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991.
Background: Previous studies have suggested that the human Y-chromosome haplogroup Q1a1a-M120, a widespread paternal lineage in East Asian populations, originated in South Siberia. However, much uncertainty remains regarding the origin, diversification, and expansion of this paternal lineage.

Aim: To explore the origin and diffusion of paternal Q-M120 lineages in East Asia.

Subjects and methods: The authors generated 26 new Y chromosome sequences of Q-M120 males and co-analysed 45 Y chromosome sequences of this haplogroup. A highly-revised phylogenetic tree of haplogroup Q-M120 with age estimates was reconstructed. Additionally, a comprehensive phylogeographic analysis of this lineage was performed including 15,007 samples from 440 populations in eastern Eurasia.

Results: An ancient connection of this lineage with populations in Siberia was revealed. However, this paternal lineage experienced an in-situ expansion between 5000 and 3000?years ago in northwestern China. Ancient populations with high frequencies of Q-M120 were involved in the formation of ancient Huaxia populations before 2000?years ago; this haplogroup eventually became one of the founding paternal lineages of modern Han populations.

Conclusion: This study provides a clear pattern of the origin and diffusion process of haplogroup Q1a1a-M120, as well as the role of this paternal lineage during the formation of ancient Huaxia populations and modern Han populations.  相似文献   
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993.

Purpose

Endobronchial metastasis is defined as documented extrathoracic malignancies metastatic to the endobronchus within a bronchoscopically visible range. Although the clinical and radiologic findings of endobronchial metastasis are similar to primary lung cancer, treatment and prognosis may be different. We hereby investigated the clinical, radiologic and bronchoscopic aspects of endobronchial metastases (EBM) in Korean patients.

Materials and Methods

A total of 43 patients with EBM who underwent bronchoscopic biopsies from June 1991 to December 2009 at Severance Hospital, Yonsei University College of Medicine in Seoul, Korea, were analyzed retrospectively. We evaluated clinical, radiologic and bronchoscopic characteristics of EBM.

Results

The patients consisted of 27 males and 16 females and their ages ranged from 18 to 77 years. The common primary cancers related to EBM were rectal (16.3%), colon (11.6%), breast (9.3%) and uterine (9.3%) cancers. The mean interval from diagnosis of primary cancer to EBM was 36 months, and the mean survival duration from diagnosis of EBM was 16.1 months in 33 deceased patients.

Conclusion

EBM develop in various types of malignancies at various times with unremarkable manifestations. Therefore, physicians should consider the possibility of EBM, especially if a patient has a history of any malignancy, regardless of respiratory symptoms. Respiratory symptoms related with EBM can be treated by various safe procedures.  相似文献   
994.
995.
The morphology of focal segmental glomerulosclerosis (FSGS) includes collapsing, cellular, and sclerosing forms. The Columbia Working Classification of FSGS divides these into collapsing (COLL), cellular (CELL), tip lesion (TIP), perihilar (PH), and not otherwise specified (NOS) morphologic forms. This study examined the ability of renal pathologists to classify FSGS using single light microscopic images of glomeruli as a uniform data set. Sixty-one digital images of individual glomeruli with FSGS, stained by periodic acid-Schiff or Jones methenamine silver methods, were classified independently by six specialist renal pathologists. Diagnostic consistency was quantified using the kappa statistic for nominal categories. Agreement for 366 diagnoses by six observers was 75.2 % with a kappa value of 0.676. Six of six observers agreed in 31 of 61 cases (50.8 %) and four or more in 53 cases (86.9 %). Respective kappa values ranged from moderate to good: COLL 0.77, CELL 0.53, TIP 0.76, PH 0.84, and NOS 0.60. Capillary retraction with lobular expansion, hypercellularity, and sclerosis in the same glomerular segments, and the location of segmental lesions were sources of diagnostic inconsistency. The morphologic forms of FSGS defined by the Columbia system are reproducible between observers and have a low probability of confusion between forms. Individual glomeruli may have overlapping features of more than one form of FSGS.  相似文献   
996.
997.
998.
Journal of Molecular Medicine - Immuno-environmental change triggers CD4+ T cell differentiation. T cell specialization activates metabolic signal pathways to meet energy requirements. Defective T...  相似文献   
999.
1000.
PurposeTo compare image quality in selective intracoronary contrast-injected computed tomography angiography (Selective-CTA) with that in conventional intravenous contrast-injected CTA (IV-CTA).Materials and MethodsSix pigs (35 to 40 kg) underwent both IV-CTA using an intravenous injection (60 mL) and Selective-CTA using an intracoronary injection (20 mL) through a guide-wire during/after percutaneous coronary intervention. Images of the common coronary artery were acquired. Scans were performed using a combined machine comprising an invasive coronary angiography suite and a 320-channel multi-slice CT scanner. Quantitative image quality parameters of CT attenuation, image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), mean lumen diameter (MLD), and mean lumen area (MLA) were measured and compared. Qualitative analysis was performed using intraclass correlation coefficient (ICC), which was calculated for analysis of interobserver agreement.ResultsQuantitative image quality, determined by assessing the uniformity of CT attenuation (399.06 vs. 330.21, p<0.001), image noise (24.93 vs. 18.43, p<0.001), SNR (16.43 vs. 18.52, p=0.005), and CNR (11.56 vs. 13.46, p=0.002), differed significantly between IV-CTA and Selective-CTA. MLD and MLA showed no significant difference overall (2.38 vs. 2.44, p=0.068, 4.72 vs. 4.95, p=0.078). The density of contrast agent was significantly lower for selective-CTA (13.13 mg/mL) than for IV-CTA (400 mg/mL). Agreement between observers was acceptable (ICC=0.79±0.08).ConclusionOur feasibility study in swine showed that compared to IV-CTA, Selective-CTA provides better image quality and requires less iodine contrast medium.  相似文献   
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