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排序方式: 共有844条查询结果,搜索用时 0 毫秒
831.
832.
In hydronephrosis less than 10 % kidney function is not an indication for nephrectomy in children. 总被引:3,自引:0,他引:3
M A Aziz A Z Hossain T Banu M S Karim N Islam H Sultana M I Alam A Hanif A R Khan 《Zeitschrift für Kinderchirurgie》2002,12(5):304-307
PURPOSE: To reduce the incidence of nephrectomy or hydronephrosis in children. MATERIALS AND METHODS: From September 1998 to October 2000, we treated 58 patients with hydronephrosis; their ages ranged from 35 days to 11 years (mean age 4 years 7 months). All patients were subjected to a DTPA renogram with split function. In 12 patients (study group), kidney function was less than 10 % (range 0 - 10 %). Initially, nephrostomy was carried out in all 12 patients followed by Anderson-Hyne's pyeloplasty after 4 - 6 weeks. Postoperatively renal USG, urine r/m/e & c/s (routine and microscopic examination and culture and sensitivity test), blood urea, serum creatinine were assessed and DMSA scan and DTPA renogram with split functions were carried out in all patients. RESULTS: In the study group, all 12 patients showed improvement of renal function (more than 10 %) after nephrostomy and in all of them pyeloplasty was subsequently carried out within 4 - 6 weeks. There were no significant pre-, peri- or postoperative complications. CONCLUSIONS: Contrary to common practice we do not recommend nephrectomy for hydronephrotic kidneys which show < 10 % of renal function on renogram. The renal functional status improves significantly after a preliminary nephrostomy, thus avoiding the need for a straightforward nephrectomy in children along with all the possible long-term effects of a single kidney. 相似文献
833.
Data on the seroprevalence of antibodies protective against the varicella-zoster virus are needed to develop strategies to prevent varicella infections in Bangladesh. Of 1209 patients evaluated at referral-level health facilities in Dhaka, 943 (78%) had no known history of chickenpox and were tested by latex agglutination for the presence of varicella-zoster antibody in serum. Forty-one per cent (386) of the 943 specimens tested were negative. Seropositivity was highest among neonates (83%), declined sharply to 19% in those aged 7-12 months, and thereafter rose steadily with age until a plateau of 85% was reached after the age of 16 years. This first report of varicella-zoster antibody seroprevalence in Bangladesh suggests that, as in other tropical areas, a significant proportion of children, adolescents and adults are susceptible. Children aged from 15 months to early adolescence might be the most important group to target with the vaccine currently available. However, to ensure successful immunisation, further, population-based seroprevalence data are needed, as are an assessment of the vaccine's acceptability and the accessibility of the target population. Incomplete coverage of young children could result in delayed acquisition, and, ultimately, in more severe disease. 相似文献
834.
835.
Intrauterine growth restriction secondary to placental insufficiency is a major cause of perinatal morbidity and mortality in the United States. Once intrauterine growth restriction is identified, obstetrical management is focused on assuring safety while the fetus continues to mature within a potentially hostile intrauterine environment. In the United States, the approach to management and delivery of the premature growth-restricted fetus is often based on serial biophysical profile evaluations, whereas in Europe it is usually based on the results of cardiotocography. However, there is no single test that seems superior to the other available tests for timing the delivery of the growth-restricted fetus. Therefore, the decision to deliver a fetus, especially at <32 weeks, remains mostly on the basis of empirical management. 相似文献
836.
837.
T-DNA transfer and integration in the ectomycorrhizal fungus Suillus bovinus using hygromycin B as a selectable marker 总被引:4,自引:0,他引:4
The T-DNA of Agrobacterium tumefaciens can be transferred to plants, yeasts, fungi and human cells. Using this system, dikaryotic mycelium of the ectomycorrhizal fungus Suillus bovinus was transformed with recombinant hygromycin B phosphotransferase (hph)and enhanced green fluorescent protein (EGFP) genes fused with a heterologous fungal promoter and CaMV35S terminator. Transformation resulted in hygromycin B-resistant clones, which were mitotically stable. Putative transformants were analysed for the presence of hph and EGFP genes by PCR and Southern analysis. The latter analysis proved both multiple- and single-copy integrations of the genes in the S. bovinus genome. A. tumeficiens transformation should make possible the development of tagged mutagenesis and targeted gene disruption technology for S. bovinus. 相似文献
838.
Milad Ebtedaei Najibeh Alizadeh Hakimeh Ghaleh 《Journal of biomaterials science. Polymer edition》2013,24(15):1433-1453
AbstractIn this work, well-defined poly(dimethylsiloxane)-b-poly(oligo (ethylene glycol) methacrylate) (PDMS-b-POEGMA) amphiphilic block copolymers were synthesized and their effect on human dermal fibroblast were investigated. Anionic ring opening polymerization (ROP) and atom transfer radical polymerization (ATRP) were used to synthesis the block copolymers. The molecular weight of synthesized copolymers ranged from 1000 to 2300?Da by changing the number of both PDMS and POEGMA units. It was found that the copolymer having low molecular weight decreased the fibroblast viability and proliferation by inducing apoptosis. It was proved by flow cytometry and TUNEL assay that human dermal fibroblast experienced apoptosis after exposure to synthesized amphiphilic copolymers. The results of this work suggest the use of PDMS-b-POEGMA amphiphilic copolymers with low molecular weight for hypertrophic scars remediation. 相似文献
839.
Marie-France Marin Florentine Barbey Blake L. Rosenbaum Mira Z. Hammoud Scott P. Orr Mohammed R. Milad 《Psychophysiology》2020,57(1):e13350
Skin conductance response (SCR) is often used as an index of conditioned fear. SCR has been shown to be highly variable, and absence of SC reactivity is sometimes used as criteria for excluding data. It is, however, possible that low or no SC reactivity is the result of a distinct biological signature that underlies individual differences in SCR reactivity. This study examined neural correlates associated with the near absence of SCR conditionability. Archival data from 109 healthy adults aged 18–60 years were pooled. All individuals had participated in a fear conditioning protocol in a fMRI environment, during which two cues were partially reinforced (CS+) with a shock and a third cue was not (CS−). Using SCR to the conditioned stimuli and differential SCR (CS+ minus CS−), we created two groups of 30 individuals: low conditioners (defined as those showing the smallest SCR to the CS+ and smallest differential SCR) and high conditioners (defined as those showing the largest SCR to the CS+ and largest differential SCR). Our analyses showed differences in patterns of brain activations between these two groups during conditioning in the following regions: dorsal anterior cingulate cortex, amygdala, subgenual anterior cingulate cortex, and insular cortex. Our findings suggest that low or absent SCR conditionability is associated with hypoactivation of brain regions involved in fear learning and expression. This highlights the need to be cautious when excluding SCR nonconditioners and to consider the potential implications of such exclusion when interpreting the findings from studies of conditioned fear. 相似文献
840.
Mandolin L. Bartling Seyed A. Rohani Hanif M. Ladak Sumit K. Agrawal 《Journal of anatomy》2021,239(4):771-781
The ossicular chain is a middle ear structure consisting of the small incus, malleus and stapes bones, which transmit tympanic membrane vibrations caused by sound to the inner ear. Despite being shown to be highly variable in shape, there are very few morphological studies of the ossicles. The objective of this study was to use a large sample of cadaveric ossicles to create a set of three-dimensional models and study their statistical variance. Thirty-three cadaveric temporal bone samples were scanned using micro-computed tomography (μCT) and segmented. Statistical shape models (SSMs) were then made for each ossicle to demonstrate the divergence of morphological features. Results revealed that ossicles were most likely to vary in overall size, but that more specific feature variability was found at the manubrium of the malleus, the long process and lenticular process of the incus, and the crura and footplate of the stapes. By analyzing samples as whole ossicular chains, it was revealed that when fixed at the malleus, changes along the chain resulted in a wide variety of final stapes positions. This is the first known study to create high-quality, three-dimensional SSMs of the human ossicles. This information can be used to guide otological surgical training and planning, inform ossicular prosthesis development, and assist with other ossicular studies and applications by improving automated segmentation algorithms. All models have been made publicly available. 相似文献