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91.
A review of the literature suggests that a common psychobiological process is associated with various altered states of consciousness (ASC) utilized by shamans, meditators, and mediums. However, the shamanic state of consciousness (SSC) can be differentiated physiologically from possession trance states. The psychophysiological literature on different types of trances and on seizure conditions associated with the temporal lobe discharge syndrome is reviewed. On this basis, it is hypothesized that while both the SSC and possession trances involve hippocampal-septal stimulation, the difference between the SSC and the possession states includes the amygdala involvement associated with the latter. This criterion and others establish a basis for differentiating between the terms "shamanic," "shamanistic," and "mediumistic." The physiological concomitants of the SSC make it appear to be both physiologically and psychologically beneficial as well as indicating that it is most likely that there is a genetic component affecting one's ability to enter the SSC and other ASC.  相似文献   
92.
Persistent infections were established in suspension cultures of BHK21/13S cells with both Parana and lymphocytic choriomeningitis viruses. Four generations after infection with either virus, more than 90% of the cells scored as infective centers, with concomitant peaks in extracellular virus yields. In both cultures the synthesis of detectable plaque-forming units (PFU) ceased about the 50th generation postinfection, and this condition was maintained until the 350th cell generation when the cultures were discontinued. The generation time of each culture was identical to that of uninfected parent controls, and at no time were cytopathic effects evident. In spite of the absence of infectivity, over 90% of the cells sampled at various times contained viral antigen demonstrable by immunofluorescence. When either of these persistently infected cell lines was substituted for normal cells in the standard plaque assay, very low efficiencies of plating were observed for homotypic and heterotypic viruses. Plaque formation by several heterologous viruses was virtually unaffected. The mechanism of homotypic plaque exclusion in both cell lines was shown to occur beyond the virion adsorption stage. The original infecting virus genome persisted in both cell lines after standard virus was no longer detectable. This was shown with the lymphocytic choriomeningitis virus-infected cells after storage in liquid nitrogen. After thawing, such cells were found to synthesize standard virus for a brief period. Although the Parana virus-infected cells did not behave this way, the growth medium from these cells would initiate PFU synthesis in normal cells within 36 hr after infection.  相似文献   
93.
94.
Liver homogenates from rats fed tamoxifen (TAM) in the diet were shared among four different laboratories. TAM-DNA adducts were assayed by high pressure liquid chromatography-electrospray tandem mass spectrometry (HPLC-ES-MS/MS), TAM-DNA chemiluminescence immunoassay (TAM-DNA CIA), and (32)P-postlabeling with either thin layer ((32)P-P-TLC) or liquid chromatography ((32)P-P-HPLC) separation. In the first study, rats were fed a diet containing 500 p.p.m. TAM for 2 months, and the values for measurements of the (E)-alpha-(deoxyguanosin-N(2)-yl)-tamoxifen (dG-N(2)-TAM) adduct in replicate rat livers varied by 3.5-fold when quantified using 'in house' TAM-DNA standards, or other approaches where appropriate. In the second study, rats were fed 0, 50, 250 or 500 p.p.m. TAM for 2 months, and TAM-DNA values were quantified using both 'in house' approaches as well as a newly synthesized [N-methyl-(3)H]TAM-DNA standard that was shared among all the participating groups. In the second study, the total TAM-DNA adduct values varied by 2-fold, while values for the dG-N(2)-TAM varied by 2.5-fold. Ratios of dG-N(2)-TAM:(E)-alpha-(deoxyguanosin-N(2)-yl)-N-desmethyltamoxifen (dG-N(2)-N-desmethyl-TAM) in the second study were approximately 1:1 over the range of doses examined. The study demonstrated a remarkably good agreement for TAM-DNA adduct measurements among the diverse methods employed.  相似文献   
95.
Plasma alpha-tocopherol (alpha-T) concentrations, erythrocyte osmotic fragility and detergent sensitivity were measured at 8 week intervals in two 1-year-old male beagle dogs fed a vitamin E-deficient diet (< 0.08 mg per kg alpha-T) and in two control beagles fed the same diet supplemented with vitamin E (> 90 mg per kg alpha-T). Beginning at 24 weeks, dialuric acid haemolysis and spontaneous haemolysis were evaluated also. In the vitamin E-deficient dogs, plasma alpha-T concentrations declined progressively from baseline values of 20.5 and 31.3 micrograms per ml to 0.11 and 0.07 micrograms per ml, respectively, by 90 weeks. The supplemented dogs maintained alpha-T concentrations between 18.3 and 38.4 micrograms per ml. Both dialuric acid haemolysis (R = -0.89) and spontaneous haemolysis (R = -0.91) increased with declining plasma alpha-T concentration. In the dialuric acid haemolysis assay, 50 per cent haemolysis occurred when plasma alpha-T declined to 1.7 micrograms per ml, compared with spontaneous haemolysis in which 50 per cent haemolysis occurred when plasma alpha-T declined to 0.5 micrograms per ml. Osmotic fragility and detergent sensitivity remained unchanged in the vitamin E-deficient dogs throughout the study. Of the four tests, dialuric acid haemolysis was the most sensitive in-vitro assay for vitamin E deficiency in adult dogs.  相似文献   
96.
A computerized questionnaire was used to collect information on the presentation of symptoms in all 125 new patients presenting to one general practitioner in the course of one year who were considered to be suffering clinically significant psychiatric disturbance. Comparison was made between the 73 (58%) patients presenting with psychological symptoms and the 52 (42%) patients presenting with somatic symptoms for which no physical explanation was evident at the time of the consultation. Important differences emerged between the groups. Those patients presenting somatic symptoms had lower scores on the tests of psychiatric distress (indicating severity), fewer individual symptoms and fewer severe symptoms than patients presenting with psychological problems. This group also had statistically significant differences in personality profile and reported significantly fewer social problems. Prognosis for both groups was similar in that patients in both groups were equally likely to have a normal psychiatric distress score after six months. Adequate management of somatizing patients calls for vigilance and for improved detection and negotiating skills. Reviewing the computer results with patients helped them discuss their symptoms and the system allowed the general practitioner not only a clinical assessment of these patients' problems but a measure of psychological, social and personality components.  相似文献   
97.
Transposable elements (TEs) comprise a major component of eukaryotic genomes, and exhibit striking deviations from random distribution across the genomes studied, including humans, flies, nematodes, and plants. Although considerable progress has been made in documenting these patterns, the causes are subject to debate. Here, we use the genome sequence of Arabidopsis thaliana to test for the importance of competing models of natural selection against TE insertions. We show that, despite TE accumulation near the centromeres, recombination does not generally correlate with TE abundance, suggesting that selection against ectopic recombination does not influence TE distribution in A. thaliana. In contrast, a consistent negative correlation between gene density and TE abundance, and a strong under-representation of TE insertions in introns suggest that selection against TE disruption of gene expression is playing a more important role in A. thaliana. High rates of self-fertilization may reduce the importance of recombination rate in genome structuring in inbreeding organisms such as A. thaliana and Caenorhabditis elegans.  相似文献   
98.
Quantitative monitoring of human cytomegalovirus (HCMV) infection is helpful in determining appropriate antiviral management of transplant recipients. Quantitative PCR technologies have demonstrated accuracy in measuring systemic HCMV loads. A total of 298 consecutive whole-blood specimens submitted to the Clinical Virology Laboratory at Vanderbilt University Medical Center from 15 February to 31 October 1999 were included in the study. In addition to a qualitative colorimetric microtiter plate PCR assay (MTP-PCR) and a semiquantitative pp65 antigenemia assay, each specimen was measured for HCMV loads by a quantitative PCR assay performed on an ABI PRISM 7700 Sequence Detection System (TaqMan). Compared to results of the MTP-PCR, the sensitivity, specificity, positive predictive value, and negative predictive value were 70.5, 97.5, 87.8, and 92.8% for the antigenemia assay and were 96.7, 92.0, 75.6, and 99.1% for the TaqMan assay, respectively. There was a high correlation between antigenemia values and HCMV loads as determined by the TaqMan (r = 0.989; P < 0.001). Antigenemia values of 0, 1 to 10, 11 to 100, 101 to 1,000, and over 1,000 positive cells per 2 x 10(5) leukocytes corresponded to median HCMV loads measured by TaqMan of 125, 1,593, 5,713, 16,825, and 5,425,000 copies/ml, respectively. Corresponding to antigenemia values of 1 to 2, 10, and 50 positive cells per 2 x 10(5) leukocytes, HCMV viral loads of 1,000, 4,000, and 10,000 copies/ml are proposed as cutoff points for initiating antiviral therapy in patient groups with high, intermediate, and low risk of CMV diseases.  相似文献   
99.
The normal counterpart of the neoplastic B cells occurring in Burkitt's lymphomas (BL) is an issue of controversial debate. To clarify this matter, a semi-nested primer polymerase chain reaction was performed to amplify the VDJ rearrangements of the immunoglobulin heavy chain (VH) gene of DNA extracts from 10 (8 sporadic and 2 endemic) BL cases. The resulting amplificates were sequenced for comparison with known germ line VH segments. The control cases comprised six cases of B cell chronic lymphocytic leukemia and six cases of mantle cell lymphoma known to display naive nonmutated, ie, pre-germinal center VH configurations; and eight cases of follicular center lymphoma known to display mutated VH genes with signs of a still-ongoing mutation reaction, characteristic for germinal center cells and lymphomas that derive therefrom. The results of this approach revealed that both sporadic and endemic BL express mutated VH genes with a mutation frequency considerably lower (4.9% and 5.4%, respectively) than that observed in follicular center lymphoma (11.8%). In addition, after subcloning the amplificates, sequence analysis revealed no signs of ongoing mutations. These results led us to conclude that the derivation of neoplastic B cells in BL is definitely not from naive, nonmutated pre-germinal center B cells. Instead, our findings support the view that BL cells stem either from early centroblasts that are arrested after an initial hypermutation reaction, or from germinal center B cells that have differentiated in terms of surface immunoglobulin profile and mutation pattern but not in terms of morphology and proliferation toward SIgM+ IgD- memory B cells because of the deregulated c-myc gene expression.  相似文献   
100.
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