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251.
252.
Mohamed-Elamir F. Hegazy Tarik A. Mohamed Fathy F. Abdel-Latif Mansour S. Alsaid Abdelaaty A. Shahat Paul W. Paré 《Phytochemistry letters》2013,6(3):383-386
Chemical investigations of the soft coral Sarcophyton trocheliophorum, has led to the isolation of six cembranoids, two of which are new, Trochelioid A (1) and B (2), and one, 16-oxosarcophytonin E (3) isolated from nature for the first time. Additionally, two have been isolated from S. trocheliophorum for the first time (4 and 6). Structures were elucidated by employing extensive NMR and HR-FAB-MS experimentation. 相似文献
253.
Lamiaa A. Shaala Diaa T.A. Youssef Kerry L. McPhail Mohamed Elbandy 《Phytochemistry letters》2013,6(2):183-188
In our continuing effort to discover new drug leads from Red Sea marine organisms, a sample of the marine cyanobacterium Moorea producens (previously Lyngbya majuscula) was investigated. Bioassay-directed purification of a tumor cell-growth inhibitory fraction of the organic extract of the Red Sea cyanobacterium afforded a new compound, malyngamide 4 (1), together with five previously reported compounds, malyngamide A (2) and B (3), (S)-7-methoxytetradec-4(E)-enoic acid (lyngbic acid, 4), aplysiatoxin (5) and debromoaplysiatoxin (6). Assignment of the planar structures of these compounds was based on extensive analysis of one- and two-dimensional NMR spectra and high-resolution mass spectrometric data. The isolated compounds were evaluated for their inhibitory activity against three cancer cell lines. In addition, the antibacterial activity of the compounds against Mycobacterium tuberculosis H37Rv ATCC 27294 (H37Rv) was evaluated. Lyngbic acid (4) was the most active against M. tuberculosis, while malyngamides 4 (1) and B (3) moderately inhibited the cancer cell lines. The other compounds were deemed inactive at the test concentrations. 相似文献
254.
Mohamed Omar Yosuke Matsuo Hajime Maeda Yoshinori Saito Takashi Tanaka 《Phytochemistry letters》2013,6(3):486-490
Two novel glycosides, 4,5-dimethoxy-3-hydroxyphenol 1-O-β-(6′-O-galloyl)-glucopyranoside (1) and (+)-2α-O-galloyl lyoniresinol 3α-O-β-d-xylopyranoside (2), as well as a novel ellagitannin named epiquisqualin B (3), were isolated from sapwood of Quercus mongolica var. crispula along with 19 known phenolic compounds. The structures of the novel compounds were elucidated on the basis of chemical and spectroscopic investigation. Compound 2 is the first example of a lignan galloyl ester, and 3 is the oxidation product of vescalagin, which is the major ellagitannin of this plant. 相似文献
255.
256.
This research highlights the chemical composition, antioxidant and antibacterial activities of essential oils and various crude extracts (using methanol and methylene chloride) from Syzygium cumini leaves. Essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS).The abundant constituents of the oils were: α-pinene (32.32%), β-pinene (12.44%), trans-caryophyllene (11.19%), 1, 3, 6-octatriene (8.41%), delta-3-carene (5.55%), α-caryophyllene (4.36%), and α-limonene (3.42%).The antioxidant activities of all extracts were examined using two complementary methods, namely diphenylpicrylhydrazyl (DPPH) and ferric reducing power (FRAP). In both methods, the methanol extract exhibited a higher activity than methylene chloride and essential oil extracts. A higher content of both total phenolics and flavonoids were found in the methanolic extract compared with other extracts. Furthermore, the methanol extract had higher antibacterial activity compared to methylene chloride and the essential oil extracts. Due to their antioxidant and antibacterial properties, the leaf extracts from S. cumini may be used as natural preservative ingredients in food and/or pharmaceutical industries. 相似文献
257.
Franciszek Burdan Agnieszka Mocarska Marzena Janczarek Robert Klepacz Marek ?osicki Krzysztof Patyra Agnieszka Brodzik Joanna Kiszka Aneta Chru?cicka Iwonna ?elzowska-Cie?lińska El?bieta Staros?awska 《PloS one》2013,8(8)
The spinal perineurial cyst (Tarlov) is a dilatation between the perineurium and endoneurium of spinal nerve roots, located at level of the spinal ganglion and filled with cerebrospinal fluid but without communication with the perineurial subarachnoid space. The aim of the study was to evaluate it incidence among East-European patients. The retrospective data collected during various magnetic resonance spinal examinations and stored on the picture archiving and communication system was analyzed for an incidence of perineurial cysts. From among 842 patients that underwent examination, 75 cases perineurial cysts were revealed. In 22 cases single anomalies were found. In remaining 53 cases, multiple uni- or less frequently bilateral changes were noted. The most common position was the sacral canal, particularly the level of S2 and S3. Occasionally, cysts were also visible on the cervical, thoracic and lumbar level. Incidence of sacral perineurial cysts was significantly higher in females than in males. Similar data was found for single and multiple changes despite of their localization. Insignificant changes were seen for patient age and cyst size. Perineurial spinal cysts were the most frequently observed on the sacral level and such changes were more common in females. 相似文献
258.
Mona H. Soliman Taghreed S. Alnusaire Nessreen F. Abdelbaky Aisha A. M. Alayafi Mirza Hasanuzzaman Mohamed M. Rowezak Mohamed El-Esawi Amr Elkelish 《Phyton》2020,89(3):473-486
Salt stress is one of the major abiotic stress in plants. However,
traditional approaches are not always efficient in conferring salt tolerance. Experiments were conducted to understand the role of Trichoderma spp. (T. harzianum
and T. viride) in growth, chlorophyll (Chl) synthesis, and proline accumulation of
C. pepo exposed to salinity stress. There were three salt stress (50, 100, and
150 mM NaCl) lavels and three different Trichoderma inoculation viz. T. harzianum, T. viride, and T. harzianum + T. viride. Salt stress significantly declined the
growth in terms of the shoot and root lengths; however, it was improved by the
inoculation of Trichoderma spp. C. pepo inoculated with Trichoderma exhibited
increased synthesis of pigments like chl a, chl b, carotenoids, and anthocyanins
under normal conditions. It was interesting to observe that such positive effects
were maintained under salt-stressed conditions, as reflected by the amelioration
of the salinity-mediated decline in growth, physiology and antioxidant defense.
The inoculation of Trichoderma spp. enhanced the synthesis of proline, glutathione, proteins and increased the relative water content. In addition, Trichoderma
inoculation increased membrane stability and reduced the generation of hydrogen peroxide. Therefore, Trichoderma spp. can be exploited either individually
or in combination to enhance the growth and physiology of C. pepo under saline
conditions. 相似文献
259.
Badar Jahan Mohamed F. AlAjmi Md Tabish Rehman Nafees A. Khan 《Physiologia plantarum》2020,168(2):490-510
Nitric oxide (NO) is a hormone that connects numerous reactions in plant cells under normal and environmental stress conditions. The application of 100 µM NO as sodium nitroprusside (SNP; NO donor) applied individually or in combination with N or S in different combinations (i.e. 100 mg N or S kg−1 soil applied at the time of sowing [100 N + 100S]0d or with split, 50 mg N or S kg−1 soil at the time of sowing and similar dose at 20 d after sowing [50 N + 50S]0d + [50 N + 50S]20d) was tested to alleviate salt stress in mustard (Brassica juncea L.). Application of 100 µM NO plus split application of N and S more significantly promoted stomatal behavior, photosynthetic and growth performance in the absence of salt stress and maximally alleviated effects of salt stress through increased N- and S-use efficiency, proline and antioxidant system. The combined application of N and S at the time of sowing was lesser effective in promoting photosynthesis and growth under salt or no salt stress conditions in presence or absence of NO. The study suggests that salt stress effects on the photosynthetic performance are mitigated more efficiently when NO was applied together with the split application of N and S given at two stages, and the photosynthetic activity was promoted under salt stress through increased N and S assimilation and antioxidant system. This strategy may be adopted in agricultural system for overcoming salt stress effects on performance of mustard. 相似文献
260.
Yasmeen S. El Ansari Cynthia Kanagaratham Hans C. Oettgen 《The Yale journal of biology and medicine》2020,93(5):711
Mast cells are a critical first line of defense against endogenous and environmental threats. Their participation in innate immunity is well characterized; activation of toll like receptors as well as receptors for complement, adenosine, and a host of other ligands leads to mast cell release of preformed mediators contained within granules along with newly synthesized arachidonic acid metabolites, cytokines, and chemokines. These confer protective effects including the induction of mucus secretion, smooth muscle contraction, and activation of common itch and pain sensations, all of which act to promote expulsion of noxious agents. While their innate immune role as sentinel cells is well established, recent research has brought into focus their separate but also critical function in adaptive immunity particularly in the setting of IgE mediated food allergies. Crosslinking of FcεR1, the high affinity receptor for IgE, when bound to IgE and antigen, triggers the release of the same factors and elicits the same physiologic responses that occur after activation by innate stimuli. Though IgE-activated mast cells are best known for their role in acute allergic reactions, including the most severe manifestation, anaphylaxis, accumulating evidence has suggested an immunoregulatory effect in T cell-mediated immunity, modulating the balance between type 2 immunity and tolerance. In this review, we outline how mast cells act as adjuvants for food antigen driven Th2 cell responses, while curtailing Treg function. 相似文献