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OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
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The authors describe the design and implementation of a large multiethnic cohort established to study diet and cancer in the United States. They detail the source of the subjects, sample size, questionnaire development, pilot work, and approaches to future analyses. The cohort consists of 215,251 adult men and women (age 45-75 years at baseline) living in Hawaii and in California (primarily Los Angeles County) with the following ethnic distribution: African-American (16.3%), Latino (22.0%), Japanese-American (26.4%), Native Hawaiian (6.5%), White (22.9%), and other ancestry (5.8%). From 1993 to 1996, participants entered the cohort by completing a 26-page, self-administered mail questionnaire that elicited a quantitative food frequency history, along with demographic and other information. Response rates ranged from 20% in Latinos to 49% in Japanese-Americans. As expected, both within and among ethnic groups, the questionnaire data show substantial variations in dietary intakes (nutrients as well as foods) and in the distributions of non-dietary risk factors (including smoking, alcohol consumption, obesity, and physical activity). When compared with corresponding ethnic-specific cancer incidence rates, the findings provide tentative support for several current dietary hypotheses. As sufficient numbers of cancer cases are identified through surveillance of the cohort, dietary and other hypotheses will be tested in prospective analyses.  相似文献   
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Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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In the studies of complement fixation described in this paper, the antigens were prepared from (a) normal monkey red cells, (b) parasitized red cells of monkeys dying with Plasmodium knowlesi infection, (c) the spleens of monkeys dying with Plasmodium knowlesi infection; the sera came from (a) normal human beings, (b) patients with syphilis, (c) patients with paresis who were receiving malaria therapy with Plasmodium knowlesi, Plasmodium vivax, or Plasmodium falciparum, and (d) patients with malaria alone. The malarial antigens gave negative complement fixation reactions with 70 to 80 per cent of the luetic and normal sera and weak or doubtful reactions with the remaining 20 to 30 per cent. With the exception of one antigen prepared from spleen, there was no evidence that the malarial antigens were more reactive with Wassermann-positive than with Wassermann-negative sera. Some human sera give weak complement fixation with antigens prepared from normal monkey erythrocytes, and the percentage of these positive reactions is slightly higher with malarial sera than with normal or luetic sera. The most sensitive and specific malarial antigen was prepared from dried parasitized red cells by extraction with saline, freezing, and thawing. This P. knowlesi antigen gives strong complement fixation with malarial sera from human beings infected with P. knowlesi, P. vivax, or P. falciparum. The titer of complement-fixing antibodies reaches a maximum about 1 month after the beginning of the acute infection. At this time all of the P. knowlesi sera tested were positive. After 4 months the reaction diminishes rapidly in titer but may remain positive for 12 months or longer. With P. knowlesi infections in man, the complement fixation reaction remains positive for some time after the infection has apparently disappeared as judged by daily smears and inoculation of monkeys with the blood. The complement fixation reaction in malaria is group-specific rather than species-specific. Sera from patients infected with P. vivax or P. falciparum react in the same way with the P. knowlesi antigen as the homologous sera. Absorption of malarial human sera with normal monkey erythrocytes does not remove the immune bodies which fix complement with malarial antigens.  相似文献   
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