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1.
The effects of protein malnutrition on responsiveness of macrophages to proteosepeptone stimulation and on their chemical
composition were investigated. Relative number of resident macrophages in rat peritoneal cavity was reduced by about 50 %
during 4 weeks on 3 % protein diet. Similarly, decreased migration capacity of the circulating macrophages to the peritoneal
exudate in response to the stimulant, was observed in protein-fasted rat compared to that in the 20 % protein-fed group. Further,
the chemical composition of the isolated elicited cells was determined. Total proteins, sugars, lipids and nucleic acids were
significantly low in the cells isolated from protein-deficient animals, though the cell size was not affected. However, cholesterol:
phospholipid molar ratios were distinctly higher than that in control and increased progressively in the 3 and 8 % protein-fed
animals. The implications of these structural changes in macrophages on their functional capability are discussed 相似文献
2.
Molybdate agar was fortified with 0.125% calcium propionate and used for routine isolation and differentiation of a variety of yeasts from mixed floras including large numbers of fungi and actinomycetes inhabiting tropical fruits. The results suggest that this technique could be usefully incorporated in yeast isolation and identification procedures. 相似文献
3.
Dmitry Suplatov Evgeny Kirilin Vakil Takhaveev 《Journal of biomolecular structure & dynamics》2013,31(11):1752-1758
During evolution of proteins from a common ancestor, one functional property can be preserved while others can vary leading to functional diversity. A systematic study of the corresponding adaptive mutations provides a key to one of the most challenging problems of modern structural biology – understanding the impact of amino acid substitutions on protein function. The subfamily-specific positions (SSPs) are conserved within functional subfamilies but are different between them and, therefore, seem to be responsible for functional diversity in protein superfamilies. Consequently, a corresponding method to perform the bioinformatic analysis of sequence and structural data has to be implemented in the common laboratory practice to study the structure–function relationship in proteins and develop novel protein engineering strategies. This paper describes Zebra web server – a powerful remote platform that implements a novel bioinformatic analysis algorithm to study diverse protein families. It is the first application that provides specificity determinants at different levels of functional classification, therefore addressing complex functional diversity of large superfamilies. Statistical analysis is implemented to automatically select a set of highly significant SSPs to be used as hotspots for directed evolution or rational design experiments and analyzed studying the structure–function relationship. Zebra results are provided in two ways – (1) as a single all-in-one parsable text file and (2) as PyMol sessions with structural representation of SSPs. Zebra web server is available at http://biokinet.belozersky.msu.ru/zebra. 相似文献
4.
Effect of simvastatin on fracture healing--an experimental study 总被引:2,自引:0,他引:2
Left femur was osteotomized and fixed with K wire in 21 rabbits. One group was fed simvastatin (120 mg/kg body wt/day) orally, whereas another group without medication served as control. Both groups were assessed radiologically, morphologically, histologically and biomechanically at 4, 8 and 12 weeks. An analysis of various parameters of study showed that simvastatin treated group had improved bone healing at 4 and 8 weeks of follow up, however, the difference was not significant statistically at 12 weeks. So it is concluded that Simvastatin favourably hastened the process of fracture healing in the rabbits at earlier phases. 相似文献
5.
6.
Summary The effect of different concentrations of CO2 on the germination of conidiospores of Aspergillus niger A 5 has been studied using Pardee's buffer mixtures which maintain constant CO2 tensions. The beneficial effect of CO2 on germination is maximum at 0.5% CO2 concentration, when 70–90% of the spores germinate within 6 hours, whereas in controls with air containing 0.03% CO2 there is only 15–20% germination at 6 hours. At higher CO2 concentrations this beneficial effect of CO2 on germination diminishes and at 3% there is a complete inhibition of spore germination.The spore density and the ph of the medium have a noticeable effect on germination rates in presence of 0.5% CO2. The germination rates decrease at spore densities higher than 5 · 105/ml and at a ph of 6.8.Communication No. 431. 相似文献
7.
Randall CN Strasburger D Prozonic J Morris SN Winkie AD Parker GR Cheng D Fennell EM Lanham I Vakil N Huang J Cathcart H Huang R Poduslo SE 《Neurochemical research》2009,34(1):23-28
Multiple genetic variants may contribute to the risk of developing Alzheimer’s disease. We have analyzed polymorphisms in
9 genes to determine whether particular combinations would contribute to this risk. The genes were APOE, LDLr, CST3, CTSD,
TNF, BACE1, MAPT, STH, eNOS, and TFCP2. Three risk groups for the disease were identified. Risk group I was younger, was heterozygous
for the CST3 (GA), CTSD2936 (AG), TNF -308 (AG) genetic variants. Risk group II was older, was homozygous for the −427 APOE
promoter polymorphism (TT), and heterozygous for the MAPT deletion and for the STH variant (QR). Group III had both the youngest
and oldest subjects, were heterozygous for the −863 (AC) and −1031 (CT) TNF promoter polymorphisms. All three groups carried
the APOE 4 allele and were heterozygous for both BACE1 polymorphisms. The control groups were carriers of the APOE 3 allele
and were homozygous for the BACE1 genetic variants.
C. N. Randall, S. N. Morris, A. D. Winkie and G. R. Parker—STAR students.
C. N. Randall, D. Strasburger, J. Prozonic, S. N. Morris, A. D. Winkie, G. R. Parker, D. Cheng and E. M. Fennell contributed
equally to this study.
Special issue article in honor of Dr. George DeVries. 相似文献
8.
9.
Lili Tian Jianming Chen Mingliang Chen Chloe Gui Chuan-qi Zhong Lixin Hong Changchuan Xie Xiurong Wu Lirong Yang Vakil Ahmad Jiahuai Han 《The Journal of biological chemistry》2014,289(46):31856-31865
The p38 pathway is an evolutionarily conserved signaling pathway that responds to a variety of stresses. However, the underlying mechanisms are largely unknown. In the present study, we demonstrate that p38b is a major p38 MAPK involved in the regulation of oxidative stress tolerance in addition to p38a and p38c in Drosophila. We further show the importance of MK2 as a p38-activated downstream kinase in resistance to oxidative stresses. Furthermore, we identified the iron-sulfur cluster scaffold protein IscU as a new substrate of MK2 both in Drosophila cells and in mammalian cells. These results imply a new mechanistic connection between the p38 pathway and mitochondria iron-sulfur clusters. 相似文献
10.
Glutamatergic Activation of Hippocampal Phospholipase D: Postnatal Fading and Receptor Desensitization 总被引:1,自引:1,他引:0
Jochen Klein Marjan Vakil Frits Bergman Thomas Holler Mario Iovino Konrad Löffelholz 《Journal of neurochemistry》1998,70(4):1679-1685
Abstract: Phospholipase D (PLD) activity was determined in rat hippocampal slices between postnatal days 3 and 35. After birth, basal PLD activity was low and, within 2 weeks, increased to reach a plateau that was maintained up to the adult age. Likewise the response to glutamate developed postnatally to reach a maximum at day 8, but then faded rapidly and was almost absent at day 35. Activation of PLD by 4β-phorbol 12β,13α-dibutyrate (PDB) was independent of age, whereas the effect of aluminum fluoride (AlF4 − ) increased to a plateau within the first week. At day 8, PLD stimulation by glutamate via metabotropic receptors involved protein kinase C activation, but was independent of Ca2+ influx; the time course of PLD activation by PDB or AlF4 − was linear throughout the experiment, whereas the response to glutamate or 1-aminocyclopentane-1,3-dicarboxylic acid followed a biphasic pattern: the rapid "first phase activation" desensitized within a few minutes and disclosed a small, but maintained "second phase." Pretreatment experiments confirmed desensitization of PLD activation by glutamate, but not by AlF4 − or PDB. The biphasic pattern of glutamatergic PLD activation changed during development, i.e., the first phase activation faded and the second phase remained. These results were fully confirmed by the time courses of the PLD-mediated efflux of choline evoked by glutamate. In conclusion, postnatal glutamatergic activation of hippocampal PLD is composed of a pronounced and desensitizing first phase activation and a small, but nondesensitizing second phase. The first, but not the second, phase activation fades rapidly during development. The hypothesis is discussed that the glutamatergic activation of PLD occurs along different pathways in neonate and adult tissue. 相似文献