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1.
Disseminated histoplasmosis is one the main AIDS-defining opportunistic infections in HIV-infected patients, notably in Latin America. The non-specific and proteiform clinical presentation leads to diagnostic delays that may lead to fatal outcomes. This retrospective multicentric study aimed to describe the frequency and manifestations of gastrointestinal histoplasmosis in French Guiana, and to compare patients with disseminated histoplasmosis with or without gastrointestinal involvement.Between January 1, 1981 and October 1, 2014 co-infections with HIV and histoplasmosis were enrolled. Inclusion criteria were: age >18 years, confirmed HIV infection; first proven episode of histoplasmosis.Among 349 cases of disseminated histoplasmosis, 245 (70%) had a gastrointestinal presentation. Half of patients with gastrointestinal signs had abdominal pain or diarrhea, mostly watery. Half of patients with abdominal pain had diarrhea (63/124) and half of those with diarrhea (63/123) had abdominal pain. A significant proportion of patients also had hepatomegaly and, to a lesser degree, splenomegaly. After adjusting for potential confounding, the presence of lymphadenopathies >2cm (AOR = 0.2, IC95 = 0.04–0.7, P = 0.01), Haitian origin (AOR = 0.04, IC95 = 0.004–0.4, P = 0.006) were associated with a lower prevalence of gastrointestinal signs and positive gastrointestinal presence of H. capsulatum. Persons with a gastrointestinal H. capsulatum were more likely to have a decreased prothrombin time, lower ferritin, lower liver enzymes, and lower concentrations of LDH than those without gastrointestinal signs and symptoms. They also had a shorter interval between symptoms onset and diagnosis. Patients with a positive gastrointestinal identification of H. capsulatum were less likely to die at 1 month than those without a gastrointestinal presentation (respectively, 4.6% vs 18.5%, P = 0.01).Subacute or chronic gastrointestinal presentations are very frequent during disseminated histoplasmosis, they seem less severe, and should lead to suspect the diagnosis in endemic areas. There were populational or geographic differences in the frequency of gastrointestinal manifestations that could not be explained.  相似文献   
2.

Background

Hepatitis E virus (HEV) infection takes a clinically silent, self-limited course in the far majority of cases. Chronic hepatitis E has been reported in some cohorts of immunocompromised individuals. The role of HEV infections in patients with autoimmune hepatitis (AIH) is unknown.

Methods

969 individuals were tested for anti-HEV antibodies (MP-diagnostics) including 208 patients with AIH, 537 healthy controls, 114 patients with another autoimmune disease, rheumatoid arthritis (RA), and 109 patients with chronic HCV- or HBV-infection (HBV/HCV). Patients with AIH, RA and HBV/HCV were tested for HEV RNA. HEV-specific proliferative T cell responses were investigated using CFSE staining and in vitro stimulation of PBMC with overlapping HEV peptides.

Results

HEV-antibodies tested more frequently positive in patients with AIH (n = 16; 7.7%) than in healthy controls (n = 11; 2.0%; p = 0.0002), patients with RA (n = 4; 3.5%; p = 0.13) or patients with HBV/HCV infection (n = 2; 2.8%; p = 0.03). HEV-specific T cell responses could be detected in all anti-HEV-positive AIH patients. One AIH patient receiving immunosuppression with cyclosporin and prednisolone and elevated ALT levels had acute hepatitis E but HEV viremia resolved after reducing immunosuppressive medication. None of the RA or HBV/HCV patients tested HEV RNA positive.

Conclusions

Patients with autoimmune hepatitis but not RA or HBV/HCV patients are more likely to test anti-HEV positive. HEV infection should been ruled out before the diagnosis of AIH is made. Testing for HEV RNA is also recommended in AIH patients not responding to immunosuppressive therapy.  相似文献   
3.
4.
Determination of the extent of DNA bending by an adenine-thymine tract   总被引:26,自引:0,他引:26  
H S Koo  J Drak  J A Rice  D M Crothers 《Biochemistry》1990,29(17):4227-4234
We determined the magnitude of the bend induced in DNA by an adenine-thymine tract by measuring the rate of cyclization of DNA oligonucleotides containing phased A tracts. A series of linear multimers with 2-bp single-stranded ends, in which the (A.T)6 tracts are separated by CG2-3C sequences and are positioned 10 and 11 bp apart alternately, were prepared from 21 bp long synthetic duplexed deoxyoligonucleotides. The cyclization rates of the multimers (105-210 bp) and the bimolecular association rate of the 84 bp long multimer were measured in the presence of DNA ligase. From the rate constants of the cyclization and bimolecular association reactions, ring closure probabilities were obtained for the multimers. The systematically bent molecules were simulated by Monte Carlo methods, and the ring closure probabilities were calculated for a given set of junction bend angles. By comparing the calculated values of ring closure probabilities to experimental values and adjusting the junction bend angles to fit experimental values, the extent of bending at the junctions (or the extent of bending for an adenine tract) was determined. We conclude that an A6 tract bends the DNA helix by 17-21 degrees.  相似文献   
5.
Objectives:  To report the cytological aspects of ano-rectal basaloid carcinoma (BC) variant in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) conventional and liquid-based cytology (LBC), in a series of 10 cases of deep-seated squamous cell carcinomas (SCC), and to discuss the diagnostic difficulties in interpreting the morphology and immunocytochemical findings.
Methods:  Ten cases of EUS-FNA smears and LBC specimens of deep-seated pelvic masses were retrospectively collected from January 2001 to November 2006.
Results:  Ten EUS-FNA specimen cases were SCC, eight corresponding to usual SCC and two to BC-variant. Of these two cases, only one was correctly diagnosed by EUS-FNA specimen, whereas in the second case, the initial cytological diagnosis was poorly differentiated adenocarcinoma and the final diagnosis of basaloid carcinoma variant was established on surgical resection. Immunocytochemistry (ICC) using CK7, CK20 and CK34βe12 on FNA specimens confirmed the diagnosis retrospectively.
Conclusion:  The diagnosis of basaloid variant of SCC in a rectal location can be very difficult, both on account of the uncommon location and because of the low specificity of morphological aspects on EUS-FNA smears. The immunocytochemical technique, including a limited spectrum of keratins (CK7, CK20, CK34βe12, and p63) is necessary to avoid this diagnostic pitfall.  相似文献   
6.
BackgroundRadiofrequency ablation at the region of the sinus of Valsalva carries a risk to the ostia of the coronary arteries. Coronary angiography is usually utilized to document a safe distance for mapping and ablation.ObjectiveTo show that catheter ablation in the aortic root could be guided by phased-array intra cardiac echocardiography (ICE) and electro anatomic mapping without the need for coronary angiography.MethodsWe reviewed all patients referred to our lab that underwent mapping and/or ablation in the sinus of Valsalva region. Procedures were carried out by operators that are skilled in the use of ICE. The need for angiography was documented, also the rate of success along with the immediate and 30-day complications rate.ResultsSeventy patients (average age 48.7 ± 13.8 years; 64.3% males) were referred for ablation of ventricular and atrial arrhythmias. PVC constituted 95.7% of the cases. All patients underwent mapping and/or ablation at the sinus of Valsalva region without the need for coronary angiography to visualize the coronary ostia. Acute and effective ablation was achieved in 57 out of 70 (81.4%) patients partially effective ablation was achieved in 10 (14.3%) patients, and failure to ablate in the remaining 3 patients (4.3%). There was no occurrence of any adverse events, neither immediately or at day 30 after the procedure.ConclusionIn the hands of experienced operators, mapping and radiofrequency ablation in the sinus of Valsalva can be safely and reliably performed using intracardiac echocardiography alone without the need for supplementary catheter coronary angiography.  相似文献   
7.
T S Baker  J Drak    M Bina 《Biophysical journal》1989,55(2):243-253
The three-dimensional structure of the simian virus 40 capsid is remarkably similar to the structure of the polyoma empty capsid. This similarity is apparent despite striking differences in the methods used to determine the two structures: image analysis of electron micrographs of frozen-hydrated samples (SV40 virions) and an unconventional x-ray crystallographic analysis (polyoma empty capsids). Both methods have clearly resolved the 72 prominent capsomere units which comprise the T = 7d icosahedral capsid surface lattice. The 12 pentavalent and 60 hexavalent capsomeres consist of pentameric substructures. A pentameric morphology for hexavalent capsomeres clearly shows that the conserved bonding specificity expected from the quasi-equivalence theory is not present in either SV40 or polyoma capsids. Determination of the SV40 structure from cryo-electron microscopy supports the correctness of the polyoma structure solved crystallographically and establishes a strong complementarity of the two techniques. Similarity between the SV40 virion and the empty polyoma capsid indicates that the capsid is not detectably altered by the loss of the nucleohistone core. The unexpected pentameric substructure of the hexavalent capsomeres and the arrangement of the 72 pentamers in the SV40 and polyoma capsid lattices may be characteristic features of all members of the papova virus family, including the papilloma viruses such as human wart and rabbit papilloma.  相似文献   
8.
9.

Background

Clinicians use clinical and pathological parameters, such as tumour size, grade and nodal status, to make decisions on adjuvant treatments for breast cancer. However, therapeutic decisions based on these features tend to vary due to their subjectivity. Computational and mathematical algorithms were developed using clinical outcome data from breast cancer registries, such as Adjuvant! Online and NHS PREDICT. More recently, assessments of molecular profiles have been applied in the development of better prognostic tools.

Methods

Based on the available literature on online registry-based tools and genomic assays, we evaluated whether these online tools could be valid and accurate alternatives to genomic and molecular profiling of the individual breast tumour in aiding therapeutic decisions, particularly in patients with early ER-positive breast cancer.

Results and conclusions

Early breast cancer is currently considered a systemic disease and a complex ecosystem with behaviour determined by the complex genetic and molecular signatures of the tumour cells, mammary stem cells, microenvironment and host immune system. We anticipate that molecular profiling will continue to evolve, expanding beyond the primary tumour to include the tumour microenvironment, cancer stem cells and host immune system. This should further refine therapeutic decisions and optimise clinical outcome.This article was specially invited by the editors and represents work by leading researchers.
  相似文献   
10.
Immunotherapy is an attractive approach for treating cancer. T‐cell engagers (TCEs) are a type of immunotherapy that are highly efficacious; however, they are challenged by weak T‐cell activation and short persistence. Therefore, alternative solutions to induce greater activation and persistence of T cells during TCE immunotherapy is needed. Methods to activate T cells include the use of lectins, such as phytohemagglutinin (PHA). PHA has not been used to activate T cells in vivo, for immunotherapy, due to its biological instability and toxicity. An approach to overcome the limitations of PHA while also preserving its function is needed. In this study, we report a liposomal PHA which increased PHA stability, reduced toxicity and performed as an immunotherapeutic that is able to activate T cells for the use in future cancer immunotherapies to circumvent current obstacles in immunosuppression and T‐cell exhaustion.  相似文献   
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