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991.
Mueller PR; Ferrucci JT Jr; Simeone JF; Butch RJ; Wittenberg J; White M; Brown AS 《Radiology》1985,155(3):615-618
Twelve abscesses and fluid collections in the lesser peritoneal sac were drained percutaneously using an access route across the intervening liver. This rather unusual access was chosen when other approaches were contraindicated because of surrounding colon, stomach, or spleen. All collections were drained successfully, and no specific complications such as hemorrhage, bile leak, or liver abscess occurred. Placement of an abscess drainage catheter should be done through the peripheral portion of the liver if possible. The technique offers a new, safe approach to percutaneous drainage of hitherto inaccessible collections. 相似文献
992.
RJ Ruben IF Wallace J Gravel 《Indian journal of otolaryngology and head and neck surgery》1997,49(2):94-96
A cohort of lower socio-economic children who experienced multiple and prolonged episodes of otitis media (OM) during their first year of life were compared to an equivalent group of children who were largely free of OM during their first year. Both groups were followed until 9 years of age. The data indicate that children with positive histories of OM performed poorer on a variety of Iinguisitc tasks across the nine year age span than the children with the positive histories of OM. The results suggest that the effect of the otitis media and its accompanying hearing loss on communication skills may extend throughout childhood. 相似文献
993.
994.
Dumaz N; van Kranen HJ; de Vries A; Berg RJ; Wester PW; van Kreijl CF; Sarasin A; Daya-Grosjean L; de Gruijl FR 《Carcinogenesis》1997,18(5):897-904
Mutation spectra of the p53 gene from human skin carcinomas have been
connected to solar UV radiation. For comparison we have characterized the
mutation spectrum of the p53 gene in a very large sample of squamous cell
carcinomas from hairless mice induced with UV of wavelength 280-320 nm
(UV-B), which have substantiated the mutagenic effects of UV-B radiation in
vivo. Tumors from hairless mice, random bred SKH:HR1 as well as inbred
SKH:HRA strains, which are analyzed for mutations in the conserved domains
of the p53 protein present a very specific mutation spectrum. The observed
mutation frequency after chronic UV-B radiation in the p53 gene ranged from
54% (SKH-HRA) to 73% (SKH-HR1) among the 160 tumors analyzed. Over 95% of
the mutations were found at dipyrimidine sites located in the
non-transcribed strand, the majority were C-->T transitions and 5% were
CC-->TT tandem double mutations. Four distinct UV-B mutation hot spots
have been identified for the first time: two major ones at codons 267 (33%)
and 272 (19%) and two minor ones at codons 146 (10%) and 173 (4%). The
codon 267 hot spot consists of a CpG preceded by a pyrimidine, which
confirms in vivo an important role for this UV-B mutable site in
UV-B-induced skin tumors that is not found in other types of mouse tumors.
Comparison with mutation spectra from human skin carcinomas fully validates
the merits of the hairless mouse model for studying the molecular
mechanisms of skin carcinogenesis. For example, the murine hot spot at
codon 272 does have a full equivalent in human skin carcinomas. In
contrast, the human equivalent of the murine codon 267 lacks the
dipyrimidine site and therefore fails to be a pronounced hot spot in human
skin carcinomas; however, this site is one of the major hot spots in human
internal cancers (evidently not induced by UV radiation but probably by
deamination of the 5 methyl cytosine).
相似文献
995.
Carmina E; Wong L; Chang L; Paulson RJ; Sauer MV; Stanczyk FZ; Lobo RA 《Human reproduction (Oxford, England)》1997,12(5):905-909
Polycystic-appearing ovaries (PAO) on ultrasound have been described in a
variety of endocrinopathies and also occur in ovulatory women. By some
investigators this is merely referred to as 'PCO' (polycystic ovaries).
Although there is controversy in this regard, we do not consider women with
PAO/PCO who have no known endocrine disturbance to have polycystic ovary
syndrome (PCOS) and therefore prefer not to use the term 'PCO' which is
often equated with PCOS. We studied 15 ovulatory women with
normal-appearing (NAO) ovaries on ultrasound and 15 matched ovulatory women
with PAO/PCO. Compared to ovulatory women, 25 other women were studied who
were considered to have PCOS. Of these, 15 were overweight and 10 were of
normal weight. All the PCOS women had serum concentrations of luteinizing
hormone (LH), testosterone, unbound testosterone, androstenedione and
dihydroepiandrosterone sulphate (DHEAS) which were significantly higher (P
< 0.01) than values in the normal women, regardless of ovarian
morphology. These values were similar in the two groups of ovulatory women
with NAO and PAO/PCO. Fasting insulin was elevated in women with PCOS with
increased body weight (P < 0.01) and was higher than in ovulatory women
with NAO and PAO/PCO and than in women of normal weight with PCOS. Serum
insulin- like growth factor (IGF)-I and binding protein (BP)-3 were similar
in all groups but serum IGFBP-1 was significantly (P < 0.01) lower in
those women with PCOS with increased body weight, compared to all other
groups. Compared to values in ovulatory women with NAO, serum IGFBP-1 was
also significantly (P < 0.05) lower in women with PAO/PCO and those
women with PCOS of normal weight. These lower values were similar in women
with PAO/PCO and in normal weight women with PCOS. On an individual basis,
an elevation of at least one serum androgen value was found in 33% of women
with PAO/PCO. These data confirm that increased body weight accentuates the
metabolic alterations in PCOS, but suggest that subtle endocrine
disturbances, similar to those that are found in PCOS, may be uncovered in
up to a third of ovulatory women with PAO/PCO. It appears that a
disturbance of the IGF/IGFBP-1 axis is common and apparently closely
associated with alterations in ovarian morphology.
相似文献
996.
Paternal uniparental disomy of chromosome 6 and transient neonatal diabetes mellitus 总被引:3,自引:0,他引:3
Transient neonatal diabetes mellitus occurs in growth-retarded infants, has an incidence of 1 in 400000 live births and has been associated with both paternal uniparental disomy of chromosome 6 and paternal duplications of 6q. We analysed samples from our cohort of patients with transient neonatal diabetes mellitus for uniparental disomy of chromosome 6 using polymorphic microsatellite repeat analysis. We report here the fifth case of paternal uniparental disomy of chromosome 6 associated with classic transient neonatal diabetes mellitus and estimate that uniparental disomy of chromosome 6 accounts for approximately one fifth of cases of transient neonatal diabetes mellitus. 相似文献
997.
抗体/腺病毒复合物为载体的基因定位递送 总被引:3,自引:0,他引:3
临床基因治疗方案中基因载体在疾病部位的靶向递送仍是急待解决的问题。本研究将腺病毒与一种生物素化的特异性抗腺病毒六邻体的多克隆IgG结合,固定于结合了亲和素的胶原蛋白膜上,成功获得腺病毒载体基因靶向定位递送体系。体外稳定性研究结果表明该体系中病毒载体可有效保持活性。通过这种特异性抗体偶联方式,将携带单纯疱疹胸苷激酶(HSVtk)编码基因片断的腺病毒结合在胶原膜上转染大鼠平滑肌细胞(A10),加入更昔洛韦(ganciclovir)后,只有生长在胶原膜上及膜邻近50μm内的细胞被杀死。在使用非特异性抗体的对照实验中,整个培养基范围内的细胞几乎全被杀死。以绿色荧光蛋白(GFP)为报告基因对猪的心肌进行转基因实验,结果显示注射特异性抗体偶联病毒的胶原凝胶比直接注射病毒悬液获得更高效的心室基因表达。所有研究结果表明,通过生物素和特异性抗体使病毒载体固定在胶原蛋白基质上,可达到有效的局部定位基因表达,避免向非病灶部位的扩散,是基因治疗中一种极具发展潜力的载体定位递送方法。 相似文献
998.
LANGUAGE="EN">Summary. In this paper the organisation of a radiology satellite department is described. In the satellite department only bucky examinations are performed, thus avoiding the need for the duplication of sophisticated material and specialized staff. The satellite department maintains as efficient a service as the main radiology department. For this purpose a digital radiology system was chosen for the satellite department. This system permits digital data to be sent to the main location. This results in a maximisation of the advantages of a two-location system as well as avoiding the need for patients' files to be moved between different locations. 相似文献
999.
目的 应用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验对乳糖酶缺乏者小肠粘膜乳糖酶活性进行定量分析。方法 选用4 3名乳糖酶缺乏者(呼气ΔH2 浓度>2 0 μmol mol)作为实验对象,根据乳糖不耐受症状记录分为乳糖吸收不良组(LM)和乳糖不耐受组(LI)。以2 5g1 3C 乳糖和0 . 5g2 H 葡萄糖作为受试底物,分析受试者摄入底物之后各时点血浆中总葡萄糖、1 3C 葡萄糖和2 H 葡萄糖浓度,并计算各时点1 3C 葡萄糖2 H 葡萄糖吸收百分率的比值,以4 5min、6 0min、75min三个时点所得比值的均值作为乳糖消化指数(LDI)来反应小肠乳糖酶活性。结果 乳糖吸收不良组和乳糖不耐受组两组各时点血浆总葡萄糖、1 3C 葡萄糖无显著性差异,乳糖吸收不良组的乳糖消化指数显著高于乳糖不耐受组(0 . 4 7±0 .15vs 0 . 34±0 . 14 ) ;乳糖消化指数与6h累积H2 呼出量无显著性相关关系(r=0 . 12 ,P =0 .4 6 ) ;经H2 呼气试验结果判定为乳糖酶缺乏的个体,经1 3C 乳糖 2 H 葡萄糖负荷试验分析显示小肠粘膜仍存在一定乳糖酶活性。结论 采用双标稳定同位素1 3C 乳糖2 H 葡萄糖负荷试验可以准确、灵敏地定量分析小肠粘膜乳糖酶活性,同时可以计算体内乳糖消化量。 相似文献
1000.
益生菌和酸奶对乳糖不耐受者的作用研究 总被引:7,自引:0,他引:7
目的:研究益生菌和酸奶对乳糖不耐症(lactoseintolerance,LI)者的作用及其机制。方法:以经乳糖负荷试验筛选的乳糖不耐受者11名为对象,持续摄入益生菌(含B.longum)和酸奶(含L.bulgaricus,S.thermophilus,B.animalis)14d进行补充研究。试验分3个阶段,第1阶段为基值阶段1w,第2阶段为补充阶段2w,第3阶段为补充后阶段1w。在第2阶段前后1d分别进行双标稳定同位素13C-lactose/2H-glucose负荷试验,分析受试者摄入底物后6h呼气H2浓度值,以及血浆13C-glucose和2H-glucose浓度,并计算乳糖消化指数(lactosedigestionindex,LDI),乳糖消化量和口—结肠转运时间(orocecaltransittime,OCTT)。整个实验期间共收集5次粪便样本,分析β-半乳糖苷酶活性。结果:在第2阶段补充结束后个体LI症状评分显著低于补充前(7.09±5.50vs16.09±10.03,P<0.05);LDI、乳糖消化量、OCTT和各时间点呼气H2浓度在补充前后无显著性改变;粪便β-半乳糖苷酶活性在补充第1w即开始升高,补充第2w显著高于基值(147.6±165.8IUvs77.3±77.2IU,P<0.05)。结论:持续摄入益生菌和酸奶具有明显改善乳糖不耐受症状的作用,其原因可能与结肠β-半乳糖苷酶活性的增加有关。 相似文献