Eagle Creek, Rehoboth Bay. Samples from Indian Inlet (Bethany Beach), open to the Atlantic, as well as from an enclosed area of massive fish kills at nearby Bald Eagle Creek and Torque Canal were collected and sent to our laboratory for analysis. Microscopic examination of samples from the fish kill site revealed the presence of a single-cell Raphidophyte alga Chattonella cf. verruculosa at a maximum density of 1.04 x 10(7) cells/L. Naturally occurring brevetoxins were also detected in the bloom samples. Besides the Chattonella species, no other known brevetoxin-producing phytoplankton were present. Chromatographic, immunochemical, and spectroscopic analyses confirmed the presence of brevetoxin PbTx-2, and PbTx-3 and -9 were confirmed by chromatographic and immunochemical analyses. This is the first confirmed report in the United States of brevetoxins associated with an indigenous bloom in temperate Atlantic estuarine waters and of C. cf. verruculosa as a resident toxic organism implicated in fish kills in this area. The bloom of Chattonella continued throughout September and eventually declined in October. By the end of October C. cf. verruculosa was no longer seen, nor was toxin measurable in the surface waters. The results affirm that to avoid deleterious impacts on human and ecosystem health, increased monitoring is needed for brevetoxins and organism(s) producing them, even in areas previously thought to be unaffected.  相似文献   
994.
The number of juveniles in correctional facilities is growing. These youth tend to have significant medical and mental health problems, yet they are underserved with respect to health care. Health care providers can work to improve the health status of incarcerated youth by pushing for improved funding of and standards for their health care and for their increased access to care while they are in correctional facilities and after they are released. This article presents a summary of statistics about the rates of youth incarceration and about the health status of such youth. It also offers recommendations for improving the health care of juveniles involved with the justice system.  相似文献   
995.
The contractile activity of the isolated myometrium of pregnant women with mycoplasma, chlamydia and mixed infections has been studied by pharmacological organ bath method. We found that mycoplasma infection decreased while chlamydia or mixed infection increased myometrium contraction evoked by oxytocin or prostaglandin F2alpha. The results of this study could be important for the prediction of possible complications during pregnancy and labour in women with chronic specific urogenital infections.  相似文献   
996.
997.
OBJECTIVE: This study investigated prospective predictors of lifetime history diagnoses of partial- and full-syndrome anorexia nervosa and bulimia nervosa (referred to as anorexic syndrome and bulimic syndrome.) METHOD: Participants were 157 females who were studied initially in the 7th-10th grades (ages 12-16) and followed-up 2 and 8 years later in middle adolescence (ages 14-18) and young adulthood (ages 20-24), respectively. A telephone interview to determine lifetime history of anorexic and bulimic syndromes was conducted in young adulthood. RESULTS: In multivariate analyses controlling for initial eating symptoms, initial perfectionism and low body weight predicted young adult onset of anorexic syndrome, and initial negative emotion predicted young adult onset of bulimic syndrome. DISCUSSION: Our findings suggest that adolescent girls who are initially thin and also adhere to perfectionistic standards may be at risk for developing anorexic syndrome. For bulimia, negative affect may contribute to the development of the binge-purge cycle.  相似文献   
998.
OBJECTIVE: To examine in two separate studies the effects of replacing dietary fat with Olestra on body composition and weight change in healthy young men and women. METHODS: Ten healthy, lean young men participated in Study One that was a 22-day single blind, within-subject design. After a control diet (40% fat) for eight days Study One subjects received an Olestra-substituted diet (31% metabolizable fat) for 14 days. Study Two was a randomized parallel-arm clinical trial with 15 healthy, lean and overweight young women. These subjects were randomly assigned to receive a control diet (40% fat), an Olestra-containing diet (31% metabolizable fat) or a reduced-fat diet (31% fat) for 10 weeks. All foods were provided to the subjects, and energy intakes were not restricted. The primary endpoint in both studies was change from baseline in body weight. In Study Two, body composition was measured by dual energy x-ray absorptiometry. In both studies, food intake and nutrient compensation were assessed. RESULTS: In Study One fat substitution by Olestra resulted in a significant 1.7 kg weight loss from baseline. In Study Two, change in body weight and body fat from baseline were statistically significant in all groups, but the group with Olestra lost significantly more weight from baseline (-5.0 kg) than the other two groups. In Study One there was partial compensation for the decreased energy intake, while in Study Two, compensation was seen only for those on the reduced-fat diet. CONCLUSION: Replacement of 1/3 of dietary fat with Olestra in periods of up to 10 weeks results in weight loss in men and women.  相似文献   
999.
The effects of insulin on tumor oxygenation, perfusion, oxygen consumption,and radiation sensitivity were studied on two different mouse tumor models (TLT, a liver tumor, and FSAII, a fibrosarcoma). Anesthetized mice were infused with insulin i.v. at a rate of 16 milliUnits/kg/min for 25 min. Local tumor oxygenation measurements were carried out using two independent techniques: electron paramagnetic resonance oximetry and a fiber-optic device (OxyLite). Two complementary techniques were also used to assess the blood flow inside the tumor: a laser Doppler system (OxyFlo) and contrast-enhanced magnetic resonance imaging. The oxygen consumption rate of tumor cells after in vivo insulin infusion was measured using high frequency electron paramagnetic resonance oximetry. To know if insulin was able to enhance radiation-induced tumor regrowth delay, tumor-bearing mice were treated with 16 Gy of 250 kV radiation dose after insulin infusion. We provide evidence that insulin increases the local pressure of oxygen of tumors (from 0-3 mm Hg to 8-11 mm Hg) as well as the tumor response to irradiation (increasing regrowth delay by a factor of 2.11). We found that the insulin-induced increase of tumor pressure of oxygen: (a) is not caused by an increase in the tumor blood flow, which is even decreased after insulin infusion; (b) is because of a decrease in the tumor cell oxygen consumption (in vivo insulin consumed oxygen three times slower than control cells); and (c) is inhibited by a nitric oxide (NO) synthase inhibitor, Nomega-nitro-L-arginine methyl ester, when injected i.p. at 15 micromol/kg(-1), 1 h before insulin infusion. We demonstrate by immunoblotting that the NO pathway involves a phosphorylation of endothelial NO synthase and showed a concomitant increase in the cyclic GMP tumor level. These findings provide unique insights into biological processes in tumors, new possible management for treating cancer patients, and raise major questions about the role of insulin secretion (fasting status and diabetes) in the clinical response of tumors to radiation therapy.  相似文献   
1000.
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