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61.
目的:利用组织培养方法快速繁殖成米麻作为种麻,为寻找出一简便可行的快繁天麻种麻的新途径提供理论依据。方法:天麻块茎或茎尖无菌离体培养,米麻块茎诱导培养基为1/2MS+6-BA 1mg/L NAA0.5mg/L+香蕉50mg/L;箭麻茎尖诱导培养基为1/2MS+6-BA2mg/L NAAO.2mg/L。结果:小米麻经50d无菌培养后开始生长出新米麻,70d后原小米麻块茎上生长出多个分枝的新米麻;箭麻茎尖超过140d组织培养,茎尖分化、诱导形成原球茎,超过160d培养原球长大并开花。结论:天麻可以用组织培养方法快速繁殖成米麻作为种麻。  相似文献   
62.
An epidemic amongst recruits who presented with acute viral exudative pleural effusion with lymphocytic pleocytosis is analysed. Histologic and bacteriologic proof of tuberculosis was lacking in majority. Most of them recovered without pleural thickening. Overcrowding, inadequate clothing protection, stress and strain of vigorous recruit training could be important precipitating factors. None reported with parenchymal tuberculosis in two year follow up.KEY WORDS: Pleural effussion, Viral  相似文献   
63.
Analysis of the plasminogen activator activity of the human glomerulus   总被引:3,自引:0,他引:3  
An assay was developed to measure plasminogen activator activity from isolated human glomeruli. Activator was extracted from individual glomeruli with 0.2 M phosphate-buffered saline, pH 7.4 (PBS), containing 0.01% Triton X-100 and quantitated in 125I-fibrin films. Quenching studies using antibodies to tissue plasminogen activator and urokinase revealed that the extracted glomerular plasminogen activator activity contained both tissue plasminogen activator of urokinase. Monoclonal and polyclonal antibodies raised to tissue plasminogen activator demonstrated low-level inhibition of urokinase activity and monoclonal and polyclonal antibodies to urokinase demonstrated low-level inhibition of tissue plasminogen activator activity. The assay should be applicable to the study of glomerular plasminogen activator activity in experimental and human kidney diseases. The detection of antibody cross-reactivity to tissue plasminogen activator and urokinase may be related to the sensitivity of the 125I-fibrin assay and to the structural similarities of these activators.  相似文献   
64.
Cardiac-gated magnetic resonance (MR) imaging was performed in rats to determine the effects of manganese ethylenediaminetetraphosphonate (TP). Ten normal rats received Mn-TP in a dose of 50 mumol/kg through a tail-vein injection. Spin-echo MR images were obtained before and every 10 minutes after Mn-TP injection for 1 hour. Cardiac signal intensity (SI) increased more than 70% after Mn-TP injection and remained nearly unchanged 1 hour after injection. Myocardial T1 was 517 +/- 49 msec in eight control rats and 282 +/- 61 msec (P less than .001) in six rats 81 +/- 0 minutes after injection. Nine rats underwent occlusion of the left anterior descending coronary artery prior to MR imaging. Images were obtained before and 15, 30, and 60 minutes after Mn-TP injection. In normal myocardium, SI increased up to 82% and remained elevated for 1 hour. In ischemic myocardium, SI rose 11%, leading to a marked contrast between the two tissue zones. T1 was also different in the two regions: In normal tissue, it was 206 msec +/- 54; in ischemic tissue, 338 +/- 82 (P less than .001). With T1-weighted MR imaging, Mn-TP showed a potential for delineating the jeopardized area after acute myocardial ischemia.  相似文献   
65.
Summary Contact sensitivity (CS) induced by hapten has been thought to be analogous to delayed-type hypersensitivity, such as the Mantoux reaction, because of outstanding similarities between the two phenomena. It can be suggested that animals with CS respond also to intradermal injection of the conjugate of hapten and protein as well as to epicutaneous application of hapten. However, evidence against this has been reported. In the present experiments, delayed-type skin reaction (DSR) was successfully obtained in JY1 strain guinea pigs sensitized by painting the skin with 2,4-dinitrochlorobenzene using in vitro dinitrophenylated epidermal cell suspension (DNP-EC) as antigen for a delayed intradermal test. The experiment using anti-Ia alloantiserum and complement showed that the elicitation of DSR is due to the presence of Ia-positive cells (presumably Langerhans cells) among DNP-ECs. The delayed intradermal test with the conjugates such as haptenated ECs in the animals with CS is considered to be an experimentally useful way of analysing the antigen in the sensitivity.  相似文献   
66.
This first Australasian randomized trial of 5-methoxy psoralen (5-MOP) PUVA for psoriasis shows, conclusively, less acute side effects than 8-MOP PUVA. Daily addition of oral etretinate to the PUVA regimen (Re-PUVA) produces a valuable reduction in total joules and more so with 5-MOP than with 8-MOP. The clearing phase with 5-MOP Re-PUVA is quicker than with 8-MOP Re-PUVA in skin types 1, 2, and 3 (most Anglo-Saxon-Celtic Australians). Doses, when adapted to total body surface rather than mg/kg, allow superior control of therapy. Emollient creams, tar gels, nonsteroidal scalp applications, etc. allow more patient comfort.  相似文献   
67.
BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease expressed early in life. Disease development is primarily determined by as yet unknown genetic factors, leading to the accumulation of activated T lymphocytes in the skin. OBJECTIVES: To investigate the nature of these T cells. METHODS: T-cell lines could be established from AD skin biopsies, but not from normal skin or AD peripheral blood, when placed in RPMI 1640 medium with 10% human AB serum, antibiotics, and the T-lymphocyte growth factors interleukins 2 and 4. The cell lines were subjected to phenotypic analysis using a fluorescence-activated cell sorter and compared with lymphocytes from AD and normal control peripheral blood. RESULTS: T-cell lines from 22 of 24 consecutive skin biopsies taken from 24 adult patients with AD were established. All cells were T lymphocytes expressing several activation markers. A significant proportion of the lymphocytes had stable expression of a CD4+ CD8+ phenotype (26% +/- 6%; mean +/- SEM). Such double-positive T lymphocytes are normally only seen in the thymus and not in the peripheral immune system. CD4+ CD8+ cells in peripheral blood of the patients (12.5% +/- 3.3%) were also detected. CONCLUSIONS: We suggest that a basic pathophysiological change in AD may be a faulty maturation of the T-lymphocyte system, leading to skin inflammation with CD4+ CD8+ T lymphocytes resembling immature T cells. This is likely to lead to skewing of many immune reactions in the patients.  相似文献   
68.
BACKGROUND: Apoptosis has been proposed to act as an important mechanism for eliminating keratinocytes that have been irreversibly damaged by ultraviolet (UV) irradiation. One way to induce apoptosis in keratinocytes is through activation of the cell surface receptor Fas (CD95), either with the ligand (FasL) or directly with UV radiation. OBJECTIVES: To investigate the regulation of Fas and FasL expression in human skin and the formation of apoptotic cells after in vivo exposure to UVB or long-wave UVA radiation. METHODS: Volunteers were irradiated with either 3 minimal erythema doses (MED) of UVB (n = 6) or 3 MED of long-wave UVA (n = 6) on buttock skin 12, 24 and 72 h before skin punch biopsies were taken. Expression of Fas and FasL was demonstrated by immunohistochemistry on cryostat sections. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated fluorescein-deoxyuridine triphosphate nick-end labelling reaction. RESULTS: In five of six subjects, exposure to UVB radiation resulted in increased homogeneous expression of Fas on epidermal cells, with greatest expression at 24 and 72 h after irradiation. In all subjects, exposure to long-wave UVA resulted in increased homogeneous expression of Fas on epidermal cells, with greatest expression at 12 h after irradiation. In five of six subjects, exposure to UVB radiation resulted in temporarily decreased expression of FasL, but after 72 h the expression of FasL had returned to the preirradiation level. The expression of FasL on epidermal cells after exposure to long-wave UVA showed considerable variation. UVB irradiation was a stronger inducer of epidermal apoptosis than was UVA irradiation. The number of apoptotic epidermal cells did not correlate with expression of Fas or FasL. CONCLUSIONS: In human skin the expression of Fas on epidermal cells increases after in vivo exposure to UVB or long-wave UVA. Exposure to UVB causes a temporary decrease in the expression of FasL on epidermal cells.  相似文献   
69.
The efficacy of lamivudine re-treatment in chronic hepatitis B (CHB) patients who relapse after HBeAg seroconversion with lamivudine has not been investigated. The aim of this study was to evaluate the efficacy of lamivudine re-treatment in relapsed patients. Among 192 patients who had achieved HBeAg seroconversion with lamivudine at a dose of 100 mg/day, 121 patients discontinued lamivudine. Relapse occurred in 49 patients (40.5%). Thirty-three relapsed patients received lamivudine re-treatment for at least 6 months. The mean duration of lamivudine re-treatment was 16 months and the follow-up period was 8.9 months. HBeAg seroconversion was achieved in 23 patients (69.7%). The cumulative HBeAg seroconversion rates at 5, 9, and 12 months were 60, 64, and 67%, respectively. The mean time to HBeAg seroconversion in lamivudine re-treatment was shorter than that in the initial therapy (4.7 months vs. 9.7 months). Viral breakthrough occurred in six (18.2%) patients. All patients with viral breakthrough were accompanied by elevation of serum alanine aminotransferase (ALT) levels. Among 15 patients who discontinued lamivudine re-treatment after HBeAg seroconversion, relapse occurred in six patients (40%). All relapses occurred within 9 months after the discontinuation of lamivudine re-treatment. In conclusion, lamivudine re-treatment in relapsed patients after initial lamivudine therapy had a higher response rate and shorter duration to HBeAg seroconversion than during the initial therapy. However, HBeAg seroconversion induced by lamivudine re-treatment was not durable.  相似文献   
70.
Our previous study suggested that fenofibrate affects obesity and lipid metabolism in a sexually dimorphic manner in part through the differential activation of hepatic peroxisome proliferator-activated receptor alpha (PPARalpha) in male and female C57BL/6J mice. To determine whether fenofibrate reduces body weight gain and adiposity in female sham-operated (Sham) and ovariectomized (OVX) C57BL/6J mice, the effects of fenofibrate on not only body weight, white adipose tissue (WAT) mass, and food intake, but also the expression of both leptin and PPARalpha target genes were measured. Compared to their respective low-fat diet-fed controls, both Sham and OVX mice exhibited increases in body weight and WAT mass when fed a high-fat diet. Fenofibrate treatment decreased body weight gain and WAT mass in OVX, but not in Sham mice. Furthermore, fenofibrate increased the mRNA levels of PPARalpha target genes encoding peroxisomal enzymes involved in fatty acid beta-oxidation, and reduced apolipoprotein C-III (apo C-III) mRNA, all of which were expressed at higher levels in OVX compared to Sham mice. However, leptin mRNA levels were found to positively correlate with WAT mass, and food intake was not changed in either OVX or Sham mice following fenofibrate treatment. These results suggest that fenofibrate differentially regulates body weight and adiposity due in part to differences in PPARalpha activation, but not to differences in leptin production, between female OVX and Sham mice.  相似文献   
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