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91.
From the bark of Zizyphus sativa, in addition to already described cyclopeptide alkaloids, two new compounds of this class, sativanine-A(1) and sativanine-B(2), were isolated. Both alkaloids contain 14-membered ring systems. 1 belongs to the integerrine type, while 2 is similar to nummularine-G, with an additional ring in the side chain. 相似文献
92.
Georgia Vasileiou Silvia Vergarajauregui Sabine Endele Bernt Popp Christian Büttner Arif B. Ekici Marion Gerard Nuria C. Bramswig Beate Albrecht Jill Clayton-Smith Jenny Morton Susan Tomkins Karen Low Astrid Weber Maren Wenzel Janine Altmüller Yun Li Bernd Wollnik André Reis 《American journal of human genetics》2018,102(3):468-479
93.
94.
Gayoor Ali A. Arif Ibrahim Prem Shankar Srivastava Muhammad Iqbal 《Journal of Plant Biology》1999,42(3):222-225
Various concentrations of salt (NaCI) were shown to have an influence on the differentiation of tissues in the root and stem
ofBacopa monniera (L) Wettst. Higher concentrations induced drastic changes in roots grown on salt-supplemented media; epidermal and cortical
cells experienced changes in shape, size, and orientation and/or were got disintegrated. A low concentration of salt induced
a profuse development of root hairs which gradually disappeared at higher concentrations. Air spaces in the stem cortex were
enlarged and xylem cell walls in the vascular ring were thickened. 相似文献
95.
Has the rising placebo response impacted antidepressant clinical trial outcome? Data from the US Food and Drug Administration 1987‐2013 下载免费PDF全文
Arif Khan Kaysee Fahl Mar Jim Faucett Shirin Khan Schilling Walter A. Brown 《World psychiatry》2017,16(2):181-192
More than fifteen years ago, it was noted that the failure rate of antidepressant clinical trials was high, and such negative outcomes were thought to be related to the increasing magnitude of placebo response. However, there is considerable debate regarding this phenomenon and its relationship to outcomes in more recent antidepressant clinical trials. To investigate this, we accessed the US Food and Drug Administration (FDA) reviews for sixteen antidepressants (85 trials, 115 trial arms, 23,109 patients) approved between 1987 and 2013. We calculated the magnitude of placebo and antidepressant responses, antidepressant‐placebo differences, as well as the effect sizes and success rates, and compared these measures over time. Exploratory analysis investigated potential changes in trial design and conduct over time. As expected, the magnitude of placebo response has steadily grown in the past 30 years, increasing since 2000 by 6.4% (r=0.46, p<0.001). Contrary to expectations, a similar increase has occurred in the magnitude of antidepressant response (6.0%, r=0.37, p<0.001). Thus, the effect sizes (0.30 vs. 0.29, p=0.42) and the magnitude of antidepressant‐placebo differences (10.5% vs. 10.3%, p=0.37) have remained statistically equivalent. Furthermore, the frequency of positive trial arms has gone up in the past 15 years (from 47.8% to 63.8%), but this difference in frequency has not reached statistical significance. Trial design features that were previously associated with a possible lower magnitude of placebo response were not implemented, and their relationship to the magnitude of placebo response could not be replicated. Of the 34 recent trials, two implemented enhanced interview techniques, but both of them were unsuccessful. The results of this study suggest that the relationship between the magnitude of placebo response and the outcome of antidepressant clinical trials is weak at best. These data further indicate that antidepressant‐placebo differences are about the same for all of the sixteen antidepressants approved by the FDA in the past thirty years. 相似文献
96.
97.
Tropical soils degraded by slash‐and‐burn cultivation can be recultivated when amended with ashes and compost 下载免费PDF全文
Justine Marie Gay‐des‐Combes Clara Sanz Carrillo Bjorn Jozef Maria Robroek Vincent Eric Jules Jassey Robert Thomas Edmund Mills Muhammad Saleem Arif Leia Falquet Emmanuel Frossard Alexandre Buttler 《Ecology and evolution》2017,7(14):5378-5388
In many tropical regions, slash‐and‐burn agriculture is considered as a driver of deforestation; the forest is converted into agricultural land by cutting and burning the trees. However, the fields are abandoned after few years because of yield decrease and weed invasion. Consequently, new surfaces are regularly cleared from the primary forest. We propose a reclamation strategy for abandoned fields allowing and sustaining re‐cultivation. In the dry region of south‐western Madagascar, we tested, according to a split‐plot design, an alternative selective slash‐and‐burn cultivation technique coupled with compost amendment on 30–year‐old abandoned fields. Corn plants (Zea mays L.) were grown on four different types of soil amendments: no amendment (control), compost, ashes (as in traditional slash‐and‐burn cultivation), and compost + ashes additions. Furthermore, two tree cover treatments were applied: 0% tree cover (as in traditional slash‐and‐burn cultivation) and 50% tree cover (selective slash‐and‐burn). Both corn growth and soil fertility parameters were monitored during the growing season 2015 up to final harvest. The amendment compost + ashes strongly increased corn yield, which was multiplied by 4–5 in comparison with ashes or compost alone, reaching 1.5 t/ha compared to 0.25 and 0.35 t/ha for ashes and compost, respectively. On control plots, yield was negligible as expected on these degraded soils. Structural equation modeling evidenced that compost and ashes were complementary fertilizing pathways promoting soil fertility through positive effects on soil moisture, pH, organic matter, and microbial activity. Concerning the tree cover treatment, yield was reduced on shaded plots (50% tree cover) compared to sunny plots (0% tree cover) for all soil amendments, except ashes. To conclude, our results provide empirical evidence on the potential of recultivating tropical degraded soils with compost and ashes. This would help mitigating deforestation of the primary forest by increasing lifespan of agricultural lands. 相似文献
98.
Naqvi RA Hussain A Raish M Noor A Shahid M Sarin R Kukreti H Khan NJ Ahmad S Deo SV Husain SA Pasha ST Basir SF Shukla NK 《DNA and cell biology》2008,27(9):517-525
Even after tremendous molecular studies, early detection,more accurate and sensitive diagnosis, and prognosis of breast cancer appear to be a riddle so far. To stab the enigma, this study is designed to envisage DNA methylation signatures as cancer-specific and stage-specific biomarkers in Indian patients. Rigorous review of scattered scientific reports on aberrant DNA methylation helped us to select and analyze a potential tumor suppressor gene pair (FHIT and p16 genes) in breast cancer patients. Methylation signatures from 232 primary sporadic breast cancer patients were pinpointed by methylation-specific PCR (MSP). To increase the sensitivity, we combined both MSP and expression studies (RT-PCR and Northern blotting) in a reproducible manner. Statistical analysis illustrated that hypermethylation of FHIT gene ( p < 0.0001) and p16 gene ( p=0.04) may be used as a potential diagnostic marker to diagnose the early and locally advanced stages of breast cancer. Additionally, the study authenticates the dependency of methylation and expressional loss of p16 gene on FHIT gene silencing. This observation not only describes the severity of disease when both genes are silenced but also drives to speculate the molecular cross talk between two genes or genetic pathways dictated by them separately. 相似文献
99.
Arif U Hasan Setsuo Suguri Chigusa Fujimoto Rodney L Itaki Masakazu Harada Masato Kawabata Hugo Bugoro Bobogare Albino 《BMC evolutionary biology》2008,8(1):318
Background
The mosquito Anopheles irenicus, a member of the Anopheles punctulatus group, is geographically restricted to Guadalcanal in the Solomon Islands. It shows remarkable morphological similarities to one of its sibling species, An. farauti sensu stricto (An. farauti s.s.), but is dissimilar in host and habitat preferences. To infer the genetic variations between these two species, we have analyzed mitochondrial cytochrome oxidase subunit II (COII) and nuclear ribosomal internal transcribed spacer 2 (ITS2) sequences from Guadalcanal and from one of its nearest neighbours, Malaita, in the Solomon Islands. 相似文献100.
The roles of MAPKs in disease 总被引:2,自引:0,他引:2
Lawrence MC Jivan A Shao C Duan L Goad D Zaganjor E Osborne J McGlynn K Stippec S Earnest S Chen W Cobb MH 《Cell research》2008,18(4):436-442