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Mutants of human prothymosin alpha with impaired ability to inhibit yeast Saccharomyces cerevisiae. cerevisiae cell growth were characterized. Two types of prothymosin alpha-inactivating mutations were observed. Mutations that belong to the first type compromised the nuclear entry of prothymosin alpha by affecting its nuclear localization signal. Analysis of subcellular distribution of GFP-prothymosin alpha fusions revealed a bipartite nuclear localization signal that is both necessary and sufficient for nuclear import of the protein in human cells. Mutations of the second type abrogated the inhibitory action of prothymosin alpha through an unknown mechanism, without influencing the nuclear import of the protein.  相似文献   
53.
Hearing loss from combined exposures among petroleum refinery workers   总被引:2,自引:0,他引:2  
Seventy-three consecutive cases of childhood acute lymphoblastic leukemia (ALL) diagnosed and managed in Queen Mary Hospital over a 10-year period from 1985 to 1994 were retrospectively analysed for their presenting features and treatment outcome. The 48 boys and 25 girls ranged in age from 0.4 to 14.2 years (median: 4.3 years). Bone and joint pain was a relatively common presenting feature besides fever, hepatosplenomegaly and lymphadenopathy. Immunophenotyping of blast cells showed: 51 B-cell precursor ALL, one B-ALL, 10 T-ALL and three myeloid-antigen positive ALL. Eight cases were unclassified since immunophenotyping had not been performed. Out of the 73 patients, treatment outcome was analysed in 20 cases treated with UKALL-VIII regimen and 28 cases treated with either the UKALL-XI regimen or the Hong Kong Children Cancer Study Group (HKCCSG) protocol which was modelled upon UKALL-XI. Although complete remission rates were similar between the two groups, patients treated with the former regimen that was less intensified suffered more relapses than the latter (56 per cent versus 21 per cent, P = 0.04). There were, however, no significant differences both in event-free survival (38.2 +/- 11.2 per cent versus 71.3 +/- 9.3 per cent, P = 0.12) and overall survival (70.0 +/- 10.2 per cent versus 79.6 +/- 8.3 per cent, P = 0.41) between the two groups at 3 years by long-rank test. With the use of risk-directed therapy and improved supportive care, two-thirds of our patients are able to enjoy long-term event-free survival.  相似文献   
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Sex differences in the activity of aromatase cytochrome P450 (CYP19) in the rat brain have been reported during pre- and postnatal development. It is unclear, however, whether these differences are reflected by corresponding differences in specific mRNA levels. To address this question, we have examined aromatase mRNA levels in specific regions of male and female rat brains by means of in situ hybridization (ISH). At prenatal stages of development, i.e. at gestational day 18 (GD18) and GD20, aromatase mRNA was detected in several preoptic, hypothalamic and limbic brain regions. Semiquantitative analysis of aromatase mRNA did not reveal sex differences in any of these regions. In contrast, clear-cut sex differences were determined at postnatal day (PN) 2; male animals expressed significantly more aromatase mRNA in the bed nucleus of stria terminalis (BST) and the sexually dimorphic nucleus of the preoptic area (SDN). Smaller but still significant differences (females > males) were obtained in the medial preoptic area (MPO). At PN6, sex differences of aromatase mRNA signals (males > females) were still present in the BST, but were no longer detectable in the SDN and the MPO. At PN15 and in adult animals, aromatase mRNA levels were similar in BST and medical amygdaloid nucleus of male and female rats. Since aromatase mRNA expression decreases during postnatal development, no ISH signals could be detected anymore in MPO, SDN and ventromedial hypothalamic nucleus. Our results are consistent with the concept that differential regulation of aromatase mRNA expression might be important for the establishment of different neuronal circuitry in male and female animals.  相似文献   
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Incorporation of planar waveguide technology into a spectroelectrochemical sensor is described. In this sensor design, a potassium ion-exchanged BK7 glass waveguide was over-coated with a thin film of indium tin oxide (ITO) that served as an optically transparent electrode. A chemically selective film was spin-coated on top of the ITO film. The sensor supported five optical modes at 442 nm and three at 633 nm. Investigations on the impact of the ITO film on the optical properties of the waveguide and on the spectroelectrochemical performance of the sensor are reported. Sensing was based on the change in attenuation of light propagated through the waveguide resulting from an optically absorbing analyte. By applying either a triangular or square wave excitation potential waveform, electromodulation of the optical signal has been demonstrated with Fe(CN)6(3-/4-) as a model electroactive couple that partitions into a PDMDAAC-SiO2 film [where PDMDAAC = poly(dimethyldiallylammonium chloride)] and absorbs at 442 nm.  相似文献   
58.
An acute pulpalgia and temporomandibular disorders can produce many of the same symptoms. To illustrate identification of an acute pulpalgia as a component in TMD, the authors review the evaluation of 11 patients at a clinic that specializes in TMD treatment. During the evaluation, thermal testing and periodontal ligament anesthesia were used to identify the offending tooth. After receiving endodontic treatment or having the tooth extracted, patients reported either complete or partial relief of TMD symptoms. The authors provide questions that may help practitioners identify a tooth with an acute pulpalgia as a contributing factor to TMD symptoms and suggest a technique to confirm this diagnosis.  相似文献   
59.
Endophthalmitis after keratotomy is rare and usually occurs soon after surgery. A 56-year-old woman with mild dry-eye symptoms developed keratitis complicated by endophthalmitis 3 years after astigmatic keratotomy (AK). The keratitis lasted for less than 1 day in the upper keratotomy incision. Corneal cultures yielded. Pseudomonas aeruginosa. Keratitis progressed to endophthalmitis 1 day after the detection of keratitis. The inflammation was controlled with intravitreal, subconjunctival, topical, and systemic antibiotics. This case demonstrates the potential risk of endophthalmitis developing very shortly after late keratitis of AK incisions. Vigorous early treatment and close follow-up seem justifiable in any keratitis associated with a keratotomy incision.  相似文献   
60.
A recent report in the literature suggested a link between occupational exposure to lead and brain cancer. To explore the hypothesis, we applied a job-exposure matrix for lead to the occupation and industry codes given on the death certificate of 27,060 brain cancer cases and 108,240 controls who died of non-malignant diseases in 24 US states in 1984-1992. Brain cancer risk increased by probability of exposure to lead among Caucasian men and women with high-level exposure, with a significant twofold excess among Caucasian men with high probability and high level of exposure to lead (odds ratio = 2.1; 95% confidence interval, 1.1-4.0). Risks were also elevated in the low- and medium-probability cells for African-American men with high-level exposure to lead. Trend by intensity level was statistically significant among African-American men (all probabilities combined). Although exposure assessment was based solely on the occupation and industry reported on the death certificate, these results add to other epidemiologic and experimental findings in lending some support to the hypothesis of an association between occupational exposure to lead and brain cancer risk. Analytic studies are warranted to further test this hypothesis.  相似文献   
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