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41.
Introduction: Changes in muscle architecture induced by eccentric knee extensor training remain unclear, as well the adaptive responses of synergistic knee extensor muscles with different geometrical designs. Methods: Ultrasonography images were taken from rectus femoris (RF) and vastus lateralis (VL) of 20 male volunteers before and after a non‐training control period of 4 weeks, and additional evaluations were performed after 4, 8, and 12 weeks of isokinetic eccentric training. Results: RF and VL had significant changes in muscle architecture within the first 4 training weeks, and the adaptive response throughout the intervention was similar. Muscle thickness increased by around 7–10%, fascicle length increased 17–19%, and pennation angle was unchanged. Conclusions: Increased muscle thickness due to eccentric training was related to increased fascicle length and not to pennation angle changes. Although RF and VL have a different fascicular geometry, they had similar morphological adaptations to eccentric training. Muscle Nerve 48 : 498–506, 2013  相似文献   
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This in vitro study evaluated the ability of a warm gutta-percha obturation system Thermafil to fill lateral channels in presence/absence of smear layer. Forty single-rooted extracted human teeth were randomly divided into two groups for which different irrigation regimens were used: group A, 5 ml of 5% NaOCl + 2.5 ml of 3.6% H2O2; group B, 5 ml of 5% NaOCl 5% + 2.5 ml of 17% ethylenediamine tetraacetic acid. A conventional crown-down preparation technique was employed. Obturation was performed using epoxy resin-based cement (AH Plus) and a warm gutta-percha plastic carrier system (Thermafil). Specimens were cleared in methyl salicylate and analyzed under a stereomicroscope to evaluate the number, length, and diameter of lateral channels. Lateral channels were identified in both groups at medium and apical thirds. Additional samples were prepared for scanning electron microscopy inspection to confirm the presence of smear layer in group A, and the absence of smear layer in group B. All lateral channels resulted filled in both groups. No statistically significant differences regarding number, length, and diameter were observed between the two groups. Smear layer did not prevent the sealing of lateral channels.  相似文献   
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The aim of this study was to investigate the effect of anethole (AN) and eugenol (EUG) on leukocyte migration using in vitro chemotaxis and in situ microcirculation assays. BALB/c mice were used for the in vitro chemotaxis assay, and Wistar rats for the in situ microcirculation assay. We evaluated (a) the in vitro leukocyte migration in response to chemotactic factors (formyl-methionyl-leucyl-phenylalanine [fMLP] and leukotriene B4 [LTB4]) and (b) the rolling, adhesion, and migration of leukocytes induced by an injection of carrageenan (100 µg/cavity) into the scrotum of the animal. In the in vitro chemotaxis assay, AN and EUG at doses of 1, 3, 9, and 27 µg/ml significantly inhibited leukocyte migration when stimulated by the chemotactic agents fMLP and LTB4. In the in situ microcirculation assay, AN at doses of 125 and 250 mg/kg and EUG at a dose of 250 mg/kg significantly decreased the number of leukocytes that rolled, adhered, and migrated to perivascular tissue. The results indicate that AN and EUG exert inhibitory effects on leukocyte migration, highlighting their possible use to diminish excessive leukocyte migration in the inflammatory process.  相似文献   
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von Melchner  H; Metcalf  D; Mandel  TE 《Blood》1980,56(5):917-922
After lethal irradiation of C57BL mice followed by the injection of 10(7) marrow cells, total cellularity and progenitor cell levels exceeded pretreatment levels within 12 days in the spleen, but regeneration remained incomplete in the marrow. The exceptional regenerative capacity of progenitor populations in the spleen was observed in organ cultures of spleen slices prepared 24 hr after irradiation and transplantation, excluding continuous repopulation from the marrow as a significant factor in splenic regeneration.  相似文献   
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OBJECTIVES: The aim of the study was the pathological and immunohistochemical analysis of cytokeratin 13 (CK13) in intraepithelial cervical tumors. STUDY DESIGN: We studied 415 in situ squamous carcinomas and 13 in situ mucinous cervical type adenocarcinomas of the uterine cervix. All patients underwent laser cervical conization and had a follow-up ranging 12-135 months. RESULTS: 3% of the squamous carcinoma patients recurred during the follow-up period, while the percentage of recurrence of in situ adenocarcinoma patients was 7.6%. We observed positive surgical edges in 46.1% of glandular tumors, and in 5% of squamous tumors. The percentage of recurrence was high among the cases with positive borders independently from their histopathologic type (14.3% in the squamous carcinomas versus 50% in the adenocarcinomas), compared to cases with negative edges (2.3% in the squamous carcinomas versus 0% in the adenocarcinomas). We observed CK13 positive staining in cervical squamous tumors and in mucinous cervical type adenocarcinomas, while there was no positive staining in non-neoplastic cervical glandular elements. CONCLUSION: CK13 positive immunostaining among in situ squamous and in situ mucinous cervical type adenocarcinoma cases adds additional evidence to data supporting a common origin of the two lesions.  相似文献   
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Italian legislation regarding reproductive medicine limits the number of embryos transferred per attempt to three. Thus, in order to achieve pregnancy, more IVF cycles may be required, generating a need for methods of ovarian stimulation with fewer side effects. The gonadotrophin-releasing hormone (GnRH) antagonists have several advantages in this respect, but there is a debate regarding a possible lower pregnancy rate from resulting cycles. This study evaluated the clinical applicability of GnRH antagonists for ovarian stimulation in young women undergoing intracytoplasmic sperm injection (ICSI) in which only three oocytes can be fertilized. The 200 women treated with GnRH antagonist had a significantly shorter stimulation and lower gonadotrophin consumption, oestradiol concentration, total and mature oocyte recovery as compared with 200 matched controls treated with GnRH agonist. No differences were found between the groups in the number of normal zygotes, total cleaved, transferred and high quality embryos, or in the clinical outcomes. Thus, the previously reported lower pregnancy rate in GnRH antagonist cycles may be related to the oocyte characteristics. Finally, under conditions of oocyte number restriction, the GnRH antagonist-based cycles may be proposed as an efficacious, safe and minimally invasive alternative to GnRH agonist in a standard long protocol.  相似文献   
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