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排序方式: 共有1678条查询结果,搜索用时 31 毫秒
961.
RF Deicken L Zhou F Corwin S Vinogradov MW Weiner 《Canadian Metallurgical Quarterly》1997,154(5):688-690
OBJECTIVE: The authors measured N-acetylaspartate (a putative neuronal marker), using in vivo proton magnetic resonance spectroscopic imaging (1H-MRSI), in the frontal lobes of schizophrenic patients and normal subjects. METHOD: Frontal lobe 1H-MRSI was performed bilaterally on 24 medicated schizophrenic patients and 15 healthy comparison subjects. Levels of N-acetylaspartate, creatine, and choline were determined. RESULTS: Relative to the comparison group, the patients with schizophrenia demonstrated significantly lower levels of N-acetylaspartate in the left frontal lobe. There was no association between level of N-acetylaspartate and duration of illness or medication dosage. No differences between groups or lateralized asymmetries in choline or creatine were noted. CONCLUSIONS: This preliminary study provides support for decreased N-acetylaspartate in the left frontal lobe in schizophrenia and neuronal dysfunction in this brain region. 相似文献
962.
PROBLEM: To describe pregnant women's perceptions in two specific areas: expectations about prenatal care and satisfaction with prenatal care. METHOD: A focus group technique using a semi-structured interview format. Three focus groups (N = 22) were conducted in the third trimester of pregnancy. Data were transcribed from the taped sessions and studied using content analysis. FINDINGS: Three major dimensions of satisfaction were identified: satisfaction with health care provider(s); satisfaction with support staff; and satisfaction with the prenatal care, including the desire for continuity of provider, clear explanations, and accessible quality care. CONCLUSIONS & IMPLICATIONS FOR NURSING: The provider relationship was identified as having the greatest influence on the women's satisfaction with prenatal care. Satisfaction with prenatal care can be enhanced through positive provider-patient interactions. 相似文献
963.
There are numerous in vitro studies documenting the multiplication of Legionella species in free-living amoebae and other protozoa. It is believed that protozoa serve as host cells for the intracellular replication of certain Legionella species in a variety of environmental settings. This study describes the isolation and characterization of a bacterium initially observed within an amoeba taken from a soil sample. In the laboratory, the bacterium multiplied within and was highly pathogenic for Acanthamoeba polyphaga. Extracellular multiplication was observed on buffered charcoal yeast extract agar but not on a variety of conventional laboratory media. A 16S rRNA gene analysis placed the bacterium within the genus Legionella. Serological studies indicate that it is distinct from previously described species of the genus. This report also describes methods that should prove useful for the isolation and characterization of additional Legionella-like bacteria from free-living amoebae. In addition, the characterization of bacterial pathogens of amoebae has significant implications for understanding the ecology and identification of other unrecognized bacterial pathogens. 相似文献
964.
A national survey was conducted to investigate malpractice litigation at United States child and adolescent psychiatry residency programs between 1981 and 1991. Fourteen percent of the directors of child and adolescent psychiatry reported at least one malpractice claim during this period. The highest percentage of lawsuits reported was in the northeast. Suicide and sexual abuse of latency age patients by other patients accounted for the most litigation. The mean monetary award was $167,000, and the largest award was $500,000 for discharge of a patient who killed his mother. There has been an increase in malpractice litigation during the past 10 years. Risk management strategies should be implemented to address areas of liability in child and adolescent psychiatry training programs. 相似文献
965.
Personality traits are differentially linked to mental disorders: a multitrait-multidiagnosis study of an adolescent birth cohort 总被引:1,自引:0,他引:1
RF Krueger A Caspi TE Moffitt PA Silva R McGee 《Canadian Metallurgical Quarterly》1996,105(3):299-312
We describe a psychoeducational group intervention for family members of persons living with AIDS. The 33 family members were compared with 13 waiting-list controls in order to evaluate the effectiveness of the intervention. We focus on the practice aspects of the intervention, its development and implementation, and our belief that it is an apparently effective approach for helping family members work through the social and emotional aspects of the devastating impact of HIV/AIDS. 相似文献
966.
RF Kropman JA van Oostayen KH Zwinderman GA Lycklama A Nijehold J Schipper W Meinhardt 《Canadian Metallurgical Quarterly》1994,6(3):125-135
In 37 patients 25 to 69 years old (mean age 49.6 years) with suspected 'vasculogenic erectile dysfunction', diagnosed on the basis of repeated negative reactions to intracavernous pharmacological stimulation, duplex Doppler measurements and pharmacocavernosometry were performed in one session under simultaneous pressure registration. A statistically significant difference between patients with and without veno-occlusive dysfunction was found by combining end-diastolic velocity and pressure in time. We conclude that color Doppler scanning in combination with simultaneous pressure registration can predict veno-occlusive dysfunction in 83-95% of the patients. 相似文献
967.
D4 dopamine receptor-mediated signaling events determined in transfected Chinese hamster ovary cells
CL Chio RF Drong DT Riley GS Gill JL Slightom RM Huff 《Canadian Metallurgical Quarterly》1994,269(16):11813-11819
A Chinese hamster ovary (CHO) cell line stably expressing a recombinant human D4 dopamine receptor made from a synthetic gene has been used to determine potential D4-mediated signaling events. We designed and synthesized a modified gene coding for a human D4 receptor with reduced G + C content but unaltered encoded amino acids. Stable expression of this gene was obtained in two cell lines, inducible expression in CHO lacI cells and constitutive expression in HEK293 cells. In CHO lacI cells induced to express D4 receptors but not in uninduced cells, dopamine and quinpirole inhibit forskolin-stimulated cAMP accumulation and potentiate ATP-stimulated [3H]arachidonic acid release through a mechanism that requires protein kinase C but is unaffected by membrane-soluble cAMP analogs. In addition, D4 receptor activation causes an increase in the rate of extracellular acidification measured by microphysiometry. This response is unaffected by protein kinase C down-regulation but is inhibited by removal of extracellular sodium and inhibitors of NaH-1 exchange, suggesting the involvement of a Na+/H+ exchanger. All responses are blocked by clozapine and are sensitive to pertussis toxin. D4 receptors, like other G(i)/G(o)-linked receptors, mediate multiple signaling events, and the pathways activated are similar to those used by D2 and D3 receptors expressed in similar cells. 相似文献
968.
969.
We have previously found that radiation-induced chromosome aberrations (dicentrics) are more numerous in lymphocytes from Alzheimer's disease (AD) patients than in those from age-matched normal individuals (Tobi et al. 1990). To investigate this further, we have examined double-strand breaks (dsb) produced by gamma-irradiation in the DNA of AD and normal lymphocytes by using pulsed-field gel electrophoresis. The percentage of DNA migrating into the gels is an indirect measure of the number of dsb; we have assayed the DNA content of sequential slices of the gel by direct fluorometry and have found that the percentage migrating is dose dependent. Our results show that the level of damage is similar in AD and normal lymphocytes and preliminary assays of the rate of repair suggest that the half-time is also similar, the value being > 1 h. The latter is consistent with the known rate of rejoining of chromosome fragments in interphase lymphocytes (Pantelias and Maillie 1985). The results suggest that at a gross level dsb repair is not impaired in AD cells; however, we cannot exclude the possibility that there is misrepair or non-repair of a small fraction of the dsb, which might account for the greater radiosensitivity of the AD cells. 相似文献
970.
PE Hay DJ Morgan CA Ison SA Bhide M Romney P McKenzie J Pearson RF Lamont D Taylor-Robinson 《Canadian Metallurgical Quarterly》1994,101(12):1048-1053
OBJECTIVE: To determine the longitudinal changes in the incidence of vaginosis in pregnancy. DESIGN: A prospective study of women during pregnancy. SETTING: A District General Hospital in North-West London. SUBJECTS: Seven hundred and eighteen pregnant women attending antenatal clinics. At their first attendance and subsequently, Gram-stained vaginal smears were examined and Mycoplasma hominis and Gardnerella vaginalis were sought by culture. RESULTS: Initially, 87 (12%) women had bacterial vaginosis diagnosed on Gram-stained reading of the vaginal smears. Examination of further smears, obtained from 176 women at 36 weeks of gestation, showed that those whose vaginal flora was normal initially, and who went to term, rarely developed vaginosis (three of 127, 2.4%). Samples were obtained at 36 weeks gestation from 32 women who had bacterial vaginosis initially, and went to term. In almost 50% (15 of 32) of these a normal lactobacillus-dominated flora had regenerated. Thirty-five women (5%) had initial vaginal smears graded as intermediate. From this group, six of the 17 (35%) women from whom samples were obtained at 36 weeks gestation still had flora of an intermediate pattern; 10(59%) now had normal flora and only one (6%) had developed bacterial vaginosis. Women with bacterial vaginosis were more likely to be culture-positive for M. hominis than those with normal flora (34/78 versus 10/563, odds ratio 42.73 (18.9 to 102.3) P < 0.001), or to be culture-positive for G. vaginalis than those with normal flora (35/78 versus 21/563, odds ratio 21.0 (10.75 to 41.2) P < 0.001). CONCLUSION: Pregnant women do not commonly develop bacterial vaginosis after 16 weeks gestation, and if present, it remits spontaneously in approximately half of those who reach term. As bacterial vaginosis is associated with increased rates of second trimester miscarriage and preterm delivery, any treatment aimed at its eradication in pregnancy should be given no later than the beginning of the second trimester of pregnancy. 相似文献