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1.
BARI NUHOLU ALI AYYILDIZ VECIHI FIDAN ÖZDEN CEBECI UUR KOAR CANKON GERMIYANOLU 《International journal of urology》2006,13(2):109-110
OBJECTIVE: Nocturnal enuresis is a common pediatric problem, the etiology of which is unclear. In recent years, various studies have been published stating that children with nocturnal enuresis exhibit growth and skeletal maturation retardation. METHODS: In this cross-sectional study, we included 27 patients (16 boys, 11 girls) between the ages of 6 and 14 years who had presented with primary nocturnal enuresis (PNE) complaints. We included in the evaluation 19 healthy subjects (12 boys, 7 girls), who were the siblings of the children with PNE, as the control group. RESULTS: The patients in both groups were similar in chronological age, bone age, height and weight, with no significant difference between groups (P>0.05). CONCLUSION: The two groups in our study consisted of the same genetic background. Thus, our results were found to be different from the previous studies. We have concluded that there is no direct relationship between enuresis nocturnal and skeletal maturation. 相似文献
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3.
AR Jones BSC AJP Sandison FRCS WJ Owen MS FRCS 《International journal of clinical practice》1997,51(5):294-295
Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons. 相似文献
4.
Ultrastructural changes in the cochlear hair cells during the early stages of gentamicin intoxication were investigated after tri-aldehyde primary fixation and OSO4/K4Ru(CN)6 post-fixation. In cochleas treated for 5, 10 and 15 days with gentamicin the individual outer hair cells (OHC1, OHC2 and OHC3) were randomly affected. Degeneration of the inner hair cells was not observed at this stage. Ultrastructurally, the earliest identifiable changes were an increase in lysosomes, proliferation of the endoplasmic reticulum, and formation of Hensen's bodies. This was followed by dilatation of the endoplasmic reticulum and the nuclear envelope, giving rise to extensive cytoplasmic vacuolation. These results demonstrate that gentamicin-induced changes primarily involve the cell's synthetic apparatus. All further intracellular changes occur at a much later stage and are therefore to be considered secondary events. 相似文献
5.
Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability 总被引:1,自引:15,他引:1
La Spada AR; Peterson KR; Meadows SA; McClain ME; Jeng G; Chmelar RS; Haugen HA; Chen K; Singer MJ; Moore D; Trask BJ; Fischbeck KH; Clegg CH; McKnight GS 《Human molecular genetics》1998,7(6):959-967
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG
repeat expansion in the first exon of the androgen receptor (AR) gene.
Disease-associated alleles (37-66 CAGs) change in length when transmitted
from parents to offspring, with a significantly greater tendency to shift
size when inherited paternally. As transgenic mice carrying human AR cDNAs
with 45 and 66 CAG repeats do not display repeat instability, we attempted
to model trinucleotide repeat instability by generating transgenic mice
with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions
in their genomic context. Studies of independent lines of AR YAC transgenic
mice with CAG 45 alleles reveal intergenerational instability at an overall
rate of approximately 10%. We also find that the 45 CAG repeat tracts are
significantly more unstable with maternal transmission and as the
transmitting mother ages. Of all the CAG/CTG repeat transgenic mice
produced to date the AR YAC CAG 45 mice are unstable with the smallest
trinucleotide repeat mutations, suggesting that the length threshold for
repeat instability in the mouse may be lowered by including the appropriate
flanking human DNA sequences. By sequence-tagged site content analysis and
long range mapping we determined that one unstable transgenic line has
integrated an approximately 70 kb segment of the AR locus due to
fragmentation of the AR YAC. Identification of the cis - acting elements
that permit CAG tract instability and the trans -acting factors that
modulate repeat instability in the AR YAC CAG 45 mice may provide insights
into the molecular basis of trinucleotide repeat instability in humans.
相似文献
6.
P?Mallick J?Chakrabarti Mallick B?Guha AR?Khuda-BukhshEmail author 《BMC complementary and alternative medicine》2003,3(1):7
Background
Arsenic in groundwater and its accumulation in plants and animals have assumed a menacing proportion in a large part of West Bengal, India and adjoining areas of Bangladesh. Because of the tremendous magnitude of the problem, there seems to be no way to tackle the problem overnight. Efforts to provide arsenic free water to the millions of people living in these dreaded zones are being made, but are awfully inadequate. In our quest for finding out an easy, safe and affordable means to combat this problem, a homeopathic drug, Arsenicum Album-30, appears to yield promising results in mice. The relative efficacies of two micro doses of this drug, namely, Arsenicum Album-30 and Arsenicum Album-200, in combating arsenic toxicity have been determined in the present study on the basis of some accepted biochemical protocols. 相似文献7.
Background
The current status of radioiodine-131 (RaI) dosimetry for Graves' hyperthyroidism is not clear. Recurrent hyperthyroidism and iatrogenic hypothyroidism are two problems which interact such that trying to solve one leads to exacerbation of the other. Optimized RaI therapy has therefore begun to be defined just in terms of early hypothyroidism (ablative therapy) as physicians have given up on reducing hypothyroidism.Methods
Optimized therapy is evaluated both in terms of the greatest separation of cure rate from hypothyroidism rate (non-ablative therapy) or in terms of early hypothyroidism (ablative therapy) by mathematical modeling of outcome after radioiodine and critically discussing the three common methods of RaI dosing for Graves' disease.Results
Cure follows a logarithmic relationship to activity administered or absorbed dose, while hypothyroidism follows a linear relationship. The effect of including or omitting factors in the calculation of the administered I–131 activity such as the measured thyroid uptake and effective half-life of RaI or giving extra compensation for gland size is discussed.Conclusions
Very little benefit can be gained by employing complicated methods of RaI dose selection for non-ablative therapy since the standard activity model shows the best potential for cure and prolonged euthyroidism. For ablative therapy, a standard MBq/g dosing provides the best outcome in terms of cure and early hypothyroidism. 相似文献8.
Hermansky-Pudlak syndrome type 4 in a patient from Sri Lanka with pulmonary fibrosis 总被引:1,自引:0,他引:1
Bachli EB Brack T Eppler E Stallmach T Trüeb RM Huizing M Gahl WA 《American journal of medical genetics. Part A》2004,(2):201-207
Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism and a platelet storage pool deficiency. Some patients also develop fatal pulmonary fibrosis and some have granulomatous colitis. Six human genes HPS1, ADB3A, HPS3, HPS4, HPS5, and HPS6 have been identified as cause of the six known subtypes of HPS. While there exist nearly 500 Puerto Rican and non-Puerto Rican HPS-1 patients, very few HPS-4 patients have been reported, and most of these have not been described in detail. We now delineate the clinical characteristics of an HPS-4 patient homozygous for a novel HPS-4 mutation, P685delC. The patient, the first individual with HPS reported from Sri Lanka, had severe pulmonary fibrosis, typical of HPS-1 disease, without granulomatous colitis. We conclude that pulmonary fibrosis occurs as part of HPS-4 and that HPS should be considered in all ethnic groups. 相似文献
9.
10.
Alexander Sparreboom Manon T. Huizing Jan J. B. Boesen Willem J. Nooijen Olaf van Tellingen Jos H. Beijnen 《Cancer chemotherapy and pharmacology》1995,36(4):299-304
Three metabolites of the cytotoxic drug paclitaxel (Taxol) were isolated and purified from the feces of cancer patients receiving the agent as an intravenous infusion. The procedures involved sample homogenization in water followed by liquid-liquid extraction with diethyl ether and high-performance liquid chromatography (HPLC). Approximately 1–3.5 mg of each metabolite was obtained from 100 g of feces. As judged from the chromatographic traces of analytical HPLC with ultraviolet (UV) detection at 227 nm, the purity of each compound was >97%. On-line photodiode-array detection demonstrated that the UV spectrum of the isolated compounds closely resembles that of the parent drug. Mass spectrometry provided evidence that these metabolites are mono- and dihydroxy-substituted derivatives, namely, 6-hydroxypaclitaxel, 3-p-hydroxypaclitaxel, and 6,3-p-dihydroxypaclitaxel. The two 6-hydroxy-substituted metabolites were shown to have lost their cytotoxicity in in vitro clonogenic assays using the A2780 human ovarian carcinoma and the CC531 rat colon-carcinoma tumor cell lines. In addition, the metabolites showed reduced myelotoxic effects as compared with paclitaxel in an in vitro hemopoietic progenitor toxicity assay. Our procedure for the isolation and purification of paclitaxel metabolites in milligram quantities should be useful for testing the biological activities of these compounds and for the preparation of calibration standards essential for pharmockinetics studies. 相似文献