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71.
72.
3例前列腺癌施行双侧睾丸节除术后2-12周的患,每天肌注苯甲酸雌二醇1mg,d。治疗前后分别每10min采血一次,作7h LH脉冲分析。结果表明,3例患平均血清LH水平分别由177.58±3.20,138.30±5.83和145.88±3.82IU/LGHBTGC 174.90±7.60,132.02±5.77和142.80±3.65IU/L(P均<0.01),但LH脉冲幅度和频率无明显变化(  相似文献   
73.
Summary To characterize the pineal response to pyridoxine, plasma melatonin was measured in one hundred and twenty children 3 hours after vitamin B6 administration. The children, aged between 1.5 and 8 years, were divided in four groups as follows: a) control day group, grouping 27 children sampled at 9:00 and at 12:00; b) control night group, grouping 29 children sampled at 21:00 and at 24:00; c) pyridoxine day group, grouping 30 children sampled at 9:00, then intravenously (i.v.) injected with 3mg/kg of pyridoxine, and sampled at 12:00; and d) pyridoxine night group, grouping 34 children sampled at 21:00, i.v. injected with 3mg/kg of pyridoxine, and sampled at 24:00. Melatonin concentration was measured by radioimmuno assay. The data obtained showed a significant increase in melatonin levels after pyridoxine administration in the pyridoxine night group (39.87 ± 8.02pg/ml basal vs 88.45 ± 9.21 pg/ml after pyridoxine, p < 0.001). The other groups did not showed significant differences in melatonin concentrations. Statistical analysis shows that the administration of pyridoxine during the nocturnal hours represents a stimulating factor to increase the pineal production of melatonin in children.  相似文献   
74.
This report describes the laparoscopic features of two patients with serosal eosinophilic gastroenteritis. In one case only hyperemia of the peritoneal serosa was found. In the other the laparoscopic picture resembled peritoneal carcinomatosis. We show that laparoscopy and peritoneal biopsy may permit diagnosis of the disease without the need for laparotomy.  相似文献   
75.
Immunologic methods have been developed for the determinationof benzo(a)pyrene (BP)-protein adducts and validated in animalstreated with (3H)BP. A previously developed antibody, 8E11,which recongnizes 7ß, 8-dihydroxy-9, 10-epoxy-7, 8,9, 10tetrahydrobenzo(a)pyrene (BPDE-I)-modified DNA or proteinas well as BPDE-I- tetraols, was used. The sensitivity of theassay was increased by enzymatic digestion of the modified proteinwith insoluble protease into peptides and amino acids beforeanalysis. In a competitive enzymelinked immunosorbent assay(ELISA) with digested BPDE-I-modified bovine serum albumin,50% inhibition occured at 400 fmol of adduct compared to 1450fmol for the nondigested albumin. Analysis of globin (Gb) isolatedfrom animals treated in vivo with 0.3–3 mg (3H)BP indicatedthat the ELISA could detect 90–100% of the adducts determinedby radioactivity. Levels of adducts in lung and liver DNA andserum albumin were correlated with the levels of Gb adducts.Of the total radioactivity associated with hemoglobin, only10% was from Gb while {small tilde}80% was from the heme fractionand the remainder from free BP metabolites. Significant cross-reactivityof antibody 8E11 was found with several BP-diols and phenols,suggesting that the immunoassay will not only be specific forBPDE-I adducts but will also detect adducts of other BP metabolitesas well as other aromatic hydrocarbon diol epoxides. An immunoaffinitycolumn of antibody 8E11 coupled to Sepharose 4B was used toisolate modified peptides from the digested Gb. About 65% ofthe applied radioactivity was retained on the column. Between1 and 2 mg of non-modified digested Gb could be added to thesample without interfering with binding of adducts. Proteindigestion and immunoaffinity chromatography should be usefulfor the measurement of protein adducts in biomonitoring studies.  相似文献   
76.
Infection of the oral mucous membrane is frequent in patients with removable prostheses, either totally of partially, and particularly when the prostheses is palatal. The principal etiological factor causing the infection is accepted to be "Candidas" aided by the presence of plaque bacteria (in patients with poor oral hygiene care), and a poor fit of the prostheses to the soft tissues. Treatment of the infection must proceed in the following order: a) use of effective medication against oral fungus such as Nystatin or Ketoconazole. b) Meticulous oral hygiene care in the mucous membrane as well as in the prostheses, but using the prostheses as little as possible during the treatment period. c) A total cure of the infection (denture stomatitis) before proceeding to the next phase of the treatment. d) Determination of the adjustment and occlusion of the prostheses in order to determine those areas of the prostheses which need to be refilled because of maladjustment of the prostheses to the soft tissues of the patient.  相似文献   
77.
Mu¨ller  Kristin  Tidona  Christian A.  Bahr  Udo  Darai  Gholamreza 《Virus genes》1998,17(3):243-258
The thymidylate synthase (TS, EC 2.1.1.45) is essential for the de novo synthesis of dTMP in pro- and eucaryotic organisms. Consequently it plays a major role in the replication of the DNA genome of a cell or a DNA virus. The gene encoding the TS of Chilo iridescent virus (CIV) was identified by nucleotide sequence analysis of the viral genome and was mapped within the EcoRI CIV DNA fragments G and R. Computer assisted analysis of the DNA nucleotide sequence between the genome coordinates 0.482 and 0.489 revealed an open reading frame (ORF) of 885 nucleotides. This ORF was found to encode a polypeptide of 295 amino acid residues (33.9 kDa) that showed significant homologies to known TS of different species including mammals, plants, fungi, protozoa, bacteria, and DNA viruses. The highest amino acid homologies were found between the CIV-TS and the TS of herpesvirus ateles (54.0%), Saccharomyces cerevisiae (51.8%), herpesvirus saimiri (51.0%), rhesus monkey rhadinovirus (50.7%), mouse (50.5%), rat (50.2%), varicella-zoster virus (50.2%), equine herpesvirus 2 (50.0%), and the human TS (48.4%). The CIV-TS contains six amino acid domains that are highly conserved in the TS of other species. Within these domains the major amino acid residues are present for which a functional role has been reported. The CIV-TS was found to be more closely related to the TS of eucaryotes than to the TS of procaryotes indicating the phylogenetic origin of the CIV-TS gene. The identification of a TS gene in the genome of CIV is the first report of a viral TS that is not encoded by a herpesvirus or a bacteriophage.  相似文献   
78.
The localization of catecholamines in the brain of the Senegalese sole was determined by immunohistochemical techniques using antibodies against tyrosine hydroxylase. Although the general pattern of distribution of catecholamines is consistent with that reported in other teleosts, some remarkable differences are observed. The most rostral tyrosine hydroxylase immunoreactive (TH-ir) cells were identified in the olfactory bulbs, in which a clear asymmetry in the number and location of TH-ir perikarya and fibers was observed. The number of TH-ir cells is manifestly higher in the right olfactory bulb, especially in the internal cell layer. TH-ir fibers are also much more abundant in the right bulb, principally in the glomerular and internal cell layers. Other TH-ir cell masses were identified in the ventral telencephalon, preoptic area, caudoventral hypothalamus, posterior tuberculum, synencephalon, isthmic region and rhombencephalon. Surprisingly, no ir cell bodies were identified in the ventromedial thalamic nucleus, which exhibits a large number of TH-ir cells in other teleosts. The presence of TH-ir fibers in the brain of sole is particularly evident within and around the nuclei in which immunoreactive cells are found. However, other zones such as the dorsal telencephalon, posterior commissure, optic tectum, torus semicircularis, reticular formation or inferior olive also displayed TH-ir fibers. TH-ir axons also enter the infundibulum, reaching the proximal pars distalis of the adenohypophysis. The distribution of TH-ir cells and fibers is compared with that observed in other teleosts and is discussed in a comparative context.  相似文献   
79.
We evaluated phenotypic and functional parameters of immune restoration of 27 HIV-infected patients on highly active antiretroviral therapy (HAART) (HIV-cases) with HIV-RNA levels below detectable limits at least during 18 months, and CD4+ cell per microliter higher than 500 at the moment of the study and lower than 300 anytime before. These patients were compared with 11 HIV-controls that never had less than 500 CD4+ cell per microliter and 20 healthy-controls (HIV seronegative subjects) in a cross-sectional study. HIV-cases had lower counts of naïve CD4+ than HIV-controls and healthy-controls. HIV-patients (both HIV-cases and HIV-controls) showed higher values of naïve and memory CD8+ counts than healthy-controls. TREC-bearing cell levels were significantly lower in HIV-cases than in healthy-controls. Peripheral blood mononuclear cells (PBMC) cultures, HIV-cases had lower values in proliferation to streptokinase (SK) and tetanus toxin (TT) than in healthy-controls. HIV-cases had lower IFN-γ and higher IL-5 production with pokeweed than healthy-controls (P < 0.01). However, IL-5 production of HIV-cases after TT stimulation was lower than in HIV-controls and healthy-controls. Total IgG and IgG1 levels were significantly higher in HIV-cases than in HIV-controls and healthy-controls. Also, IgM levels were significantly higher in HIV-cases than in healthy-controls. Nevertheless, IgG2 levels were significantly lower in HIV-cases and HIV-controls than in healthy-controls. The levels of specific Igs antipneumococcal capsular polysaccharide and TT were significantly lower in HIV-cases than in healthy-controls. HIV-patients with a previous state of severe-moderate immunosuppression normalizing their CD4+ counts have a incomplete immune reconstitution after HAART. Long-term consequences of this subclinical immune deficiency remain to be determined.  相似文献   
80.
健康Wister雄性大鼠连续 6周腹腔内注射D 半乳糖 ,双侧海马内注射Aβ1-40 造成老年痴呆 (AD)模型。以Y 型迷宫实验检测大鼠的学习记忆行为 ,测定大脑皮层脂褐素含量以及海马线粒体膜流动性、SOD活性、MDA含量 ,电镜观察海马超微结构 ,了解观察褪黑素及红景天素对老年性痴呆模型大鼠的治疗作用。结果显示 ,褪黑素、红景天素均能显著改善痴呆大鼠的学习记忆障碍 ,使大鼠在Y 型迷宫中的训练次数减少 ,对照组 (C组 )、痴呆组 (D组 )、红景天治疗组 (R)组、褪黑素治疗组 (M组 )及联合治疗组 (RM组 )达到学会标准的训练次数分别是 2 7 92± 7 2 9,39 14± 12 35 ,2 8 15± 10 34,2 9 78± 15 74和 2 6 71± 14 70 ,明显逆转痴呆大鼠海马SOD活性的代偿性升高 (R组、M组、RM组中SOD分别降低 4 3 8%、6 1 2 %、5 8 2 % )、减少MDA含量及皮层脂褐素含量 (R组、M组和RM组中MDA分别降低 2 5 9%、2 9 6 %、5 8 5 % ;脂褐素含量减少百分数分别为 36 %、32 %和 5 2 % ) ,防止海马神经元的变性及凋亡。结果提示 ,褪黑素、红景天素治疗后的大鼠与痴呆组相比 ,行为障碍明显改善 ,自由基含量显著下降 ,海马锥体细胞的变性和凋亡现象明显好转。提示两种药物对AD模型大鼠均有一定的防治作用 ,但两者的协同效果不明显  相似文献   
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