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A retrospective study was carried out on 40 children from Saudi Arabia with Henoch-Sch?nlein syndrome to delineate its clinical pattern. More than 50 per cent of the cases occurred in winter. There was no apparent causal relationship with B-haemolytic streptococcal infection. All patients had skin rash. Fifty-eight per cent had gastrointestinal manifestations, 58 per cent had joint manifestations and 38 per cent had renal manifestations. The main clinical features of Henoch-Sch?nlein syndrome in Saudi children are comparable to those reported elsewhere.  相似文献   
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Evidence for the involvement of a Bemisia tabaci GroEL homologue in the transmission of tomato yellow leaf curl geminivirus (TYLCV) is presented. A approximately 63-kDa protein was identified in B. tabaci whole-body extracts using an antiserum raised against aphid Buchnera GroEL. The GroEL homologue was immunolocalized to a coccoid-shaped whitefly endosymbiont. The 30 N-terminal amino acids of the whitefly GroEL homologue showed 80% homology with that from different aphid species and GroEL from Escherichia coli. Purified GroEL from B. tabaci exhibited ultrastructural similarities to that of the endosymbiont from aphids and E. coli. In vitro ligand assays showed that tomato yellow leaf curl virus (TYLCV) particles displayed a specific affinity for the B. tabaci 63-kDa GroEL homologue. Feeding whiteflies anti-Buchnera GroEL antiserum before the acquisition of virions reduced TYLCV transmission to tomato test plants by >80%. In the haemolymph of these whiteflies, TYLCV DNA was reduced to amounts below the threshold of detection by Southern blot hybridization. Active antibodies were recovered from the insect haemolymph suggesting that by complexing the GoEL homologue, the antibody disturbed interaction with TYLCV, leading to degradation of the virus. We propose that GroEL of B. tabaci protects the virus from destruction during its passage through the haemolymph.  相似文献   
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Kidney transplant (KT) outcomes for HIV-infected (HIV+) persons are excellent, yet acute rejection (AR) is common and optimal immunosuppressive regimens remain unclear. Early steroid withdrawal (ESW) is associated with AR in other populations, but its utilization and impact are unknown in HIV+ KT. Using SRTR, we identified 1225 HIV+ KT recipients between January 1, 2000, and December 31, 2017, without AR, graft failure, or mortality during KT admission, and compared those with ESW with those with steroid continuation (SC). We quantified associations between ESW and AR using multivariable logistic regression and interval-censored survival analysis, as well as with graft failure and mortality using Cox regression, adjusting for donor, recipient, and immunologic factors. ESW utilization was 20.4%, with more zero HLA mismatch (8% vs 4%), living donors (26% vs 20%), and lymphodepleting induction (64% vs 46%) compared to the SC group. ESW utilization varied widely across 129 centers, with less use at high- versus moderate-volume centers (6% vs 21%, P < .001). AR was more common with ESW by 1 year (18.4% vs 12.3%; aOR: 1.081.612.41, P = .04) and over the study period (aHR: 1.021.391.90, P = .03), without difference in death-censored graft failure (aHR 0.600.911.36, P = .33) or mortality (aHR: 0.751.151.77, P = .45). To reduce AR after HIV+ KT, tailoring of ESW utilization is reasonable.  相似文献   
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In the liver, the immunostaining of cytokeratins (CK) 7 and 20 has been used to distinguish usual peripheral cholangiocarcinomas (CC) and colorectal carcinoma metastasis (CRM). However, other subtypes of CC are not infrequent and may be particularly difficult to distinguish from CRM by histology and even immunohistochemistry. Therefore, 48 CC from different locations, either peripheral (n = 19), or nonperipheral, that is, from the large intrahepatic bile ducts, the hilum, and the extrahepatic bile ducts (n = 29), and with different cytoarchitectural patterns were tested for CK7 and CK20 and compared with 31 CRM. CC were positive for CK7 and CK20 in 96% and 70%, respectively, whatever the architecture and differentiation of the tumor. The labeling index (LI) of CK7 in CC was always high, whereas it was low or moderate for CK20. CK20-positive phenotype was significantly more frequent in nonperipheral than in peripheral CC (82% vs 47%; p = 0.007). CRM were all positive for CK20 with a high LI, and mostly negative (81%) for CK7. In conclusion, (1) the CK immunoprofile of CC varies according to the location of the tumor in the biliary tract, peripheral CC being more often CK7+/CK20-, and nonperipheral ones CK7+/CK20+; and (2) a decision tree based on CK20 LI and CK7 positivity allows the distinction of CRM and CC, even for the nonperipheral type.  相似文献   
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Between January 1993 and December 2000, an unrelated donor search (UDS) was initiated for 97 consecutive patients [46 acute lymphoblastic leukemia (ALL) and 51 acute myeloid leukemia (AML)]. Leukemia was considered to be of poor prognosis in cases of refractory disease (n=70), unfavourable karyotype (n=22) or miscellaneous (n=5). All patients had previously received various chemotherapies and 9 had undergone an autologous stem cell transplantation (SCT). The median age at UDS initiation was 25 (range 2.7-55) years. The median time to identify a suitable living donor or cord blood (CB) was 60 days. Eventually, 33 patients received unrelated allo-SCT (including 9 CB), 12 auto-SCT, 39 chemotherapy and 13 palliative treatment. At a median of 54 months, 18 patients were alive, including 15 in remission. The 4-year overall survival rates were 32%, 37%, 15% and 0% for allo-SCT, auto-SCT, chemotherapy or palliative treatment, respectively. Patients who received either allo- or auto-SCT had better survival than those who did not (P<0.0001). For ALL, only allo-SCT significantly improved survival (P<0.007). Finally, patients who received allo-SCT died less often of relapse than patients who did not (P<0.0001). Unrelated allo-SCT gives a substantial long-term survival and cure in patients with high-risk acute leukemia. For patients who achieve remission and for whom UDS fails, auto-SCT may prove to be a good approach. For patients who fail to enter into remission, intensive salvage chemotherapy has a very limited effect.  相似文献   
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Myelodysplastic syndromes (MDS) are a heterogeneous group of hemopathies that exhibit physical manifestations with clinical consequences of bone marrow failure and inherent risk of progression to acute myeloid leukemia. Iron overload (IO) is common in MDS due to chronic transfusion support and disease-related alterations in iron metabolism. IO has been conclusively associated with inferior outcomes among MDS patients. Despite lack of randomized trials showing a survival impact of iron chelation therapy (ICT), ICT is recommended by experts and guidelines for select MDS patients with IO and is often used. The availability of effective oral ICT agents has reignited the controversy regarding ICT use in patients with MDS and IO. Here we summarize the studies evaluating the value of ICT in MDS and suggest a practical approach for use of these therapies. We also highlight controversies regarding use of ICT in MDS and discuss some ongoing efforts to answer these questions.  相似文献   
10.

Background  

Neutrophil elastase level/activity is elevated in a variety of diseases such as atherosclerosis, systolic hypertension and obstructive pulmonary disease. It is unknown whether obese individuals with prehypertension also have elevated neutrophil elastase, and if so, whether it has a deleterious effect on pulmonary function. Objectives: To determine neutrophil elastase levels in obese prehypertensive women and investigate correlations with pulmonary function tests.  相似文献   
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