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81.
Deepak Jose Harikrishnan Mahadevan Anupama Kalathil Mukundan 《Zeitschrift fur angewandte Ichthyologie》2021,37(2):246-257
Carinotetraodon travancoricus or Malabar puffer fish is an endemic species described from rivers originating from the Western Ghats in South India. This species is captured extensively as an aquarium fish and is having substantial demand in global markets. However, being prone to overfishing and impacts of anthropogenic alterations in its habitats, IUCN has categorized it as a threatened/vulnerable species. Since, knowledge on variability of wild populations could help in their conservation and management, morphometric and genotypic analyses were carried out in natural populations of C. travancoricus inhabiting two geographically separated rivers Pamba and Chalakkudy. Mean values of eleven length parameters measured in 456 males and 439 females inhabiting these rivers revealed significant difference (ANOVA, F = 10.2 p < .001) between sexes and between females inhabiting two rivers. Principal component analysis revealed two factors in males and three factors in females, explained variance of 83.62% and 89.94% in respective sexes. Results of both PCA and discriminant function analysis indicated perceptibly high degree of separation between individuals inhabiting the two rivers. A total of 25 COI sequences were generated from C. travancoricus collected from rivers Pamba (n = 14) and Chalakkudy (n = 11). Sequence alignment revealed considerable base substitutions between samples from both rivers, indicating possibility of population differences. AMOVA analysis also provided significant Fst value (0.622; p-value .00) in support of population difference between individuals of both rivers. Interpopulation genetic distance reached upto 2.50%, high enough to confirm genetic diversity among individuals, revealing perceptible population events within this species. The present results indicated high degree of population difference between C. travancoricus inhabiting geographically separated rivers Pamba and Chalakkudy as evidenced from both morphometric and genotypic analyses. 相似文献
82.
Reactions of sulfasalazine (SAZ) and its metabolites, 5-aminosalicylic acid (5-ASA) and sulfapyridine (SP), with various oxidizing and reducing free radicals (hydroxyl, haloperoxyl, one-electron oxidizing, lipid peroxyl, glutathiyl, superoxide, tryptophanyl, etc.) have been studied to understand the mechanistic aspects of its action against free radicals produced during inflammation. Nanosecond pulse radiolysis technique coupled with transient spectrophotometry has been used for in situ generation of free radicals and to follow their reaction pathways. The transients produced in these reactions have been assigned and radical scavenging rate constants have been measured. In addition to scavenging of various primary and secondary free radicals by SAZ, 5-ASA and SP, 5-ASA has also been observed to efficiently scavenge radicals of biomolecules. 5-ASA has been found to be the active moiety of SAZ involved in the scavenging of oxidizing free radicals whereas reduction of SAZ produced molecular radical anion. The study suggests that free radical scavenging activity of 5-ASA may be a major path of pharmacological action of SAZ against inflammatory bowel diseases (IBD). 相似文献
83.
The vessel member length-diameter and perforation plate-vessel member length relations inDioscorea alata L. have been investigated. The two types of vessel elements, one with scalariform perforation plate and the other with foraminate perforation plate, have been considered for correlation tests; the variables being vessel member length and diameter, and vessel member length and perforation plate length. Significant positive correlation was found only in the case of perforation plate length and vessel member length for types with scalariform perforation plates. 相似文献
84.
The incorporation of [35S]-SO4 into glycosaminoglycans of liverin vivo and in in liver slices and into the glycosaminoglycans associated with the hepatic plasma membrane of rats at different periods
after a heavy dose of CC14 have been studied. The incorporation of [35S]-SO4 into total glycosaminoglycans decreased to as low as 40% of the control
at 24 h after the administration of CC14 and later on increased reaching a maximum on the 4th day. The amount of [35S]-SO4
incorporation into heparan sulphate was also reduced to about 40% of control at 12–24 h after the onset of injury and increased
thereafter reaching a maximum on the 4th day. There was only a partial reduction in the synthesis of chondroitin sulphate
in the early stage of injury and then it steadily increased reaching about 3 times the control level on 4–6 days. The [35S]-SO4-incorporation into dermatan sulphate, after a slight initial decrease remained at the control levels. On the 8th day
after the CCl4-induced liver injury, the rate of [35S]-SO4-incorporation was almost equal to that in normal controls. The incorporation of [35S]-SO4 into hepatic plasma membrane glycosaminoglycans showed a similar change decreasing to about 35% of control at 24h followed
by an increase, reaching normal levels on the 4th day after the administration of CC14. About 90% of the plasma membrane glycosaminoglycans was found to be heparan sulphate. The yield of plasma membrane from
normal and CCl4-induced regenerating liver was found to be similar and therefore the results obtained were not due to difference in the yield
of the membrane preparation. The data also indicate that there was no difference in the degree of sulphation. The significance
of these changes in the metabolism of sulphated glycosaminoglycans particularly plasma membrane heparan sulphate in tissue
regeneration has been discussed. 相似文献
85.
G. Paliyath I. Rajagopal P. O. Unnikrishnan S. Mahadevan 《Journal of Plant Growth Regulation》1989,8(1):19-35
Transport of 1-14C-IAA in successive stem segments ofCuscuta was strictly basipetal in growing and non growing regions of the vine with a flux velocity of 10–12 mm/h (intercept method). This transport showed a distinct peaked profile, increasing from a low value at 10 mm from the apex to a maximum between 50 and 90 mm before declining to a low value again around 160 mm at which elongation growth ceased. The IAA transport profile paralleled the in vivo growth rate profile, though the latter peaked ahead of transport. A better correlation was observed between the profile of growth responsiveness of the vine to exogenous IAA application and the profile of IAA transport. Growth responsiveness was determined as the differential in growth rate of stem segments in vitro in the absence and presence of growth optimal concentration of IAA (10 m). Retention of exogenous IAA in the stem was maximal where transport decreased, and this coincided with the region of maximal conjugation of applied 1-14C-IAA to aspartic acid to form indoleacetylaspartate (IAAsp). In addition to aspartate, IAA was conjugated to a small extent to an unidentified compound. IAA destruction by decarboxylation was greatest where transport was low, particularly in the nongrowing region, where lignification occurred (i.e., beyond 180 mm). At concentrations up to 20 M, a pulse of 1-14C-IAA chased by cold IAA moved as a peak (with a peak displacement velocity of 12–18 mm/h) in the growth region of the vine, but became diffusionlike where growth either fell off steeply or ceased. At a higher (50 M) IAA concentration, though uptake was not saturated, transport in the growth region became diffusionlike, indicating saturation of the system. Reduced IAA flux in the region where growth responsiveness to IAA declined coincided with the region of increased IAA conjugation. However, it cannot be concluded whether increased IAA conjugation was the cause or effect of decreased IAA flux. Application of benzyladenine to the vines in vivo, a treatment that elicited haustoria formation by 72 h, resulted in the inhibition of both IAA transport and elongation growth rate in the subapical region. In vitro treatment of vine segments with BA similarly increased IAA retention and decreased IAA transport. IAA loss was suppressed, and conjugation to IAAsp was enhanced. 相似文献
86.
Lung-Hsiang Peng Binesh Unnikrishnan Chi-Yu Shih Tung-Ming Hsiung Jeng Chang Pang-Hung Hsu Tai-Chia Chiu Chih-Ching Huang 《Marine biotechnology (New York, N.Y.)》2016,18(2):283-292
In this study, we demonstrate a simple method to identify microalgae by surface-assisted laser desorption/ionization mass spectrometry (SALDI-MS) using three different substrates: HgSe, HgTe, and HgTeSe nanostructures. The fragmentation/ionization processes of complex molecules in algae varied according to the heat absorption and transfer efficiency of the nanostructured matrices (NMs). Therefore, the mass spectra obtained for microalgae showed different patterns of m/z values for different NMs. The spectra contained both significant and nonsignificant peaks. Constructing a Venn diagram with the significant peaks obtained for algae when using HgSe, HgTe, and HgTeSe NMs in m/z ratio range 100–1000, a unique relationship among the three sets of values was obtained. This unique relationship of sets is different for each species of microalgae. Therefore, by observing the particular relationship of sets, we successfully identified different algae such as Isochrysis galbana, Emiliania huxleyi, Thalassiosira weissflogii, Nannochloris sp., Skeletonema cf. costatum, and Tetraselmis chui. This simple and cost-effective SALDI-MS analysis method coupled with multi-nanomaterials as substrates may be extended to identify other microalgae and microorganisms in real samples. 相似文献
87.
Sruthi Venkataramanababu Manav Shah Harikrishnan Vasudevan Kannan Ramaswamy 《Plasmonics (Norwell, Mass.)》2016,11(6):1467-1473
In this article, we have developed an optimization strategy taking into consideration the interplay between the choice of plasmonic material and geometrical parameters that lead to enhanced photocurrent density. We have demonstrated this by computing the optical absorption, using finite difference time domain technique, due to front-end placed aluminum and silver nanosphere arrays on 1- μm-thick film of silicon. Results from this optimization procedure indicate that over a broad wavelength range (~600 nm onwards), absorption enhancement is primarily due to waveguiding effects and is independent of the plasmonic material. However, the significance of the plasmonic material becomes noticeable at lower wavelengths. The optimization yielded an inter-particle distance of 325 nm and nanosphere radius of 75 nm that corresponds to maximum photocurrent density for both aluminum and silver. Furthermore, it was noticed that the presence of a native oxide layer on aluminum does not deteriorate the enhancement significantly. In fact, the photocurrent density enhancement due to partially oxidized aluminum nanospheres is found to be better than using silver nanospheres. 相似文献
88.
The goal of this study is to quantify the effects of vocal fold nodules on vibratory motion in children using high-speed videoendoscopy. Differences in vibratory motion were evaluated in 20 children with vocal fold nodules (5–11 years) and 20 age and gender matched typically developing children (5–11 years) during sustained phonation at typical pitch and loudness. Normalized kinematic features of vocal fold displacements from the mid-membranous vocal fold point were extracted from the steady-state high-speed video. A total of 12 kinematic features representing spatial and temporal characteristics of vibratory motion were calculated. Average values and standard deviations (cycle-to-cycle variability) of the following kinematic features were computed: normalized peak displacement, normalized average opening velocity, normalized average closing velocity, normalized peak closing velocity, speed quotient, and open quotient. Group differences between children with and without vocal fold nodules were statistically investigated. While a moderate effect size was observed for the spatial feature of speed quotient, and the temporal feature of normalized average closing velocity in children with nodules compared to vocally normal children, none of the features were statistically significant between the groups after Bonferroni correction. The kinematic analysis of the mid-membranous vocal fold displacement revealed that children with nodules primarily differ from typically developing children in closing phase kinematics of the glottal cycle, whereas the opening phase kinematics are similar. Higher speed quotients and similar opening phase velocities suggest greater relative forces are acting on vocal fold in the closing phase. These findings suggest that future large-scale studies should focus on spatial and temporal features related to the closing phase of the glottal cycle for differentiating the kinematics of children with and without vocal fold nodules. 相似文献
89.
Genus Anthessius includes 36 species. Previous attempts to clarify the interspecific affinities reached no definite conclusions. Humes and Ho (1965) found that, based on the armature of the third exopod segment of the fourth leg, the known species could be arranged into two groups, but that this difference did not correspond with host preferences. The present study of A. alatus Humes and Stock shows that species of Anthessius associated with Tridacnidae differ from the rest (except A. fitchi Illg) in the marked indentation of the cephalosome and in the presence of well developed cephalosomal and metasomal epimeral lobes producing a very characteristic shape. They are here removed to a new genus, Tridachnophilus. 相似文献
90.
S. Indumathi Rashmi Mishra R. Harikrishnan J. S. Rajkumar Neha Kantawala M. Dhanasekaran 《Cytotechnology》2014,66(2):219-228
The therapeutic rationale for tissue repair and regeneration using stem cells is at its infancy and needs advancement in understanding the role of individual component’s innate capability. As stem cells of adipose tissue reside in a more heterogeneous population of stromal vascular fractions, cell separation or sorting becomes an eminent step towards revealing their unique properties. This study elucidates the comparative efficacy of lineage depleted adipose derived stromal vascular fraction (SVF) and their innate ability using magnetic activated cell sorter (MACS). To this end, isolated SVF from human adipose tissue was lineage depleted according to the manufacturer’s instructions using specific antibody cocktail through MACS. The enriched lineage negative (lin−) and lineage positive (lin+) cell fractions were cultured, phenotypically characterized for the panel of cell surface markers using flowcytometry and subjected to osteoblastic and adipogenic differentiation. The expression profile obtained for lin− cells was CD34−/CD45−/HLADR−/CD49d−/CD140b−/CD31−/CD90+/CD105+/CD73+/CD54+/CD166+/CD117− when compared to Lin+ cells expressing CD34+/CD45+/HLADR−/CD49d−/CD140b+/CD31−/CD90+/CD105+/CD73+/CD54+/CD166+/CD117+ (CD—cluster of differentiation). These results, thus, advances our understanding on the inherent property of the individual cell population. Furthermore, both the fractions exhibited mesodermal lineage differentiation capacity. To conclude, this research pursuit rationalized the regenerative therapeutic applicability of both lin− and lin+ cultures of human adipose tissue for disorders of mesodermal, haematological and vascular origin. 相似文献