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31.
The effect of nitrogen and carbon sources on growth and diosgenin production was studied with DIOSCOREA DELTOIDEA cells which were grown under defined conditions in a chemostat, and transferred to batch cultures. Both ammonium and nitrate nitrogen were required for growth and steroid production; diosgenin production was maximal at higher amounts of nitrogen. The nature and concentration of the carbon source (sugar) had marked effects on diosgenin production. A maximal amount of diosgenin (3.8% of dry wt.) was produced on sucrose (15 g/liter) after 21 days of growth in a batch culture. 相似文献
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This paper reports the kinetics of growth and diosgenin production in batch cultures, and the application of the continuous culture (chemostat) technique to DIOSCOREA DELTOIDEA cells. In batch cultures, biomass production was dependent on the concentration (up to 60 g/liter) of the carbon source (sucrose); the cellular yield value obtained was 0.4 g cell dry wt/g sucrose utilized. Diosgenin was synthesized only after growth had ceased; its synthesis proceeded for about 18 days and a concentration of 1.8% (of cell dry wt.) was obtained. D. DELTOIDEA cells were grown at steady state conditions, at a constant growth rate in a chemostat. Only small amounts of diosgenin were produced by growing cells in the chemostat. 相似文献
33.
Substances such as alcohol, cocaine, amphetamine, and cannabis can produce psychotic reactions in individuals who are otherwise free of serious mental illness. However, persons with primary psychotic disorders, such as schizophrenia and bipolar disorder, who use these substances often present for treatment with signs and symptoms similar to those whose psychosis resulted from the use of drugs alone. While it is often difficult to distinguish substance-induced from primary psychoses, especially early in the course of treatment, this differential diagnosis has important implications for treatment planning. To help clinicians distinguish these two types of presentations, the authors first review the types of psychotic symptoms that can co-occur with substance use. They discuss the prevalence and patterns of substance use that have been found in patients with schizophrenia and other primary psychotic disorders and review the negative outcomes associated with substance use in this population. The prevalence of and types of symptoms and problems associated with psychotic symptoms that occur as a result of substance use alone are also reviewed. The authors describe assessment procedures for differentiating substance-induced and primary psychotic disorders. They stress the importance of accurately establishing the temporal relationship between the substance use and the onset and continuation of psychotic symptoms in making a differential diagnosis, as well as the importance of being familiar with the types of psychological symptoms that can occur with specific substances. The authors review the utility and limitations of a number of diagnostic instruments for assessing patients with co-occurring psychosis and substance use problems, including The Addiction Severity Index, The Michigan Alcohol Screening Test, and diagnostic interviews such as the Schedule for Affective Disorders and Schizophrenia and the Structured Clinical Interview for DSM. They then discuss the Psychiatric Research Interview for Substance and Mental Disorders (PRISM), an instrument that has been developed to address the lack of a diagnostic interview that is suitable for assessing the comorbidity of substance use and psychiatric disorders. The article concludes with a discussion of the importance of an appropriate match between diagnosis and treatment and the current state of our knowledge concerning the most appropriate types of treatment interventions for patients with substance-induced psychosis and those with dual diagnoses. 相似文献
34.
Y. Tal L. Even A. Kugelman D. Hardoff I. Srugo M. Jaffe 《European journal of pediatrics》1997,156(6):457-459
The objective of the study was to evaluate the significance of rigor as a predictor of bacterial infection in hospitalized
febrile infants and children. One hundred febrile children with rigor were studied and compared to 334 febrile matched controls
without rigor. All underwent clinical evaluation and appropriate laboratory investigations. The patients were then divided
into “bacterial” and “non bacterial” infection groups, as defined in the text. It was demonstrated that 66% of the patients
with rigor belonged to the bacterial infection group versus 50% in the non-rigor group (P< 0.005). There was a significantly greater yield of positive blood cultures in the patients with rigor (P < 0.04), especially those over the age of 1 year (P < 0.015). The only laboratory examination of potential value as a predictor of bacterial infection in children with rigor was the
band count. An absolute band count of more than 1500/mm was significantly more frequent in the rigor group (P < 0.003), and the combination of a rigor and band count of more than 1500 increased the relative risk for a bacterial infection by
a factor of 1.35. These data demonstrate that rigor in hospitalized febrile infants or children significantly increase the
likelihood of bacterial infection.
Conclusion Although the absence of rigors in febrile children does not exclude bacterial aetiology, their presence significantly increases
the probability of an infection requiring appropriate workup and a readier institution of antibiotic therapy.
Received: 7 June 1996 / Accepted: 15 November 1996 相似文献
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Brian J. Soher William E. Wu Assaf Tal Pippa Storey Ke Zhang James S. Babb Ivan I. Kirov Yvonne W. Lui Oded Gonen 《NMR in biomedicine》2014,27(11):1275-1284
Concentration of the neuronal marker, N‐acetylaspartate (NAA), a quantitative metric for the health and density of neurons, is currently obtained by integration of the manually defined peak in whole‐head proton (1H)‐MRS. Our goal was to develop a full spectral modeling approach for the automatic estimation of the whole‐brain NAA concentration (WBNAA) and to compare the performance of this approach with a manual frequency‐range peak integration approach previously employed. MRI and whole‐head 1H‐MRS from 18 healthy young adults were examined. Non‐localized, whole‐head 1H‐MRS obtained at 3 T yielded the NAA peak area through both manually defined frequency‐range integration and the new, full spectral simulation. The NAA peak area was converted into an absolute amount with phantom replacement and normalized for brain volume (segmented from T1‐weighted MRI) to yield WBNAA. A paired‐sample t test was used to compare the means of the WBNAA paradigms and a likelihood ratio test used to compare their coefficients of variation. While the between‐subject WBNAA means were nearly identical (12.8 ± 2.5 mm for integration, 12.8 ± 1.4 mm for spectral modeling), the latter's standard deviation was significantly smaller (by ~50%, p = 0.026). The within‐subject variability was 11.7% (±1.3 mm ) for integration versus 7.0% (±0.8 mm ) for spectral modeling, i.e., a 40% improvement. The (quantifiable) quality of the modeling approach was high, as reflected by Cramer–Rao lower bounds below 0.1% and vanishingly small (experimental ‐ fitted) residuals. Modeling of the whole‐head 1H‐MRS increases WBNAA quantification reliability by reducing its variability, its susceptibility to operator bias and baseline roll, and by providing quality‐control feedback. Together, these enhance the usefulness of the technique for monitoring the diffuse progression and treatment response of neurological disorders. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
38.
Wolf Bat-Chen Tal Golan Irena Peri Zvi Ludmer Betty Schwartz 《Nutrition and cancer》2013,65(7):947-957
Allicin (diallyl thiosulfinate) is the best-known biologically active component in freshly crushed garlic extract. We developed a novel, simple method to isolate active allicin, which yielded a stable compound in aqueous solution amenable for use in in vitro and in vivo studies. We focused on the in vitro effects of allicin on cell proliferation of colon cancer cell lines HCT-116, LS174T, HT-29, and Caco-2 and assessed the underlying mechanisms. This allicin preparation exerted a time- and dose-dependent cytostatic effect on these cells at concentrations ranging from 6.2 to 310 μM. Treatment with allicin resulted in HCT-116 apoptotic cell death as demonstrated by enhanced hypodiploid DNA content, decreased levels of B-cell non-Hodgkin lymphoma-2 (Bcl-2), increased levels of bax and increased capability of releasing cytochrome c from mitochondria to the cytosol. Allicin also induced translocation of NF-E2-related factor-2 (Nrf2) to the nuclei of HCT-116 cells. Luciferase reporter gene assay showed that allicin induces Nrf2-mediated luciferase transactivation activity. SiRNA knock down of Nrf2 significantly affected the capacity of allicin to inhibit HCT-116 proliferation. These results suggest that Nrf2 mediates the allicin-induced apoptotic death of colon cancer cells. 相似文献
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