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51.
OBJECTIVE--To determine the prevalence of behaviour disorders in low birthweight infants. DESIGN--Children of birth weight < or = 2000 g born to mothers resident in Merseyside in 1980-1 assessed using the Rutter parent and teacher behaviour questionnaires and the Conner modification of the Rutter teacher questionnaire. Children attending normal schools were assessed with controls matched for age, sex, and class in school. Children attending special schools were assessed unmatched. SUBJECTS--233 matched case-control pairs attending normal primary schools and 46 unmatched children attending special schools. SETTING--Primary and special schools. MAIN OUTCOME MEASURES--Emotional, conduct, and undifferentiated behaviour disorders and hyperactivity. RESULTS--On the parental questionnaire screen, 36% of the cases and 22% of the controls had a behaviour disorder and on the teacher questionnaire the proportions were 27% and 12% respectively. Hyperactivity was significantly more common among male cases than their controls (21% v 5.0%) but differed little among female cases and controls (9% v 7%). CONCLUSIONS--Improving neonatal survival of low birthweight infants is accompanied by a higher prevalence of behaviour disorders. The long term implications for psychiatric morbidity and other adult disease must be monitored. 相似文献
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Summary Newcastle disease virus (NDV) induces in the human amniotic membrane (HAM) two interferons: a large amount of a heavy component (MW160,000) and a small amount of a light one (MW ranging from 22,000 to 25,000). The crude preparation and the interferon components induce the antiviral state in monkey cells (BSC-1) and in rat embryonic fibroblasts (REF).In this study, HAM interferon is compared to the human interferon produced by white blood cells (WBC). Two fundamental differences are reported between these two types of interferon: (1) HAM interferon induces the antiviral state in REF, while WBC interferon is nearly inactive; (2) antibody produced against WBC interferon in rabbits does not neutralize the antiviral effect of HAM interferon.Because of the fundamental differences observed in their antigenic structure and antiviral action, further study is necessary to investigate in more detail the mode of action of the two types of interferon. 相似文献
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Zaneveld LJ Anderson RA Diao XH Waller DP Chany C Feathergill K Doncel G Cooper MD Herold B 《Fertility and sterility》2002,78(5):1107-1115
OBJECTIVE: To assess the contraceptive properties, antimicrobial activity, and safety of mandelic acid condensation polymer (SAMMA). DESIGN: Experimental study of SAMMA's in vitro and in vivo properties. SETTING: Academic research laboratories. PATIENT(S): Healthy volunteers for semen donation in an academic research environment. INTERVENTION(S): Inhibition of sperm function indicators, conception, sexually transmitted infection-causing pathogens (including HIV), and lactobacilli was evaluated. Safety indicators were studied. MAIN OUTCOME MEASURE(S): Quantitation of SAMMA's effect on microbial infectivity or multiplication and on sperm function in vitro; evaluation of contraceptive efficacy in vivo; assessment of safety in vitro and in vivo. RESULT(S): Mandelic acid condensation polymer is not cytotoxic toward lactobacilli, microbial host cells, and spermatozoa. The compound inhibits hyaluronidase and acrosin, induces sperm acrosomal loss, and is contraceptive in the rabbit model. Mandelic acid condensation polymer prevents infectivity of HIV and herpesviruses 1 and 2 and, to a lesser extent, of Chlamydia trachomatis. It inhibits the multiplication of Neisseria gonorrhoeae. Mandelic acid condensation polymer is not mutagenic, has low acute oral toxicity, and is safe in the rabbit vaginal irritation assay. CONCLUSION(S): Mandelic acid condensation polymer inhibits sperm function, is contraceptive, has broad-spectrum antimicrobial activity, and is highly safe. Further development as a microbicide is warranted. 相似文献
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The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed. 相似文献
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三尖杉树皮粗提取物中的一个新生物碱—高三尖杉酯碱酰胺(homoharringtonamide)的结构,经质谱—质谱分析,初步建议为16。类似的酰胺类生物碱,例如三尖杉碱酰胺(cephalotaxamide,6)、11-羟基三尖杉碱酰胺(11-hydroxycephalotaxamide,9)、三尖杉酯碱酰胺(harfingtonamide,14)或异三尖杉酯碱酰胺(isoharringtonamide,15)也可能存在,后三者(9,14,15)尚未见报道。 相似文献
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Oberyszyn TM; Conti CJ; Ross MS; Oberyszyn AS; Tober KL; Rackoff AI; Robertson FM 《Carcinogenesis》1998,19(3):445-455
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate
adherence of leukocytes to vascular endothelium and the associated ligand,
intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2
integrin proteins to allow transendothelial migration of leukocytes into
sites of inflammation. The present study examines the function of these
proteins in a murine model of acute cutaneous inflammation induced
following topical application of 12-O- tetradecanoylphorbol-13-acetate
(TPA) to the dorsal epidermis of SENCAR mice and in a model of skin
multistage carcinogenesis. At 24 h following topical application of TPA to
the dorsal epidermis of mice, dermal leukocytes expressed higher levels of
beta2 integrin protein compared with the lower levels of beta2 integrin
protein expression by peripheral blood leukocytes. ICAM-1 protein was
localized to epidermal keratinocytes and vascular endothelium in
TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.)
injection of either 50 microg anti-beta2 integrin antibody alone or in
combination with anti-ICAM-1 antibody significantly inhibited both
TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and
myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P
< 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but
had no effect on TPA-induced epidermal hyperplasia. In addition, injection
of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in
combination with anti-beta2 integrin antibody (P < 0.001) significantly
inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8-
OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2
integrin/ICAM-1 adhesion molecules work in concert to regulate migration,
retention and functional activation of leukocytes within the dermis during
TPA-induced skin inflammation and within stromal tissue of papillomas that
form during multi-stage carcinogenesis. Agents that inhibit these
receptor/ligand interactions may be useful in defining the roles of
specific cell populations in cutaneous inflammation and multistage
carcinogenesis and may also have potential as anti-promoting and
anti-progression agents.
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