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排序方式: 共有2479条查询结果,搜索用时 31 毫秒
1.
Nephronophthisis related to homozygous NPHP1 gene deletion as a cause of chronic renal failure in adults. 总被引:1,自引:0,他引:1
2.
Fady K. Baddoura Isam W. Nasr Barbara Wrobel Qi Li Nancy H. Ruddle Fadi G. Lakkis 《American journal of transplantation》2005,5(3):510-516
Lymphoid neogenesis is the process by which ectopic lymphoid accumulations that resemble lymph nodes arise in nonlymphoid tissues. Such lymphoid accumulations, known as tertiary lymphoid organs (TLO), are observed in chronic autoimmunity and they propagate immune pathology by setting up local antigen presenting sites. Whether lymphoid neogenesis occurs in transplanted organs and contributes to rejection is not well understood. To begin to address this question, we retrospectively analyzed 319 murine cardiac allografts for microscopic evidence of lymph-node-like structures. We found 78 allografts that had either classical TLO, characterized by discrete T- and B-cell zones and high endothelial venules (HEV) expressing peripheral node addressin (PNAd) (n = 34), or PNAd(+) HEV without organized lymphoid accumulations (n = 44). These changes were present in both short- and long-lived allografts and were invariably associated with rejection. Importantly, they occurred in 78% of allografts undergoing chronic rejection (n = 85) but in only 7% of allografts undergoing primarily acute rejection (n = 184). These findings indicate that, like autoimmunity, alloimmunity is associated with lymphoid neogenesis in the target organ and suggest a role for local T-cell activation in chronic allograft rejection. 相似文献
3.
M Ben Farhat H Boussadia I Gandjbakhch H Mzali A Chouaieb M Ayari K Ben Salah 《The Journal of thoracic and cardiovascular surgery》1990,99(4):639-644
Controversy persists regarding whether the efficacy of closed instrumental mitral commissurotomy compares well enough with that of open commissurotomy to warrant its continued use. The purpose of this study was to compare the results of operation as determined by catheterization studies in 63 patients with pure, severe, and noncalcified mitral stenosis. The patients were randomly assigned to one of two groups: thirty-two patients were operated on by the closed technique (group I) and 31 by the open technique (group II). All patients underwent left-sided and right-sided catheterization before and 4 months after operation. Preoperatively the two groups were statistically similar with regard to major clinical data and hemodynamic findings. There were no deaths at operation or systemic embolism in the two groups. The prevalence of surgically induced mitral regurgitation was similar in the two groups (12.4% versus 12.9%). Pulmonary arterial pressure and arteriolar and total pulmonary vascular resistance decreased significantly in the two groups. Pulmonary capillary wedge pressure decreased from 23.3 +/- 8.5 to 15.8 +/- 7 mm Hg in group I (p less than 0.001) and from 23.7 +/- 6 to 14 +/- 5.8 mm Hg in group II (p less than 0.001). Cardiac index increased from 2.86 +/- 0.84 to 3.14 +/- 0.78 L/min/m2 in group I, but this increase did not reach statistical significance. In group II cardiac index increased from 2.89 +/- 0.6 to 3.6 +/- 0.6 L/min/m2 (p less than 0.005). The mean and end-diastolic transmitral pressure gradients decreased significantly in the two groups, but the decrease was statistically greater in the open mitral commissurotomy group (p less than 0.001). Mitral valve area increased from 0.82 +/- 0.18 to 1.4 +/- 0.40 cm2 in group I (p less than 0.01) and from 0.84 +/- 0.15 to 2.14 +/- 0.53 cm2 in group II (p less than 0.001). The mean increase in mitral valve area was 0.61 cm2 in group I and 1.34 cm2 in group II (p less than 0.001). At exercise, in patients with resting pulmonary capillary wedge pressures of 18 mm Hg or less, cardiac index increased by 36% in group I (23 patients) and 48% in group II (24 patients), because of a smaller mitral valve area in group I (1.61 +/- 0.39 cm2) than in group II (2.45 +/- 0.65 cm2). Thus open commissurotomy improved hemodynamic values to a greater extent than closed commissurotomy at both rest and exercise.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
4.
A wide variety of health care options--home-based, indigenous, and cosmopolitan--exists in northern Balochistan, Pakistan. This paper examines health-seeking behavior in the area of mother and child health for villagers in this pluralistic medical setting. The analysis of a specific series of illness episodes shows that the majority of cases obtain treatment from different medical systems for a single episode. Interest in medications takes precedence over practitioners, and the meaning the villagers attach to such substances is explored. Long-established patterns of behavior relating to indigenous medicine continue to occur when cosmopolitan medicine is utilized. Information presented here helps to explain problems in utilization of cosmopolitan pharmaceuticals and delineates areas for future health programme activity. 相似文献
5.
Fadi Sleilati 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(9):1003-1005
A new technique for earlobe reconstruction is described, illustrated by a case report. This technique uses double-crossed skin flaps from the pre-auricular and retromandibular areas. No skin grafts and no cartilage framework are needed. This technique is particularly indicated for immediate earlobe reconstruction. 相似文献
6.
C3d binding to the circumsporozoite protein carboxy-terminus deviates immunity against malaria 总被引:5,自引:0,他引:5
Bergmann-Leitner ES Scheiblhofer S Weiss R Duncan EH Leitner WW Chen D Angov E Khan F Williams JL Winter DB Thalhamer J Lyon JA Tsokos GC 《International immunology》2005,17(3):245-255
The immunogenicity of recombinant protein or anti-viral DNA vaccines can be significantly improved by the addition of tandem copies of the complement fragment C3d. We sought to determine if the efficacy of a circumsporozoite protein (CSP)-based DNA vaccine delivered to mouse skin by gene gun was improved by using this strategy. Instead, we found that C3d suppressed the protective immunity against Plasmodium berghei malaria infection and deviated immunity, most notably by suppressing the induction of antibodies specific for the CSP C-terminal flanking sequence and by suppressing the induction of CSP-specific IL-4-producing spleen cells. We further showed that C3d bound to the C-terminal flanking sequence of the CSP, which may explain the immune deviation observed in CS/C3d chimeric antigen. We have thus identified C3d-mediated epitope masking and shifting of both the humoral and cellular immune responses as a potential novel escape mechanism, which plasmodia may use to divert the induction of protective immunity. 相似文献
7.
Teodoro WR Velosa AP Witzel SS Garippo AL Farhat C Parra ER Sonohara S Capelozzi VL Yoshinari NH 《Pathology, research and practice》2004,200(10):681-691
The pathogenesis of diffuse connective tissue diseases (DCTD) is still unknown and has been extensively studied regarding its autoimmunity aspects related to extracellular matrix (ECM) remodelling, with an emphasis on the collagens at the inflammatory site. The present paper describes the pulmonary architectural and repair/remodelling responses to injury after immunization of rabbits with human type V collagen. The animal model consisted of rabbits immunized with collagen mixed with Freund's adjuvant and sacrificed 7, 15, 30, 75, and 120 days after the first of four doses of antigen. Pulmonary architecture remodelling response was evaluated by histology, morphometry, and the immunofluorescence method, according to compartments of reference (parenchyma and interstitium) and injury: 1 inflammation (polymorphonuclear and mononuclear cells); 2-repair (fibrosis) and 3-ECM remodelling (collagen system). The results showed an intense inflammatory involvement of the pulmonary vascular and bronchiolar parenchyma, characterized by increased wall thickness in small arteries, infiltrations by pseudoeosinophils, and mononuclear cells. Progressive remodelling of the pulmonary ECM was characterized by collagen deposition in the septal and bronchovascular interstitium, especially in rabbits sacrifices at 75 and 120 days. The ECM remodelling process was not reproduced when rabbits were inoculated with collagen types I and III. We conclude that the model reproduces morphologic changes similar to those observed in many DCTD, encouraging realization of other experiments to gain a better understanding of the pathogenesis of these diseases. 相似文献
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10.
Nebulization of aqueous solutions is a convenient delivery system to deliver drugs to the lungs because it can produce droplets small enough to reach the alveolar region. However, the droplet size might be affected by the changes in the temperature and the concentration of the nebulizing solution in the reservoir during nebulization. In this study, the changes in the droplet size over the nebulization time using a PariBoy air-jet and a Multisonic ultrasonic nebulizer have been studied. The findings were related to changes in the temperature, concentration, surface tension, viscosity and saturated vapour pressure of the nebulizing solution. By using the jet nebulizer, an increase in the droplet size followed by a decrease has been observed. This observation could be attributed to the approx. 7 degrees C reduction of the temperature during the first 2 min in the jet nebulizer reservoir which increased the viscosity of the nebulizing solution. After this initial period of time, the increasing drug concentration induced a reduction of the surface tension and, consequently, a decrease in the droplet size. However, with the ultrasonic nebulizer a temperature increase of approx. 20 degrees C during the first 6 min in the nebulizing solution was observed leading to a decrease in droplet size, viscosity and surface tension and an increasing saturated vapour pressure. This again led to smaller average droplet sizes. 相似文献