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21.
The recommended anticoagulation regimen for continuous-flow left ventricular assist device (LVAD) systems is warfarin and aspirin with a targeted international normalized ratio (INR) of 2.0–3.0. Our patient is a 58-year-old male who underwent surgical HeartMate III continuous-flow LVAD implantation 3?months ago outside the country. The patient mistakenly stopped taking warfarin for 1?month prior to presenting to our center for a routine visit. Luckily, the patient was doing very well without any complication despite the fact that his INR was 1.0.  相似文献   
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23.
This study was undertaken in order to compare the interphase and metaphase cytogenetics of 28 patients with ETV6/RUNX1 positive acute lymphoblastic leukemia, at diagnosis and relapse. The median time to relapse was 26 months. The significant fusion positive population heterogeneity revealed at interphase by a commercial probe for ETV6/RUNX1 fusion has not been described before. Six diagnostic samples had a single abnormal population; others had up to five each, which differed in the numbers of RUNX1 signals, and in the retention or loss of the second ETV6 signal. In contrast, the number of fusion signals was more constant. At relapse, there were fewer populations; the largest or unique clone was sometimes a re-emergence of a minor, diagnostic one, with a retained copy of ETV6 and the most RUNX1 signals. Abnormal, fusion negative clones were identified in bone marrow samples at extra-medullary relapse. Variant three or four-way translocations, which involved chromosomes 12 and 21, were prominent among the complex rearrangements revealed by metaphase FISH. The frequency of their occurrence at diagnosis and reappearance at relapse, sometimes accompanied by minor clonal evolution, was another new observation. Other recurrent cytogenetic features included a second copy of the fusion signal in six cases, partial duplication of the long arm of the X chromosome in two cases, and trisomy 10 in three cases. In comparing our data with previously reported cases, a picture is beginning to emerge of certain diagnostic features, which may provide circumstantial evidence of an increased risk of relapse.  相似文献   
24.
Because identification of the species within the "Streptococcus milleri" group is difficult for the clinical laboratory as the species share overlapping phenotypic characteristics, we wished to confirm biochemical identification with identification by 16S rRNA gene sequence analysis. Ninety-four clinical isolates previously identified as the "Streptococcus milleri" group were reclassified as S. anginosus, S. constellatus, or S. intermedius with the API 20 Strep system (bioMerieux Vikek, Hazelton, Mo.) and the Fluo-card (Key Scientific, Round Rock, Tex.). In addition, we determined the Lancefield group, hemolysis, colony size, colony texture, repetitive extragenic palindromic PCR (rep-PCR) pattern, and cellular fatty acid (CFA) profile (MIDI, Newark, Del.). 16S rRNA gene sequence analysis with 40 selected representative strains showed three distinct groups, with S. constellatus and S. intermedius found to be more closely related to each other than to S. anginosus, and further distinguished a biochemically distinct group of urogenital isolates within the S. anginosus group of isolates. Except for strains unreactive with the Fluo-card (8%), all S. anginosus and S. intermedius strains identified by sequencing were similarly identified by biochemical testing. However, 23% of the selected S. constellatus isolates identified by sequencing (9% of all S. constellatus isolates) would have been identified as S. anginosus or S. intermedius by biochemical tests. Although most S. anginosus strains formed one unique cluster by CFA analysis and most S. constellatus strains showed similar rep-PCR patterns, neither method was sufficiently dependable for identification. Whereas Lancefield group or lactose fermentation did not correspond to sequence or biochemical type, S. constellatus was most likely to be beta-hemolytic and S. intermedius was most likely to have a dry colony type. The most frequent isolate in our population was S. constellatus, followed by S. anginosus. There was an association of S. anginosus with a gastrointestinal or urogenital source, and there was an association of S. constellatus and S. intermedius with both the respiratory tract and upper-body abscesses.  相似文献   
25.
Non‐protein‐coding RNAs have increasingly been shown to be an important class of regulatory RNAs having significant roles in regulation of gene expression. The long noncoding RNA (lncRNA) gene family presently constitutes a large number of noncoding RNA (ncRNA) loci almost equaling the number of protein‐coding genes. Nevertheless, the biological roles and mechanisms of the majority of lncRNAs are poorly understood, with exceptions of a very few well‐studied candidates. The availability of genome‐scale variation datasets, and increasing number of variant loci from genome‐wide association studies falling in lncRNA loci have motivated us to understand the patterns of genomic variations in lncRNA loci, their potential functional correlates, and selection in populations. In the present study, we have performed a comprehensive analysis of genomic variations in lncRNA loci. We analyzed for patterns and distributions of genomic variations with respect to potential functional domains in lncRNAs. The analysis reveals a distinct distribution of variations in subclasses of long ncRNAs and in potential functional domains of lncRNAs. We further examined signals of selections and allele frequencies of these prioritized set of lncRNAs. To the best of our knowledge, this is the first and comprehensive large‐scale analysis of genetic variations in long ncRNAs.  相似文献   
26.
The societal cost of preterm birth indicates potential economic gains from interventions that reduce the incidence of preterm birth. Changes in the epidemiology of preterm birth and healthcare costs require periodic updates to cost estimates. Previously reported incremental cost estimates for the United States in 2004 were updated. The discounted present value of the excess cost associated with prematurity for the 2016 US birth cohort was estimated to be $25.2 billion: $17.1 billion for medical care of persons born preterm, $2.0 billion for delivery care, $1.3 billion for early intervention and special education, and $4.8 billion in lost productivity due to associated disabilities in adults. The nominal and inflation-adjusted incremental costs per preterm birth increased by 26% and 4%, respectively, during 2004–2016. The aggregate cost decreased by 4%, associated with declines in overall births and the preterm birth rate and changes in the distribution by gestational age.  相似文献   
27.
Role of copper in mitochondrial iron metabolism   总被引:1,自引:1,他引:1  
Heme synthesis by copper-deficient cells was investigated to elucidate the nature of the defect in intracellular iron metabolism. Iron uptake from transferrin by copper-deficient reticulocytes was 52% of normal, and the rate of heme synthesis was 33% of normal. Hepatic mitochondria isolated from copper-deficient animals were deficient in cytochrome oxidase activity and failed to synthesize heme from ferric iron (Fe III) and protoporphyrin at the normal rate. The rate of heme synthesis correlated with the cytochrome oxidase activity. Heme synthesis from Fe(III) and protoporphyrin by normal mitochondria was enhanced by succinate and inhibited by malonate, antimycin A, azide, and cyanide. It is proposed that an intact electron transport system is required for the reduction of Fe(III), thereby providing a pool of ferrous iron (Fe II) for protoheme and heme a synthesis.  相似文献   
28.
The effect of temperature and pregnant mare's serum gonadotropin (PMSG) was observed on the testes of Uromastix hardwicki at a time of the year (November) when the seminiferous epithelium contained abundant proliferating spermatogonia and some primary spermatocytes. This recrudescent state of the testes was maintained by keeping the animals at 20° for 10 days. But, in lizards kept at 35°, there was a marked decrease in the testis weight. The seminiferous tubules were lined mostly with Sertoli cells and a few resting types of spermatogonia. The interstitial cells were only slightly affected and there was no reduction in androgen concentrations in the testicular tissue or plasma, as measured by testosterone radioimmunoassay. At 20°, injections of 20 IU of PMSG daily for 10 days induced an increase in the number of primary spermatocytes and production of spermatids in certain regions of the tubules. In the PMSG-treated lizards kept at 35° the testes contained a single layer of resting spermatogonia placed along the basement membrane. Under these conditions PMSG failed to maintain the active state of the seminiferous epithelium. Unlike the germinal cells, the interstitial cells were markedly stimulated by PMSG at 20 or 35°. Testicular and plasma androgen levels were increased severalfold in gonadotropin-treated lizards. The elevation of androgen levels as a result of PMSG stimulation was higher in lizards kept at 35°. It is suggested that in Uromastix hardwicki, the germinal epithelium responds differentially to PMSG treatment at the two different temperatures and that the activity of the interstitial cells is not inhibited by hyperthermia.  相似文献   
29.
Anaphylaxis is an acutely presenting life‐threatening medical emergency. Surveys indicate that dentists feel inadequately able to recognize and treat anaphylaxis. This paper reviews the terminology and pathophysiology of anaphylaxis, and describes the recognition and initial management of anaphylaxis for dentists. Dentists should be able to administer intramuscular adrenaline during anaphylaxis at the appropriate dose. The role of further medical care is also explained. Six cases of anaphylaxis arising from dental oral maxillofacial surgery practice are discussed.  相似文献   
30.
High-resolution magnetic resonance (MR) imaging with a surface coil was utilized to evaluate the normal scrotum. Scrotal contents, spermatic canal, and inguinal regions were visualized within the same field of view. Differences in signal intensity in the testis, epididymis, tunica albuginea, fluid, fat, and spermatic cord allowed for clear delineation of these structures in detail. The high contrast and spatial resolution of MR imaging, coupled with the wide field of view and absence of ionizing radiation, make MR imaging well suited for evaluation of the scrotum.  相似文献   
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