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101.
Diets high in fat or iron have been associated with an increased risk for development of colon cancer. These two dietary factors are known to decrease manganese superoxide dismutase (MnSOD) activity in colonic mucosa. MnSOD is an antioxidant enzyme that protects mitochondria from oxygen radical damage. MnSOD has tumour suppressive activity and is absent or decreased in most tumours, including those from the colon. This study was designed to determine the effects of high dietary lipid and iron levels on MnSOD activity during the early weeks of colon carcinogenesis. Male Fischer-344 rats were fed 20% lipid diets of either corn oil or menhaden oil containing adequate iron (35 mg/kg) or supplemental iron (535 mg/kg). Rats from each diet were divided into carcinogen treatment groups and given two weekly injections of either azoxymethane (AOM) at a dose of 12 mg/kg, or saline. Mucosal tissue was collected 1, 6 and 12 wk following injections and analysed for MnSOD activity, mineral concentration and nuclear aberrations. Results showed that iron supplementation increased nuclear aberrations, and decreased manganese concentration and MnSOD activity in colonic mucosa ot control animals. AOM, and interaction of iron and AOM, also decreased MnSOD activity. A decrease in the activity of this enzyme during carcinogenesis may be one mechanism whereby these dietary factors ultimately increase tumour risk.  相似文献   
102.
Ordered shotgun sequencing (OSS) has been successfully carried out with an Xq25 YAC substrate. yWXD703 DNA was subcloned into lambda phage and sequences of insert ends of the lambda subclones were used to generate a map to select a minimum tiling path of clones to be completely sequenced. The sequence of 135 038 nt contains the entire ANT2 cDNA as well as four other candidates suggested by computer-assisted analyses. One of the putative genes is homologous to a gene implicated in Graves' disease and it, ANT2 and two others are confirmed by EST matches. The results suggest that OSS can be applied to YACs in accord with earlier simulations and further indicate that the sequence of the YAC accurately reflects the sequence of uncloned human DNA.  相似文献   
103.
Protease inhibitors are another class of compounds for treatment of human immunodeficiency virus (HIV)-caused disease. The emergence of resistance to the current anti-HIV drugs makes the determination of potential resistance to protease inhibitors imperative. Here we describe the isolation of an HIV type 1 (HIV-1) resistant to an HIV-protease inhibitor. Serial passage of HIV-1 (strain RF) in the presence of the inhibitor, [2-pyridylacetylisoleucylphenylalanyl-psi (CHOH)]2 (P9941), failed to yield a stock of virus with a resistance phenotype. However, variants of the virus with 6- to 8-fold reduced sensitivity to P9941 were selected by using a combination of plaque assay and endpoint titration. Genetic analysis and computer modeling of the variant proteases revealed a single change in the codon for amino acid 82 (Val-->Ala), which resulted in a protease with lower affinity and reduced sensitivity to this inhibitor and certain, but not all, related inhibitors.  相似文献   
104.
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Past research on help-seeking behaviour and compliance among the mentally ill has mainly been focused on the examination of individual and structural determinants, while the impact of the socio-cultural context has been largely neglected. To examine this impact, we conducted a representative survey among German citizens who were eligible to vote. By means of vignettes describing different mental disorders we recorded the lay public's preferences for various treatment methods, together with their subjective reasons for voicing these particular preferences. While we found that psychotherapy was generally held in high esteem by the lay public, psychopharmacotherapy was rejected by the vast majority of respondents. This pattern was observed for all of the mental disorders included in our survey. While the public's image of psychotherapy is largely determined by popular views on psychoanalysis, public opinion about psychotropic drugs is strongly influenced by characteristics associated with tranquillizers. Among the different psychotherapeutic approaches, psychoanalysis is the preferred method among respondents in the western part of Germany, while the lay public in the eastern part tends to endorse group therapy. Finally, our research showed a considerable difference between the conceptions held by the lay public and those of psychiatric experts with regard to the adequate treatment of mental disorders. This, in turn, should not be without consequence for help-seeking behaviour and patient compliance.  相似文献   
106.
Twenty patients with histologically documented superficial bladder cancer (Ta, T1, Tis) were treated with intravesical administration of TNF 400-1800 micrograms. Of 18 patients with a marker lesion, 2 obtained a complete response for 8+ and 18 months. Two had a partial response and were given other intravesical therapies after 5 and 7 months. No or minimal systemic absorption of TNF was observed and documented in 4 of 20 patients by pharmacokinetic studies, and no patients developed antibodies to intravesically administered TNF. TNF was well tolerated in doses up to 1800 micrograms. No systemic or local side effects were observed. Modest activity was attained with intravesical TNF, even in pretreated patients.  相似文献   
107.
We have previously demonstrated antibody production to a glioma-associated variant form of the human epidermal growth factor receptor in rabbits that had received a synthetic peptide mimicking the unique primary structure of the variant protein as immunogen. We report here the response of mice, rabbits, goats, and macaques immunized by various protocols to this peptide. Titers to both peptide- and cell-elaborated variant receptor were measured, and the capacity to recognize the variant receptor in human tumor samples was determined. Within the range of species and strains investigated, we demonstrated a variable species-associated response to the peptide (rabbits > mice > goats > rats > macaques). Rabbits and a single goat produced specific, high titer antibody activity to the variant receptor protein following immunization with peptide alone. Murine titers to the parent protein were not appreciable following peptide immunization alone; additional immunization with variant receptor as expressed on cell membranes was used to boost this response.  相似文献   
108.
109.
CONTEXT: HBV infection is endemic in Brazil and acute HBV infection is still a common disease. OBJECTIVE: To analyze incidence, risk factors and evolution of acute HBV infection. SETTING: University Hospital. PATIENTS: 357 patients with acute HBV infection, comparing two periods: 1985-1989 vs. 1990-1994. RESULTS: The overall incidence declined from 50 new cases/year in 1985-89 (30% of all cases) to 25 new cases/year in 1990-94 (8% of all cases). Transmission among male homosexuals (3.9% of cases in 85-89) declined to 1.3% in 90-94 (p > 0.05). Amongst health care workers (HCW) it declined from 8.2% to 2.0% (p = 0.02). Conversely, heterosexual transmission increased from 4.8% to 10.1% (p = 0.06). Chronification of HBV infection following the acute episode was observed in 1.7%. Fulminant hepatic failure was seen in 3.4%. However, 27.2% of patients were lost to follow-up before normalization of the biochemical tests. CONCLUSIONS: The different patterns of risk factors observed is probably related to measures for preventing AIDS and to HCW vaccination programs. Chronification following acute episodes was not a common event.  相似文献   
110.
Satisfactory pain relief with postoperative extradural bupivacaine increases the amount of breast feeding after Caesarean section. To investigate the effect of extradural buprenorphine, we have evaluated the amount of breast feeding and the gain in infant weight for 11 days after Caesarean section in patients who received continuous extradural bupivacaine with or without buprenorphine. Extradural buprenorphine significantly decreased both measures although there was no significant difference in pain intensity. We suggest that extradural buprenorphine suppressed breast feeding after Caesarean section.  相似文献   
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