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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Sin‐wan Cheung Pauline Cho Ben Chan Camus Choy Vincent Ng 《Clinical & experimental optometry》2007,90(2):124-131
Background: Our aim was to compare the clinical performance of a biweekly (second generation) silicone hydrogel lens and a biweekly hydrogel lens worn for daily wear modality. Methods: We used a double‐masked study, in which non‐presbyopic, asymptomatic and adapted soft lens wearers were recruited. Subjects wore a silicone hydrogel lens in one eye and a hydrogel lens in the other (lens types and eyes were randomly assigned) for one month. Lenses were replaced every two weeks. Contact lens fitting, pre‐lens tear film thinning time, vision, corneal integrity and lens deposits were assessed before and every fortnight after delivery of new lenses. A questionnaire was used to compare the subjective performance of the two lens types. Results: Thirty of the 33 subjects completed the study. There were no significant differences in lens fitting (centration and movement), pre‐lens tear film thinning time, vision or corneal integrity between the two lens types. Statistically, there was no significant difference in lens deposits between the two lens types but silicone hydrogel lenses tended to have more Grade 3 to 4 lipid deposits than hydrogel lenses. Subjects found no significant differences between the two lens types in terms of vision and comfort. Preference for silicone hydrogel lenses increased from 33 at the first after‐care visit to 50 per cent at the second after‐care visit. Conclusion: This short‐term study demonstrates that the performance of silicone hydrogel and hydrogel lenses is comparable but the former tends to build up more lipid deposits than the latter. We did not find better performance in terms of ocular integrity of silicone hydrogel lenses compared to the hydrogel lenses, probably because the subjects were adapted asymptomatic contact lens wearers before commencing the study. Contact lens wearers having hypoxia‐related problems are likely to benefit from using silicone hydrogel lenses, as these lenses provide at least three times more oxygen than conventional hydrogel lenses. 相似文献
972.
AIM: To report detection of leprosy in ocular tissue by histopathology and its confirmation by genetic analysis. METHODS: Excised tissue from a clinically-suspected ocular leprosy patient was processed and analyzed histopathologically. The DNA from the paraffin-embedded tissue was extracted, an 85 A-C intergenic region of Mycobacterium leprae was amplified using specific primers and analyzed by conventional as well as real-time polymerase chain reaction (RT-PCR). RESULTS: With periodic acid-Schiff-hematoxylin (PAS-H) staining the specimen showed presence of a thin fibrinous layer of inflammatory cells. The majority of the tissue was fibrovascular with extensive infiltration by histiocytes having reticulated cytoplasm. Modified PAS-H and acid-fast staining (AFS) showed the presence of several acid-fast organisms within the cytoplasm of histiocytes and mast cells. Conventional PCR showed a 250-bp DNA from excised conjunctival tissue, which was in agreement with the positive controls for M. leprae. Through RT-PCR, it was calculated that the suspected tissue had 44.68 pg of M. leprae DNA, which is 8937.06 genome copies of M. leprae. CONCLUSIONS: Presence of inflammatory cells and AFS bacilli in tissue presented a typical picture of leprosy. M. leprae DNA can be detected using RT-PCR in ocular tissues when acid-fast bacteria are seen in histopathological sections. And when the diagnosis of leprosy is inconclusive and acid-fast bacteria are seen, RT-PCR for M. leprae DNA could be used as a rapid confirmatory test to identify the presence of M. leprae and, therefore, the diagnosis of leprosy. 相似文献
973.
Immunophenotyping of cutaneous lymphoid infiltrates in frozen and paraffin-embedded tissue sections: a comparative study 总被引:1,自引:0,他引:1
L Cerroni J Smolle H P Soyer A Martinez Aparicio H Kerl 《Journal of the American Academy of Dermatology》1990,22(3):405-413
A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections was compared with a panel of antibodies reactive in frozen sections for the immunophenotyping of cutaneous lymphoproliferative disorders. Three T cell-associated markers (UCHL1, MT-1, MT-2, six B cell-associated markers (MB-1, MB-2, LN-1, LN-2, L-26, 4KB5), immunoglobulin heavy and light chains, anti-LCA antibody, two markers for Reed-Sternberg cells (Ber-H2, Leu-M1), one marker for macrophages (Mac-387) and anti-S-100 protein antibody were tested on normal skin, inflammatory skin diseases, and cutaneous lymphomas and pseudolymphomas. On the basis of the results in frozen sections, 12 inflammatory T cell diseases, 14 T cell lymphomas and pseudolymphomas, and 10 B cell lymphomas and pseudolymphomas were identified. In addition, two cases of specific skin infiltrates of Hodgkin's disease have been examined. Among T cell markers, the greatest sensitivity was exhibited by UCHL1, which stained all but one specimen of T cell infiltrate; it was negative in one specimen of mycosis fungoides that progressed into a T-immunoblastic lymphoma. The combined use of MB-2, LN-2, and 4KB5 identified all B cell proliferations. LN-1 marked germinal centers in all cases of follicular lymphoma and pseudolymphoma. Ber-H2 stained the Reed-Sternberg cells in both cases of Hodgkin's disease and the large cells in the histiocytic type of lymphomatoid papulosis. Mac-387 and anti-S-100 protein antibody recognized macrophages and T-zone histiocytes (Langerhans cells and interdigitating cells), respectively. A panel of antibodies reactive in routinely fixed, paraffin-embedded tissue sections is proposed that facilitates the identification of most B and T cell infiltrates in the skin. 相似文献
974.
S Urrutia M A Piris J L Orradre B Martinez M A Cruz D Garcia-Almagro 《The American Journal of dermatopathology》1990,12(6):603-606
A case of cutaneous cytotoxic/suppressor T-cell (CD8+, CD4-) lymphoma is reported. The tumor was characterized by its rapid growth and no response to polychemotherapy. This unusual immunophenotype seems to be associated, in this and other cases reported previously, with a more aggressive course than the classic indolent course of cutaneous T-cell lymphoma. 相似文献
975.
976.
Dae Won Kim Elaine Tan Jun-Min Zhou Michael J. Schell Maria Martinez James Yu Estrella Carballido Rutika Mehta Jonathan Strosberg Iman Imanirad Richard D. Kim 《British journal of cancer》2021,124(11):1803
Background MMR proficient (pMMR) colorectal cancer (CRC) is usually unresponsive to immunotherapy. Recent data suggest that ibrutinib may enhance the anti-tumour activity of anti-PD-1 immunotherapy. In this study, we evaluated the safety and efficacy of ibrutinib plus pembrolizumab in refractory metastatic CRC.Methods This was a phase 1/2 study in patients with refractory metastatic pMMR CRC. The primary endpoints for phases 1 and 2 were maximum tolerated dose (MTD) and disease control rate, respectively. The secondary endpoints were safety, progression-free survival (PFS) and overall survival (OS).Results A total of 40 patients were enrolled. No dose-limiting toxicity was observed, and MTD was not identified. The highest tested dose of ibrutinib, 560 mg once daily, was combined with a fixed dose of pembrolizumab 200 mg every 3 weeks for the phase 2 portion. The most common grade 3/4 treatment-related adverse events were anaemia (21%), fatigue (8%) and elevated alkaline phosphatase (8%). Among 31 evaluable patients, 8 (26%) achieved stable disease, and no objective response was observed. The median PFS and OS were 1.4 and 6.6 months, respectively.Conclusion Ibrutinib 560 mg daily plus pembrolizumab 200 mg every 3 weeks appears to be well tolerated with limited anti-cancer activity in metastatic CRC.ClinicalTrials.gov identifier .Subject terms: NCT03332498Cancer immunotherapy, Colorectal cancer 相似文献
977.
Julie C. Sapp Anna Buser Jasmine Burton‐Akright Kim M. Keppler‐Noreuil Leslie G. Biesecker 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(4):565-570
Phenotype‐based diagnostic criteria were developed for Proteus syndrome in 1999 and updated in 2006. Subsequently, the causative mosaic gene alteration was discovered, the c.49G>A p.E17K variant in AKT1. As well, a number of overlapping overgrowth disorders attributable to mosaic PIK3CA variants have now been characterized, leading to the designation of PIK3CA‐related overgrowth spectrum (PROS). Finally, ongoing work to better characterize Proteus syndrome has led to identification of additional features of that disorder that could be useful in diagnostic criteria. We have taken the opportunity of these discoveries to re‐evaluate the Proteus syndrome diagnostic criteria. Here we propose a new set of diagnostic criteria that establishes a weighted, point‐based system for the phenotypic attributes and then integrates that with the potential molecular test results to result in one of two designations: AKT1‐related Proteus syndrome or AKT1‐related overgrowth spectrum. A patient whose only manifestation is an AKT1 c.49G>A‐positive tumor would receive neither of these designations. Here we review the rational basis of diagnostic criteria and argue that a unitary diagnostic entity is a distinct gene‐phenotype dyad and that this should be the model for all mendelian disorders. The gene‐alone or phenotype‐alone approach is inadequate to rigorously delineate a unitary diagnostic entity. 相似文献
978.
979.
Travis WD Hunninghake G King TE Lynch DA Colby TV Galvin JR Brown KK Chung MP Cordier JF du Bois RM Flaherty KR Franks TJ Hansell DM Hartman TE Kazerooni EA Kim DS Kitaichi M Koyama T Martinez FJ Nagai S Midthun DE Müller NL Nicholson AG Raghu G Selman M Wells A 《American journal of respiratory and critical care medicine》2008,177(12):1338-1347
980.
Nahum Méndez‐Sánchez Daniel Zamora‐Valdés José A. Flores‐Rangel Julio A. Pérez‐Sosa Francisco Vásquez‐Fernández Jezer I. Lezama‐Mora Genaro Vázquez‐Elizondo Guadalupe Ponciano‐Rodríguez Martha H. Ramos Misael Uribe 《Liver international》2008,28(3):402-406
Background/Aims: Gallstone disease (GD) and cardiovascular disease (CD) are common diseases worldwide with considerable economical impact and they are strongly associated. Carotid atherosclerosis is an excellent marker of risk for CD like stroke and myocardial infarction. The aim of this study was to assess the association between gallstones and carotid atherosclerosis. Methods: A cross‐sectional study was conducted. We evaluated subjects with ultrasonographical evidence of GD and asymptomatic subjects without such evidence. Anthropometric, clinical and biochemical variables were collected. The Metabolic syndrome was evaluated using adult treatment panel III criteria. Carotid artery intima–media thickness (CIMT) was determined by a standard ultrasound protocol. Insulin‐like growth factor‐1 (IGF‐1) serum levels were measured in all subjects. Results: We studied 191 subjects: 62 subjects with GD (53.2% males) and 129 asymptomatic subjects without GD (65.9% males). Subjects with GD exhibited a higher body mass index, body fat percent, insulin serum levels and CIMT (P<0.05 for all). The prevalence of GD was higher in subjects with a CIMT>0.75 independently of other factors [odds ratio (OR) 2.12, 95% confidence interval (CI) 1.04–4.34; P=0.039], and for every 0.1 mm increase in CIMT the independent probability to be a case of GD increased by a factor of 1.25 (95% CI 1.02–1.53; P=0.027). IGF‐1 levels did not differ among groups. Conclusions: Subjects with GD exhibit greater carotid atherosclerosis, and therefore have a higher risk for stroke and myocardial infarction. 相似文献