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1.
Ying Yong Sheng Tai Xue Bao ; 32(10): 3405-3414, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34676701

RESUMO

In the context of global warming, the increases of temperature may affect tree growth and thus disturb ecosystem balance. In this study, we explored the main limiting factors for radial growth of Pinus sylvestris var. mongolica and Larix gmelinii in the Mohe area of Greater Khingan Mountains by using growth-climate response function analysis and moving correlation analysis, as well as the interspecific difference of the responses of radial growth to rapid warming. The results showed that the radial growth of P. sylvestris var. mongolica and L. gmelinii was affected by both temperature and precipitation. P. sylvestris var. mongolica was more sensitive to climate change than L. gmelinii, and its sensitivity to climate factors was more stable than L. gmelinii. The radial growth of P. sylvestris var. mongolica was significantly positively correlated with the monthly mean temperature and the monthly mean minimum temperature of the growing season, while that of L. gmelinii was significantly positively correlated with the monthly mean temperature and the monthly mean maximum temperature of winter. Precipitation in winter promoted the growth of P. sylvestris var. mongolica, whereas precipitation in the late growing season of the previous year inhibited the radial growth of L. gmelinii. After the rapid warming in 1990, the limiting effect of precipitation on P. sylvestris var. mongolica changed from negative to significantly positive, with the inhibition effect of high temperature being greater than the promotion effect. The inhibitory effect of high temperature on L. gmelinii was enhanced, and the limiting effect of precipitation on L. gmelinii was also enhanced after heating up. The growth rate decreased significantly, with obvious difference being observed in the correlations between the growth rate of two species with temperature and precipitation. Our results could provide scientific basis for forest ecosystem management and protection in Greater Khingan Mountains.


Assuntos
Larix , Pinus sylvestris , Pinus , China , Mudança Climática , Ecossistema , Florestas , Árvores
2.
Chin J Cancer ; 29(11): 914-22, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20979690

RESUMO

BACKGROUND AND OBJECTIVE: In computed tomography (CT)-based radiotherapy planning for prostate cancer, it is difficult to precisely delineate the prostatic apex because of its relationship with the urogenital diaphragm and bulbospongiosus musculature. In this retrospective study, we analyzed the magnetic resonance imaging (MRI) and CT scans of the patients with prostate cancer to investigate the relationship between the prostatic apex and the anatomic structure visible on CT, and to provide evidence for localizing the prostatic apex in radiotherapy planning. METHODS: MRI and CT scans of 108 patients with prostate cancer were analyzed to measure the distances between the prostatic apex and the bottom of ischial tuberosities, the bottom of obturator foramen, the bottom of pubic symphysis, and the bulb of the penis. The volume of the prostate was measured to analyze its relationship with the localization of the prostatic apex. RESULTS: The prostatic apex was located (13.1±3.3) mm above the bulb of the penis, (11.0±5.4) mm above the bottom of the obturator foramen, (31.3±5.5) mm above the ischial tuberosities, and (7.1±4.7) mm above the bottom of the symphysis pubis. There was no correlation between the size of the prostate and the localization of the prostatic apex. CONCLUSIONS: The variance of the distance between the prostatic apex and the bulb of the penis is smaller than that of the distance between the apex and bony anatomy. Delineating the target to 6 mm above the bulb of the penis can cover the prostatic apex in 95% of the patients with prostate cancer, delineating to the bottom of obturator foramen can cover the prostatic apex in 100% of the patients.


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada por Raios X/métodos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pênis/diagnóstico por imagem , Pênis/patologia , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/radioterapia , Osso Púbico/diagnóstico por imagem , Osso Púbico/patologia
3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 42(6): 767-72, 2010 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-21170112

RESUMO

OBJECTIVE: To compare efficacy of plain and contrast enhancement MRI (1.5T or 3T) and dynamic contrast enhanced multidetector CT (MDCT, 16- or 64 -slice) for the detection of small hepatocellular carcinoma (HCC) in patients with hepatitis B-induced cirrhosis. METHODS: A total of 21 patients (18 men, 3 women; age range, 44-74 years) with 22 small HCC and liver cirrhosis were enrolled, all having undergone MDCT and MRI within one month. The diagnosis of small HCC was established at surgical resection (n=4), percutaneous biopsy (n=1), with positive tumor staining at intervention or from combined clinical data, typical imaging features and follow-up for a period of at least one year. Triple-phase or dual-phase dynamic contrast enhancement was performed on a 16- or 64-slice MDCT. MRI sequences included transverse T1-weighed images acquired as fast spoiled gradient (FSPGR) in-phase and out-of-phase dual-echo, transverse T2-weighed images with respiratory triggering acquired as fat-suppressed fast spin echo (FSE) or fast recovery fast spin echo (FRFSE), and breath-hold coronal T2-weighed images acquired as single shot fast spin echo (SSFSE) or fast imaging employing steady-state acquisition (FIESTA). CT and MRI observers independently analyzed each image in random order and marked each lesion detected with a score, ranking from 1 to 5 (1 definitely benign, 2 possibly benign, 3 undetermined, 4 possible HCC, and 5 definite HCC), then receiver operating characteristic (ROC) curve and Chi-square analysis were adopted to compare the efficacy for MDCT and MRI imaging. RESULTS: Although no significant difference was demonstrated at the comparison of sensitivity and specificity (sensitivity and specificity of MDCT: 70%, 50%; sensitivity and specificity of MRI 86.36%, 100%; sensitivity χ2=0.835, P=0.360; specificity χ2=1.379, P=0.240), the Az (area under the ROC curve) for MRI imaging (mean, 0.974) was much higher than that for MDCT (mean, 0.795) with significant difference (P<0.05). CONCLUSION: MRI imaging shows better diagnostic accuracy for the detection of small HCC in patients with hepatitis B-induced cirrhosis and is recommended to improve the detection and diagnosis.


Assuntos
Hepatite B Crônica/complicações , Cirrose Hepática/complicações , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética , Tomografia Computadorizada Espiral , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/etiologia , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Neoplasias Hepáticas/etiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Espiral/métodos
4.
Beijing Da Xue Xue Bao Yi Xue Ban ; 41(4): 469-73, 2009 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-19727241

RESUMO

Prostatic carcinoma is the fifth most common cancer in the world and the second most common in men. It is quite important to early detect and diagnose prostate cancer to reduce the mortality. With the increasing of the diagnosis and treatment tasks of prostate cancer and the development of medical techniques, more and more clinical and lab examinations, biopsy and medical imaging techniques are included in the diagnosis of prostate cancer. Although these examination results are supplement to each other, there are contradictions among them at the same time. Artificial neural networks (ANNs) which can perform multifactorial analysis based on computational methodologies have been widely used in the prognosis of prostate cancer. The current application of ANNs is reviewed.


Assuntos
Diagnóstico por Computador/métodos , Redes Neurais de Computação , Neoplasias da Próstata/diagnóstico , Diagnóstico por Imagem , Técnicas e Procedimentos Diagnósticos , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Valor Preditivo dos Testes
5.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 25(6): 1611-1614, 2017 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-29262884

RESUMO

OBJECTIVE: To investigate the changes of peripheral blood marrow-derived suppressor cell level after chemotherapy induction remission by regimen consisting of vincristine, daunorubicin, L-asparaginase and prednisone (VDLP) and to analyze their relationship with immume system in B-ALL children. METHODS: Thirty B-ALL children after induction remission by VDLP regimen from August 2015 to August 2016 were selected as B-ALL group and 30 normal healthy children were selected as control group. The peripheral blood in 2 groups was collected and detected by flow cytometry, then the ratios of CD30+ cells and CD33+ HLA-DR- marrow-derived suppressor cells, CD14+CD33+HLA-DR- marrow-derived suppressor cells and CD15+CD33+HLA-DR- marrow-derived suppressor cells were calculated, and their changes after induction remission by VDLP regimen and the relationship with immune system were analyzed. RESULTS: After treatment the ratio of CD33+ cells in peripheral blood of B-ALL group and control group was not significantly different (P> 0.05), moreover, the ratio of CD33+ cells in B-ALL group was significantly higher than that before treatment (P<0.05), while the ratios of CD33+ HLA-DR- marrow-derived suppressor cells, CD14+CD33+HLA-DR- marrow-derived suppressor cells and CD15+CD33+HLA-DR- marrow-derived suppressor cells in B-ALL group were significantly lower than those in control group (all P<0.05), but the ratios of these cells in B-ALL group were higher than those before treatment, and yet there was no statistical significance (P>0.05). CONCLUSION: The ratios of marrow-derived suppressor cells in peripheral blood of B-ALL children in complete remission after treatment with VDLP regimen are higher than those before treatment, but are significantly lower than normal value, which may be related with non-complese recovery of immune system in B-ALL children after treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células da Medula Óssea , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Antígenos CD , Medula Óssea , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Linfócitos T CD8-Positivos , Criança , Citometria de Fluxo , Antígenos HLA-DR , Humanos , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico
6.
Environ Int ; 88: 133-141, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26735351

RESUMO

The incidence of breast cancer is related to various risk factors, especially that the environmental and lifestyle factors account for major contribution at the rate of 70% to 95% over all. However, there still remains some controversy over the epidemiological evidence regarding the effects of environmental carcinogens on the risk of breast cancer. We conducted a quantitative meta-analysis aiming at full evaluation of the effects of polychlorinated biphenyls (PCBs) on breast cancer in a congener-specific fashion. Four online literature databases were systematically searched before 1st January 2015, for studies stating correlation between PCB congeners and breast cancer. The Newcastle-Ottawa Scale was used to evaluate the quality of the studies that were included in our analysis. Sixteen studies were included in our final meta-analysis after screening based on the priori inclusion criteria. Nine PCB congeners were reported by more than two studies and they were presented in detail. The pooled Odds Ratios (ORs) showed a significant increase in the risk of breast cancer in individuals with higher plasma/fat levels of PCB 99 (OR: 1.36; 95% CI: 1.02 to 1.80), PCB 183 (OR: 1.56; 95% CI: 1.25 to 1.95) and PCB 187 (OR: 1.18; 95% CI: 1.01 to 1.39). Besides, the outcomes did not support a relationship between dioxin-like PCB congeners and the risk of breast cancer. The results of our meta-analysis imply that PCB 99, PCB 183 and PCB 187 would increase the risk of breast cancer. The mechanism of this increased risk may be by the induction of the CYP2B family in cytochrome P450 enzymes.


Assuntos
Neoplasias da Mama/induzido quimicamente , Poluentes Ambientais/toxicidade , Bifenilos Policlorados/toxicidade , Neoplasias da Mama/epidemiologia , Poluentes Ambientais/análise , Feminino , Humanos , Incidência , Razão de Chances , Bifenilos Policlorados/análise , Fatores de Risco
7.
Zhonghua Yi Xue Za Zhi ; 83(24): 2158-61, 2003 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-14720426

RESUMO

OBJECTIVE: To investigate the mechanisms of two novel missense mutations of factor XIIIA subunit gene (Arg77-->Cys,Ser413-->Trp) in the pathogenesis of hereditary factor XIII deficiency. METHODS: Site-directed mutagenesis was conducted to obtain 2 mutant human XIII A recombinant plasmids, mut-PCI/FXIIIA. Normal wild type factor XIII A recombinant plasmid, wt-PCI/FXIIIA, and mut-PCI/FXIIIA, were transfected into cultured COS7 cells line, renal fibroid cell of African green monkey using Superfect reagent respectively, The expression levels of DNA, RNA and protein of human factor XIII, both wild type and mutant, were detected by PCR, RT-PCR and Western blotting. Pulse-chase experiment was used to look into the changing of factor XIII A in the cytoplasm. Factor XIIIA activity was assayed by Biotin-pentylamine incorporation technique. RESULTS: The mRNA levels of the two mutants in transfected cells were similar to that of the wild type factor XIIIA. But the amount of mutant factor XIIIA protein and its activity in cells decreased markedly, even disappeared. Pulse-chase experiment revealed that at the two mutants existed chase time 0.5 h and 1 h considerable amounts in cells and then disappeared rapidly later. CONCLUSION: The 2 mutations of the factor XIIIA cause the instability, degradation, and rapid disappearance of FXIIIA in cytoplasm, thus resulting in hereditary factor XIII deficiency.


Assuntos
Deficiência do Fator XIII/genética , Fator XIII/genética , Mutação , Animais , Células COS , Fator XIII/química , Humanos , RNA Mensageiro/análise
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