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A total of 316 patients were included in a play-the-winner (PTW) designed study comparing the safety of enoxaprain started preoperatively versus postoperatively as prophylaxis against venous thromboembolism for digestive surgery. In a PTW-designed study the treatment of any next patient depends on the outcome of the previous patient. If successful, the next patient receives the same treatment, if not, the comparative regimen is given. Excessive bleeding according to specified criteria, severe adverse reactions, clinically detected deep venous thrombosis (DVT), or pulmonary embolism (PE) were criteria for classification as “loser.” The PTW design allocates most patients to the superior treatment. The main variable in PTW studies is the number of consecutive patients receiving the same treatment. In this study 163 patients were allocated to postoperatively started and 153 to preoperatively started prophylaxis with enoxaparin. The frequency of “winners” was found to be 82.8% and 78.4% in the post- and preoperatively treated groups, respectively. No significant differences were found between the groups with regard to frequency of “winners” or the number of consecutive patients before change of treatment. The percentile of survival distribution did not detect superiority of any group. Prophylaxis against postoperative venous thromboembolism for digestive surgery using enoxaparin can safely be started preoperatively. 相似文献
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Gsta Holmgren Sven Bergström Ulf Drugge Erik Lundgren Carin Nording-Sikström Ola Sandgren Lars Steen 《Clinical genetics》1992,41(1):39-41
Familial amyloidotic polyneuropathy (FAP) with a mutation in position 30 of transthyretin (TTR) (previously called prealbumin) is an autosomal dominant inherited disorder characterized by varying degrees of peripheral neuropathy, nephropathy, gastrointestinal problems, and vitreous amyloid. We have earlier diagnosed homozygosity for the TTR-Met30-gene using Southern analysis in four Swedish individuals. We have found it possible to detect homozygosity for the Met-30 mutation by amplifying discrete regions of the TTR-gene using polymerase chain reaction (PCR), and the amplification products restricted with NsiI analysed by gel electrophoresis. Clinical data on seven homozygous individuals, including three new cases, are presented. 相似文献
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Thomas W Stief Ola Ijagha Bettina Weiste Ileana Herzum Harald Renz Martin Max 《Blood coagulation & fibrinolysis》2007,18(2):179-186
This laboratory study tested new methods to analyze hemostasis alterations in septic patients. Samples of ethylenediamine tetraacetic acid (EDTA) plasma and citrated plasma were collected from 62 patients with clinical diagnosis of sepsis. Additionally, a subset of EDTA-plasma samples from each patient was stabilized 1 + 1 with 2.5 mol/l arginine, pH 8.6, to conserve the real hemostasis activation state. EDTA-arginine plasma, EDTA plasma and citrated plasma samples were tested in duplicate. The patients at admission to the intensive care unit had 36 +/- 26 (normal, 0.8 +/- 0.2) ng/ml global endotoxin reactivity, 188 +/- 66% (normal, 100 +/- 20%) fibrinogen function, 179 +/- 66% (normal, 100 +/- 20%) fibrinogen antigen, 4.0 +/- 3.6 (normal, 0.049 +/- 0.025) microg/ml D-dimer, 313 +/- 307% (normal, 100 +/- 30%) plasmin-antiplasmin complex, 8.7 +/- 11.4 (normal, 1.1 +/- 0.7) U/ml plasminogen activator inhibitor-1, 12.1 +/- 10.5 (normal, 1.3 +/- 0.4) ng/ml thrombin-antithrombin III complex, 173 +/- 62% (normal, 100 +/- 20%) thrombin, 568 +/- 225 (normal, 140 +/- 42) pg/ml tissue factor, and 2.56 +/- 2.48 (normal, 0.19 +/- 0.04) microg/ml soluble intercellular adhesion molecule-1. Endotoxin (lipopolysaccharide and/or beta-glucan) reactivity (EDTA plasma), fibrinogen function + antigen + ratio and plasminogen activator inhibitor-1 (citrated plasma), and D-dimer, soluble intercellular adhesion molecule-1, thrombin activity (EDTA-arginine-stabilized plasma) presented large aberrations in septic patients when compared with normal values and may therefore be particularly interesting as markers of hemostasis alteration. Whether the observed alterations are of clinical significance has to be determined in well defined patient groups. 相似文献
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Methylprednisolone treatment in acute spinal cord injury: the myth challenged through a structured analysis of published literature. 总被引:5,自引:0,他引:5
BACKGROUND CONTEXT: Methylprednisolone has evolved during the 1990s, through the results obtained from the National Acute Spinal Cord Injury Studies NASCIS II and III, as a standard treatment in acute spinal injury. PURPOSE: To evaluate the scientific basic for the use of methylprednisolone in acute spinal cord injury. STUDY DESIGN: Systematic review of the accumulated literature. METHODS: Critical evaluation of the data obtained in the NASCIS II and III studies plus other accumulated literature. RESULTS: Analyses have been made on subgroups of the study populations, and the results were based on statistical artefacts. Furthermore, improved functional recovery shown by these studies was not clinically significant. CONCLUSION: There is insufficient evidence to support the use of methylprednisolone as a standard treatment in acute spinal cord injury. 相似文献
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Aaron A. Vogan S. Lorena Ament-Velsquez Eric Bastiaans Ola Wallerman Sven J. Saupe Alexander Suh Hanna Johannesson 《Genome research》2021,31(5):789
The genomes of eukaryotes are full of parasitic sequences known as transposable elements (TEs). Here, we report the discovery of a putative giant tyrosine-recombinase-mobilized DNA transposon, Enterprise, from the model fungus Podospora anserina. Previously, we described a large genomic feature called the Spok block which is notable due to the presence of meiotic drive genes of the Spok gene family. The Spok block ranges from 110 kb to 247 kb and can be present in at least four different genomic locations within P. anserina, despite what is an otherwise highly conserved genome structure. We propose that the reason for its varying positions is that the Spok block is not only capable of meiotic drive but is also capable of transposition. More precisely, the Spok block represents a unique case where the Enterprise has captured the Spoks, thereby parasitizing a resident genomic parasite to become a genomic hyperparasite. Furthermore, we demonstrate that Enterprise (without the Spoks) is found in other fungal lineages, where it can be as large as 70 kb. Lastly, we provide experimental evidence that the Spok block is deleterious, with detrimental effects on spore production in strains which carry it. This union of meiotic drivers and a transposon has created a selfish element of impressive size in Podospora, challenging our perception of how TEs influence genome evolution and broadening the horizons in terms of what the upper limit of transposition may be.Transposable elements (TEs) are major agents of change in eukaryotic genomes. Their ability to selfishly parasitize their host replication machinery has large impacts on both genome size and on gene regulation (Chénais et al. 2012). In extreme cases, TEs can contribute up to 85% of genomic content (Schnable et al. 2009), and expansion and reduction of TEs can result in rapid changes in both genome size and architecture (Haas et al. 2009; Möller and Stukenbrock 2017; Talla et al. 2017). Generally, TEs have small sizes (∼50–12,000 bp) and accomplish these large-scale changes through their sheer number. For example, there are ∼1.1 million Alu elements in the human genome, which have had a large impact on genome evolution (Jurka 2004; Bennett et al. 2008). The largest known cases among Class I retrotransposons are long terminal repeat (LTR) elements that can be as large as 30 kb, but among Class II DNA transposons, Mavericks/Polintons are known to grow as large as 40 kb through the capture of additional open reading frames (ORFs) (Arkhipova and Yushenova 2019). Recently, a behemoth TE named Teratorn was described in teleost fish; it can be up to 182 kb in length, dwarfing all other known TEs. Teratorn has achieved this impressive size by fusing a piggyBac DNA transposon with a herpesvirus, thereby blurring the line between TEs and viruses (Inoue et al. 2017, 2018). Truly massive transposons may be lurking in the depths of many eukaryotic genomes, but the limitations of short-read genome sequencing technologies and the lack of population-level high-quality assemblies may make them difficult to identify.The Spok block is a large genomic feature that was first identified thanks to the presence of the spore killing (Spok) genes in species from the genus Podospora (Grognet et al. 2014; Vogan et al. 2019). The Spoks are selfish genetic elements that bias their transmission to the next generation in a process known as meiotic drive. Here, drive occurs by inducing the death of spores that do not inherit them, through a single protein that operates as both a toxin and an antidote (Grognet et al. 2014; Vogan et al. 2019). The first Spok gene described, Spok1, was discovered in Podospora comata (Grognet et al. 2014). In P. anserina, the homologous gene Spok2 is found at high population frequencies, whereas two other genes of the Spok family, Spok3 and Spok4, are at low to intermediate frequencies (Vogan et al. 2019). Unlike Spok1 and Spok2, however, Spok3 and Spok4 are always associated with a large genomic region (the Spok block). The Spok block can be located at different chromosomal locations in different individuals but is never found more than once in natural strains. The number of Spok genes and the location of the Spok block (which carries Spok3, Spok4, or both) define the overall meiotic driver behavior of a given genome, which can be classified into the so-called Podospora spore killers or Psks (van der Gaag et al. 2000; Vogan et al. 2019). The Spok block stands out not only because of its size, typically around 150 kb, but also because there is otherwise high genome collinearity among strains of P. anserina and with the related species P. comata and P. pauciseta (Vogan et al. 2019).The fact that the Spok block is found at unique genomic positions between otherwise highly similar strains is of prime interest as each novel Spok block position creates a unique meiotic drive type (Psk) due to the intricacies of meiosis in Podospora (Vogan et al. 2019). We therefore set out to determine the mechanism through which the Spok block relocates throughout the genome. Additionally, we annotated the gene content of the various Spok blocks to describe their composition and understand what represents the minimal component of the Spok block. Lastly, we conducted fitness assays to investigate whether the presence of the Spok block imparts any detrimental effects upon the host. 相似文献
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Selnes OA 《The AIDS reader》2005,15(6):289-92, 294
Although the incidence of HIV-related dementia has decreased significantly in the era of contemporary HAART, the prevalence of memory and cognitive symptoms remains steady in persons with HIV/AIDS. Recognition of which memory symptoms may be specifically related to HIV infection is becoming more and more challenging because of the increased survival and aging of those living with HIV disease. Therefore, numerous age-related causes of memory impairment may need to be ruled out. Depression can often result in subjective memory symptoms but rarely causes objective cognitive impairment. Because of the widespread use of thiamine food supplementation, alcohol is now a less common cause of severe memory impairment. HAART remains the treatment of choice for HIV-related dementia. 相似文献
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Antioxidant levels were determined in five patients with the Lesch-Nyhan syndrome. The erythrocyte glutathione peroxidase activity was in average 1.8 times higher in Lesch-Nyhan patients than in controls (1.68 +/- 0.36 versus 0.92 +/- 0.17 mu kat/g hemoglobin, p less than 0.001). Plasma CuZn-superoxide dismutase activity was two times higher (p less than 0.001) and Mn-superoxide dismutase activity was 1.5 times higher (p less than 0.05) than in controls, whilst erythrocyte CuZn-superoxide dismutase, plasma extracellular-superoxide dismutase and lymphocyte superoxide dismutase did not differ between Lesch-Nyhan patients and healthy controls. These data might indicate that Lesch-Nyhan patients are exposed to a higher oxidative load than healthy control persons. 相似文献