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101.
Progesterone (P4) can participate in the development of female mammalian antral follicles through nuclear receptor (PGR). In this experiment, the differences of P4 synthesis and PGR expression in different developmental stages of sheep antral follicles (large > 5mm, medium 2-5mm, small < 2mm) were detected by enzyme-linked immunosorbent assay, immunohistochemistry, qRT-PCR and Western blotting. Secondly, sheep follicular granulosa cells were cultured in vitro. The effects of different concentrations of FSH and LH on P4 synthesis and PGR expression were studied. The results showed that acute steroid regulatory protein (StAR), cholesterol side chain lyase (P450scc) and 3β Hydroxysteroid dehydrogenase (3β-HSD) and PGR were expressed in antral follicles, and with the development of antral follicles in sheep, StAR, P450scc and the expression of 3β-HSD and PGR increased significantly. In vitro experiments showed that FSH and LH alone or together treatment could regulate P4 secretion and PGR expression in sheep follicular granulosa cells to varying degrees, hint P4 and PGR by FSH and LH, and LH was the main factor. Our results supplement the effects of FSH and LH on the regulation of P4 synthesis during follicular development, which provides new data for further study of steroid synthesis and function in follicular development.  相似文献   
102.
The hippocampus is crucial for higher brain functions, such as learning, memory, and emotion. Many diseases like epilepsy and Down's syndrome are associated with abnormalities in early hippocampal development. In addition, adult dentate neurogenesis is thought to be defective in several classes of psychiatric disorders. However, the mechanisms regulating hippocampal development and adult neurogenesis remain unclear. One of the limitations to studying these processes is the scarcity of available specific mouse tools. Here, we report an inducible transgenic Cre mouse line, Frizzled 9‐CreER?, in which tamoxifen administration induces Cre recombinant. Our data show that Cre is expressed in the developing hippocampal primordium, confined to the granule cell layer at P20 and further limited to the subgranular zone in the adult dentate gyrus. Cre recombinase shows very high activity in all of these regions. Thus, this transgenic line will be a powerful tool in understanding the mechanisms of hippocampal development, adult neurogenesis, and associated diseases. genesis 49:919–926, 2011. © 2011 Wiley Periodicals, Inc.  相似文献   
103.
<正>Cytokinesis is the final stage of cell division that generates two daughter cells(Fededa and Gerlich,2012).The textbook version di-vides the plant and animal cell cytokinesis into two categories.Plant cells form a mid-zone phragmoplast via vesicle delivering and fusion,and cell wall materials are thus deposited.Animal cells form actomyosin contractile rings,which are the sole force that drives abscission.However,recent evidence has been mounting and pinpointing a pivotal role of membrane transport and subse-  相似文献   
104.

Purpose

The purpose of this retrospective study was to identify the independent prognostic factors and optimize the treatment for nasopharyngeal carcinoma (NPC) patients with distant metastasis at initial diagnosis.

Methods

A total of 234 patients referred between January 2001 and December 2010 were retrospectively analyzed. Among the 234 patients, 94 patients received chemotherapy alone (CT), and 140 patients received chemoradiotherapy (CRT). Clinical features, laboratory parameters and treatment modality were examined with univariate and multivariate analyses.

Results

The median overall survival (OS) time was 22 months (range, 2-125 months), and the 1-year, 2-year, 3-year overall survival rates were 82.2%, 51.3% and 34.1%. The overall response and disease control rates of metastatic lesions after chemotherapy were 56.0% and 89.8%. The factors associated with poor response were karnofsky performance score (KPS) <80, liver metastasis, lactate dehydrogenase (LDH)>245 IU/L, and number of chemotherapy cycles <4. The 3-year OS of patients receiving CRT was higher than those receiving CT alone (48.2% vs. 12.4%, p<0.001). Subgroup analysis showed that significantly improved survival was also achieved by radiotherapy of the primary tumor in patients who achieved complete remission (CR)/partial remission (PR) or stable disease (SD) of metastatic lesions after chemotherapy. Significant independent prognostic factors of OS were KPS, liver metastasis, levels of LDH, and multiple metastases. Treatment modality, response to chemotherapy and chemotherapy cycles were also associated with OS.

Conclusion

A combination of radiotherapy and chemotherapy seems to have survival benefits for selected patients with distant metastases at initial diagnosis. Clinical and laboratory characteristics can help to guide treatment selection. Prospective randomized studies are needed to confirm the result.  相似文献   
105.
Time course and mutational analyses were used to examine the accumulation in protoplasts of progeny RNAs of the bipartite Crinivirus, Lettuce infectious yellow virus (LIYV; family Closteroviridae). Hybridization analyses showed that simultaneous inoculation of LIYV RNAs 1 and 2 resulted in asynchronous accumulation of progeny LIYV RNAs. LIYV RNA 1 progeny genomic and subgenomic RNAs could be detected in protoplasts as early as 12 h postinoculation (p.i.) and accumulated to high levels by 24 h p.i. The LIYV RNA 1 open reading frame 2 (ORF 2) subgenomic RNA was the most abundant of all LIYV RNAs detected. In contrast, RNA 2 progeny were not readily detected until ca. 36 h p.i. Mutational analyses showed that in-frame stop codons introduced into five of seven RNA 2 ORFs did not affect accumulation of progeny LIYV RNA 1 or RNA 2, confirming that RNA 2 does not encode proteins necessary for LIYV RNA replication. Mutational analyses also supported that LIYV RNA 1 encodes proteins necessary for replication of LIYV RNAs 1 and 2. A mutation introduced into the LIYV RNA 1 region encoding the overlapping ORF 1B and ORF 2 was lethal. However, mutations introduced into only LIYV RNA 1 ORF 2 resulted in accumulation of progeny RNA 1 near or equal to wild-type RNA 1. In contrast, the RNA 1 ORF 2 mutants did not efficiently support the trans accumulation of LIYV RNA 2. Three distinct RNA 1 ORF 2 mutants were analyzed and all exhibited a similar phenotype for progeny LIYV RNA accumulation. These data suggest that the LIYV RNA 1 ORF 2 encodes a trans enhancer for RNA 2 accumulation.  相似文献   
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110.

Objective

To study the mechanism of the no-reflow phenomenon using coronary angiography (CAG) and intravascular ultrasound (IVUS).

Methods

A total of 120 patients with acute myocardial infarction (AMI) who successfully underwent indwelling intracoronary stent placement by percutaneous coronary intervention (PCI). All patients underwent pre- and post-PCI CAG and pre-IVUS. No-reflow was defined as post-PCI thrombolysis in myocardial infarction (TIMI) grade 0, 1, or 2 flow in the absence of mechanical obstruction. Normal reflow was defined as TIMI grade 3 flow. The pre-operation reference vascular area, minimal luminal cross-sectional area, plaque cross-sectional area, lesion length, plaque volume and plaque traits were measured by IVUS.

Results

The no-reflow group was observed in 14 cases (11.6%) and normal blood-flow group in 106 cases (89.4%) based on CAG results. There was no statistically significant difference in the patients’ medical history, reference vascular area (no-flow vs. normal-flow; 15.5 ± 3.2 vs. 16.2 ± 3.3, p> 0.05) and lesion length (21.9 ± 5.1 vs. 19.5 ± 4.8, p> 0.05) between the two groups. No-reflow patients had a longer symptom onset to reperfusion time compared to normal blood-flow group [(6.6 ± 3.1) h vs (4.3 ± 2.7) h; p< 0.05] and higher incidence of TIMI flow grade< 3 (71.4% vs 49.0%, p< 0.05). By IVUS examination, the no-reflow group had a significantly increased coronary plaque area and plaque volume compared to normal blood-flow group [(13.7 ± 3.0) mm2 vs (10.2 ± 2.9) mm2; (285.4 ± 99.8) mm3 vs (189.7 ± 86.4) mm3; p< 0.01]. The presence of IVUS-detected soft plaque (57.1% vs. 24.0%, p< 0.01), eccentric plaque (64.2% vs. 33.7%, p< 0.05), plaque rupture (50.0% vs. 21.2%, p< 0.01), and thrombosis (42.8% vs. 15.3%) were significantly more common in no-reflow group.

Conclusion

There was no obvious relationship between the coronary risk factors and no-reflow phenomenon. The symptom onset to reperfusion time, TIMI flow grade before stent deployment, plaque area, soft plaques, eccentric plaques, plaque rupture and thrombosis may be risk factors for the no-reflow phenomenon after PCI.  相似文献   
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