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21.
The authors present a case of intramural hematoma of the small intestines during anticoagulant treatment. With reference to this case, they study the frequency, etiopathogenesis and anatomy of this hematoma and particularly look at the radiological manifestations. In this respect they distinguish three stages in the evolution. The first, when the straight X-ray of the abdomen and barium followthrough demonstrate an axial stenosis of the small intestines with dilation of the proximal loops; the second (between the 7th and 20th days) when the loop affected by the hematoma takes on a characteristic "palissade" or "spring" -like sausage appearance; finally the third (after the 3rd week), when only thickening of the haustrations persists with progressive return to normal. The radiological diagnosis is discussed, not only with intramural hematomas of the small intestines of other etiologies (traumatic, during pancreatitis, during disorders in hemostatis), but also with conditions giving rise to similar radiological pictures: malabsorption, inflammatory conditions, etc.  相似文献   
22.
The spike (S) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) facilitates viral entry into host cells and is the key target for neutralizing antibodies. The SARS-CoV-2 lineage B.1.620 carries fifteen mutations in the S protein and is spread in Africa, the US and Europe, while lineage R.1 harbors four mutations in S and infections were observed in several countries, particularly Japan and the US. However, the impact of the mutations in B.1.620 and R.1 S proteins on antibody-mediated neutralization and host cell entry are largely unknown. Here, we report that these mutations are compatible with robust ACE2 binding and entry into cell lines, and they markedly reduce neutralization by vaccine-induced antibodies. Our results reveal evasion of neutralizing antibodies by B.1.620 and R.1, which might have contributed to the spread of these lineages.  相似文献   
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AIDS and Behavior - In this mixed-methods study, we examine the relationship between provider communication and patient health literacy on HIV continuum of care outcomes among women living with HIV...  相似文献   
27.
Leo A  Kreft H  Hack H  Kempf T  Roelcke D 《Vox sanguinis》2004,86(2):141-147
BACKGROUND AND OBJECTIVES: In cold agglutinin disease, monoclonal red blood cell autoantibodies, termed cold agglutinins, induce haemolysis in patients exposed to the cold. Commonly, these autoantibodies are directed against the developmentally regulated I/i blood groups. A second blood group system, the Pr system (located on glycophorins), is involved less frequently. Anti-Pr cold agglutinins recognize either alpha 2,3- or alpha 2,6-linked N-acetylneuraminic acid as the immunodominant group. Cold agglutinins of anti-I/i specificity show a remarkable restriction in their genomic repertoire of the immunoglobulin heavy and light-chain immunoglobulin-variable domain (i.e. exclusive use of VH4-34 in heavy chains). For anti-Pr cold agglutinins, preliminary data on the repertoire of the light-chain variable domain indicate a preference for the subgroup Vkappa IV. To elucidate restrictions in the light-chain variable-domain subgroup repertoire of anti-Pr cold agglutinins systematically, and to discuss these results in the context of their anti-Pr(1-3) subclassification and immunodominant sialic acid, light chains in 13 anti-Pr cold agglutinins were investigated. MATERIALS AND METHODS: The anti-Pr light chains were isolated using temperature-dependent absorption/elution techniques. Subsequently, they were subjected to N-terminal Edman degradation, and the light chain Vkappa subgroup was affiliated using the Kabat database. RESULTS: Five of 13 (38%) light chains belonged to Vkappa IV, five of 13 (38%) to Vkappa I and three of 13 (23%) to Vkappa III. Anti-Pr with Vkappa IV subgroup light chains exclusively recognized alpha 2,3-linked N-acetylneuraminic acid. CONCLUSIONS: Including data from the literature, the repertoire of the light-chain variable domain in pathological anti-Pr cold agglutinins exhibits a clear bias towards the use of the single germline gene-derived subgroup, Vkappa IV (eight of 17 or 47%). The association of Vkappa IV subgroup light chain-containing anti-Pr cold agglutinins with binding to alpha 2,3-, but not alpha 2,6-linked N-acetyneuraminic acid raises speculations about a possible role of subgroup-derived determinants in anti-Pr binding.  相似文献   
28.
Bowen  BJ; Morgan  EH 《Blood》1987,70(1):38-44
The mechanisms underlying the impaired utilization of transferrin-bound iron by erythroid cells in the anemia of the Belgrade laboratory rat were investigated using reticulocytes from homozygous anemic animals and transferrin labeled with 59Fe and 125I. The results were compared with those obtained using reticulocytes from phenylhydrazine-treated rats and iron-deficient rats. Each step in the iron uptake mechanism was investigated, ie, transferrin-receptor interaction, transferrin endocytosis, iron release from transferrin, and transferrin exocytosis. Although there were quantitative differences, no fundamental difference was found in any of the abovementioned aspects of cellular function when the reticulocytes from Belgrade rats were compared with those from iron-deficient animals. The basic defect in the Belgrade reticulocytes must therefore reside in subsequent steps in iron uptake, after it is released from transferrin within endocytotic vesicles, ie, in the mechanism by which it is transferred across the lining membrane of the vesicles into the cell cytosol. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of reticulocyte ghosts extracts demonstrated a prominent protein band of mol wt 69,000 that was absent or present only in low concentration extracts from the other two types of reticulocytes. This may be a result of the genetic defect.  相似文献   
29.

Introduction

Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.

Methods

A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.

Results

From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.

Conclusions

The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay.  相似文献   
30.
Woods  VL Jr; Oh  EH; Mason  D; McMillan  R 《Blood》1984,63(2):368-375
Chronic idiopathic thrombocytopenic purpura (ITP) is caused by an antibody reactive with platelet-associated antigens. The present studies provide direct evidence that some patients with chronic ITP have autoantibodies against the platelet glycoprotein (GP) IIb/IIIa complex. Microtiter wells, coated with a monoclonal antibody (2G12) specific for GPIIb/GPIIIa were reacted with GPIIb/GPIIIa contained in a platelet extract. Control wells containing the same antibody were reacted with a cell extract containing no GPIIb/GPIIIa. After washing, the wells were reacted with patient or control plasma, and IgG binding was detected using 125I-Fab2-anti-human IgG. Assay values were expressed as binding ratios (cpm GPIIb/GPIIIa wells/cpm control wells). Plasma from 5 of 56 patients with chronic ITP had ratios (1.36-3.14) greater than 3 standard deviations above the mean (+/- SD) of control plasmas--0.93 +/- 0.12. Elevated values were also noted in two patients with anti-P1A1 antibody (ratios greater than 30) and in one patient with Hodgkin's disease and an ITP-like syndrome (ratio 1.53). Normal values were noted in 34 patients with a variety of immune and nonimmune diseases. Plasma from two of the positive ITP patients was reacted with 125I-surface-labeled platelets and, after solubilization, the IgG and bound antigen were precipitated with Staph-A. Autoradiographs from SDS- PAGE electrophoresis of the Staph-A-bound proteins shows two radioactive bands consistent in size with GPIIb and GPIIIa.  相似文献   
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