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1.
Oncol Lett ; 25(3): 120, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36910910

RESUMO

A vaginal yolk sac tumor (YST) is a rare malignant germ cell tumor for infants and children, and it has been >50 years since the first case was reported. The treatment strategy has changed markedly in the past 50 years, from radical surgical treatment to conservative surgery combined with chemotherapy, and then to combined chemotherapy alone. The present study reports the case of a primary vaginal YST in a 13-month-old girl that was successfully treated by tumor resection combined with chemotherapy. The clinical symptoms, imaging features and treatment characteristics are described in detail, as well as the postoperative treatment. There was no local recurrence or metastasis for the 2 years of follow-up to date. A literature review was also conducted to investigate the clinicopathological features, treatment and prognosis of this tumor. Overall, surgery combined with bleomycin, etoposide and carboplatin combination chemotherapy can be an effective option for vaginal YST.

2.
Opt Express ; 30(9): 14839-14850, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473219

RESUMO

Topological photonics offers the possibility of robust transport and efficiency enhancement of information processing. Terahertz (THz) devices, such as waveguides and beam splitters, are prone to reflection loss owing to their sensitivity to defects and lack of robustness against sharp corners. Thus, it is a challenge to reduce backscattering loss at THz frequencies. In this work, we constructed THz photonic topological insulators and experimentally demonstrated robust, topologically protected valley transport in THz photonic crystals. The THz valley photonic crystal (VPC) was composed of metallic cylinders situated in a triangular lattice. By tuning the relevant location of metallic cylinders in the unit cell, mirror symmetry was broken, and the degenerated states were lifted at the K and K' valleys in the band structure. Consequently, a bandgap of THz VPC was opened, and a nontrivial band structure was created. Based on the calculated band structure, THz field distributions, and valley Berry curvature, we verified the topological phase transition in such type of THz photonic crystals. Further, we showed the emergence of valley-polarized topological edge states between the topologically distinct VPCs. The angle-resolved transmittance measurements identified the bulk bandgap in the band structure of the VPC. The measured time-domain spectra demonstrated the topological transport of valley edge states between distinct VPCs and their robustness against bending and defects. Furthermore, experiments conducted on a topological multi-channel intersectional device revealed the valley-polarized characteristic of the topological edge states. This work provides a unique approach to reduce backscattering loss at the THz regime. It also demonstrates potential high-efficiency THz functional devices such as topologically protected beam splitters, low-loss waveguides, and robust delay lines.

3.
Neural Netw ; 102: 36-47, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29524766

RESUMO

Least square regression is a very popular supervised classification method. However, two main issues greatly limit its performance. The first one is that it only focuses on fitting the input features to the corresponding output labels while ignoring the correlations among samples. The second one is that the used label matrix, i.e., zero-one label matrix is inappropriate for classification. To solve these problems and improve the performance, this paper presents a novel method, i.e., inter-class sparsity based discriminative least square regression (ICS_DLSR), for multi-class classification. Different from other methods, the proposed method pursues that the transformed samples have a common sparsity structure in each class. For this goal, an inter-class sparsity constraint is introduced to the least square regression model such that the margins of samples from the same class can be greatly reduced while those of samples from different classes can be enlarged. In addition, an error term with row-sparsity constraint is introduced to relax the strict zero-one label matrix, which allows the method to be more flexible in learning the discriminative transformation matrix. These factors encourage the method to learn a more compact and discriminative transformation for regression and thus has the potential to perform better than other methods. Extensive experimental results show that the proposed method achieves the best performance in comparison with other methods for multi-class classification.


Assuntos
Aprendizado de Máquina , Análise dos Mínimos Quadrados
5.
Int J Clin Exp Med ; 8(1): 73-85, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25784976

RESUMO

OBJECTIVE: A meta-analysis was carried out to summarize published data on the relationship between breast cancer and dietary factors. METHODS: Databases in Chinese (China National Knowledge Infrastructure [CNKI], China Biology Medicine [CBM], WanFang, VIP) and in English (PubMed and Web of Science) were searched for articles analyzing vegetable, fruit, soy food and fat consumption and breast cancer risk published through June 30, 2013. Random effects models were used to estimate summary odds ratios (OR) based on high versus low intake, and subgroup analysis was conducted according to region, study design, paper quality and adjustment for confounding factors to detect the potential source of heterogeneity. Every study was screened according to the inclusion criteria and exclusion criteria, evaluated in accordance with the Newcastle-Ottawa Scale. RevMan 5.2 software was used for analysis. RESULTS: Of 785 studies retrieved, 22 met inclusion criteria (13 in Chinese and 9 in English), representing 23,201 patients: 10,566 in the experimental group and 12,635 in the control group. Thirteen included studies showed vegetables consumption to be a relevant factor in breast cancer risk, OR = 0.77 (95% CI [confidence interval] 0.62-0.96). Eleven studies showed fruits consumption to be relevant, OR = 0.68 (95% CI 0.49-0.93). Significant differences were also found between those who consumed soy foods, OR = 0.68 (95% CI 0.50-0.93) and those who ate a high-fat diet, OR = 1.15 (95% CI 1.01-1.30). CONCLUSION: This analysis confirms the association between intake of vegetables, fruits, soy foods and fat and the risk of breast cancer from published sources. It's suggested that high consumption of vegetables, fruits and soy foods may reduce the risk of breast cancer, while increasing fat consumption may increase the risk.

6.
Ultrasound Med Biol ; 40(9): 2064-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25023108

RESUMO

The aim of this study was to investigate the vertebral artery (VA) morphology of enlistment-age male student pilots with ultrasound to provide a basis for early diagnosis of potentially asymptomatic cervical vertigo. Ultrasound results of the origin position, diameter and hemodynamics of the VA in 935 cases of student pilots with a mean age of 18.0 y were analyzed. The inner diameters of both sides of the VA differ: the left is larger than the right statistically (p < 0.001). Moreover, the peak systolic velocity of the left VA is significantly greater than that of the right (p < 0.001). Congenital VA anomalies in age-appropriate male student pilots included inner diameter variation, course variation and origin position variation. The incidence of course variation or origin position proportion was low (3.46%, 32/925), and origin position variation was often accompanied by inner diameter variation or course variation. This study confirms that there are a variety of congenital abnormalities in the vertebral arteries of enlistment-age male student pilots, and a VA diameter <2.5 mm may be a reasonable criterion for diagnosis of VA hypoplasia.


Assuntos
Artéria Vertebral/diagnóstico por imagem , Adolescente , Adulto , Aeronaves , Velocidade do Fluxo Sanguíneo , China , Hemodinâmica , Humanos , Masculino , Estudantes , Ultrassonografia , Artéria Vertebral/anatomia & histologia , Artéria Vertebral/fisiologia , Adulto Jovem
7.
Int J Clin Exp Med ; 7(12): 5547-52, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25664069

RESUMO

Although many epidemiologic studies have investigated the FXIII-A Val34Leu polymorphism and their associations with myocardial infarction (MI), definite conclusions can't be drawn. To clarify the effects of FXIII-A Val34Leu polymorphism on the risk of MI, a meta-analysis was performed. Related studies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) till 10 August 2014. Pooled ORs and 95% CIs were used to assess the strength of the associations. A total of 12 studies including 3139 MI cases and 6343 healthy controls were involved in this meta-analysis. A significantly decreased MI risk was found (adjusted OR = 0.70, 95% CI 0.60-0.82, P < 0.00001). In the subgroup analysis by age, significantly decreased risks were found in the young population (OR = 0.70, 95% CI 0.54-0.91, P = 0.008) and old population (OR = 0.63, 95% CI 0.50-0.80, P = 0.0001). In the subgroup analysis by gender, significantly decreased risks were found in male (OR = 0.55, 95% CI 0.34-0.88, P = 0.01) and female (OR = 0.72, 95% CI 0.55-0.95, P = 0.02). When we limited the meta-analysis to studies that controlled for confounders such as age, sex, BMI, smoking, diabetes, hypertension, dyslipidemia, and fibrinogen, a significant association between FXIII-A Val34Leu polymorphism and MI risk remained. This meta-analysis provides the evidence that FXIII-A Val34Leu polymorphism may significant associated with the MI risk.

8.
Di Yi Jun Yi Da Xue Xue Bao ; 22(4): 312-5, 2002 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12390731

RESUMO

OBJECTIVE: To detect the expression of recombinant human bone morphogenetic protein7 (rhBMP7) in skeletal muscle satellite cells (SMSCs) with rhBMP7 gene transfection mediated by retroviral vector. METHODS: rhBMP7 gene was reconstructed in retroviral vector and transferred into packaging cells PT67 via liposome reagent, with the positive cell clones selected with G418. In vitro cultured SMSCs were transfected with the virus granules secreted by PT67 cells and followed by G418 selection. Reverse transcriptase-polymerase chain reaction was utilized for analysis for rhBMP7 mRNA in the transfected cells. RESULTS: rhBMP7 retrovirus vector was successfully constructed and transferred into PT67 cells, and abundant mRNA expression of rhBMP7 was observed in the skeletal muscle satellite cells transfected with the virus and selected with G418. CONCLUSION: rhBMP7 gene can be transferred into the skeletal muscle satellite cells via retroviral vector to yield effective rhBMP7 mRNA expression.


Assuntos
Proteínas Morfogenéticas Ósseas/biossíntese , Músculo Esquelético/metabolismo , Fator de Crescimento Transformador beta , Transgenes/fisiologia , Animais , Proteína Morfogenética Óssea 7 , Proteínas Morfogenéticas Ósseas/genética , Feminino , Vetores Genéticos/genética , Humanos , Masculino , Músculo Esquelético/fisiologia , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Retroviridae/genética , Transfecção
9.
Di Yi Jun Yi Da Xue Xue Bao ; 22(6): 509-11, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12297470

RESUMO

OBJECTIVE: To establish appropriate animal models for observing the effects of X-ray irradiation on limb allograft rejection. METHODS: Wistar rats were used as donators and SD rats as recipients, the latter divided into 2 groups, namely irradiation group and non-irradiation group according to pretransplant treatment with or without X-ray radiation (5 Gy) on the part of the donators. The donor limbs were transplanted into SD rats who had their own limbs cut off, and the sciatic nerve, femoral nerve, and femoral artery and femoral vein were anastomosed in operation. After the operation, all the recipients were given benzathine benzylpenicillin, and their vital signs, together with changes of the allografts, observed. RESULTS: A total of 16 rats received transplantation that was successful in 6 rats of non-radiation group and 7 of irradiation group. The graft survival averaged 12.0+/-2.4 d in non-irradiation group and 24.7+/-8.1 d in irradiation group, showing significant difference in the lengths of survival between the 2 groups (P<0.05). CONCLUSION: The graft survival time in rats can be significantly prolonged by pretransplant irradiation of the allograft, which also help control acute rejection of the allograft.


Assuntos
Extremidades/efeitos da radiação , Extremidades/transplante , Rejeição de Enxerto/prevenção & controle , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Transplante Homólogo , Raios X
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