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71.
B-lymphocytes or B-cells form a diverse and flexible repertoire of immune cells that are reactive to almost all potential pathogens by means of the production of antigen-specific immunoglobulins. They can be divided into different populations or subsets, characterised by a distinct combination of properties. These subsets are identified on the base of their differentiation status (precursor B-cells, peripheral B-cells), their localisation in the micro-anatomical compartments of the B-cell follicle (marginal zone B-cells, lymphocytic corona B-cells, follicle centre B-cells), and the developmental lineage to which they belong (B-1 cells, and B-2 or conventional B-cells). The latter classification of B-cells into B-1 cells and B-2 cells is commonly followed by immunologists, mainly in the study of mice models, while pathologists and haematologists tend to use a terminology for B-cells which refers to their localisation in the micro-anatomical compartments of the B-cell follicle and/or differentiation status. In this review, we will discuss the various subsets of B-cells and point to the similarities between the various classification systems in use.  相似文献   
72.
Characterization of Sm13, a tegumental antigen of Schistosoma mansoni   总被引:2,自引:0,他引:2  
Sm13, a 13-kDa Schistosoma mansoni tegumental antigen, is one of the principal polypeptides recognized by antibodies from mice protectively vaccinated with adult-worm tegumental membranes. To obtain the complete gene encoding Sm13 we subcloned and sequenced a cDNA and a fragment of a genomic clone. The collated sequence contains 1088 nucleotides and represents the full-length open reading frame of the gene, encoding a protein of 104 amino acids with a calculated molecular mass of 11,923 Da, compatible with the native protein identified in the tegumental membranes. The sequence derived from genomic DNA contains a 45-nucleotide intron. The analysis of the predicted protein suggests the presence of both N- and C-terminal hydrophobic membrane-spanning segments, and the coding region contains no homology in the currently available data bases. Additionally, the coding region is preceded by putative CCAAT and TATA boxes that may be involved in the control of expression. Western-blot analysis and indirect immunofluorescence resulted in the identification of a 13-kDa protein (Sm13) in the tegument of adult worms. The present study reveals that Sm13 behaves as an integral membrane protein upon partitioning in Triton X-114 and that it is present in worms of 3 weeks or older but not in schistosomula or miracidia. Moreover, it is also specifically recognized by sera from some schistosomiasis patients in enzyme-linked immunosorbent assay and Western-blot analysis, suggesting that it is immunogenic in human schistosomiasis. Received: 17 February 2000 / Accepted: 22 March 2000  相似文献   
73.
One of the early diamond crimped knitted polyester (Dacron) grafts was surgically excised after implantation for 25 years in the aorto-billiac position because of false aneurysm formation at the three anastomotic sites. The sutures were no longer visible. While the areas around the false aneurysm were poorly incorporated, the graft limbs were well encapsulated with some endothelial-like cells on the luminal surface. The integrity of the graft was well preserved despite mild fraying and the disruption of one stitch.  相似文献   
74.
Quality of Life Research - Illness cognitions regarding helplessness and acceptance are known to play a role in health-related quality of life (HRQoL). Our study examined the evolution of these...  相似文献   
75.
The aim of this study was to explore the impact of bariatric surgery on fat and sweet taste perceptions and to determine the possible correlations with gut appetite-regulating peptides and subjective food sensations. Women suffering from severe obesity (BMI > 35 kg/m2) were studied 2 weeks before and 6 months after a vertical sleeve gastrectomy (VSG, n = 32) or a Roux-en-Y gastric bypass (RYGB, n = 12). Linoleic acid (LA) and sucrose perception thresholds were determined using the three-alternative forced-choice procedure, gut hormones were assayed before and after a test meal and subjective changes in oral food sensations were self-reported using a standardized questionnaire. Despite a global positive effect of both surgeries on the reported gustatory sensations, a change in the taste sensitivity was only found after RYGB for LA. However, the fat and sweet taste perceptions were not homogenous between patients who underwent the same surgery procedure, suggesting the existence of two subgroups: patients with and without taste improvement. These gustatory changes were not correlated to the surgery-mediated modifications of the main gut appetite-regulating hormones. Collectively these data highlight the complexity of relationships between bariatric surgery and taste sensitivity and suggest that VSG and RYGB might impact the fatty taste perception differently.  相似文献   
76.
A Coronavirus Disease 2019 (COVID-19)–specific Hospital-at-Home was implemented in a 400-bed tertiary hospital in Barcelona, Spain. Senior or immune-compromised physicians oversaw patient care. The alternative to inpatient care more than doubled beds available for hospitalization and decreased the risk of transmission among patients and health care professionals. Mild cases from either the emergency department or after hospital discharge were deemed suitable for admission to the Hospital-at-Home. More than half of all patients had pneumonia. Standardized protocols and management criteria were provided. Only 6% of cases required referral for inpatient hospitalization. These results are promising and may provide valuable insight for centers undertaking Hospital-at-Home initiatives or in the case of new COVID-19 outbreaks.  相似文献   
77.
Lasers in Medical Science - The aim of the present study was to investigate the effects of photobiomodulation (PBM) therapy on the expression of heat shock protein 70 (HSP70) and tissue repair in...  相似文献   
78.
79.
Enhanced Recovery After Surgery (ERAS) constitutes the application of a series of perioperative measures based on the evidence, in order to achieve a better recovery of the patient and a decrease of the complications and the mortality. These ERAS programs initially proved their advantages in the field of colorectal surgery being progressively adopted by other surgical areas within the general surgery and other surgical specialties. The main excluding factor for the application of such programs has been the urgent clinical presentation, which has caused that despite the large volume of existing literature on ERAS in elective surgery, there are few studies that have investigated the effectiveness of these programs in surgical patients in emergencies. The aim of this article is to show ERAS measures currently available according to the existing evidence for emergency surgery.  相似文献   
80.
BackgroundPeptide receptor radionuclide therapy is a targeted therapy used to treat unresectable somatostatin receptor-positive neuroendocrine tumors. The objective of this study was to evaluate response rates among neuroendocrine tumors of different primaries and identify factors relevant to future treatment strategies.MethodsWe retrospectively reviewed patients who received peptide receptor radionuclide therapy for neuroendocrine tumors from 2018 to 2019 at our institution. Patients were assessed with computed tomography/magnetic resonance imaging and 68Ga-DOTATATE-positron emission tomography before and after 2 or 4 cycles of peptide receptor radionuclide therapy. Tumor response was evaluated by RECIST 1.1. Statistics included multinomial logistic regression models and Fisher exact test.ResultsTwenty-seven patients underwent 92 cycles of peptide receptor radionuclide therapy: pancreas (n = 11), small bowel (n = 7), and other (n = 9) neuroendocrine tumors. Overall, 30% (8 of 27) had partial response, 59% (16 of 27) stable disease, and 11% (3 of 27) progressed. Pancreatic neuroendocrine tumors responded differently from small bowel neuroendocrine tumors regardless of cycle number (P = .01). The majority of pancreatic neuroendocrine tumors (6 of 11) had partial response to peptide receptor radionuclide therapy, while all small bowel neuroendocrine tumors had stable disease. Pancreatic neuroendocrine tumors stable after 2 cycles were more likely to respond to additional cycles versus other neuroendocrine tumors (probability: 60% vs 11%).ConclusionPatients with unresectable advanced or metastatic pancreatic neuroendocrine tumors may benefit from a full course of peptide receptor radionuclide therapy, whereas other neuroendocrine tumors appear less likely to respond. Large prospective studies are needed to confirm these findings.  相似文献   
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