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991.
Chinsriwongkul A Chareanputtakhun P Ngawhirunpat T Rojanarata T Sila-on W Ruktanonchai U Opanasopit P 《AAPS PharmSciTech》2012,13(1):150-158
The purpose of this research was to formulate nanostructured lipid carriers (NLC) for the parenteral delivery of an anticancer
drug, all-trans retinoic acid (ATRA). The ATRA was incorporated into NLC by the de novo emulsification method. The effect of the formulation
factor, i.e., type and oil ratio, initial ATRA concentration on physicochemical properties was determined. The anticancer
efficacy of ATRA-loaded NLC on HL-60 and HepG2 cells was also studied. NLC was formulated using a blend of solid lipids (cetyl
palmitate) and liquid lipids (soybean oil (S), medium-chain triglyceride (M), S/oleic acid (O; 3:1) and M/O (3:1)) at a weight
ratio of 1:1. ATRA-loaded NLC had an average size of less than 200 nm (141.80 to 172.95 nm) with a narrow PDI and negative
zeta potential that was within an acceptable range for intravenous injection. The results indicated that oleic acid enhanced
the ATRA-loading capacity of NLC. In vitro ATRA release was only approximately 4.06% to 4.34% for 48 h, and no significant difference in ATRA release rate from all
NLC formulations in accordance with the composition of the oil phase. Moreover, no burst release of the drug was observed,
indicating that NLC could prolong the release of ATRA. The initial drug concentration affected the photodegradation rate but
did not affect the release rate. All ATRA-loaded NLC formulations exhibited the photoprotective property. The cytotoxicity
results showed that all ATRA-loaded NLC had higher cytotoxicity than the free drug and HL-60 cells were more sensitive to
ATRA than HepG2 cells. 相似文献
992.
Christina A. Olson Karen H. Beard David N. Koons William C. Pitt 《Biological invasions》2012,14(4):889-900
Two nonnative Caribbean frogs, the Puerto Rican coqui and the Cuban greenhouse frog, recently invaded Hawaii. Because of its
louder breeding call, management efforts have focused on the coqui, while little has been done to address the more cryptic
greenhouse frog, even though it may be as widespread and have similar ecological impacts. The goal of this research was to
determine the distribution and detection probability of both species on the island of Hawaii. We conducted a breeding call
presence/absence survey at 446 sites every 2 km along major road networks. We re-surveyed 125 sites twice to determine detection
and occupancy probabilities. Greenhouse frog detection probabilities (0.24, 0.29, 0.48, for each of the three visits, respectively)
were lower than coqui detection probabilities (0.58, 0.73, 0.50, respectively) and increased with visits while those of the
coqui did not. Greenhouse frog detection probabilities were lower in the presence of coquis for the first two surveys (0.12,
0.14) than in sites with greenhouse frogs alone (0.41), while greenhouse frogs had no effect on the detection of coquis. Site
occupancy estimates for the greenhouse and coqui frog were 0.35 and 0.31, respectively, suggesting the species are similarly
widespread. Results suggest multiple visits to sites are required to detect the greenhouse frog. Furthermore, results suggest
that accounting for detectability is essential when determining the extent of invasion of cryptic species. 相似文献
993.
Rb1 and Rg1 are the major ginsenosides in protopanaxadiol and protopanaxatriol. Their content in ginsenosides was 23.8 and 17.6%, respectively.
A total of 22 isolates of β-glucosidase producing microorganisms were isolated from the soil of a ginseng field using Esculin-R2A
agar. Among these isolates, the strain GH21 showed the strongest activities to convert ginsenoside Rb1 and Rg1 to minor ginsenosides compound-K and F1, respectively. Ginsenosides Rb1 and Rg1 bioconversion rates were 74.2 and 89.3%, respectively. Meanwhile, the results demonstrated that the ginsenoside Rg1 could change the biotransformation pathway of ginsenoside Rb1 by inhibiting the formation of the intermediate metabolite gypenoside-XVII. GH21 was identified as a Cladosporium cladosporioides species based on the internal transcribed spacers (ITS) ITS1-5.8S-ITS2 rRNA gene sequences constructed phylogenetic trees. 相似文献
994.
Cho SY Jeong EM Lee JH Kim HJ Lim J Kim CW Shin DM Jeon JH Choi K Kim IG 《Molecules and cells》2012,33(3):235-241
The activation of transglutaminase 2 (TG2), an enzyme that catalyzes post-translational modifications of proteins, has been
implicated in apoptosis, cell adhesion and inflammatory responses. We previously reported that intracellular TG2 is activated
under oxidative stress conditions, such as ultraviolet irradiation, ischemia-reperfusion, and hypoxia. In this study, we examined
the effect of genotoxic stress on the intracellular activity of TG2 using doxorubicin which generates reactive oxygen species
that lead to double-strand breakage of DNA. We demonstrated that doxorubicin elicits the persistent activation of TG2. Doxorubicin-induced
TG2 activity was suppressed by treatment with caffeine at the early phase, N-acetylcysteine at the mid-phase, and EGTA at
the late phase. However, treatment with a blocking antibody against TGFβ or toll-like receptor 2 showed no effect on TG2 activity,
indicating that at least three different signaling pathways may be involved in the process of TG2 activation. In addition,
using MEF cells defective for TG2 and cells overexpressing an activesite mutant of TG2, we revealed that doxorubicin-induced
cell death is inversely correlated with TG2 activity. Our findings indicate that the persistent activation of TG2 by doxorubicin
contributes to cell survival, suggesting that the mechanism-based inhibition of TG2 may be a novel strategy to prevent drug-resistance
in doxorubicin treatment. 相似文献
995.
Autophagy is an evolutionary conserved process of bulk degradation and nutrient sequestration that occurs in all eukaryotic
cells. Yet, in recent years, autophagy has also been shown to play a role in the specific degradation of individual proteins
or protein aggregates as well as of damaged organelles. The process was initially discovered in yeast and has also been very
well studied in mammals and, to a lesser extent, in plants. In this review, we summarize what is known regarding the various
functions of autopahgy in plants but also attempt to address some specific issues concerning plant autophagy, such as the
insufficient knowledge regarding autophagy in various plant species other than Arabidopsis, the fact that some genes belonging to the core autophagy machinery in various organisms are still missing in plants, the
existence of autophagy multigene families in plants and the possible operation of selective autophagy in plants, a study that
is still in its infancy. In addition, we point to plant-specific autophagy processes, such as the participation of autophagy
during development and germination of the seed, a unique plant organ. Throughout this review, we demonstrate that the use
of innovative bioinformatic resources, together with recent biological discoveries (such as the ATG8-interacting motif), should
pave the way to a more comprehensive understanding of the multiple functions of plant autophagy. 相似文献
996.
In this study, loop-mediated isothermal amplification (LAMP)-based molecular marker was developed for authentication of Catharanthus roseus, a medicinal plant. Samples of this plant were collected from different geographical locations in India. Random amplified
polymorphic deoxyribonucleic acid (DNA) analysis of collected samples was carried out with 25 random primers. A 610-bp DNA
fragment, common to all accessions, was eluted, cloned, and sequenced. Four LAMP primers were designed on the basis of sequence
of 610 bp DNA fragment. LAMP reaction, containing 10× Bst DNA polymerase reaction buffer, Bst DNA polymerase, four in-house designed primers, dNTPs, MgSO4, and betaine, was incubated at 65°C for 1 h. The resulting amplicon was visualized by adding SYBR Green I to the reaction
tube. The data showed confirmatory results. Since the assay method is simple, sensitive, and cost-effective, it is a feasible
method for identifying and authentication of C. roseus. 相似文献
997.
Anirban Guha Debashree Sengupta Girish Kumar Rasineni Attipalli Ramachandra Reddy 《Trees - Structure and Function》2012,26(3):903-918
The present study investigated drought-induced responses of non-enzymatic antioxidants in four diverse mulberry genotypes (Morus indica L. S-36, M-5, MR-2 and V-1). Inside the glasshouse, potted plants were subjected to four water regimes for 75 days: (a) control: pots maintained at 100% pot water holding capacity (PC) (b) low water stress: 75% PC (c) medium water stress: 50% PC and (d) high water stress: 25% PC. Photosynthetic leaf gas exchange and non-enzymatic antioxidants including α-tocopherol, ascorbic acid (AA), glutathione, proline and total carotenoids were measured in leaves at regular intervals. Amongst all, V-1 was relatively drought tolerant and showed exceeded accumulation of α-tocopherol and AA-glutathione pool in association with higher carotenoids and proline contents. Susceptible S-36, M-5 and MR-2 could not induce any significant up-regulation in AA-glutathione pool leading to endogenous loss of α-tocopherol and more lipid peroxidation. Reactive oxygen species (ROS) like hydrogen peroxide (H2O2) and superoxide (O2 · ?) showed apparent accumulation in water-stressed leaves and significantly contributed to lipid peroxidation in susceptible genotypes when compared to V-1. Our study demonstrated that proline, AA and glutathione were the major non-enzymatic antioxidants in mulberry with α-tocopherol and carotenoids as good additional indicators for drought stress tolerance. These non-enzymatic antioxidants can cumulatively render effective protection against oxidative damage and can be considered as reliable markers for screening drought-tolerant mulberry genotypes. 相似文献
998.
Numerous invasive aquatic species introductions can be traced to the aquarium trade. Many potentially harmful aquarium species
may be difficult to identify based on morphology alone. As such, some prohibited or invasive species may be available for
purchase if they are mislabeled as species without restrictions. Here we compare molecular identifications to internet vendors’
identifications for accessions of a popular genus of aquarium plants that are difficult to distinguish morphologically (Myriophyllum; watermilfoils). Specifically, we identified the extensive mislabeling of M. heterophyllum—an invasive species in the northeastern and western US. Furthermore, genotypes of M. heterophyllum found in our aquarium survey have also been found in invasive populations, suggesting their potential introduction through
escape from aquaria, water gardens, or nurseries. Two additional taxa were sold under incorrect names. Finally, our survey
revealed that Myriophyllum taxa present in the aquarium trade generally have poorly known distributions and ecologies, and therefore their invasive
potential is unknown. Our study confirms that molecular identification methods can provide a valuable tool to survey commercial
pathways for potentially harmful species that are otherwise difficult to identify. 相似文献
999.
A wide number of pesticides, including highly persistent organochlorine compounds, such as lindane (γ-Hexachlorocyclohexane),
have deteriorative effect on fauna and flora by inducing oxidative stress. Lindane induces cell damage by producing free radicals
and reactive oxygen species. Quercetin, a dietary flavonoid, is ubiquitous in fruits and vegetables and plays an important
role in human health by virtue of its antioxidant function. In this study the flavonoid quercetin was used to investigate
its antioxidative effect against lindane induced oxidative stress in rats. The level of lipid peroxidation, reduced glutathione
(GSH) were analysed in addition to the antioxidant enzymes such as catalase (CAT), glutathione peroxidase (GPx), superoxide
dismutase (SOD) and glutathione-s-transferase (GST) activities in the liver and kidney tissue. Levels of hepatic marker enzymes
in serum like Aspartate transaminase (AST), Alanine transaminase (ALT), Alkaline phosphatase (ALP) and Lactate dehydrogenase
(LDH) and renal markers like serum creatinine and serum urea were estimated. Administration of Lindane induced histopathological
alterations and increased levels of serum hepatic and renal markers and malondialdehyde (MDA) with a significant decrease
in GSH content and CAT, SOD, GPx and GST activities. Cotreatment of quercetin along with lindane significantly decreased the
lindane induced alteration in histology, serum hepatic and renal markers and MDA and also improved the cellular antioxidant
status. The results show that Quercetin ameliorates Lindane induced oxidative stress in liver and kidney. The quercetin exhibited
chemopreventive effect when administered along with lindane. 相似文献
1000.