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排序方式: 共有2471条查询结果,搜索用时 15 毫秒
51.
Mehta RH Harjai KJ Boura J O'Neill W Grines CL;Primary Angioplasty in Myocardial Infarction 《Journal of interventional cardiology》2005,18(3):149-154
Clinical and angiographic correlates of ischemia-driven target vessel revascularization (ITVR) in patients undergoing primary percutaneous coronary interventions (PCI) are currently less well known. Accordingly, we examined 2,981 patients enrolled in different Primary Angioplasty in Myocardial Infarction trials, who underwent primary PCI to evaluate risk factors and outcomes of individuals requiring subsequent ITVR. At 6 months, ITVR was required in 321 patients (11%). Compared to the cohort without ITVR, patients requiring ITVR were younger (P=0.036), females (P=0.018), and more likely to have systolic blood pressure >100 mmHg on presentation (P=0.022), family history of premature coronary artery disease (P=0.035), and postprocedure dissection (P=0.001). In contrast, Killip Class >I on presentation (P=0.05), left circumflex as infarct-related artery (P=0.022), and the use of ticlopidine (P=0.044) and stents (p=0.057) were less frequent among ITVR patients. Multivariate analysis identified younger age (for each 10-year decrease, odds ratio [OR], 1.18; 95% confidence interval [CI], 1.06-1.32), female gender (OR: 1.41, 95% CI: 1.05-1.89), and final dissection (OR: 1.69, 95% CI: 1.23-2.33) as independent risk factors for ITVR. In-hospital reinfarction (P < 0.001) was increased and at 6 months remained higher in ITVR patients; in-hospital and 6-month mortality did not differ between the two groups. Our study identifies the incidence, risk factors, and outcomes of patients requiring ITVR after primary PCI. Importantly, our data suggest that no increase in mortality occur, if ITVR is promptly performed to treat recurrent ischemia after primary PCI. 相似文献
52.
Over the years, lipids of non-pathogenic yeast such as Saccharomyces cerevisiae have been characterized to some details; however, a comparable situation does not exist for the human pathogenic fungi. This review is an attempt to bring in recent advances made in lipid research by employing high throughput lipidomic methods in terms of lipid analysis of pathogenic yeasts. Several pathogenic fungi exhibit multidrug resistance (MDR) which they acquire during the course of a treatment. Among the several causal factors, lipids by far have emerged as one of the critical contributors in the MDR acquisition in human pathogenic Candida. In this article, we have particularly focused on the role of lipids involved in cross talks between different cellular circuits that impact the acquisition of MDR in Candida. 相似文献
53.
Namita A. Sharma Alok Sharma Rajendra S. Garud 《Surgical and radiologic anatomy : SRA》2013,35(4):359-363
Variable arrangement of the visceral peritoneum would result in the formation of unexpected peritoneal bands and associated recesses. These could confound the unsuspecting clinician in both the diagnostic and therapeutic approach to the abdomen. It is thus imperative to be alert to the surprises the peritoneum may throw up and, however rare, abdominal conditions resulting from such aberrations must be kept in mind. Cadaveric dissection of an elderly female revealed a number of peritoneal anomalies. Apart from a cysto-duodenal extension of the lesser omentum, there was a bilaminar, avascular band passing from the inferior surface of the right lobe of liver to both the duodenum and the transverse colon. This anomalous band lay posterior to and distinct from the lesser omentum. The epiploic foramen was thus delimited by two unconventional folds. Further, the distal half of the transverse mesocolon failed to reach the posterior abdominal wall and instead formed an arched continuity with an aberrant mesentery of descending colon. An unusual type of peri-caecal recess was also present. 相似文献
54.
In long-term hamster bone marrow cultures, proliferation and differentiation of hemopoietic stem cells occurs for several months without need for hydrocortisone or adherent stromal elements, which are requirements for bone marrow growth in all other species studied. Only the most primitive erythroid progenitors (BFU-E) are produced in the cultures. Following treatment of the cells with erythropoietin, these progenitor cells undergo differentiation into mature hemoglobinized red blood cells. Concomitant addition of erythropoietin (Epo) and prostaglandin-E1 (PGE1) results in the production of large numbers of maturing red blood cells. In cultures stimulated with Epo and PGE1, as many as 70% of the cells are benzidine-positive, while Epo alone stimulated as many as 45% of the cells to become erythroid. Epo and PGE1 do not have any apparent deleterious effect on the continuous hemopoiesis occurring in these cultures. Under identical conditions, syngeneic adherent cell cultures do not produce any erythroid elements. The development of mature red blood cells from primitive erythroid precursors occurs in the presence of Epo alone and without any apparent need for adherent stromal elements. These cultures provide a useful in vitro model for dissecting the positive and negative signals that regulate erythropoiesis. 相似文献
55.
Fc gamma receptor II (CD32) on malignant B cells influences modulation induced by anti-CD19 monoclonal antibody 总被引:1,自引:1,他引:1
Vervoordeldonk SF; Merle PA; van Leeuwen EF; van der Schoot CE; von dem Borne AE; Slaper-Cortenbach IC 《Blood》1994,83(6):1632-1639
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies. 相似文献
56.
57.
Oliver Ziff Ibrahim Rajput Robert Adair Giles J Toogood K Rajendra Prasad J Peter A Lodge 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(3):212-219
Objective: A right and left hepatic trisectionectomy and an extended trisectionectomy are the largest liver resections performed for malignancy. This report analyses a series of 23 patients who had at least one repeat resection after a hepatic trisectionectomy for colorectal liver metastasis (CRLM).Methods: A retrospective analysis of a single-centre prospective liver resection database from May 1996 to April 2009 was used for patient identification. Full notes, radiology and patient reviews were analysed for a variety of factors with respect to survival.Results: Twenty-three patients underwent up to 3 repeat hepatic resections after 20 right and 3 left hepatic trisectionectomies. In 18 patients the initial surgery was an extended trisectionectomy. Overall 1-, 3- and 5-year survival rates after a repeat resection were 100%, 46% and 32%, respectively. No factors predictive for survival were identified.Conclusion: A repeat resection after a hepatic trisectionectomy for CRLM can offer extended survival and should be considered where appropriate. 相似文献
58.
Huizhen Wang Melissa Larson Albina Jablonka-Shariff Christopher A. Pearl William L. Miller P. Michael Conn Irving Boime T. Rajendra Kumar 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(15):5735-5740
FSH and luteinizing hormone (LH) are secreted constitutively or in pulses, respectively, from pituitary gonadotropes in many vertebrates, and regulate ovarian function. The molecular basis for this evolutionarily conserved gonadotropin-specific secretion pattern is not understood. Here, we show that the carboxyterminal heptapeptide in LH is a gonadotropin-sorting determinant in vivo that directs pulsatile secretion. FSH containing this heptapeptide enters the regulated pathway in gonadotropes of transgenic mice, and is released in response to gonadotropin-releasing hormone, similar to LH. FSH released from the LH secretory pathway rescued ovarian defects in Fshb-null mice as efficiently as constitutively secreted FSH. Interestingly, the rerouted FSH enhanced ovarian follicle survival, caused a dramatic increase in number of ovulations, and prolonged female reproductive lifespan. Furthermore, the rerouted FSH vastly improved the in vivo fertilization competency of eggs, their subsequent development in vitro and when transplanted, the ability to produce offspring. Our study demonstrates the feasibility to fine-tune the target tissue responses by modifying the intracellular trafficking and secretory fate of a pituitary trophic hormone. The approach to interconvert the secretory fate of proteins in vivo has pathophysiological significance, and could explain the etiology of several hormone hyperstimulation and resistance syndromes.During vertebrate evolution, the female reproductive pattern underwent a remarkable transition from spawning of large number of eggs in primitive species under favorable conditions to more tightly controlled ovarian cycles in higher vertebrates, such that only a limited number (rodents) or a single (human and nonhuman primates) egg is released per cycle (1, 2). Coincident with this event, the single pituitary gonadotropic hormone that exists in primitive vertebrates has given rise to two gonadotropins, FSH and luteinizing hormone (LH), which coordinate gametogenesis and steroidogenesis (3–7). FSH and LH are heterodimeric glycoproteins that contain a common α-subunit and a hormone-specific β-subunit (3). Although synthesized in the same cell, the gonadotrope, FSH is mostly constitutively released in many species, whereas LH is stored in dense core granules (DCGs) and secreted in pulses via the regulated pathway in response to gonadotropin-releasing hormone (GnRH) (8, 9). Although this pattern is evolutionarily conserved, how distinct modes of gonadotropin secretion affect ovarian development and target cell responses remain unclear. Although models in which variations in secretion of gonadotropins have been achieved in vivo (10) and in vitro, including basolateral and apically polarized secretion (11), the in vivo consequences of altered mode of gonadotropin trafficking and release (constitutive vs. regulated) from pituitary are untested. We sought to identify why the two gonadotropins, LH and FSH, expressed in the same pituitary cell have evolved to exit via different routes to regulate ovarian physiology. 相似文献
59.
Background
Cross-match-compatible platelets are used for the management of thrombocytopenic patients who are refractory to transfusions of randomly selected platelets. Data supporting the effectiveness of platelets that are compatible according to cross-matching with a modified antigen capture enzyme-linked immunosorbent assay (MAC-ELISA or MACE) are limited. This study aimed to determine the effectiveness of cross-match-compatible platelets in an unselected group of refractory patients.Materials and methods
One hundred ABO compatible single donor platelet transfusions given to 31 refractory patients were studied. Patients were defined to be refractory if their 24-hour corrected count increment (CCI) was <5×109/L following two consecutive platelet transfusions. Platelets were cross-matched by MACE and the CCI was determined to monitor the effectiveness of platelet transfusions.Results
The clinical sensitivity, specificity, positive predictive value and negative predictive value of the MACE-cross-matched platelets for post-transfusion CCI were 88%, 54.6%, 39.3% and 93.2%, respectively. The difference between adequate and inadequate post-transfusion 24-hour CCI for MACE cross-matched-compatible vs incompatible single donor platelet transfusions was statistically significant (p=0.000). The 24-hour CCI (mean±SD) was significantly higher for cross-match-compatible platelets (9,250±026.6) than for incompatible ones (6,757.94±2,656.5) (p<0.0001). Most of the incompatible cross-matches (73.2%) were due to anti-HLA antibodies, alone (55.3% of cases) or together with anti-platelet glycoprotein antibodies (17.9%).Discussion
The clinical sensitivity and negative predictive value of platelet cross-matching by MACE were high in this study and such tests may, therefore, be used to select compatible platelets for refractory patients. A high negative predictive value demonstrates the greater chance of an adequate response with cross-matched-compatible platelets. 相似文献60.
Mehta RH Parsons L Peterson ED;National Registry of Myocardial Infarction Investigators 《The American journal of cardiology》2012,109(7):925-931
Concern has been raised that Asian-Americans may have a higher bleeding risk than Caucasian-Americans when treated with fibrinolytic and antithrombotic agents. To date there is limited evidence to support or refute this hypothesis or evaluate bleeding risk and its related outcomes in Caucasian-Americans versus Asian-Americans with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary interventions (PPCI). We evaluated Asian-Americans and Caucasian-Americans with STEMI receiving reperfusion therapy in the National Registry of Myocardial Infarction (NRMI) 4 and 5 (n = 90,317). We studied risk-adjusted major bleeding and in-hospital mortality. Major bleeding rates after fibrinolysis were similar in Asian-Americans (n = 705) and Caucasian-Americans (n = 42,243, 11.1% vs 10.3%, adjusted odds ratio [OR] 0.97, 95% confidence interval [CI] 0.69 to 1.36, p = 0.5002). Although the observed major bleeding rate was higher in Asian-Americans (n = 1,037) compared to Caucasian-Americans (n = 46,332) treated with PPCI (10.3% vs 7.8%, p = 0.0036), these rates differed only marginally after adjusting for baseline clinical variables (OR 1.24, 95% CI 0.97 to 1.59). Overall adjusted mortality was similar in Asian-Americans and Caucasian-Americans when treated with fibrinolysis (OR 0.96, 95% CI 0.56 to 1.65) or with PPCI (OR 1.35, 95% CI 0.85 to 2.13). Major bleeding after PPCI or fibrinolysis was associated with similar increased risks for mortality in these ethic groups. In conclusion, despite suggestions to the contrary, Asian-Americans with STEMI treated with fibrinolysis or PPCI had similar bleeding and bleeding-related mortality risks compared to Caucasian-Americans. Given the genotypic and phenotypic differences between the 2 cohorts, similar studies in the rapidly growing Asian-American population are needed to confirm our findings and to understand the safety and effectiveness of newer potent antiplatelet and antithrombotic agents in patients with coronary syndromes. 相似文献