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91.
Zafar Iqbal Khan Muhammad Ashraf Muhammad Khalid Mukhtar Nasra Raza Kafeel Ahmad Nudrat Aisha Akram 《Biological trace element research》2011,142(3):890-895
The present investigation on the iron (Fe) transfer from soil to plant and in turn to animal (cows), as a function of sampling
periods was conducted at the Livestock Experimental Station Sargodha, Pakistan which falls under semi-arid conditions. Although
the iron transfer from soil to forage increased consistently, the forage Fe content decreased progressively with increase
in sampling period. Highest Fe transfer from forage to cow blood plasma was observed during October and lowest during January.
The transfer of Fe from forage to animal milk was maximum during the months of October and January and minimum during December.
The transfer of Fe to plasma and milk was found to be dependent variably on the growth stage of forage in this investigation.
Based on the findings of the present study, it is evident that mineral supplementation with higher Fe availability is urgently
warranted to the animals particularly during the months of December and January to enhance plasma Fe in the cows being reared
at that livestock farm during the entire grazing period. Thus, obligatory supplementation of Fe to the ruminants is highly
recommended. Since the processes involved in iron management system in humans, animals, and plants are basically similar,
appropriate elemental management must be provided to the living organisms, otherwise deficient or excessive levels of iron
may deteriorate the developing cells of the organisms. 相似文献
92.
Cheng X Cheng X Mukhtar M Acheampong EA Srinivasan A Rafi M Pomerantz RJ Parveen Z 《DNA and cell biology》2007,26(2):116-131
The human immunodeficiency virus type I (HIV-1) accessory protein Vpr has been associated with the induction of programmed cell death (apoptosis) and cell-cycle arrest. Studies have shown the apoptotic effect of Vpr on primary and established cell lines and on diverse tissues including the central nervous system (CNS) in vitro. However, the relevance of the effect of Vpr observed in vitro to HIV-1 neuropathogenesis in vivo, remains unknown. Due to the narrow host range of HIV-1 infection, no animal model is currently available. This has prompted us to consider a small animal model to evaluate the effects of Vpr on CNS in vivo through surrogate viruses expressing HIV-1Vpr. A single round of replication competent viral vectors, expressing Vpr, were used to investigate the apoptosis-inducing capabilities of HIV-1Vpr in vivo. Viral particles pseudotyped with VSV-G or N2c envelopes were generated from spleen necrosis virus (SNV) and HIV-1-based vectors to transduce CNS cells. The in vitro studies have demonstrated that Vpr generated by SNV vectors had less apoptotic effects on CNS cells compared with Vpr expressed by HIV-1 vectors. The in vivo study has suggested that viral particles, expressing Vpr generated by HIV-1-based vectors, when delivered through the ventricle, caused loss of neurons and dendritic processes in the cortical region. The apoptotic effect was extended beyond the cortical region and affected the hippocampus neurons, the lining of the choroids plexus, and the cerebellum. However, the effect of Vpr, when delivered through the cortex, showed neuronal damage only around the site of injection. Interestingly, the number of apoptotic neurons were significantly higher with HIV-1 vectors expressing Vpr than by the SNV vectors. This may be due to the differences in the proteins expressed by these viral vectors. These results suggest that Vpr induces apoptosis in CNS cells in vitro and in vivo. To our knowledge, this is the first study to investigate the apoptosis-inducing capabilities of HIV-1Vpr in vivo in neonatal mice. We propose that this, in expensive animal model, may be of value to design-targeted neuroprotective therapeutics. 相似文献
93.
Among males, prostate cancer has become the second leading cause of cancer-related deaths in North America, with similar trends
in many Western and developing countries. One way to control prostate cancer is through chemoprevention, which refers to the
administration of synthetic or naturally occurring agents to block, reverse, or delay the process of carcinogenesis. For a
variety of reasons, the most important of which is human acceptance, for chemopreventive intervention, naturally occurring
diet-based agents are preferred. Prostate cancer is an ideal candidate disease for chemopreventive intervention, because it
grows very slowly, likely for decades, before symptoms arise and a diagnosis is finally established, it has a long latency
period, and it is typically diagnosed in men >50 years of age. Most chemopreventive agents are antioxidant in nature. We have
been defining the usefulness of dietary anti-oxidants for chemoprevention of prostate and other cancers. It is increasingly
appreciated that some of these dietary anti-oxidants are nature’s gift molecules endowed with cancer preventive and therapeutic
properties. This review will focus on prostate cancer chemopreventive effects of polyphenolic anti-oxidants derived from green
tea and pomegranate. It is a challenge to custom-tailor these gift molecules as cocktails in concentrations that can easily
be consumed by humans for delaying prostate and other cancers. 相似文献
94.
95.
Abdel Halim Harrath Abdelhabib Semlali Lamjed Mansour Mukhtar Ahmed Alexander V. Sirotkin Suliman Y. Al Omar Maha Arfah Mohamed S. Al Anazi Ibrahim M. Alhazza Jens R. Nyengaard Saleh Alwasel 《Cell and tissue research》2014,358(2):607-620
Ex-fissiparous planarians produce infertile cocoons or, in very rare cases, cocoons with very low fertility. Here, we describe the features of programmed cell death (PCD) occurring in the hyperplasic ovary of the ex-fissiparous freshwater planarian Dugesia arabica that may explain this infertility. Based on TEM results, we demonstrate a novel extensive co-clustering of cytoplasmic organelles, such as lysosomes and microtubules, and their fusion with autophagosomes during the early stage of oocyte cell death occurring through an autophagic pattern. During a later stage of cell death, the generation of apoptotic vesicles in the cytoplasm can be observed. The immunohistochemical labeling supports the ultrastructural results because it has been shown that the proapoptotic protein bax was more highly expressed in the hyperplasic ovary than in the normal one, whereas the anti-apoptotic protein bcl2 was slightly more highly expressed in the normal ovary compared to the hyperplasic one. TUNEL analysis of the hyperplasic ovary confirmed that the nuclei of the majority of differentiating oocytes were TUNEL-positive, whereas the nuclei of oogonia and young oocytes were TUNEL-negative; in the normal ovary, oocytes are TUNEL-negative. Considering all of these data, we suggest that the cell death mechanism of differentiating oocytes in the hyperplasic ovary of freshwater planarians is one of the most important factors that cause ex-fissiparous planarian infertility. We propose that autophagy precedes apoptosis during oogenesis, whereas apoptotic features can be observed later. 相似文献
96.
Mueller AD Pollock MS Lieblich SE Epp JR Galea LA Mistlberger RE 《American journal of physiology. Regulatory, integrative and comparative physiology》2008,294(5):R1693-R1703
Sleep deprivation (SD) can suppress cell proliferation in the hippocampal dentate gyrus of adult male rodents, suggesting that sleep may contribute to hippocampal functions by promoting neurogenesis. However, suppression of cell proliferation in rats by the platform-over-water SD method has been attributed to elevated corticosterone (Cort), a potent inhibitor of cell proliferation and nonspecific correlate of this procedure. We report here results that do not support this conclusion. Intact and adrenalectomized (ADX) male rats were subjected to a 96-h SD using multiple- and single-platform methods. New cells were identified by immunoreactivity for 5-bromo-2'-deoxyuridine (BrdU) or Ki67 and new neurons by immunoreactivity for BrdU and doublecortin. EEG recordings confirmed a 95% deprivation of rapid eye movement (REM) sleep and a 40% decrease of non-REM sleep. Cell proliferation in the dentate gyrus was suppressed by up to 50% in sleep-deprived rats relative to apparatus control or home cage control rats. This effect was also observed in ADX rats receiving continuous low-dose Cort replacement via subcutaneous minipumps but not in ADX rats receiving Cort replacement via drinking water. In these latter rats, Cort intake via water was reduced by 60% during SD; upregulation of cell proliferation by reduced Cort intake may obscure inhibitory effects of sleep loss on cell proliferation. SD had no effect on the percentage of new cells expressing a neuronal phenotype. These results demonstrate that the Cort replacement method is critical for detecting an effect of SD on cell proliferation and support a significant role for sleep in adult neurogenesis. 相似文献
97.
Potential water quality impacts associated with using bottom ash (BA) and composted dairy manure (CM) as a soil amendment were evaluated in this study. Two column studies were conducted to evaluate three blends of acidic BA and CM (BA:CM, v/v) namely, B1ac (95:5), B2ac (90:10), and B3ac (80:20) and three blends of alkaline BA and CM (BA:CM, v/v), namely, B1al (95:5), B2al (90:10), and B3al (80:20) under constant head water table conditions. Samples from standing water (top) and leachate (bottom) were collected at weekly intervals until day 49 to evaluate the effects of different blend ratios and elapsed time on standing water and leachate chemical and physical properties. A higher CM content in both acidic and alkaline blends resulted in higher leachate concentrations for solids and nutrients tested in this study. Alkaline blends had higher standing water and leachate nutrients concentration compared to acidic blends. After day 28, standing water total dissolved solids (TDS) concentrations for all acidic blends was below the USEPA drinking water standard however, TDS value for alkaline blend was always below the standard. Similar trends were also observed for NO3–N and phosphorus (P) concentrations for both blends. Based on these findings, it was concluded that acidic and alkaline blends B1ac, B1al, B2ac and B2al may be considered as a soil amendment material. 相似文献
98.
Asad S Mukhtar Z Nazir F Hashmi JA Mansoor S Zafar Y Arshad M 《Molecular biotechnology》2008,40(2):161-169
A silicon carbide whisker-mediated gene transfer system with recovery of fertile and stable transformants was developed for
cotton (Gossypium hirsutum L.) cv. Coker-312. Two-month-old hypocotyl-derived embryogenic/non-embryogenic calli at different days after subculture were
treated with silicon carbide whiskers for 2 min in order to deliver pGreen0029 encoding GUS gene and pRG229 AVP1 gene, encoding Arabidopsis vacuolar pyrophosphatase, having neomycin phosphotransferaseII (nptII) genes as plant-selectable markers. Three crucial transformation parameters, i.e., callus type, days after subculture and
selection marker concentration for transformation of cotton calli were evaluated for optimum efficiency of cotton embryogenic
callus transformation giving upto 94% transformation efficiency. Within six weeks, emergence of kanamycin-resistant (kmr) callus colonies was noted on selection medium. GUS and Southern blot analysis showed expression of intact and multiple transgene
copies in the transformed tissues. Kanamycin wiping of leaves from T1, T2, and T3 progeny plants revealed that transgenes were inherited in a Mendelian fashion. Salt treatment of T1
AVP1 transgenic cotton plants showed significant enhancement in salt tolerance as compared to control plants. Thus far, this is
first viable physical procedure after particle bombardment available for cotton that successfully can be used to generate
fertile cotton transformants. 相似文献
99.
Mathivanan S Ahmed M Ahn NG Alexandre H Amanchy R Andrews PC Bader JS Balgley BM Bantscheff M Bennett KL Björling E Blagoev B Bose R Brahmachari SK Burlingame AS Bustelo XR Cagney G Cantin GT Cardasis HL Celis JE Chaerkady R Chu F Cole PA Costello CE Cotter RJ Crockett D DeLany JP De Marzo AM DeSouza LV Deutsch EW Dransfield E Drewes G Droit A Dunn MJ Elenitoba-Johnson K Ewing RM Van Eyk J Faca V Falkner J Fang X Fenselau C Figeys D Gagné P Gelfi C Gevaert K Gimble JM Gnad F Goel R Gromov P 《Nature biotechnology》2008,26(2):164-167
100.
Li W Liu Y Mukhtar MM Gong R Pan Y Rasool ST Gao Y Kang L Hao Q Peng G Chen Y Chen X Wu J Zhu Y 《PloS one》2008,3(4):e1985