全文获取类型
收费全文 | 123篇 |
免费 | 9篇 |
国内免费 | 1篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 5篇 |
2014年 | 6篇 |
2013年 | 12篇 |
2012年 | 12篇 |
2011年 | 14篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 10篇 |
2007年 | 7篇 |
2006年 | 7篇 |
2005年 | 3篇 |
2004年 | 2篇 |
2003年 | 2篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1981年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有133条查询结果,搜索用时 15 毫秒
21.
22.
Cheon Y Park JY Modi HR Kim HW Lee HJ Chang L Rao JS Rapoport SI 《Journal of neurochemistry》2011,119(2):364-376
The atypical antipsychotic, olanzapine (OLZ), is used to treat bipolar disorder, but its therapeutic mechanism of action is not clear. Arachidonic acid (AA, 20:4n-6) plays a critical role in brain signaling and an up-regulated AA metabolic cascade was reported in postmortem brains from bipolar disorder patients. In this study, we tested whether, similar to the action of the mood stabilizers lithium, carbamazepine and valproate, chronic OLZ treatment would reduce AA turnover in rat brain. We administered OLZ (6 mg/kg/day) or vehicle i.p. to male rats once daily for 21 days. A washout group received 21 days of OLZ followed by vehicle on day 22. Two hours after the last injection, [1-1?C]AA was infused intravenously for 5 min, and timed arterial blood samples were taken. After the rat was killed at 5 min, its brain was microwaved, removed and analyzed. Chronic OLZ decreased plasma unesterified AA concentration, AA incorporation rates and AA turnover in brain phospholipids. These effects were absent after washout. Consistent with reduced AA turnover, OLZ decreased brain cyclooxygenase activity and the brain concentration of the proinflammatory AA-derived metabolite, prostaglandin E?, In view of up-regulated brain AA metabolic markers in bipolar disorder, the abilities of OLZ and the mood stabilizers to commonly decrease prostaglandin E?, and AA turnover in rat brain phospholipids, albeit by different mechanisms, may be related to their efficacy against the disease. 相似文献
23.
Vasken L. Keleshian Matthew Kellom Hyung-Wook Kim Ameer Y. Taha Yewon Cheon Miki Igarashi Stanley I. Rapoport Jagadeesh S. Rao 《PloS one》2014,9(5)
Background
Dietary long-chain n-3 polyunsaturated fatty acid (PUFA) supplementation may be beneficial for chronic brain illnesses, but the issue is not agreed on. We examined effects of dietary n-3 PUFA deprivation or supplementation, compared with an n-3 PUFA adequate diet (containing alpha-linolenic acid [18:3 n-3] but not docosahexaenoic acid [DHA, 22:6n-3]), on brain markers of lipid metabolism and excitotoxicity, in rats treated chronically with NMDA or saline.Methods
Male rats after weaning were maintained on one of three diets for 15 weeks. After 12 weeks, each diet group was injected i.p. daily with saline (1 ml/kg) or a subconvulsive dose of NMDA (25 mg/kg) for 3 additional weeks. Then, brain fatty acid concentrations and various markers of excitotoxicity and fatty acid metabolism were measured.Results
Compared to the diet-adequate group, brain DHA concentration was reduced, while n-6 docosapentaenoic acid (DPA, 22:5n-6) concentration was increased in the n-3 deficient group; arachidonic acid (AA, 20:4n-6) concentration was unchanged. These concentrations were unaffected by fish oil supplementation. Chronic NMDA increased brain cPLA2 activity in each of the three groups, but n-3 PUFA deprivation or fish oil did not change cPLA2 activity or protein compared with the adequate group. sPLA2 expression was unchanged in the three conditions, whereas iPLA2 expression was reduced by deprivation but not changed by supplementation. BDNF protein was reduced by NMDA in N-3 PUFA deficient rats, but protein levels of IL-1β, NGF, and GFAP did not differ between groups.Conclusions
N-3 PUFA deprivation significantly worsened several pathological NMDA-induced changes produced in diet adequate rats, whereas n-3 PUFA supplementation did not affect NMDA induced changes. Supplementation may not be critical for this measured neuropathology once the diet has an adequate n-3 PUFA content. 相似文献24.
Mavinahalli N. Jagadeesh Anindita Makur Jayaraman Chandrasekhar 《Journal of molecular modeling》2000,6(2):226-233
The belt-like polyphenylenes, [0n]paracyclophanes, (n = 5 and 6), have been investigated using semi-empirical, ab initio and DFT methods. The molecular structure, rotational barrier on twisting a single phenyl ring and the aromatic character within each ring as well as in the whole molecule have been evaluated. [05]Paracyclophane is predicted to have a quinonoid structure. In contrast, the equatorial pentaphenyl fragment found in C70 as well as the hexagons of the less strained [06]paracyclophane have benzenoid character. Approximate band structures have been derived for larger cycles of [0n] paracyclophanes.Electronic Supplementary Material available. 相似文献
25.
Chronic Administration of Mood Stabilizers Upregulates BDNF and Bcl-2 Expression Levels in Rat Frontal Cortex 总被引:1,自引:0,他引:1
Brain-derived neurotrophic factor (BDNF) and B-cell lymphoma-2 (Bcl-2) proteins are neuroprotective factors involved in neuronal
signaling, survival and plasticity. Both can be regulated by cyclic AMP response element binding (CREB) protein. Decreased
levels of BDNF and Bcl-2 are implicated in the pathogenesis of bipolar disorder. The present study investigated whether chronically
administered mood stabilizers would increase BDNF and/or Bcl-2 levels in rat brain. Real time RT-PCR, sandwich ELISA and Western
blotting were used to measure BDNF and Bcl-2 mRNA and protein levels in the frontal cortex of rats chronically administered
carbamazepine (CBZ) or lamotrigine (LTG) to produce plasma concentrations therapeutically relevant to bipolar disorder. Chronic
CBZ and LTG significantly increased BDNF and Bcl-2 mRNA and protein levels in the frontal cortex. A common mechanism of action
of mood stabilizers in the treatment of bipolar disorder may involve neuroprotection mediated by upregulation of brain BDNF
and Bcl-2 expression. 相似文献
26.
Microbial decolorization of spentwash: a review 总被引:1,自引:0,他引:1
Spentwash is one of the most complex and cumbersome wastewater with very high BOD, COD and other organic and inorganic toxic
constituents. It is dark brown colored and difficult to treat by normal biological process such as activated sludge or anaerobic
lagooning. The color is due to the presence of melanoidins, caramels and other polymers. These compounds have anti oxidant
properties which render them toxic to microorganisms. Spentwash disposal into the environment is hazardous and has a considerable
pollution potential. It affects the aesthetic merit. Its decolorization by physical or chemical methods have been investigated
and were found unsuitable. In the recent past, increasing attention has been directed towards utilizing microbial activity
for decolorization of spentwash. This review reveals various groups of microorganisms which have potential in spentwash decolorization.
The role of enzymes in decolorization and the microbial degradation of individual compounds imparting color to spentwash are
also discussed. 相似文献
27.
Summary Cholinergic inhibition of myocardial adenylate cyclase activity in cell-free fractions has been known for many years, although the reported degrees of inhibition have been rather modest (20–30%), notably in rat heart fractions. The present study conducted with rat heart subcellular fractions document following major findings: (1) Myocardial adenylate cyclase activity and notably its cholinergic inhibition in cell-free fractions are notoriously labile to storage at 4°C whereas its stimulation by beta adrenergic receptor agonists or forskolin are reasonably well preserved during storage. (2) Among four buffers (Tris, glycylglycine, imidazole and sodium phosphate) examined, sodium phosphate buffer afforded the best preservation of cholinergic inhibitory response of adenylate cyclase. (3) The commonly used biochemical buffers, notably imidazole, exerted deleterious effect on the cholinergic inhibition of myocardial adenylate cyclase such that it was considerably attenuated or barely detectable; this explains, in part, the reported poor inhibition of myocardial enzyme by others. (4) Imidazole buffer, on the other hand, augmented beta adrenergic and forskolin stimulated adenylate cyclase activity. The likely significance of these findings is discussed from consideration that the observed differential influence of buffers results from differential actions on the interactions between the components (receptor/coupling G proteins/catalyst) comprising autonomic receptor coupled adenylate cyclase system in rat heart. 相似文献
28.
Clarias batrachus (Linn) and Channa punctatus (Bloch) were exposed to 5, 10 and 15 ppm of vanadium and investigated the effects on tissue glycogen at 3, 6 and 9 hrs. Results indicated the variations in the level of glycogen were highest at 15 ppm after 9 hr exposure in liver than muscle, brain, kidney and heart of Clarias batrachus as compared to Channa punctatus. The variation recorded in tissue glycogen content was discussed in relation to respiratory distress, formation of mucus on the whole fish and disturbed behaviour of the fish. 相似文献
29.
Sneha H. Meshram Tungana Ramesh Jagadeesh Babu Nanubolu Ajay Kumar Srivastava Bhaskar Rao Adari Nivedita Sahu 《Chirality》2019,31(4):312-320
Green chemistry comprises a new approach in the synthesis of biologically active compounds using biocatalysts, thus diminishing the hazards for human health and environmental pollution. Asymmetric bioreduction is one of the most widely employed strategies in chemoenzymatic synthesis to produce enantiomerically pure chiral alcohols. The present study highlights the use biocatalyst Daucus carota for selective bioreduction of quinoxaline ketones 1a‐6a to their corresponding optically pure alcohols 1b‐6b in high yields (up to 84%) and good enantioselectivity (up to 98%). The absolute configuration of the chiral product (R)‐1‐(3‐methyl 7‐nitroquinoxalin‐2‐yl) ethan‐1‐ol 2b was confirmed by X‐ray crystallography studies. The chiral R‐configuration of the products obtained was confirmed by absolute configuration studies and was assigned following anti‐Prelogs rule. Quinoxaline pharmacophores form a part of well‐known potent drug molecules; hence, the chiral products were studied for determination of their molecular properties using SwissADME property analyser. All the chiral products show no Lipinski rule violations and are expected to have good oral bioavailability. As per the molecular properties prediction studies, the compound 6b (R)‐1‐(6,7‐dichloro‐3‐ methylquinoxalin‐2‐yl) ethanol is observed to show the best physicochemical properties to be a good lead molecule. Thus, the sustainable methodology was developed, and it confirms the synthesis of novel quinoxaline chiral alcohols in a simple, inexpensive, and eco‐friendly condition using D carota. 相似文献
30.