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排序方式: 共有798条查询结果,搜索用时 170 毫秒
91.
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93.
L L Otto-Salaj R Nadon I P Hoyt P A Register J F Kihlstrom 《The International journal of clinical and experimental hypnosis》1992,40(1):12-20
In an investigation of hemispheric activity during hypnosis, a total of 1269 Ss received hypnotizability scales containing suggestions targeting the left or right side of the body. There were no consistent differences in response strength on the left compared to the right side. Nor were there differences in hypnotizability between right- and left-handed (and ambidextrous) Ss, or between Ss who sat on the left versus right side of the testing room. Definitive evidence of lateralized cerebral activity associated with hypnosis and hypnotizability can only come from direct neuropsychological, electrocortical, or brain-imaging investigations. 相似文献
94.
CT guidance for percutaneous gastrostomy and gastroenterostomy 总被引:2,自引:0,他引:2
Sanchez RB; vanSonnenberg E; D'Agostino HB; Goodacre BW; Moyers P; Casola G 《Radiology》1992,184(1):201
95.
Wood CE Sitruk-Ware RL Tsong YY Register TC Lees CJ Cline JM 《Menopause (New York, N.Y.)》2007,14(4):639-647
OBJECTIVE: To evaluate the effects of oral estradiol given with either oral or intravaginal micronized progesterone (P4) on risk biomarkers for breast cancer in a postmenopausal monkey model. DESIGN: This experiment was a two-way crossover study in which 20 ovariectomized adult female cynomolgus macaques were treated (in equivalent doses for women) with oral estradiol (1 mg/d) + oral micronized P4 (200 mg/d) or intravaginal P4 delivered by Silastic rings (6- to 10-mg/d release rate). Hormone treatments lasted 2 months and were separated by a 1-month washout period. The primary outcome measure was breast epithelial proliferation. RESULTS: Serum P4 concentrations were significantly greater in subjects receiving oral P4 (10.9 ng/mL) compared with intravaginal P4 (3.8 ng/mL) at 2 to 3 hours after oral dosing (P<0.0001) but not at 24 to 28 hours after oral dosing (2.9 ng/mL for oral P4 vs 3.2 ng/mL for intravaginal P4 at 2 months, P=0.19). Serum estradiol concentrations were significantly lower after oral P4 than after intravaginal P4 (P<0.05 for all time points). Oral P4 resulted in significantly decreased body weight (-2.5%) compared with intravaginal P4 (+3.6%) (P=0.0001). Markers of breast proliferation, sex steroid receptor expression, and endometrial area did not differ significantly between oral P4 and intravaginal P4 treatments (P>0.1 for all). CONCLUSIONS: Despite different pharmacodynamic profiles, oral and intravaginal P4 had similar effects on biomarkers in the postmenopausal breast. 相似文献
96.
Miralles P Berenguer J Ribera JM Rubio R Mahillo B Téllez MJ Lacruz J Valencia E Santos J Rodríguez-Arrondo F Pintado V;Grupo de Estudio del SIDA Register of Systemic AIDS-Related Lymphomas 《Journal of acquired immune deficiency syndromes (1999)》2007,44(2):167-173
OBJECTIVES: To assess complete remission (CR) and survival in patients with systemic AIDS-related non-Hodgkin lymphoma (ARL) receiving highly active antiretroviral therapy (HAART). METHODS: We analyzed the Grupo de Estudio del SIDA register of systemic ARL, which started in Jan 1994, to collect cases diagnosed at 15 institutions prospectively and with active follow-up every 6 months. The date of censorship for this study was March 2005. RESULTS: During the study period, 210 consecutive patients were diagnosed with ARL, with a median age 39 of years, 75.7% of whom were male, and with a median baseline CD4 count of 160 cells/microL. Histologic subtypes were diffuse large B-cell lymphoma (DLCL; n = 153 [72.9%]), Burkitt and atypical Burkitt/Burkitt-like lymphoma (BL; n = 40 [19.0%]), T-cell lymphoma (TC; n = 8 [3.8%]), and miscellaneous (n = 9 [4.3%]). Chemotherapy with or without other modalities was administered to 186 (88.6%) patients. In an intent-to-treat analysis of 184 patients who received at least 1 chemotherapy course with adequate follow-up to assess their response, 119 (64.7%) achieved CR, and the median length of survival (Kaplan-Meier analysis) was 52 months (95% confidence interval [CI]: 23 to 82 months). Factors independently associated with CR were histologic subtype and International Prognostic Index (IPI) score. Factors independently associated with improved overall length of survival (OS) were CR, low IPI score, and histologic subtype. The single factor independently associated with disease-free survival was Ann Arbor stage. CONCLUSIONS: In patients with ARL treated with HAART, CR was associated exclusively with tumor-related factors. The CR rate was poorer in patients with BL and TC subtypes and was inversely correlated with IPI score. OS was independently associated with CR, IPI score, and the histologic subtype. 相似文献
97.
Immune response in mice and swine to DNA vaccines derived from the Pasteurella multocida toxin gene 总被引:2,自引:0,他引:2
DNA vaccines were constructed with either a 5'-truncated or full-length, genetically detoxified toxin gene from Pasteurella multocida and two different DNA vaccine vectors, distinguished by the presence or absence of a secretion signal sequence. Optimal PMT-specific antibody responses and spleen cell secretion of interferon-gamma following immunization of mice were achieved with pMM4, the construct containing a signal sequence and encoding the entire toxin. Antibody responses were also induced in pigs immunized with pMM4 and levels increased significantly following booster injections and experimental infection with P. multocida. Significantly increased expression of interferon-gamma was detected in only a small subset of pMM4-immunized pigs. This report documents, for the first time, the ability of a DNA vaccine to elicit immune responses to the P. multocida toxin in both mice and swine. 相似文献
98.
Park S Kelly R Kahn JN Robles J Hsu MJ Register E Li W Vyas V Fan H Abruzzo G Flattery A Gill C Chrebet G Parent SA Kurtz M Teppler H Douglas CM Perlin DS 《Antimicrobial agents and chemotherapy》2005,49(8):3264-3273
An association between reduced susceptibility to echinocandins and changes in the 1,3-beta-d-glucan synthase (GS) subunit Fks1p was investigated. Specific mutations in fks1 genes from Saccharomyces cerevisiae and Candida albicans mutants are described that are necessary and sufficient for reduced susceptibility to the echinocandin drug caspofungin. One group of amino acid changes in ScFks1p, ScFks2p, and CaFks1p defines a conserved region (Phe 641 to Asp 648 of CaFks1p) in the Fks1 family of proteins. The relationship between several of these fks1 mutations and the phenotype of reduced caspofungin susceptibility was confirmed using site-directed mutagenesis or integrative transformation. Glucan synthase activity from these mutants was less susceptible to caspofungin inhibition, and heterozygous and homozygous Cafks1 C. albicans mutants could be distinguished based on the shape of inhibition curves. The C. albicans mutants were less susceptible to caspofungin than wild-type strains in a murine model of disseminated candidiasis. Five Candida isolates with reduced susceptibility to caspofungin were recovered from three patients enrolled in a clinical trial. Four C. albicans strains showed amino acid changes at Ser 645 of CaFks1p, while a single Candida krusei isolate had a deduced R1361G substitution. The clinical C. albicans mutants were less susceptible to caspofungin in the disseminated candidiasis model, and GS inhibition profiles and DNA sequence analyses were consistent with a homozygous fks1 mutation. Our results indicate that substitutions in the Fks1p subunit of GS are sufficient to confer reduced susceptibility to echinocandins in S. cerevisiae and the pathogens C. albicans and C. krusei. 相似文献
99.
Chediak-Higashi gene in humans. I. Impairment of natural - killer function 总被引:3,自引:0,他引:3
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T Haliotis J Roder M Klein J Ortaldo AS Fauci RB Herberman 《The Journal of experimental medicine》1980,151(5):1039-1048
Natural-killer (NK)-cell function was profoundly depressed in donors homozygous for the Chediak-Steinbrinck-Higashi syndrome (C-HS) gene when compared with age- and sex-matched normals. This apparent defect was not simply a result of a delayed response because little cytolysis was evident in kinetics experiments even after 24 h of incubation. NK cells from C-HS donors failed to lyse adherent (MDA, CEM, and Alab) or nonadherent (K562 and Molt-4) tumor cell lines or nontransformed human fetal fibroblasts. Therefore, the apparent C-HS defect was not a result of a shift in target selectivities. In addition, the depressed reactivity did not appear to be a result of suppressor cells or factors because: (a) enriched NK populations (nonadherent lymphocytes bearing receptors for the Fc portion of IgG) from C-HS donors were low in NK-cell function, (b) C-HS mononuclear cells did not inhibit the cytotoxicity of normal cells in coculture experiments, and (c) cells from the C-HS donors remained poorly reactive even after culture for up to 7 d. The nature of the defective NK activity in C-HS patients is not clear but may lie within the lytic mechanism rather than at the level of the recognition structure or population size because the frequency of target-binding cells was normal. In vitro NK activity could be partially restored by interferon treatment. Combined with the results presented in the following paper (4), these observations suggest that the C-HS gene causes a selective immunodeficiency disorder, mainly involving NK cells. This finding, in conjunction with the high incidence of spontaneous possibly malignant, lymphoproliferative disorders in these patients, may have important implications regarding the theory of immune surveillance mediated by NK cells. 相似文献
100.
Macrophage microbicidal activity. Correlation between phagocytosis-associated oxidative metabolism and the killing of candida by macrophages 总被引:29,自引:0,他引:29
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The mechanisms by which macrophages kill ingested microorganisms were explored using Candida albicans and Candida parapsilosis. The results indicate that efficient macrophage candidacidal activity depends upon the generation of oxygen metabolites by the phagocytic cell: (a) peritoneal macrophages from mice infected with bacillus Calmette-Guerin (BCG) or injected intraperitoneally with lipopolysaccharide (LPS) released more superoxide anion (0(2)(-)) during phagocytosis of candida and killed candida better than did resident macrophages; (b) cells of the macrophage-like line J774.1, which released negligible amounts of O(2)(-), could ingest the candida normally but not kill them; (c) killing of candida by resident, LPS- elicited, and BCG-activated macrophages was inhibited by agents that scavenge O(2)(-), hydrogen peroxide (H(2)0(2)), hydroxyl radical (x OH), and singlet oxygen; and (d) all three macrophage types killed C. parapsilosis more effectively than C. albicans, and (7. parapsilosis stimulated a more prompt and vigorous burst of macrophage oxygen consumption and 0(2)(-) release than did C. albicans. Macrophages ingested C. parapsilosis slightly more quickly than C. albicans, but phagocytosis of both strains was equivalent by 60 min of incubation. Although C. albicans contained higher concentrations of the oxygen-metabolite scavengers superoxide dismutase and catalase, neither fungal species scavenged 0(2)(-) or H(2)0(2) effectively; and C. albicans was killed more easily than C. parapsilosis by a xanthine oxidase system that generates primarily H(2)O(2) at pH 7, or 0(2)(-) and x OH at pH 10. Thus, the decreased killing of C. albicans appears to result primarily from the capability of this species to elicit less vigorous stimulation of macrophage oxidative metabolism. This capability may have general relevance to the pathogenicity of microorganisms. 相似文献