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排序方式: 共有578条查询结果,搜索用时 11 毫秒
1.
Dibasic staining of large epoxy tissue sections and applications to surgical pathology 总被引:3,自引:0,他引:3
A variety of normal and pathologic aldehyde-fixed osmium postfixed human tissues were prepared as large sections embedded in Spurr epoxy. They were stained with a sequential basic fuchsin--methylene blue stain which gives "hematoxylin- and eosin-like" staining and additionally functions as several special stains. This technic also allows for electron microscopy directly on the embedded tissue. The histologic and cytologic preservation and overall staining was superior to tissue embedded in glycol methacrylate. The methods and technics presented in this article have important applications in diagnostic surgical pathology and histology in general. 相似文献
2.
Reducing the time of sperm-oocyte interaction in human in-vitro fertilization improves the implantation rate 总被引:4,自引:1,他引:4
Gianaroli Luca; Magli M.Cristina; Ferraretti Anna Pia; Fiorentino Agnese; Tosti Elisabetta; Panzella Sergio; Dale Brian 《Human reproduction (Oxford, England)》1996,11(1):166-171
Human oocyte development was evaluated after a reduced timeexposure to spermatozoa in vitro. A total of 119 patients wereassigned to two study groups in a randomized prospective studyin which each patients oocytes were exposed to spermatozoafor either 1 h (group 1 58 patients) or the standard16 h incubation period (group 2 61 patients). The fertilizationrate obtained in group 1 was higher than in group 2 (285/393,73%, and 272/410, 66% respectively), suggesting that the spermatozoa-oocyteinteraction occurs within 1 h. This was confirmed in a studyin vitro using fluorescently labelled spermatozoa and normaloocyte-cumulus complexes. Spermatozoa enter the cumulus complexwithin 15 min, traverse the cumulus layer within 3 h, and firstappear in the oocyte cortex at 4 h post-insemination. The incidenceof polyspermy was higher in oocytes exposed to spermatozoa for16 h (3%) than for 1 h (1%). There was no difference in thecleavage rate or morphological characteristics of embryos fromboth study groups. However, when evaluating the timing of embryodevelopment, group 1 generated a significantly higher percentageof four to five cell embryos when compared to group 2 (55 versus39%; P < 0.001), documented at 40 h post-insemination. Theimplantation and pregnancy rates for group 1 were 11 and 28%,while the corresponding rates for group 2 were 8 and 15%. Thissuggests that a reduced exposure of oocyte to spermatozoa favoursembryo viability, possibly due to a decrease in potential damagefrom sperm metabolic waste products. 相似文献
3.
Donato Gemmati Alessia Ongaro Gian L Scapoli Matteo Della Porta Silvia Tognazzo Maria L Serino Eros Di Bona Francesco Rodeghiero Giuseppe Gilli Roberto Reverberi Angelo Caruso Michela Pasello Agnese Pellati Monica De Mattei 《Cancer epidemiology, biomarkers & prevention》2004,13(5):787-794
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation. 相似文献
4.
Agnese Olivera-Toro Rubén Fossion Lei Li Rosa E. López-Gómez Emma López-Espinosa Ismael Jiménez-Estrada Salvador Quiroz-González 《Journal of acupuncture and meridian studies》2019,12(4):111-121
Many functional diseases are related to dysautonomia, and heart rate variability has been used to assess dysautonomia. However, heart rate variability has not been studied in Spleen-Qi deficiency syndrome (SQDS). Healthy volunteers (n = 37) and patients with SQDS (n = 67), recruited from the Clinic of the State University of Ecatepec Valley were included in the study. Outcome measures were average heart rate, standard deviation of the normal-to-normal heartbeat intervals, low frequency (LF), high frequency (HF) power, and the LF/HF ratio. Also, intestinal peristalsis, gastrointestinal symptoms (GSs), fatigue, and level of attention were measured. Standard deviation of the normal-to-normal heartbeat intervals (17 ± 2.3%) and HF (14 ± 3.1%) were lower in SQDS patients (17 ± 1.3%) than in healthy volunteers. SQDS patients had higher heart rate, LF power, LF/HF ratio, and fatigue scores (9.6 ± 1.12%, 16 ± 2.1%, 22 ± 3.8%, and 21 ± 4.1%). The fatigue correlated positively with the LF/HF ratio and negatively with HF power. The SQDS group had lower concentration performance (16.2 ± 1.9%) in the d2 test. The intestinal peristalsis showed a reduction (15 ± 1.3%) as compared with control. GS score and peristalsis correlated negatively with HF. Our results suggest that the pathology of SDQS could be associated with a low vagal tone which causes a decrease in peristalsis, increased fatigue, reduced attention, and appearance of GSs. 相似文献
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6.
Ulianich L Secondo A De Micheli S Treglia S Pacifico F Liguoro D Moscato F Marsigliante S Annunziato L Formisano S Consiglio E Di Jeso B 《European journal of endocrinology / European Federation of Endocrine Societies》2004,150(6):851-861
OBJECTIVE: We recently reported that the sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) 2b is the SERCA form preferentially expressed in rat thyroid. Moreover, SERCA2b expression dramatically decreases in virally transformed, highly tumorigenic, PC Cl3 thyroid cells. These results suggest that, in the thyroid, SERCA2b, in addition to its housekeeping role, is linked to differentiation and is a regulated gene. We therefore sought to study the effect of TSH, the main regulator of thyroid function, on SERCA2b expression and activity. METHODS: PC Cl3 cells were hormone starved in low-serum medium and stimulated for long (48 h) or short (1, 2 and 4 h) times. SERCA2b expression and activity were evaluated by Northern and Western blots, Ca2+-ATPase activity and Ca2+ store content. RESULTS: In PC Cl3 cells, SERCA2b mRNA and protein were induced twofold by a 48-h long treatment with TSH. Long-term elevation (48 h) of intracellular cAMP levels, by forskolin or 8-Br-cAMP, had similar effects on SERCA2b mRNA and protein. We also measured Ca2+-ATPase activity and Ca2+ store content. Both long (48 h) and short (0.5-1 h) treatments with TSH, forskolin or 8-Br-cAMP induced a marked increase of SERCA2b activity. This effect was completely abolished by H89, a specific inhibitor of cAMP-dependent protein kinase A (PKA). TSH and 8-Br-cAMP increased Ca2+ store content after both long (48 h) and short (1-2 h) treatments. CONCLUSIONS: These data suggested that TSH/cAMP acts as an important regulator of both SERCA2b expression and activity in the thyroid system, through PKA activation. 相似文献
7.
Clara Ugolini Fulvio Basolo Agnese Proietti Paolo Vitti Rossella Elisei Paolo Miccoli Antonio Toniolo 《Thyroid》2007,17(5):389-393
OBJECTIVE: Numerous studies indicate that papillary thyroid carcinomas (PTC) with lymphocytic infiltrates are associated with a less extensive disease at diagnosis and improved disease-free survival. The infiltration of lymphocytes and immature CD1a+ dendritic cells (DC) was characterized in papillary, poorly differentiated (PDC), and undifferentiated (UC) carcinomas to evaluate their association with immunological infiltrates. DESIGN: A series of 527 consecutive cases of thyroid carcinoma treated by total thyroidectomy were investigated by histopathological and immunohistochemical methods. The inflammatory infiltrate was quantified and typed in intratumoral and peritumoral tissues as well as in the controlateral lobe. MAIN OUTCOME: The intratumoral infiltrate was strongly reduced or absent in PDC and UC. Intense infiltrates were detected in the PTC tall cell variant. In all histotypes, the extent of the intratumoral and peritumoral infiltrates was comparable. Immature DC were detected in PTCs and markedly reduced in PDC and UC. CD1a+ DCs were detected in a small percentage of PDC and UC. CONCLUSIONS: Though a relationship between the extent of lymphocyte/DC infiltrates and the prognosis of PTCs could not be demonstrated, tumors with poor prognosis (PDCs, UCs) were characterized by markedly reduced lymphocyte/DC infiltrates. The study appears to confirm the protective role of DC and infiltrating lymphocytes against thyroid tumors. 相似文献
8.
Stefania Vedovato Angela Lo Iacono Carla Morando Agnese Suppiej Eva Orzan Daniele Trevisanuto 《The journal of maternal-fetal & neonatal medicine》2015,28(8):895-899
Objective: Histological chorioamnionitis (HCAM) has been associated with inflammatory diseases of preterm infants. Recently we have observed that it increased the risk of speech delay and hearing loss. So the aim of this study was to evaluate the relationship between sensorineural hearing loss (SNHL) of VLBW infants and HCAM.Methods: We performed an observational study on VLBW infants admitted to the NICU of Padua. Each patient with HCAM was matched with one control without HCAM. All infants underwent hearing screening before discharge by means of automated transient–evoked otoacustic emissions and automated auditory brainstem responses, which were repeated at 3 and 6 months of age with tympanometry measurement. Incidence of SNHL at 6 months of age was compared in the 2 groups and risk factors for hearing loss were studied.Results: Two of 77 (2.6%) newborns with HCAM e 6/73 (8.2%) without it presented SNHL at 6 months of corrected age (p?=?0.16). Multivariable logistic regression analysis identified surgical ligation of patent ductus arteriosus (PDA) as independent predictors of SNHL (OR: 5.75, 95% CI 1.34–24.84, p?=?0.02), whereas the effect of HCAM on SNHL was only near to statistical significance level.Conclusions: Surgical ligation of PDA is associated with an increased risk of SNHL in VLBW infants, regardless of HCAM. 相似文献
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10.
Kimberly M. Kelly Mayank Ajmera Sandipan Bhattacharjee Rini Vohra Gerry Hobbs Lubna Chaudhary Jame Abraham Doreen Agnese 《Patient education and counseling》2013