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111.
P Levin  M Haji  J A Joseph  G S Roth 《Life sciences》1983,32(15):1743-1749
Administration of highly purified rat prolactin by miniosmotic pump increases striatal dopamine receptor concentrations in both mature (4-6 months) and senescent (24 months) male Wistar rats. Although receptor levels in untreated rats are about 30% lower in the senescent group, elevated levels following prolactin are not significantly different between ages. Increases in circulating prolactin levels after 7 days of treatment were not detectable at the low concentrations used (150 ng/hr). In fact, there was a trend toward decreases in circulating prolactin concentrations to the same level in both groups after treatment, despite substantially elevated basal levels in many of the senescent rats.  相似文献   
112.
Cytomorphological spectrum in scar endometriosis: a study of eight cases   总被引:9,自引:0,他引:9  
OBJECTIVE: Endometriosis due to ectopic endometrial tissue that responds to hormonal stimulation and is extremely rare in a surgical scar appearing in 0.1% of women who have undergone Caesarean section. Fine needle aspiration cytology (FNAC) can be a valuable diagnostic aid in the evaluation of these subcutaneous abdominal masses. METHODS: We present the cytomorphological spectrum in eight cases of abdominal wall endometriosis diagnosed by FNAC over a 6-year period (June 1998-June 2004) in Mubarak Al-Kabeer Hospital (Kuwait). The patients ranged from 27 to 56 years of age. Seven had a prior Caesarean section and one had a hysterectomy for fibroid. They presented 3-8 years later with nodules in/near the abdominal scar. Five cases presented with a painful nodule, fluctuant with the menstrual cycle. RESULTS: Cytological findings comprised epithelial clusters and fusiform stromal cells with numerous haemosiderin-laden macrophages. Mild to moderate epithelial atypia was observed in three cases. A diagnosis of endometriosis was rendered in all the eight cases and tissue was available in four cases. CONCLUSIONS: Endometriotic nodules need to be differentiated from other benign/malignant masses and evaluated for possible malignant transformation. FNAC provides a safe and effective tool for diagnosis thereby obviating the need for other procedures.  相似文献   
113.
We have previously shown a reduction in anaemia and wasting malnutrition in infants <3 years old in Pemba Island, Zanzibar, following repeated anthelminthic treatment for the endemic gastrointestinal (GI) nematodes Ascaris lumbricoides, hookworm and Trichuris trichiura. In view of the low intensity of worm infections in this age group, this was unexpected, and it was proposed that immune responses to the worms rather than their direct effects may play a significant role in morbidity in infants and that anthelminthic treatment may alleviate such effects. Therefore, the primary aims of this study were to characterise the immune response to initial/early GI nematode infections in infants and the effects of anthelminthic treatment on such immune responses. The frequency and levels of Th1/Th2 cytokines (IL-5, IL-13, IFN-γ and IL-10) induced by the worms were evaluated in 666 infants aged 6–24 months using the Whole Blood Assay. Ascaris and hookworm antigens induced predominantly Th2 cytokine responses, and levels of IL-5 and IL-13 were significantly correlated. The frequencies and levels of responses were higher for both Ascaris positive and hookworm positive infants compared with worm negative individuals, but very few infants made Trichuris-specific cytokine responses. Infants treated every 3 months with mebendazole showed a significantly lower prevalence of infection compared with placebo-treated controls at one year following baseline. At follow-up, cytokine responses to Ascaris and hookworm antigens, which remained Th2 biased, were increased compared with baseline but were not significantly affected by treatment. However, blood eosinophil levels, which were elevated in worm-infected children, were significantly lower in treated children. Thus the effect of deworming in this age group on anaemia and wasting malnutrition, which were replicated in this study, could not be explained by modification of cytokine responses but may be related to eosinophil function.  相似文献   
114.
Promotion of ethylene biosynthesis in peach mesocarp discs by auxin   总被引:2,自引:0,他引:2  
In this study, we investigated the ability of auxin to promote ethylenebiosynthesis in fruit tissue. Discs prepared from preclimacteric peach fruit(Prunus persica L. Batsch cv.Akatsuki) were incubated for 3 weeks on a solid MS medium containing variousconcentrations of 1-naphthaleneacetic acid (NAA). Higher ethylene productionwasobserved with an increasing concentration of NAA. As the developmental stageprogressed, the time it took for the discs to produce ethylene became shorterand the amount of ethylene became greater. Auxin-induced ethylene productionwaseffectively inhibited by adding 100 M ofCoCl2 to the medium. The stimulatory effect of auxin on anthocyaninformation was not affected by Co2+, although softening wasinhibited, suggesting that the effect of auxin on softening is mediated byethylene.  相似文献   
115.
In this paper, analysis of free nucleotides from mouseliver tissue during different day times has been described. Perchloric acid extract of mouse liver tissue was neutralized with tri-N-octylamine in trichlorotriflouroethane and after removal of ClO4(-), subjected to preliminary purification on a Cu(2+)-loaded column of Chelex 100. A high-pressure liquid chromatographic (HPLC) anion-exchange procedure used in the study gave a good resolution of free nucleotides on a single column.  相似文献   
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118.
The production of short anticancer peptides in recombinant form is an alternative method for costly chemical manufacturing. However, the limitations of host toxicity, bioactivity and column purification have impaired production in mass quantities. In this study, short cationic peptides were produced in aggregated inclusion bodies by double fusion with a central protein that has anti-cancer activity. The anticancer peptides Tachiplicin I (TACH) and Latarcin 1 (LATA) were fused with the N- and C-terminus of the MAP30 protein, respectively. We successfully produced the recombinant TACH-MAP30-LATA protein and MAP30 alone in E. coli that represented 59% and 68% of the inclusion bodies. The purified form of the inclusion bodies was prepared by eliminating host cell proteins through multiple washing steps and semi-solubilization in alkaline buffer. The purified active protein was recovered by inclusive solubilization at pH 12.5 in the presence of 2 M urea and refolded in alkaline buffer containing oxides and reduced glutathione. The peptide-fusion protein showed lower CC50 values against cancer cells (HepG2, 0.35±0.1 μM and MCF-7, 0.58±0.1 μM) compared with normal cells (WRL68, 1.83±0.2 μM and ARPE19, 2.5±0.1 μM) with outstanding activity compared with its individual components. The presence of the short peptides facilitated the entry of the peptide fusion protein into cancer cells (1.8 to 2.2-fold) compared with MAP30 alone through direct interaction with the cell membrane. The cancer chemotherapy agent doxorubicin showed higher efficiency and selectivity against cancer cells in combination with the peptide- fusion protein. This study provides new data on the mass production of short anticancer peptides as inclusion bodies in E. coli by fusion with a central protein that has similar activity. The product was biologically active against cancer cells compared with normal cells and enhanced the activity and selective delivery of an anticancer chemotherapy agent.  相似文献   
119.

Background

Complementary and alternative medicine (CAM) use has become increasingly popular among patients with cancer. The purposes of this study were to compare the QOL in CAM users and non-CAM users and to determine whether CAM use influences QOL among breast cancer patients during chemotherapy.

Methodology

A cross-sectional survey was conducted at two outpatient chemotherapy centers. A total of 546 patients completed the questionnaires on CAM use. QOL was evaluated based on the European Organization for Research and Treatment of Cancer (EORTC) core quality of life (QLQ-C30) and breast cancer-specific quality of life (QLQ-BR23) questionnaires.

Results

A total of 70.7% of patients were identified as CAM users. There was no significant difference in global health status scores and in all five subscales of the QLQ C30 functional scales between CAM users and non-CAM users. On the QLQ-C30 symptom scales, CAM users (44.96±3.89) had significantly (p = 0.01) higher mean scores for financial difficulties than non-CAM users (36.29±4.81). On the QLQ-BR23 functional scales, CAM users reported significantly higher mean scores for sexual enjoyment (6.01±12.84 vs. 4.64±12.76, p = 0.04) than non-CAM users. On the QLQ-BR23 symptom scales, CAM users reported higher systemic therapy side effects (41.34±2.01 vs. 37.22±2.48, p = 0.04) and breast symptoms (15.76±2.13 vs. 11.08±2.62, p = 0.02) than non-CAM users. Multivariate logistic regression analysis indicated that the use of CAM modality was not significantly associated with higher global health status scores (p = 0.71).

Conclusion

While the findings indicated that there was no significant difference between users and non-users of CAM in terms of QOL, CAM may be used by health professionals as a surrogate to monitor patients with higher systemic therapy side effects and breast symptoms. Furthermore, given that CAM users reported higher financial burdens (which may have contributed to increased distress), patients should be encouraged to discuss the potential benefits and/or disadvantages of using CAM with their healthcare providers.  相似文献   
120.
The Insulin/IGF-like signalling (IIS) pathway plays an evolutionarily conserved role in ageing. In model organisms reduced IIS extends lifespan and ameliorates some forms of functional senescence. However, little is known about IIS in nervous system ageing and behavioural senescence. To investigate this role in Drosophila melanogaster, we measured the effect of reduced IIS on senescence of two locomotor behaviours, negative geotaxis and exploratory walking. Two long-lived fly models with systemic IIS reductions (daGAL4/UAS-InRDN (ubiquitous expression of a dominant negative insulin receptor) and d2GAL/UAS-rpr (ablation of insulin-like peptide producing cells)) showed an amelioration of negative geotaxis senescence similar to that previously reported for the long-lived IIS mutant chico. In contrast, exploratory walking in daGAL4/UAS-InRDN and d2GAL/UAS-rpr flies declined with age similarly to controls. To determine the contribution of IIS in the nervous system to these altered senescence patterns and lifespan, the InRDN was targeted to neurons (elavGAL4/UAS-InRDN), which resulted in extension of lifespan in females, normal negative geotaxis senescence in males and females, and detrimental effects on age-specific exploratory walking behaviour in males and females. These data indicate that the Drosophila insulin receptor independently modulates lifespan and age-specific function of different types of locomotor behaviour. The data suggest that ameliorated negative geotaxis senescence of long-lived flies with systemic IIS reductions is due to ageing related effects of reduced IIS outside the nervous system. The lifespan extension and coincident detrimental or neutral effects on locomotor function with a neuron specific reduction (elavGAL4/UAS-InRDN) indicates that reduced IIS is not beneficial to the neural circuitry underlying the behaviours despite increasing lifespan.  相似文献   
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