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排序方式: 共有783条查询结果,搜索用时 15 毫秒
1.
Dan Azagury Tara E Mokhtari Luis Garcia Ulysses S Rosas Trit Garg Homero Rivas John Morton 《Surgery》2019,165(3):565-570
Background
Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.Methods
A total of 1,331 consecutive patients at a single academic institution were reviewed from a prospectively collected database. Preoperative data collected included demographics, body mass index, and percent excess weight loss. Postoperative BMI and %EWL were collected at 12, 24, and 36 months. Percent excess weight loss was analyzed by the percentiles of excess weight lost, and the distribution of percent excess weight loss was evaluated in 10% increments. Lack of a successful treatment effect was defined as <25% excess weight loss.Results
Of the 1,331 patients, 72.4% (963) underwent laparoscopic Roux-en-Y gastric bypass, 18.3% (243) laparoscopic sleeve gastrectomy, and 9.4%(125) laparoscopic adjustable gastric banding. Mean percent excess weight loss was greatest for laparoscopic Roux-en-Y gastric bypass, followed by laparoscopic sleeve gastrectomy, and then by laparoscopic adjustable gastric banding at every time point: at 2 years mean percent excess weight loss was 77.9± 24.4 for laparoscopic Roux-en-Y gastric bypass, 50.8 ± 25.8 for laparoscopic sleeve gastrectomy, and 40.8± 25.9 for laparoscopic adjustable gastric banding (P < .0001). The rates of a successful treatment effect s for laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding were 0.9%, 5.2%, and 24.3% at 1 year; 0.3%, 11.1%, and 26.0% at 2 years; and 1.0%, 25.3%, and 30.2% at 3 years. At 1 year, the odds ratio of lack of a successful treatment effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass was 6.305 (2.125–19.08; P?=?.0004), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass was 36.552 (15.64–95.71; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy was 5.791 (2.519–14.599; P < .0001). At 2 years, the odds ratio for laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass increased to 70.7 (9.4–531.7; P < .0001), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass increased to 128.1 (16.8–974.3; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy decreased to 1.8 (0.9–3.6; P?=?.09).Conclusion
This study emphasizes the existing variability in weight loss across bariatric procedures as well as in the lack of a treatment effect for each procedure. Although laparoscopic adjustable gastric banding has the greatest rate of a lack of a successful treatment effect, the rate remained stable over 3 years postoperatively. Laparoscopic sleeve gastrectomy showed a doubling in the rate of a lack of a successful treatment effect every year reaching 25% at year 3. The rates for lack of a successful treatment effect for laparoscopic Roux-en-Y gastric bypass remained stable at about 1% for the first 3 years postoperatively. 相似文献2.
Sabrina Benedetto Roberta Pulito Simonetta Geninatti Crich Guido Tarone Silvio Aime Lorenzo Silengo Jrg Hamm 《Magnetic resonance in medicine》2006,56(4):711-716
Targeted imaging requires site-specific accumulation of a contrast agent (CA), and the properties of that agent must be selected according to the abundance of the target to obtain a signal above the detection limit of the instrument. However, numerical estimates of receptors per cell are rarely found in the literature. Integrin receptors would be particularly promising targets because of their accessibility from the blood stream and expression on activated neovascular endothelial cells. We systematically estimated the number of integrin receptors of cell lines and primary cells by flow cytometry analysis. Since integrin receptors are heterodimeric molecules, and alpha(v) forms complexes with various beta subunits, the numbers of alpha(v) and beta(3) subunits are therefore dissimilar. The observed values are 3 . 10(3)-1.4 . 10(4)/cell for alpha(v), and 5.3 . 10(2)-1.1 . 10(4)/cell for beta(3). Despite the low number of exposed receptors, we show that up to single-cell MR visualization can be achieved with the use of iron oxide beads complexed with antibodies as CAs. 相似文献
3.
Urban Sester Barbara C. Gärtner Heinrike Wilkens Bernhard Schwaab Rolf Wössner Ingrid Kindermann Matthias Girndt reas Meyerhans Nikolaus Mueller-Lantzsch Hans-Joachim Schäfers Gerhard W. Sybrecht Hans Köhler Martina Sester 《American journal of transplantation》2005,5(6):1483-1489
Patients after kidney, heart and lung transplantation differ in their immunosuppressive drug regimens and in susceptibility to infectious complications with cytomegalovirus (CMV). In this study, CMV-specific T-cell responses were characterized in long-term transplant recipients and associated with the frequency of infectious complications. CMV-reactive CD4 T cells from 50 healthy controls, 68 renal, 14 heart and 24 lung transplant recipients were flow cytometrically quantified by the induction of cytokines after specific stimulation. Moreover, the immunosuppressive effect of calcineurin inhibitors on specific T-cell reactivity was quantified in vitro and compared with responses in vivo. Median CMV-specific T-cell frequencies in long-term renal (1.48%; range 0.06-17.26%) and heart transplant recipients (0.90%; 0.13-12.49%) did not differ from controls (1.82%; 0.26-21.00%). In contrast, CMV-specific T-cell levels were significantly lower in lung transplant recipients (0.50%; <0.05-4.98%) and showed a significant correlation with the frequency of infectious episodes (r =-0.57, p = 0.005). The differences within the groups were associated with increasing dosages of immunosuppressive drugs, as exemplified for calcineurin inhibitors that dose dependently reduced specific T-cell reactivity in vitro. In conclusion, monitoring CMV-specific CD4 T cells may serve as a measure for long-term disease susceptibility and may contribute to an improved management of CMV complications after lung transplantation. 相似文献
4.
Monoclonal antibodies against human granulocytes and myeloid differentiation antigens 总被引:4,自引:0,他引:4
Patrice Mannoni Anna Janowska-Wieczorek A. Robert Turner Locksley McGann Jean-Michael Turc 《Human immunology》1982,5(4):309-323
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis. 相似文献
5.
人体恶性实体瘤TIL增殖力、表型和杀伤力研究 总被引:4,自引:0,他引:4
在建立高活力肿瘤浸润淋巴细胞(TIL)分离培养方法的基础上,对83例恶性实体瘤TIL的细胞增殖动力学、部份TIL表型与杀伤力等作了较为系统的研究。结果提示,本实验室所建立分离培养的TIL增殖能力较强且稳定,有65%的增殖倍数大于1000倍;3H-TdR掺入高峰在培养的第45~75天;对其自身的原代肿瘤细胞杀伤力可以维持至56天以上;对56份经rIL2诱导的TIL(培养时间17±5.2天)表型分析:CD380±21%,CD437±21%,CD844±18%,HLADR69±24%,与rIL2诱导前比较,CD3、CD4、CD8和HLADR均增多,尤以CD3与CD8表型增多明显。 相似文献
6.
Jak-3 is a non-receptor tyrosine kinase that plays an important role in coordinating signals received through a wide range of cytokine receptors, including the IL-7 receptor (IL-7R). Jak-3-deficient mice have a profound block in B cell development at the pro-to-pre-B cell transition and have very few peripheral B cells. This block has been postulated to reflect the inability of Jak-3(-/-) pro-B cells to respond to IL-7. Here we demonstrate that B cell development can be partially restored in Jak-3-deficient mice when they are bred to mice carrying both a rearranged Ig heavy chain (IgH/Igmu) transgene and a c-myc transgene expressed in the B cell lineage. Jak-3(-/-) mice expressing both of these transgenes exhibit significant increases in the number of B cells in the bone marrow and, to a lesser extent, in the spleen. However, very few rescued B cells were detectable in mice greater than 4 months of age. To determine whether resident hyperactivated Jak-3(-/-) peripheral T cells are responsible for the elimination of the rescued B cells in older mice, we bred IgH transgenic (Igmu Tg)/myc Tg/Jak-3(-/-) mice to T cell-deficient (TCRalpha(-/-)) mice. Data from these experiments suggest that the paucity of B cells in older Jak-3(-/-) mice is largely attributable to the lack of Jak-3 in the B cells themselves. Thus, Jak-3 seems to play several important roles in B cells: during development, to enable cell division, Ig gene rearrangement and cell differentiation, and in mature cells, to promote B cell survival in the periphery. 相似文献
7.
We have developed a highly sensitive cytolysis test, the fluorolysis assay, as a simple nonradioactive and inexpensive alternative to the standard 51Cr-release assay. P815 cells were stably transfected with a plasmid expressing the enhanced green fluorescent protein (EGFP) gene. These target cells were coated with or without cognate peptide or anti-CD3 Ab and then incubated with CD8(+) T cells to allow antigen-specific or nonspecific lysis. The degree of target cell lysis was measured using flow cytometry to count the percentage of viable propidium iodide(-) EGFP(+) cells, whose numbers were standardized to a reference number of fluorochrome-linked beads. By using small numbers of target cells (200-800 per reaction) and extended incubation times (up to 2 days), the antigen-specific cytolytic activity of one to two activated CD8(+) T cells of a CTL line could be detected. The redirected fluorolysis assay also measured the activity of very few (> or =6) primary CD8(+) T cells following polyclonal activation. Importantly, antigen-specific lysis by small numbers (> or =25) of primary CD8(+) T cells could be directly measured ex vivo. This exquisite sensitivity of the fluorolysis assay, which was at least 8-33-folds higher than an optimized 51Cr-release assay, allows in vitro and ex vivo studies of immune responses that would otherwise not be possible due to low CTL numbers or frequencies. 相似文献
8.
Chemically induced mutants of an I-Ak,d expressing antigen-presenting B-cell--B-lymphoma hybridoma have recently been generated by immunoselection in vitro and were found to possess alterations in some of their serologically and functionally defined I-Ak region dependent functions. In order to identify at the structural level the origin of the differences in serological and functional properties of these mutants, I-Ak molecules from several of these mutant hybridomas were compared biochemically to wild-type I-Ak polypeptides by two-dimensional gel electrophoresis and high-pressure liquid chromatographic tryptic peptide analyses. Two-dimensional gel electrophoresis indicated that no major structural alterations, resulting in changes in mol. wt or charge, had occurred in the Ak alpha or Ak beta polypeptides from the mutant cells. Likewise, Ak alpha peptide maps of the mutants were indistinguishable from the normal Ak alpha peptide maps. However, two of the three mutants studied did exhibit one additional peptide in their Ak beta peptide maps. These results suggest that the major deficiencies in T-cell-activating functions of these mutants are a result of a limited alteration in the Ak beta polypeptide primary structure. 相似文献
9.
Poapolathep A Nagata T Suzuki H Kumagai S Doi K 《Experimental and molecular pathology》2003,75(1):74-79
Development of early apoptosis and changes in lymphocyte subsets were examined in lymphoid organs of female BALB/c mice after oral administration of 15 mg/kg b.w. of nivalenol (NIV), the major type B trichothecene mycotoxin, by FACS analysis. Judging from the results of viable cell count and apoptotic cell index, NIV attacked Peyer's patches first and thymus most severely. In thymus, selective damage in CD4(+)CD8(+) cells was observed at 12 and 24 h after inoculation (HAI), following the peak of apoptosis at 9 HAI. CD4(+) cells were clearly suppressed at 3 HAI in Peyer's patches, at and after 9 HAI in mesenteric lymph nodes, and 3 to 12 HAI in spleen, respectively. CD8(+) cells were also suppressed at 24 HAI in mesenteric lymph nodes and at 12 HAI in spleen, respectively. As to changes in B cell subsets, IgG(+) cells significantly decreased from 3 to 12 HAI and all B cell subsets at 24 HAI in mesenteric lymph nodes. In spleen, IgM(+) cells were suppressed at 9 HAI. On the other hand, in Peyer's patches, following clear decrease in the numbers of pan-T and pan-B cells and viable cells at 3 HAI, all B cell subsets, especially IgA(+) cells, showed a significant increase in their numbers at 9 HAI, and the numbers of IgA(+) and IgM(+) cells remained higher values than controls thereafter. Taken together, in the course of recovery from NIV-induced prominent damage in Peyer's patches at 3 HAI, interaction of NIV with Peyer's patches might result in in vivo stimulation of interleukin production at this site and result in increased proliferation and differentiation of IgA-secreting B cells at and after 9 HAI. 相似文献
10.
A Ohara T Suda N Tokuyama J Suda K Nakayama Y Miura S Nishikawa H Nakauchi 《International immunology》1991,3(7):703-709
The first stages of the pathway by which lymphocytes differentiate from hemopoietic stem cells were studied at a clonal level. When 211 interleukin 3 (IL-3)-induced blast colonies shown to be capable of differentiating into a variety of hemopoietic cells were individually transferred into wells containing a monolayer of stromal cells, growth in granulocyte, macrophage, megakaryocyte, or mast cell lineages was observed in 192 wells. In seven of these 192 wells, lymphoid cell growth also was seen. The lymphoid cells were proved to be B lymphocytes by phenotype and immunoglobulin gene rearrangement analyses and by demonstration of surface expression of IgM. The clonal origin of myeloid and B lymphocyte lineage cells was further confirmed by the generation of both myeloid and B lymphoid cells in the same well following FACS clone-sorting of IL-3 induced blast cells. These results provide in vitro evidence that cells of B lymphoid and myeloid lineage can originate clonally from single primitive hemopoietic stem cells. 相似文献