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151.
152.
Ram S. Verma Amit Chauhan Rajendra C. Padalia Sanjeev K. Jat Sanjog Thul Velusamy Sundaresan 《化学与生物多样性》2013,10(4):628-641
Murraya koenigii (L.) Spreng. (Rutaceae), commonly known as ‘curry leaf tree’, is a popular spice and condiment of India. To explore the diversity of the essential‐oil yield and aroma profile of curry leaf, growing wild in foot and mid hills of north India, 58 populations were collected during spring season. M. koenigii populations were found to grow up to an altitude of 1487 m in north India. Comparative results showed considerable variations in the essential‐oil yield and composition. The essential‐oil yield varied from 0.14 to 0.80% in shade‐dried leaves of different populations of M. koenigii. Analysis of the essential oils by GC and GC/MS, and the subsequent classification by statistical analysis resulted in four clusters with significant variations in their terpenoid composition. Major components of the essential oils of investigated populations were α‐pinene ( 2 ; 4.5–71.5%), sabinene ( 3 ; <0.05–66.1%), (E)‐caryophyllene ( 11 ; 1.6–18.0%), β‐pinene ( 4 ; <0.05–13.6%), terpinen‐4‐ol ( 9 ; 0.0–8.4%), γ‐terpinene ( 8 ; 0.2–7.4%), limonene ( 7 ; 1.1–5.5%), α‐terpinene ( 6 ; 0.0–4.5%), (E)‐nerolidol ( 14 ; 0.0–4.1%), α‐humulene ( 12 ; 0.6–3.5%), α‐thujene ( 1 ; 0.0–2.5%), β‐elemene ( 10 ; 0.2–2.4%), β‐selinene ( 13 ; 0.2–2.3%), and myrcene ( 5 ; 0.5–2.1%). Comparison of the present results with those in earlier reports revealed new chemotypes of M. koenigii in investigated populations from Western Himalaya. The present study documents M. koenigii populations having higher amounts of sabinene ( 3 ; up to 66.1%) for the first time. 相似文献
153.
Seven distinct strains of Clostridium botulinum (type A to G) each produce a stable complex of botulinum neurotoxin (BoNT) along with neurotoxin-associated proteins (NAPs). Type A botulinum neurotoxin (BoNT/A) is produced with a group of NAPs and is commercially available for the treatment of numerous neuromuscular disorders and cosmetic purposes. Previous studies have indicated that BoNT/A complex composition is specific to the strain, the method of growth and the method of purification; consequently, any variation in composition of NAPs could have significant implications to the effectiveness of BoNT based therapeutics. In this study, a standard analytical technique using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) and densitometry analysis was developed to accurately analyze BoNT/A complex from C. botulinum type A Hall strain. Using 3 batches of BoNT/A complex the molar ratio was determined as neurotoxin binding protein (NBP, 124 kDa), heavy chain (HC, 90 kDa), light chain (LC, 53 kDa), NAP-53 (50 kDa), NAP-33 (36 kDa), NAP-22 (24 kDa), NAP-17 (17 kDa) 1:1:1:2:3:2:2. With Bradford, Lowry, bicinchoninic acid (BCA) and spectroscopic protein estimation methods, the extinction coefficient of BoNT/A complex was determined as 1.54 ± 0.26 (mg/mL)?1cm?1. These findings of a reproducible BoNT/A complex composition will aid in understanding the molecular structure and function of BoNT/A and NAPs. 相似文献
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156.
Víctor Hugo Durán-Zuazo José Ramón Francia-Martínez Iván García-Tejero Simón Cuadros Tavira 《农业工程》2013,33(5):272-281
The impact of land-cover types on soil erosion and runoff, as well as on physico-chemical soil properties, was monitored. The study area, an agroforestry landscape was located in Sierra Nevada Mountains in south-eastern Spain. Eight land-cover types were investigated: farmland planted with olive, almond, and cereals; forest with P. halepensis and P. sylvestris; shrubland; grassland; and abandoned farmland. The erosion plots replicated twice were located on hillslopes, where erosion and runoff were measured after 22 storm events. Forest dominated by Pinus stands exhibited significantly the lowest amounts of erosion and runoff, contrasting with abandoned farmland. Olive had higher erosion than did almond, cereals, or grasslands, but with the highest runoff rate under almond groves. The erosion and runoff response to shrubland showed an intermediate situation between forest and farmland–grassland uses. Under forest and shrubland, better soil properties were determined, especially higher organic C and total N, and lower soil-bulk density. Erosion was highly dependent on runoff, bulk density, soil organic C, and the degree of soil surface covered. Thus, the alteration in land cover is essential to an understanding of productivity of soil undergoing erosion, as sustainable planning can mitigate soil-degradation processes in the overall agroforestry landscape. 相似文献
157.
Cristina Teixidó Rosó Marés Miguel Aracil Santiago Ramón y Cajal Javier Hernández-Losa 《PloS one》2013,8(1)
Elisidepsin (elisidepsin trifluoroacetate, Irvalec®, PM02734) is a new synthetic depsipeptide, a result of the PharmaMar Development Program that seeks synthetic products of marine origin-derived compounds. Elisidepsin is a drug with antiproliferative activity in a wide range of tumors. In the present work we studied and characterized the mechanisms associated with sensitivity and resistance to elisidepsin treatment in a broad panel of tumor cell lines from breast and pancreas carcinomas, focusing on different factors involved in epithelial-mesenchymal transition (EMT) and the use of HER family receptors in predicting the in vitro drug response. Interestingly, we observed that the basal protein expression levels of EMT markers show a significant correlation with cell viability in response to elisidepsin treatment in a panel of 12 different breast and pancreatic cancer cell lines. In addition, we generated three elisidepsin treatment-resistant cell lines (MCF-7, HPAC and AsPC-1) and analyzed the pattern of expression of different EMT markers in these cells, confirming that acquired resistance to elisidepsin is associated with a switch to the EMT state. Furthermore, a direct correlation between basal HER3 expression and sensitivity to elisidepsin was observed; moreover, modulation of HER3 expression levels in different cancer cell lines alter their sensitivities to the drug, making them more resistant when HER3 expression is downregulated by a HER3-specific short hairpin RNA and more sensitive when the receptor is overexpressed. These results show that HER3 expression is an important marker of sensitivity to elisidepsin treatment. 相似文献
158.
Domnic Mijele Vincent Obanda Patrick Omondi Ramón C. Soriguer Francis Gakuya Moses Otiende Peter Hongo Samer Alasaad 《PloS one》2013,8(7)
Background
Very few studies have ever focused on the elephants that are wounded or killed as local communities attempt to scare these animals away from their settlements and farms, or on the cases in which local people take revenge after elephants have killed or injured humans. On the other hand, local communities live in close proximity to elephants and hence can play a positive role in elephant conservation by informing the authorities of the presence of injured elephants.Methodology/Principal Findings
Between 2007 and 2011, 129 elephants were monitored in Masai Mara (Kenya), of which 54 had various types of active (intentionally caused) or passive (non-intentionally caused) injuries. Also studied were 75 random control samples of apparently unaffected animals. The observed active injuries were as expected biased by age, with adults suffering more harm; on the other hand, no such bias was observed in the case of passive injuries. Bias was also observed in elephant sex since more males than females were passively and actively injured. Cases of passive and active injuries in elephants were negatively related to the proximity to roads and farms; the distribution of injured elephants was not affected by the presence of either human settlements or water sources. Overall more elephants were actively injured during the dry season than the wet season as expected. Local communities play a positive role by informing KWS authorities of the presence of injured elephants and reported 43% of all cases of injured elephants.Conclusions
Our results suggest that the negative effect of local communities on elephants could be predicted by elephant proximity to farms and roads. In addition, local communities may be able to play a more positive role in elephant conservation given that they are key informants in the early detection of injured elephants. 相似文献159.
Germinal J. Canto Alarcon Yezenia Rubio Venegas Luis Bojorquez Narvaez Oscar E. Pizano Martínez Leticia García Casanova Susana Sosa Gallegos Alejandro Nava Vargas Andrea M. Olvera Ramírez Feliciano Milian Suazo 《PloS one》2013,8(10)
“Test-and-slaughter” has been successful in industrialized countries to control and eradicate tuberculosis from cattle; however, this strategy is too expensive for developing nations, where the prevalence is especially high. Vaccination with the Calmette-Guérin (BCG) strain has been shown to protect against the development of lesions in vaccinated animals: mouse, cattle and wildlife species. In this study, the immune response and the pathology of vaccinated (BCG-prime and BCG prime-CFP-boosted) and unvaccinated (controls) calves were evaluated under experimental settings. A 106 CFU dose of the BCG strain was inoculated subcutaneously on the neck to two groups of ten animas each. Thirty days after vaccination, one of the vaccinated groups was boosted with an M. bovis culture filtrate protein (CFP). Three months after vaccination, the three groups of animals were challenged with 5×105 CFU via intranasal by aerosol with a field strain of M. bovis. The immune response was monitored throughout the study. Protection was assessed based on immune response (IFN-g release) prechallenge, presence of visible lesions in lymph nodes and lungs at slaughter, and presence of bacilli in lymph nodes and lung samples in histological analysis. Vaccinated cattle, either with the BCG alone or with BCG and boosted with CFP showed higher IFN-g response, fewer lesions, and fewer bacilli per lesion than unvaccinated controls after challenge. Animals with low levels of IFN-g postvaccine-prechallenge showed more lesions than animals with high levels. Results from this study support the argument that vaccination could be incorporated into control programs to reduce the incidence of TB in cattle in countries with high prevalence. 相似文献
160.
Priyanka Jha Swati Chahal Devendra Kumar Pandey Joginder Singh Ram Prasad Vijay Kumar 《Phyton》2020,89(4):779-794
The use of medicinal plants for different therapeutic values is well
documented in African continent. African diverse biodiversity hotspots provide
a wide range of endemic species, which ensures a potential medicinal value.
The feasible conservation approach and sustainable harvesting for the medicinal
species remains a huge challenge. However, conservation approach through different biotechnological tools such as micropropagation, somatic embryogenesis,
synthetic seed production, hairy root culture, molecular markers based study
and cryopreservation of endemic African medicinal species is much crucial. In
this review, an attempt has been made to provide different in vitro biotechnological approaches for the conservation of African medicinal species. The present
review will be helpful in further technology development and deciding the priorities at decision-making levels for in vitro conservation and sustainable use of
African medicinal species. 相似文献