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1.
Cardamonin (CD), a naturally occurring chalcone isolated from large black cardamom, was previously reported to suppress the proliferation of breast cancer cells. However, its precise molecular anti‐tumor mechanisms have not been well elucidated. In this study, we found that CD markedly inhibited the proliferation of MDA‐MB 231 and MCF‐7 breast cancer cells through the induction of G2/M arrest and apoptosis. Reactive oxygen species (ROS) plays a pivotal role in the inhibition of CD‐induced cell proliferation. Treatment with N‐acetyl‐cysteine (NAC), an ROS scavenger, blocked CD‐induced G2/M arrest and apoptosis in this study. Quenching of ROS by overexpression of catalase also blocked CD‐induced cell cycle arrest and apoptosis. We showed that CD enhanced the expression and nuclear translocation of Forkhead box O3 (FOXO3a) via upstream c‐Jun N‐terminal kinase, inducing the expression of FOXO3a and its target genes, including p21, p27, and Bim. This process led to the reduction of cyclin D1 and enhancement of activated caspase‐3 expression. The addition of NAC markedly reversed these effects, knockdown of FOXO3a using small interfering RNA also decreased CD‐induced G2/M arrest and apoptosis. In vivo, CD efficiently suppressed the growth of MDA‐MB 231 breast cancer xenograft tumors. Taken together, our data provide a molecular mechanistic rationale for CD‐induced cell cycle arrest and apoptosis in breast cancer cells.  相似文献   
2.
Studying the pattern of species richness is crucial in understanding the diversity and distribution of organisms in the earth. Climate and human influences are the major driving factors that directly influence the large‐scale distributions of plant species, including gymnosperms. Understanding how gymnosperms respond to climate, topography, and human‐induced changes is useful in predicting the impacts of global change. Here, we attempt to evaluate how climatic and human‐induced processes could affect the spatial richness patterns of gymnosperms in China. Initially, we divided a map of the country into grid cells of 50 × 50 km2 spatial resolution and plotted the geographical coordinate distribution occurrence of 236 native gymnosperm taxa. The gymnosperm taxa were separated into three response variables: (a) all species, (b) endemic species, and (c) nonendemic species, based on their distribution. The species richness patterns of these response variables to four predictor sets were also evaluated: (a) energy–water, (b) climatic seasonality, (c) habitat heterogeneity, and (d) human influences. We performed generalized linear models (GLMs) and variation partitioning analyses to determine the effect of predictors on spatial richness patterns. The results showed that the distribution pattern of species richness was highest in the southwestern mountainous area and Taiwan in China. We found a significant relationship between the predictor variable set and species richness pattern. Further, our findings provide evidence that climatic seasonality is the most important factor in explaining distinct fractions of variations in the species richness patterns of all studied response variables. Moreover, it was found that energy–water was the best predictor set to determine the richness pattern of all species and endemic species, while habitat heterogeneity has a better influence on nonendemic species. Therefore, we conclude that with the current climate fluctuations as a result of climate change and increasing human activities, gymnosperms might face a high risk of extinction.  相似文献   
3.
利用固体淀粉筛选培养基,从安阳市郊区面粉厂附近的土壤里分离筛选出1株产淀粉酶的菌株,编号为MF-3-2.经过菌株形态、革兰氏染色、16S rDNA鉴定及系统进化树分析,初步确定其为枯草芽孢杆菌(Bacillus subtilis).摇瓶培养后对其酶学性质研究发现,该菌株淀粉酶的最适温度为65℃,最适pH值为6.0,在pH值4.8~6.0范围内仍能残余70%以上的酶活力.该菌株的最适生长温度为40℃,最适生长pH值为6.5.产酶条件优化结果表明:最适碳源为马铃薯淀粉,最适氮源为豆粕粉,最适碳氮比为1∶15,发酵温度30℃,发酵pH值6.0,装液量10%,种龄10h,接种量5%,转速200 r/min,48 h达到产酶高峰.通过发酵产酶条件优化,其淀粉酶活性达到86.8 U/mL,是优化前的35倍.另外,在酸性条件下还具有较好的活性.因此,该菌株的淀粉酶具有潜在的工业应用前景.  相似文献   
4.

Background

With the establishment of minimally invasive surgery in society, the robot has been increasingly widely used in the urologic field, including in partial nephrectomy. This study aimed to comprehensively summarize the currently available evidence on the feasibility and safety of robotic partial nephrectomy for renal tumors of >4 cm.

Method and Findings

An electronic database search of PubMed, Scopus, Web of Science, and the Cochrane Library was performed. This systematic review and meta-analysis was based on all relevant studies that assessed robotic partial nephrectomy for renal tumors of >4 cm. Five studies were included. The meta-analysis involved 3 studies from 11 institutions including 154 patients, while the narrative review involved the remaining 2 studies from 5 institutions including 64 patients. In the meta-analysis, the mean ischemic time, operation time, and console time was 28, 319, and 189 minutes, respectively. The estimated blood loss and length of stay was 317 ml and 3.8 days, respectively. The rates of conversion, positive margins, intraoperative complications, postoperative complications, hilar clamping, and collecting system repair were 7.0%, 3.5%, 7.0%, 9.8%, 93.9%, and 47.5%, respectively. The narrative review showed results similar to those of the meta-analysis.

Conclusions

Robotic partial nephrectomy is feasible and safe for renal tumors of >4 cm with an acceptable warm ischemic time, positive margin rate, conversion rate, complication rate, operation time, estimated blood loss, and length of stay.  相似文献   
5.

Background

Leishmaniasis and malaria are the two most common parasitic diseases and responsible for large number of deaths per year particularly in developing countries like Pakistan. Majority of Pakistan population rely on medicinal plants due to their low socio-economic status. The present review was designed to gather utmost fragmented published data on traditionally used medicinal plants against leishmaniasis and malaria in Pakistan and their scientific validation.

Methods

Pub Med, Google Scholar, Web of Science, ISI Web of knowledge and Flora of Pakistan were searched for the collection of data on ethnomedicinal plants. Total 89 articles were reviewed for present study which was mostly published in English. We selected only those articles in which complete information was given regarding traditional uses of medicinal plants in Pakistan.

Results

Total of 56 plants (malaria 33, leishmaniasis 23) was found to be used traditionally against reported parasites. Leaves were the most focused plant part both in traditional use and in in vitro screening against both parasites. Most extensively used plant families against Leishmaniasis and Malaria were Lamiaceae and Asteraceae respectively. Out of 56 documented plants only 15 plants (Plasmodia 4, Leishmania 11) were assessed in vitro against these parasites. Mostly crude and ethanolic plant extracts were checked against Leishmania and Plasmodia respectively and showed good inhibition zone. Four pure compounds like artemisinin, physalins and sitosterol extracted from different plants proved their efficacy against these parasites.

Conclusions

Present review provides the efficacy and reliability of ethnomedicinal practices and also invites the attention of chemists, pharmacologist and pharmacist to scientifically validate unexplored plants that could lead toward the development of novel anti-malarial and anti-leishmanial drugs.
  相似文献   
6.
Eucalyptus grandis is the most widely planted tree species worldwide and can face severe drought during the initial months after planting because the root system is developing. A complete randomized design was used to study the effects of two water regimes (well‐watered and water‐stressed) and phosphorus (P) applications (with and without P) on the morphological and physio‐biochemical responses of E. grandis. Drought had negative effects on the growth and metabolism of E. grandis, as indicated by changes in morphological traits, decreased net photosynthetic rates (Pn), pigment concentrations, leaf relative water contents (LRWCs), nitrogenous compounds, over‐production of reactive oxygen species (ROS) and higher lipid peroxidation. However, E. grandis showed effective drought tolerance strategies, such as reduced leaf area and transpiration rate (E), higher accumulation of soluble sugars and proline and a strong antioxidative enzyme system. P fertilization had positive effects on well‐watered seedlings due to improved growth and photosynthesis, which indicated the high P requirements during the initial E. grandis growth stage. In drought‐stressed seedlings, P application had no effects on the morphological traits, but it significantly improved the LRWC, Pn, quantum efficiency of photosystem II (Fv/Fm), chlorophyll pigments, nitrogenous compounds and reduced lipid peroxidation. P fertilization improved E. grandis seedling growth under well‐watered conditions but also ameliorated some leaf physiological traits under drought conditions. The effects of P fertilization are mainly due to the enhancement of plant N nutrition. Therefore, P can be used as a fertilizer to improve growth and production in the face of future climate change.  相似文献   
7.
桂西南喀斯特地区是广西也是中国生物多样性保护优先区域。基于该地区关键区域的深入调查,该文报道了广西被子植物新记录20种,即木姜叶征镒木[Wuodendron praecox(Hook. f.&Thomson) B. Xue, Y. H. Tan&X. L. Hou]、大果楠(Phoebe macrocarpa C. Y. Wu)、国楣铁线莲(Clematis fengii W. T. Wang)、方籽栝楼(Trichosanthes tetragonosperma C. Y. Cheng&Yueh)、枥叶花楸(Sorbus yunnanensis L. T. Lu)、长苞楼梯草(Elatostema longibracteatum W. T. Wang)、富宁槭(Acer paihengii Fang)、云南山茱萸(Cornus eydeana Q. Y. Xiang&Y. M. Shui)、长梗杜鹃(Rhododendron longipedicellatum Lei Cai&Y. P. Ma)、粉花安息香(Styrax roseus Dunn...  相似文献   
8.
Adipose tissue inflammation in obesity is a major factor leading to cardiovascular disease and type 2 diabetes.12/15 lipoxygenases (ALOX) play an important role in the generation of inflammatory mediators, insulin resistance and downstream immune activation in animal models of obesity. However, the expression and roles of 12/15ALOX isoforms, and their cellular sources in human subcutaneous (sc) and omental (om) fat in obesity is unknown. The objective of this study was to examine the gene expression and localization of ALOX isoforms and relevant downstream cytokines in subcutaneous (sc) and omental (om) adipose tissue in obese humans. Paired biopsies of sc and om fat were obtained during bariatric surgeries from 24 morbidly obese patients. Gene and protein expression for ALOX15a, ALOX15b and ALOX 12 were measured by real-time PCR and western blotting in adipocytes and stromal vascular fractions (SVF) from om and sc adipose tissue along with the mRNA expression of the downstream cytokines IL-12a, IL-12b, IL-6, IFNγ and the chemokine CXCL10. In a paired analysis, all ALOX isoforms, IL-6, IL-12a and CXCL10 were significantly higher in om vs. sc fat. ALOX15a mRNA and protein expression was found exclusively in om fat. All of the ALOX isoforms were expressed solely in the SVF. Further fractionation of the SVF in CD34+ and CD34- cells indicated that ALOX15a is predominantly expressed in the CD34+ fraction including vascular and progenitor cells, while ALOX15B is mostly expressed in the CD34- cells containing various leucocytes and myeloid cells. This result was confirmed by immunohistochemistry showing exclusive localization of ALOX15a in the om fat and predominantly in the vasculature and non-adipocyte cells. Our finding is identifying selective expression of ALOX15a in human om but not sc fat. This is a study showing a major inflammatory gene exclusively expressed in visceral fat in humans.  相似文献   
9.
The relationships between floral morphology and the particular pollinator, flower shelter function and reproductive success as well as details of the breeding system of Dendrobium jiajiangense were investigated at Fotang Mountains in Jiajiang County, Sichuan Province, China. D. jiajiangense is pollinator-specific, being pollinated by Andrena parvula. There exists considerable mechanical fit between the floral morphology of D. jiajiangense and A. parvula. Importantly, A. parvula uses D. jiajiangense flowers as shelter both during rainy weather and at night during sunny weather. This significantly increase the pollination success of D. jiajiangens. D. jiajiangense is self-compatible but pollinator-dependent for fruit set. Fruit set of D. jiajiangens was 100% after hand-self-pollination, but seed viability was normally greatly reduced.  相似文献   
10.
岷江上游暗针叶林采伐迹地人工混交林群落结构   总被引:5,自引:1,他引:4  
对四川岷江上游高山峡谷区暗针叶林采伐迹地年龄为20-40年的人工混交林群落结构进行了研究,结果是:(1)群落中各层次物种盖度的大小相互影响,相互制约,而林下(各)层次物种盖度的大小主要取决于其上(各)层盖度(或郁闭度)的大小,(2)人工重建的群落所能容纳的物种数及物种在群落中的分布状况主要取决于乔木物种郁工,海拔高度及经营强度。(3)群落中出现大量的耐荫植物,先锋灌丛植物已被抑制或淘汰,(4)乔木  相似文献   
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