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1.
Biol Pharm Bull ; 42(2): 194-200, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30464092

RESUMO

Seventeen 13,28-epoxy triterpenoid saponins obtained from Ardisia gigantifolia STAPF. were evaluated their anti-proliferative activities on MCF-7 cells. The structure-activity relationship analysis indicated that CH3 group at C-30, four saccharide units with L-rhamnose at R6 in the sugar units are crucial for the cytotoxic activity on MCF-7. Compounds 1, 2, 6, 7, 12, and 14 were selected to identify the anti-proliferative activity on the other three breast cancer cell lines (T47D, MDA-MB-231 and SK-BR-3). Compounds 2, 6, and 7 with good activity on MCF-7 also showed activity on T47D, MDA-MB-231, and SK-BR-3. Compounds 12 and 14 without cytotoxic activity on MCF-7 almost showed no activities on the other three cell lines. For the triple-negative breast cancer MDA-MB-231, Saponins 7 and 14 showed selective cytotoxic activity, 7 showed much more activity than 14, suggesting the six saccharide units in sugar units and CH3 on C-30 were the key moieties for the anti-proliferative activities. Further molecular mechanism of saponin 7 was studied on inhibiting cell proliferation of MDA-MB-231 cells. Saponin 7 could enhance apoptosis, arrest cell cycles, decrease mitochondrial membrane potentials (MMPs), and considered the involvement of reactive oxygen species (ROS) may explain this conundrum.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ardisia/química , Neoplasias da Mama/tratamento farmacológico , Saponinas/farmacologia , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Saponinas/química , Saponinas/isolamento & purificação , Triterpenos/química , Triterpenos/isolamento & purificação
2.
Environ Monit Assess ; 189(11): 533, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28971264

RESUMO

The salinity stress inhibits the growth of Populus euphratica (P. euphratica), and the extent of inhibition tends to increase with a rise of salt concentration while the net photosynthesis rate, stomatal conductance, transpiration rate, and internal CO2 concentration are seen to decline with increasing salt concentration. Compared with the control group, the percentage decline is found to be about 48.50, 15.72, 42.09, and 48.33%, respectively. Although all chlorophyll fluorescence of P. euphratica exhibits a typical O-J-I-P curve in differently concentrated salt solutions, salinity stress shows a significant influence on the value of J and I step (P < 0.05). However, salinity stress was seen to induce a decrease in variable fluorescence (Fv)/maximal fluorescence value by 2.32, 8.78, 12.80, 12.93, 16.46, and 19.63% treated by 50-, 100-, 150-, 200-, 250-, and 300-mM salt solution compared with the control group, respectively. Salinity stress appeared also to induce a decrease in Fv/minimal fluorescence values by a magnitude of 5.22, 16.02, 18.06, 22.95, 26.34, and 32.19% in P. euphratica treated by 50-, 100-, 150-, 200-, 250-, and 300-mM salt solution relative to the control group, respectively. An increase in the content of malondialdehyde amounted to 4.12, 25.59, 34.60, 68.11, 70.72, and 67.68% in P. euphratica treated by 50-, 100-, 150-, 200-, 250-, and 300-mM salt solution compared to the control group, respectively. In terms of the content of proline, the salinity stress induced an increase by 4.94, 29.49, 53.20, 77.65, 82.46, and 90.68% in P. euphratica treated by 50-, 100-, 150-, 200-, 250-, and 300-mM salt solution, respectively.


Assuntos
Populus/fisiologia , Salinidade , Estresse Fisiológico/fisiologia , Monitoramento Ambiental , Malondialdeído , Fotossíntese/efeitos dos fármacos , Prolina/metabolismo , Cloreto de Sódio
3.
Zhongguo Zhong Yao Za Zhi ; 39(11): 1972-5, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25272824

RESUMO

Aconitum, as a kind of common traditional Chinese medicine, contains multiple biological active substances, with a very high medicinal value but high toxicity. Its major toxic ingredients are aconitine, mesaconitine and hypaconitine, which are also efficient ingredients. Therefore, the safety of its clinical application has aroused wide attention. With the constant deepening of drug development studies, people want to learn about its toxic mechanism and the regularity of its emergence and development of its toxicology, so as to make a scientific and rational assessment for its safety. Therefore, toxicokinetics and metabonomics have gradually become important content in the new drug assessment. During the development of drug performance, it is crucial to establish a scientific, objective and standardized Aconitum safety evaluation system and correctly assess and utilize its toxicity. Having summarized studies on metabonomics and toxicokinetics of Aconitum drugs in recent years, authors proposed to strengthen the studies on Aconitum drug safety assessment and establish a scientific and standardized safety evaluation system as soon as possible, in order to make the national treasure more useful.


Assuntos
Aconitum/toxicidade , Medicamentos de Ervas Chinesas/farmacocinética , Medicamentos de Ervas Chinesas/toxicidade , Aconitum/química , Animais , Humanos , Metabolômica
4.
Neural Regen Res ; 18(6): 1321-1324, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36453418

RESUMO

In vivo imaging of cerebral ischemia/reperfusion injury remains an important challenge. We injected porous Ag/Au@SiO2 bimetallic hollow nanoshells carrying anti-tropomyosin 4 as a molecular probe into mice with cerebral ischemia/reperfusion injury and observed microvascular changes in the brain using photoacoustic imaging with ultrasonography. At each measured time point, the total photoacoustic signal was significantly higher on the affected side than on the healthy side. Twelve hours after reperfusion, cerebral perfusion on the affected side increased, cerebrovascular injury worsened, and anti-tropomyosin 4 expression increased. Twenty-four hours after reperfusion and later, perfusion on the affected side declined slowly and stabilized after 1 week; brain injury was also alleviated. Histopathological and immunohistochemical examinations confirmed the brain injury tissue changes. The nanoshell molecular probe carrying anti-tropomyosin 4 has potential for use in early diagnosis of cerebral ischemia/reperfusion injury and evaluating its progression.

5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 34(4): 337-42, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22954114

RESUMO

OBJECTIVE: To explore the efficacy of homemade hemostatics of injected gelatin matrix (HIGM) for immediately treating blunt hepatic trauma in canine model without additional pressure. METHODS: A total of 27 commercial hybrid dogs underwent celiotomy to establish hepatic trauma model after general anesthesia. The dogs were prospectively randomized into 3 groups: the treatment group (n=9, with the direct application of homemade hemostat), the positive control group (n=9, with thrombin solution), and the negative control group (n=9, with 0.9% normal saline). Time to hemostasis and intra-abdominal blood loss were recorded, and heart rate (HR), mean arterial pressure (MAP), and hematological parameters were compared among these three groups. Gross examinations were performed 30 minutes after surgery. RESULTS: Significantly shorter time to hemostasis [(1.20±0.33) min] and less blood loss [(47.22±8.61) ml] were observed in the treatment group than in control groups (P 0.05). No cases of bleeding occurred in any animals in the treatment group, and no signs of infection and adhesion formation were evident due to exposure to HIGM. Two cases in the positive control group (22.22%) were found to have rebleeding. All animals in the negative control group experienced visible bleeding. CONCLUSION: HIGM is effective for controlling bleeding after hepatic trauma without the additional compression, and therefore may be valuable in field surgery.


Assuntos
Gelatina/administração & dosagem , Hemostáticos/administração & dosagem , Fígado/lesões , Animais , Modelos Animais de Doenças , Cães , Injeções
6.
J Int Med Res ; 50(10): 3000605221123875, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36262051

RESUMO

OBJECTIVE: This study aimed to describe our experience of managing cesarean scar pregnancy (CSP) and outcomes depending on ultrasound imaging features. METHODS: A retrospective, cohort observational study was performed on 31 consecutive patients with CSP at 6 to 9 weeks of gestation from April 2015 to January 2021. All patients were evaluated for the residual myometrial thickness (RMT), growth direction of the gestational sac (GS), blood flow, and chorionic parenchyma using ultrasonography. Patients underwent curettage or methotrexate (MTX) combined with curettage in CSP depending on the age of the GS. Blood loss of >500 mL with curettage was considered major bleeding. RESULTS: Twenty-five (80.6%) patients had successful treatment, and six (19.4%) patients had major bleeding. The incidence of major bleeding was significantly higher in patients with >7 weeks of gestation, types II and III CSP, mixed and exogenous types of the growth direction of the GS, an RMT < 2 mm, and multiple lacunae formation in thickened chorionic parenchyma. CONCLUSIONS: The exogenous and mixed types of the GS, an RMT < 2 mm, and multiple lacunae in thickened chorionic parenchyma may be high-risk factors for major hemorrhage by curettage in CSP.


Assuntos
Cicatriz , Gravidez Ectópica , Gravidez , Feminino , Humanos , Cicatriz/diagnóstico por imagem , Cicatriz/etiologia , Metotrexato/uso terapêutico , Estudos Retrospectivos , Cesárea/efeitos adversos , Gravidez Ectópica/diagnóstico por imagem , Gravidez Ectópica/etiologia , Gravidez Ectópica/cirurgia , Resultado do Tratamento
7.
Zhong Yao Cai ; 34(12): 1897-9, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22500428

RESUMO

OBJECTIVE: To study the components of volatile oil of Alpinia henryi. METHODS: The volatile oil was extracted by steam distillation method,used gaseous phase-mass spectrum combination method (GC-MS) to analyze the components of volatile oil. RESULTS: 58 kinds of components were isolated, among them 42 were identified and determined the relative content. CONCLUSION: This study provides a basis for the development and utilization of Alpinia henryi.


Assuntos
Alpinia/química , Farneseno Álcool/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/isolamento & purificação , Plantas Medicinais/química , Canfanos , Cicloexanóis/análise , Cicloexanóis/química , Destilação/métodos , Eucaliptol , Farneseno Álcool/química , Frutas/química , Monoterpenos/análise , Monoterpenos/química , Norbornanos/análise , Norbornanos/química , Óleos Voláteis/química , Vapor
8.
Chin Med J (Engl) ; 134(14): 1726-1731, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34238849

RESUMO

BACKGROUND: Reports evaluating the efficacy of transcranial sonography (TCS) for the differential diagnosis of Parkinson disease (PD) and other movement disorders in China are scarce. Therefore, this study aimed to assess the application of TCS for the differential diagnosis of PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and essential tremor (ET) in Chinese individuals. METHODS: From 2017 to 2019, 500 inpatients treated at the Department of Dyskinesia, Beijing Tiantan Hospital, Capital Medical University underwent routine transcranial ultrasound examination. The cross-sections at the midbrain and thalamus levels were scanned, and the incidence rates of substantia nigra (SN) positivity and the incidence rates of lenticular hyperechoic area were recorded. The echo of the SN was manually measured. RESULTS: Of the 500 patients, 125 were excluded due to poor signal in temporal window sound transmission. Among the 375 individuals with good temporal window sound transmission, 200 were diagnosed with PD, 90 with ET, 50 with MSA, and 35 with PSP. The incidence rates of SN positivity differed significantly among the four patient groups (χ2 = 121.061, P < 0.001). Between-group comparisons were performed, and the PD group showed a higher SN positivity rate than the ET (χ2 = 94.898, P < 0.017), MSA (χ2 = 57.619, P < 0.017), and PSP (χ2 = 37.687, P < 0.017) groups. SN positivity showed a good diagnostic value for differentiating PD from the other three movement diseases, collectively or individually. The incidences of lenticular hyperechoic area significantly differed among the four patient groups (χ2 = 38.904, P < 0.001). Next, between-group comparisons were performed. The lenticular hyperechoic area was higher in the PD group than in the ET (χ2 = 6.714, P < 0.017) and MSA (χ2 = 18.680, P < 0.017) groups but lower than that in the PSP group (χ2 = 0.679, P > 0.017). CONCLUSION: SN positivity could effectively differentiate PD from ET, PSP, and MSA in a Chinese population.


Assuntos
Atrofia de Múltiplos Sistemas , Doença de Parkinson , Paralisia Supranuclear Progressiva , Diagnóstico Diferencial , Humanos , Atrofia de Múltiplos Sistemas/diagnóstico por imagem , Doença de Parkinson/diagnóstico por imagem , Substância Negra/diagnóstico por imagem
9.
Chin Med J (Engl) ; 134(4): 415-424, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33617184

RESUMO

BACKGROUND: The current deep learning diagnosis of breast masses is mainly reflected by the diagnosis of benign and malignant lesions. In China, breast masses are divided into four categories according to the treatment method: inflammatory masses, adenosis, benign tumors, and malignant tumors. These categorizations are important for guiding clinical treatment. In this study, we aimed to develop a convolutional neural network (CNN) for classification of these four breast mass types using ultrasound (US) images. METHODS: Taking breast biopsy or pathological examinations as the reference standard, CNNs were used to establish models for the four-way classification of 3623 breast cancer patients from 13 centers. The patients were randomly divided into training and test groups (n = 1810 vs. n = 1813). Separate models were created for two-dimensional (2D) images only, 2D and color Doppler flow imaging (2D-CDFI), and 2D-CDFI and pulsed wave Doppler (2D-CDFI-PW) images. The performance of these three models was compared using sensitivity, specificity, area under receiver operating characteristic curve (AUC), positive (PPV) and negative predictive values (NPV), positive (LR+) and negative likelihood ratios (LR-), and the performance of the 2D model was further compared between masses of different sizes with above statistical indicators, between images from different hospitals with AUC, and with the performance of 37 radiologists. RESULTS: The accuracies of the 2D, 2D-CDFI, and 2D-CDFI-PW models on the test set were 87.9%, 89.2%, and 88.7%, respectively. The AUCs for classification of benign tumors, malignant tumors, inflammatory masses, and adenosis were 0.90, 0.91, 0.90, and 0.89, respectively (95% confidence intervals [CIs], 0.87-0.91, 0.89-0.92, 0.87-0.91, and 0.86-0.90). The 2D-CDFI model showed better accuracy (89.2%) on the test set than the 2D (87.9%) and 2D-CDFI-PW (88.7%) models. The 2D model showed accuracy of 81.7% on breast masses ≤1 cm and 82.3% on breast masses >1 cm; there was a significant difference between the two groups (P < 0.001). The accuracy of the CNN classifications for the test set (89.2%) was significantly higher than that of all the radiologists (30%). CONCLUSIONS: The CNN may have high accuracy for classification of US images of breast masses and perform significantly better than human radiologists. TRIAL REGISTRATION: Chictr.org, ChiCTR1900021375; http://www.chictr.org.cn/showproj.aspx?proj=33139.


Assuntos
Neoplasias da Mama , Aprendizado Profundo , Área Sob a Curva , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , China , Humanos , Curva ROC , Sensibilidade e Especificidade
10.
Oxid Med Cell Longev ; 2020: 7963212, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33123316

RESUMO

Triple-negative breast cancers (TNBCs) are associated with poor patient survival because of the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) expressions. Our previous studies have shown that the triterpenoid saponin AG8 from Ardisia gigantifolia stapf. inhibits the proliferation of MDA-MB-231 cells. In this study, the effects of AG8 were further analyzed in different TNBC cell types: MDA-MB-231, BT-549, and MDA-MB-157 cells. AG8 inhibited the viability of MDA-MB-231, BT-549, and MDA-MB-157 cells in a dose-dependent manner and showed stronger cytotoxicity to African American (AA) and mesenchymal (M) subtypes than Caucasian (CA) and mesenchymal stem-like (MSL) subtypes, respectively. AG8 impaired the uptake of MitoTracker Red CMXRos by the mitochondria of TNBC cells in a dose-dependent manner, and this was recovered by N-acetyl-l-cysteine (NAC). AG8 affected GSH, SOD, and MDA levels of TNBC cells, but different TNBC subtypes had different sensitivities to AG8 and NAC. In addition, we found that AG8 increased the Bax/Bcl-2 ratio and the levels of cytoplasmic cytochrome c and significantly decreased phosphorylation of ERK and AKT in BT549 and MDA-MB-157 cells. AG8 elicited its anticancer effects through ROS generation, ERK and AKT activation, and by triggering mitochondrial apoptotic pathways in TNBC cells. AG8 had selective cytotoxic effects against the AA and M TNBC subtypes and markedly induced MDA-MB-157 (AA subtype) cell apoptosis through pathways that were not associated with ROS, which was different from the other two subtypes. The underlying mechanisms should be further investigated.


Assuntos
Apoptose/efeitos dos fármacos , Ardisia/química , Estresse Oxidativo/efeitos dos fármacos , Saponinas/farmacologia , Acetilcisteína/farmacologia , Ardisia/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Glutationa/metabolismo , Humanos , Malondialdeído/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína Oncogênica v-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Triterpenos/farmacologia , Proteína X Associada a bcl-2/metabolismo
11.
Zhongguo Zhong Yao Za Zhi ; 30(14): 1096-8, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16161447

RESUMO

OBJECTIVE: To compare the actions of the three flavone ingredients in choerospondias axillaris on arrhythmias Induced by aconitine. METHOD: Langendorff perfuse was applied in the experiment, the antiarrhythmic action was to study by using aconitine on the the isolated heart; The antiarrhythmic action of the three flavone ingredients in choerospondias axillaris was to study by using i.v. aconitine in rat to induce arrhythmias. RESULT: Compared with the NS group, sample 1 and sample 2 both significantly prolonged the beginning time of VF of isolated heart and increased the dosage of aconitine, sample 3 reduced the beginning time of VF of isolated heart and decreased the dosage of aconitine, sample 1 and sample 2 both greatly prolonged the beginning time of VE, VT, VF, HA; sample 3 greatly reduced the beginning time of VT,VF. The actions of the three samples were in a concentration-dependent way. CONCLUSION: Sample 1 and sample 2 both resisted the occurrence of arrhythmias induced by aconitine, sample 3 markedly promoted the occurrence of arrhythmias induced by aconitine.


Assuntos
Anacardiaceae , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/prevenção & controle , Flavonas/uso terapêutico , Fitoterapia , Aconitina , Anacardiaceae/química , Animais , Antiarrítmicos/isolamento & purificação , Arritmias Cardíacas/induzido quimicamente , Relação Dose-Resposta a Droga , Feminino , Flavonas/isolamento & purificação , Técnicas In Vitro , Masculino , Plantas Medicinais/química , Distribuição Aleatória , Ratos , Ratos Wistar
12.
Ying Yong Sheng Tai Xue Bao ; 25(1): 211-8, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24765863

RESUMO

In the arid inland area of Northwest China, the ecological water transfer and rehabilitation project (EWTRP) is an important measure to restore the deteriorated ecosystem. However, the sustainability of the project is affected by many socio-economic factors. This research was based on results of the questionnaire from Ejina County's farmer households, which included the farmer households' attitude, livelihood and the efficiency of the water resource usage. The results showed that although the EWTRP had made great achievements in vegetation restoration, but the sustainability of the project was affected by the following factors: the ecologically-motivated relocated/resettled herdsmen mainly relied on the compensation from the project, causing them a hard living, and increasing the risk of maintaining the current achievement; the project didn't have a positive impact on water-saving agriculture, the efficiency of water usage was relatively low and had not yet reached the final goal; the compensation of the project only considered the loss of agriculture, but neglected the externality and publicity of eco-water. We suggest that developing education, offering job opportunity and training programs, improving the efficiency of water usage and establishing reasonable water resources compensation mechanisms are needed to be considered as main domain of environmental recovery as well as ecological water transfer and rehabilitation.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Água , China , Coleta de Dados , Ecossistema , Inquéritos e Questionários
13.
Chin Med J (Engl) ; 124(9): 1352-6, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21740747

RESUMO

BACKGROUND: The non-operation treatment of intra-abdominal trauma guided contrast enhanced ultrasound (CEUS) is one of the hottest research topic. Gelatin/thrombin/calcium (GTC) was developed as a novel haemostatic agent for non-operable intra-abdominal trauma. We hypothesized that GTC can achieve haemostasis (without the use of pressure) within a short time in a large wound model by percutaneous injection under CEUS guidance. METHODS: Forty Wister rats received large liver injuries by haemostatic clamp and were randomly divided into four groups, according to the haemostatic agent used. These included normal saline (NS) group A, lyophilising thrombin powder (LTP) group B, GTC group C, and absorbable α-cyanoacrylate (ACNA) group D. Each injury site was treated with one of the above materials and total bleeding time was recorded. All liver wounds were evaluated using CEUS at three periods: pre-injury, injury and post-treatment. The liver wounds were also evaluated by histology 3, 6, and 9 days after injury and the extents of abdominal adhesions were recorded. RESULTS: The sensitivity of CEUS (100%) in detecting blunt traumatic liver lesions was significantly higher than conventional ultrasound (42.5%). Bleeding times at the injury site in the GTC group C ((129.3 ± 14.0) seconds) and ACNA group D ((5.2 ± 1.0) seconds) were significantly shorter than those in the NS group A ((369.5 ± 48.8) seconds, P < 0.01) and LTP group B ((324.7 ± 52.22) seconds, P < 0.01). The LTP group B showed no significant difference compared with the NS group A. Gross examination of liver tissue revealed that there were fewer intra-abdominal adhesions in the GTC group C (10%) than in the ACNA group D (100%). Histopathologic examination showed that GTC was completely absorbed after nine days. CONCLUSIONS: GTC, delivered by percutaneous injection under CEUS, may achieve haemostasis (without the use of pressure) within a short time in a large wound model. GTC is absorbable and may prevent intra-abdominal adhesions. Therefore, it may be the optimal choice for first aid treatment of large abdominal wounds in the setting of blunt trauma.


Assuntos
Cálcio/uso terapêutico , Gelatina/uso terapêutico , Hemostáticos/uso terapêutico , Fígado/diagnóstico por imagem , Fígado/lesões , Trombina/uso terapêutico , Animais , Cálcio/administração & dosagem , Gelatina/administração & dosagem , Hemorragia/diagnóstico por imagem , Hemorragia/tratamento farmacológico , Hemostáticos/administração & dosagem , Injeções , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Trombina/administração & dosagem , Ultrassonografia
14.
Ying Yong Sheng Tai Xue Bao ; 22(8): 1961-6, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-22097354

RESUMO

By the method of geostatistics, this paper studied the spatial heterogeneity of plant community species diversity in Ejina Oasis at the lower reaches of Heihe River. In the study area, the Margalef richness index (Ma), Simpson diversity index (Ds), Shannon diversity index (H') and Pielou evenness index (J') were in normal distribution, and the coefficient of variation (CV) ranged from 55.8% to 67.8%, suggesting a moderate variability. The Ma and H' were accorded with exponential models, and the Ds and J' were accorded with spherical models. The H' had the highest extent of spatial variation, followed by Ma, J' and Ds. Within the variable range, the structural factors in the spatial variation of Ma, Ds, H', and J' were dominant, ranging from 81.1% to 93.0%. The indices changed obviously parallel to the river, with significantly high values near Dalaihubu Town (42 degrees N, 101 degrees E), and obviously low values within the strips 100 degrees-101 degrees E and 102 degrees-102 degrees 30' E, mainly including east and west Gobi and the hinterland of Badain Jaran Desert.


Assuntos
Biodiversidade , Ecossistema , Desenvolvimento Vegetal , China , Conservação dos Recursos Naturais , Clima Desértico , Plantas/classificação , Dinâmica Populacional , Populus/crescimento & desenvolvimento , Rios , Tamaricaceae/crescimento & desenvolvimento
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