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排序方式: 共有433条查询结果,搜索用时 46 毫秒
1.
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3.
Adverse reaction to intravenous gadoteridol 总被引:1,自引:0,他引:1
4.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
5.
6.
Gene conversion is a likely cause of mutation in PKD1 总被引:3,自引:0,他引:3
Watnick TJ; Gandolph MA; Weber H; Neumann HP; Germino GG 《Human molecular genetics》1998,7(8):1239-1243
Approximately 70% of the gene responsible for the most common form of
autosomal dominant polycystic kidney disease ( PKD1 ) is replicated in
several highly homologous copies located more proximally on chromosome 16.
We recently have described a novel technique for mutation detection in the
duplicated region of PKD1 that circumvents the difficulties posed by these
homologs. We have used this method to identify two patients with a nearly
identical cluster of base pair substitutions in exon 23. Since pseudogenes
are known to be reservoirs for mutation via gene conversion events for a
number of other diseases, we decided to test whether these sequence
differences in PKD1 could have arisen as a result of this mechanism. Using
changes in restriction digest patterns, we were able to show that these
sequence substitutions are also present in N23HA, a rodent-human somatic
cell hybrid that contains only the PKD1 homologs. Moreover, these changes
were also detected in total DNA from several affected and unaffected
individuals that did not harbor this mutation in their PKD1 gene copy. This
is the first example of gene conversion in PKD1 , and our findings
highlight the importance of using gene-specific reagents in defining PKD1
mutations.
相似文献
7.
Hollenbach JA Thomson G Cao K Fernandez-Vina M Erlich HA Bugawan TL Winkler C Winter M Klitz W 《Human immunology》2001,62(4):378-390
Genetic variation of the Human Leukocyte Antigen region (HLA) in three Amerindian populations from the Southern Mexican state of Oaxaca, the Zapotec, Mixtec and the Mixe is examined. Individuals were typed using PCR-SSOP for four class II loci (DRB1, DQA1, DQB1, DPB1) and three class I loci (HLA-A, -B, and -C). Based on known HLA distributions, European admixture ranged from 1% to 10%. Individuals with European alleles were excluded from subsequent analysis. New alleles were revealed at each of the class I loci. In general, genotype frequencies were in Hardy-Weinberg equilibrium, although some deviations were detected. Allele frequency distributions at the DRB1, DQA1, DQB1 and HLA-A loci in all populations were more even than expected under neutrality, supporting a model of balancing selection at these loci. A history of directional selection for DPB1 in all three populations was indicated, as homozygosity values were significantly above expected values. Allele frequency distributions at HLA-B and HLA-C did not differ significantly from neutrality expectations. The data also provide evidence from linkage disequilibrium that strong haplotypic associations are present across the entire HLA region in each of the populations. Significant overall linkage disequilibrium exists between all pairs of loci typed in these populations, except those which include the DPB1 locus. These associations exist despite the fact that the recombination fraction between HLA-A, in the class I region, and DQB1, in the class II region, may exceed 0.02. One explanation is that selective pressures are maintaining the relationships between particular alleles at these loci in these populations. These relationships are maintained in general across the entire HLA region in the Oaxacan Amerindians, with the exception of DPB1. 相似文献
8.
Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings. 相似文献
9.
This follow-up study was undertaken in an effort to ascertain the morbidity in the survivors of infants ≤2000 g birthweight cared for in the two Rockhampton intensive care nurseries.
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
Methodology:
The records of all infants ≤2000 g delivered in or transferred to Rockhampton during the 11 year period 1979 through 1989 inclusive were extracted. Efforts were made to contact and examine all of these children. Those found to be disabled were assessed as being mildly, moderately or severely affected.
Results:
Of the 482 infants of birthweight ≤2000 g treated in the period under review, 393 survived to be discharged from hospital. Eight were known to have died subsequently. Of the remaining 385 children, 288 (74.8%) were able to be contacted and their health status determined. A total of 36 infants were found to have significant disabilities. Twenty-four were mildly affected, five moderately and seven severely affected. Severe disability in infants of ≤1000 g was 16% (3/19).
Conclusions:
The incidence of disability was established in 74.8% of the surviving population, It was not dissimilar to the incidence of disability in similar birthweight groups in some Australian tertiary centres for the years under study. It is emphasized that the follow-up was incomplete and recognized that the survival rates and incidence of disability in survivors has improved in tertiary centres since the time frame of this study. 相似文献
10.
Arif JM; Gairola CG; Glauert HP; Kelloff GJ; Lubet RA; Gupta RC 《Carcinogenesis》1998,19(8):1515-1517
The present study investigated the effects of dietary oltipraz on cigarette
smoke-related lipophilic DNA adduct formation. Female Sprague- Dawley rats
were exposed daily to sidestream cigarette smoke in a whole- body exposure
chamber 6 h/day for 4 consecutive weeks. One group of rats was maintained
on control diet while another group received the same diet supplemented
with either a low (167 p.p.m.) or high (500 p.p.m.) dose of oltipraz,
starting 1 week prior to initiation of smoke exposure until the end of the
experiment. Analysis of lipophilic DNA adducts by the nuclease P1-mediated
32P-post-labeling showed up to five smoke-related adducts. Adduct no. 5
predominated in both the lung and the heart while adduct nos 3 and 2
predominated in the trachea and bladder, respectively. Quantitative
analysis revealed that the total adduct level was the highest in lungs
(270+/-68 adducts/10(10) nucleotides), followed by trachea (196+/-48
adducts/10(10) nucleotides), heart (141+/-22 adducts/10(10) nucleotides)
and bladder (85+/-16 adducts/10(10) nucleotides). High dose oltipraz
treatment reduced the adduct levels in lungs and bladder by >60%, while
the reduction in lungs in the low-dose group was approximately 35%. In
trachea, the effect of low and high dietary oltipraz on smoke DNA adduction
was equivocal, while smoke-related DNA adducts in the heart were minimally
inhibited by high-dose oltipraz. In a repeat experiment that employed a
3-fold lower dose of cigarette smoke, oltipraz (500 p.p.m.) was found to
inhibit the formation of DNA adducts in rat lungs and trachea by 80 and
65%, respectively. These data clearly demonstrate a high efficacy of
oltipraz in inhibiting the formation of cigarette smoke-induced DNA adducts
in the target tissues.
相似文献