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排序方式: 共有7805条查询结果,搜索用时 15 毫秒
31.
Joanna Luczkowiak Gonzalo Rivas Nuria Labiod Fátima Lasala Marta Rolo Jaime Lora-Tamayo Mikel Mancheno-Losa David Rial-Crestelo Alfredo Pérez-Rivilla María Dolores Folgueira Rafael Delgado 《Journal of medical virology》2023,95(1):e28268
We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID-19 naïve and convalescent individuals. Third doses of mRNA COVID-19 vaccines induced a significant increase in potency and breadth of neutralization against SARS-CoV-2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross-neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID-19 convalescents except for BA.4/5. Avidity of RBD-binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS-CoV-2 sequences are required to induce high avidity cross-neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments. 相似文献
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HMGA1 protein overexpression in human breast carcinomas: correlation with ErbB2 expression. 总被引:6,自引:0,他引:6
Gennaro Chiappetta Gerardo Botti Mario Monaco Rosa Pasquinelli Francesca Pentimalli Maurizio Di Bonito Giuseppe D'Aiuto Monica Fedele Rodolfo Iuliano Emiliano A Palmieri Giovanna Maria Pierantoni Vincenzo Giancotti Alfredo Fusco 《Clinical cancer research》2004,10(22):7637-7644
We measured, by immunohistochemistry, HMGA1 protein expression in 212 breast tissue specimens: 6 normal samples, 28 hyperplastic lesions (13 with cellular atypia), 11 fibroadenomas, 10 in situ ductal carcinomas, 144 ductal carcinomas, and 13 lobular carcinomas. HMGA1 was not expressed in normal breast tissue; HMGA1 staining was intense in 40% of hyperplastic lesions with cellular atypia and in 60% of ductal carcinomas and weak in fibroadenomas and in hyperplastic lesions without cellular atypia. Because HMGA1 expression was similar among ductal breast carcinomas with different histologic grading, we evaluated the association between HMGA1 expression and that of other markers of breast carcinoma invasion (estrogen and progesterone receptors, Ki-67 antigen, and ErbB2) in 21 cases of grade 3 breast ductal carcinomas and 7 cases of breast lobular carcinomas. We found that HMGA1 expression tended to be associated only with c-erbB-2 expression (Spearman rho: 0.36; P=0.065). Taken together, these results suggest that HMGA1 expression might be a novel indicator for the diagnosis and prognosis of human breast cancer. 相似文献
35.
Mark X. Ransom Alfredo J. Garcia Kerry Doherty Robert Shelden Ekkehard Kemmann 《Journal of assisted reproduction and genetics》1997,14(1):35-38
Purpose: Our aim was to examine the potential of the uterine cavity to affect fertilization and early embryo development.
Design: A prospective IRB-approved protocol for patients fulfilling study eligibility criteria was used.
Methods: Patients studied included those with primary or secondary infertility, aged less than 38 years, with no history of severe
male-factor infertility, and with hysterosalpingogram-and laparoscopic-confirmed bilateral proximal tubal occlusion. Superovulation
induction was accomplished with a combination of GnRH agonist and menotropins, with serum hormonal and sonographic monitoring.
Within 24 hr prior to, and again at the time of, ovulatory hCG administration, progesterone (P4) was given. Sonographic-guided
transvaginal retrieval was performed 35 hr after hCG. Between four and six oocytes were returned to the uterine cavity, admixed
with sperm, immediately following retrieval. Luteal support consisted of daily P4 administration.
Results: Of the 20 patients recruited for the study, all completed the retrieval and transfer procedure. A total of four clinical
pregnancies was achieved, with one early first-trimester loss, one late first-trimester loss (Trisomy 14), and two healthy
term infants delivered. IVF of surplus oocytes demonstrated a 82.5% fertilization rate and 66.7% cleavage following cryopreservation.
Conclusions: Human fertilization can be achieved through direct uterine transfer of gametes. Furthermore, administration of P4 prior to
the ovulatory dose of hCG is compatible with in vitro or in vivo fertilization and implantation. 相似文献
36.
Luisa Di Marzio Alfredo Di Leo Benedetta Cinque Donatella Fanini Alessio Agnifili Pasquale Berloco Michele Linsalata Dionigi Lorusso Michele Barone Claudio De Simone Maria Grazia Cifone 《Cancer epidemiology, biomarkers & prevention》2005,14(4):856-862
OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms. 相似文献
37.
Javier Sastre Eugenio Marcuello Bartomeu Masutti Matilde Navarro Silvia Gil Antonio Antón Albert Abad Enrique Aranda Joan Maurel Manuel Valladares Inmaculada Maestu Alfredo Carrato José María Vicent Eduardo Díaz-Rubio 《Journal of clinical oncology》2005,23(15):3545-3551
PURPOSE: Elderly patients constitute a subpopulation with special characteristics that differ from those of the nonelderly and have been underrepresented in clinical trials. This study was performed to determine the efficacy and safety of irinotecan (CPT-11) in combination with fluorouracil (FU) administered as a 48-hour continuous infusion twice a month in elderly patients. PATIENTS AND METHODS: Patients > or = 72 years old with metastatic colorectal cancer, Eastern Cooperative Oncology Group performance status of 0 to 1, no geriatric syndromes, and no prior treatment were treated every 2 weeks with CPT-11 180 mg/m2 plus FU 3,000 mg/m2 in a 48-hour continuous infusion. RESULTS: By intent-to-treat analysis, in 85 assessable patients, the objective response rate was 35% (95% CI, 25% to 46%), and stable disease was 33% (95% CI, 23% to 44%). Median time to progression was 8.0 months (95% CI, 6.0 to 10.0 months), and median overall survival time was 15.3 months (95% CI, 13.8 to 16.9 months). Toxicity was moderate. Grade 3 and 4 neutropenia, diarrhea, and asthenia were observed in 21%, 17%, and 13% of patients, respectively. Only one case of neutropenic fever occurred. There were two toxic deaths, one was a result of grade 4 diarrhea and acute kidney failure, and the other was a result of massive intestinal hemorrhage in the first cycle. The study of prognostic factors did not reveal any predictive factor of response. Response to treatment and baseline lactate dehydrogenase were the main factors conditioning progression-free and overall survival. CONCLUSION: Twice a month continuous-infusion CPT-11 combined with FU is a valid therapeutic alternative for elderly patients in good general condition. 相似文献
38.
FGFR3 and Tp53 mutations in T1G3 transitional bladder carcinomas: independent distribution and lack of association with prognosis. 总被引:3,自引:0,他引:3
Silvia Hernández Elena López-Knowles Josep Lloreta Manolis Kogevinas Roberto Jaramillo Alex Amorós Adonina Tardón Reina García-Closas Consol Serra Alfredo Carrato Núria Malats Francisco X Real 《Clinical cancer research》2005,11(15):5444-5450
FGFR3 and Tp53 mutations have been proposed as defining two alternative pathways in the pathogenesis of transitional bladder cancer. FGFR3 mutations are associated with low-grade tumors and a favorable prognosis. Tp53 alterations are associated with advanced tumors and, possibly, with a poor prognosis. We focus here on the subgroup of T1G3 superficial tumors because they are a major clinical challenge. Patients (n = 119) were identified from a prospective study of 1,356 cases. Mutations in FGFR3 (exons 7, 10, and 15) and Tp53 (exons 4-9) were analyzed using PCR and direct sequencing. All cases were followed for recurrence and death. Survival was analyzed using Kaplan-Meier curves and multivariable Cox regression. FGFR3 mutations were detected in 20 (16.8%) tumors; 100 mutations in Tp53 were found in tumors from 78 (65.5%) cases. Multiple alterations in Tp53 were present in 19 tumors (16%). Inactivating mutations were present in 58% of tumors. The combined mutation distribution (FGFR3/Tp53) was: wt/wt (34.5%), mut/wt (7.6%), wt/mut (48.7%), and mut/mut (9.2%), indicating that the presence of either mutation did not depend on the other (P value = 0.767). FGFR3 and Tp53 mutations were not associated with clinicopathologic characteristics of patients and did not predict, alone or in combination, recurrence or survival. Taking the risk of the wt/wt group as reference, the mutation-associated risks of cancer-specific mortality were: mut/wt 1.42 (0.15-13.75), wt/mut 0.67 (0.19-2.31), mut/mut 1.62 (0.27-9.59). These molecular features support the notion that T1G3 tumors are at the crossroads of the two main molecular pathways proposed for bladder cancer development and progression. 相似文献
39.
Sonia Maciá Escalante Carmen Guillén Ponce Ma José Molina Garrido Ma José Martínez Ortiz Inmaculada Ballester Navarro Alfredo Carrato Mena 《Clinical & translational oncology》2005,7(9):414-416
Prognosis in prostate cancer is determined, in greater part, by the presence of metastases. Bone metastases can occur in any part of the skeleton even, for example, at the base of the skull. We present a case of a 78 year old male who, in December 2001, presented with paralysis of the third cranial nerve. The NMR and CAT scans were normal and circulating levels of PSA were elevated. He was referred to the Urology Service where the treatment guidelines included complete androgen block. Subsequently, he developed retro-orbital pain, divergent strabismus and palpebral ptosis. CAT and NMR indicated a soft tissue mass at the sphenoid level. Treatment was Gamma Knife Radio-surgery. Since August 2004, in conjunction with the latest rise in PSA, the patient's general status deteriorated considerably and he was referred to the Oncology Service. there was an increase in the paralysis of the third, fourth and sixth cranial nerve (complete left ophthalmoplegia) and left-central facial paralysis. Metastases from prostate cancer can be disseminated via the lymphatic or the blood system. Currently, there are more metastases from large-size tumours. Metastases are critical in prostate cancer because of their adverse effect on the patient's survival. Measurements of circulating levels of prostate specific antigen and prostate acid phosphatase are very useful in the clinical diagnosis of the primary tumour, or its metastases. 相似文献
40.