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901.
Karla?León-CisnerosEmail author Eunice?M.?Nogueira Rafael?Riosmena-Rodríguez Ana?Isabel?Neto 《Journal of applied phycology》2011,23(3):467-473
The life-cycle of Scinaia interrupta (A.P. de Candolle) M. J. Wynne was investigated in vitro using four irradiance regimes: 4, 8, 12 and 16 μmol photons m−2 s−1. A triphasic heteromorphic life-cycle was observed. Carpospores released by cystocarps of gametophytes collected in the field
developed into filamentous tetrasporophytes, which produced tetrahedral tetrasporangia. Tetrasporangial development was accelerated
under higher irradiance levels. Tetraspores germinated into filamentous protonemal gametophytes, initially identical to the
tetrasporophyte. Filamentous gametophytes developed apical utricles and gave rise directly to the fleshy gametophyte. Further
development of the fleshy gametophyte was not observed at the lowest irradiance regime (4 μmol photons m−2 s−1). The present study reports for the first time the influence of the irradiance regime on the initial tetrasporangial development
and in the development of the fleshy gametophyte, and reinforces the importance of light intensity on Scinaia life-cycle. Production of apical utricles by the filamentous gametophyte is newly reported for the genus. 相似文献
902.
Cerdeira LT Schneider MP Pinto AC de Almeida SS dos Santos AR Barbosa EG Ali A Aburjaile FF de Abreu VA Guimarães LC Soares Sde C Dorella FA Rocha FS Bol E Gomes de Sá PH Lopes TS Barbosa MS Carneiro AR Jucá Ramos RT Coimbra NA Lima AR Barh D Jain N Tiwari S Raja R Zambare V Ghosh P Trost E Tauch A Miyoshi A Azevedo V Silva A 《Journal of bacteriology》2011,193(24):7025-7026
In this work, we report the whole-genome sequence of Corynebacterium pseudotuberculosis bv. equi strain CIP 52.97 (Collection Institut Pasteur), isolated in 1952 from a case of ulcerative lymphangitis in a Kenyan horse, which has evidently caused significant losses to agribusiness. Therefore, obtaining this genome will allow the detection of important targets for postgenomic studies, with the aim of minimizing problems caused by this microorganism. 相似文献
903.
de Torres EM Barbosa GA Bernardes SR de Mattos Mda G Ribeiro RF 《Journal of biomechanics》2011,44(9):1735-1739
An inappropriate prosthetic fit could cause stress over the interface implant/bone. The objective of this study was to compare stresses transmitted to implants from frameworks cast using different materials and to investigate a possible correlation between vertical misfits and these stresses. Fifteen one-piece cast frameworks simulating bars for fixed prosthesis in a model with five implants were fabricated and arranged into three different groups according to the material used for casting: CP Ti (commercially pure titanium), Co-Cr (cobalt-chromium) or Ni-Cr-Ti (nickel-chromium-titanium) alloys. Each framework was installed over the metal model with all screws tightened to a 10 N cm torque and then, vertical misfits were measured using an optical microscope. The stresses transmitted to implants were measured using quantitative photoelastic analysis in values of maximum shear stress (τ), when each framework was tightened to the photoelastic model to a 10 N cm standardized torque. Stress data were statistically analyzed using one-way ANOVA and Tukey's test and correlation tests were performed using Pearson's rank correlation (α = 0.05). Mean and standard deviation values of vertical misfit are presented for CP Ti (22.40 ± 9.05 μm), Co-Cr (66.41 ± 35.47 μm) and Ni-Cr-Ti (32.20 ± 24.47 μm). Stresses generated by Co-Cr alloy (τ = 7.70 ± 2.16 kPa) were significantly higher than those generated by CP Ti (τ = 5.86 ± 1.55 kPa, p = 0.018) and Ni-Cr-Ti alloy (τ = 5.74 ± 3.05 kPa, p = 0.011), which were similar (p = 0.982). Correlations between vertical misfits and stresses around the implants were not significant as for any evaluated materials. 相似文献
904.
Costa FT Lopes SC Ferrer M Leite JA Martin-Jaular L Bernabeu M Nogueira PA Mourão MP Fernandez-Becerra C Lacerda MV del Portillo H 《Memórias do Instituto Oswaldo Cruz》2011,106(Z1):79-84
It is generally accepted that Plasmodium vivax, the most widely distributed human malaria parasite, causes mild disease and that this species does not sequester in the deep capillaries of internal organs. Recent evidence, however, has demonstrated that there is severe disease, sometimes resulting in death, exclusively associated with P. vivax and that P. vivax-infected reticulocytes are able to cytoadhere in vitro to different endothelial cells and placental cryosections. Here, we review the scarce and preliminary data on cytoadherence in P. vivax, reinforcing the importance of this phenomenon in this species and highlighting the avenues that it opens for our understanding of the pathology of this neglected human malaria parasite. 相似文献
905.
Marietto-Gonçalves GA Grandi F 《Memórias do Instituto Oswaldo Cruz》2011,106(6):781; author reply 781-781; author reply 782
906.
Cordeiro Rde A Astete-Medrano DJ Marques FJ Andrade HT Perdigão Neto LV Tavares JL de Lima RA Patoilo KK Monteiro AJ Brilhante RS Rocha MF de Camargo ZP Sidrim JJ 《Memórias do Instituto Oswaldo Cruz》2011,106(8):1045-1048
The aim of the present study was to evaluate the effect of cotrimoxazole on the in vitro susceptibility of Coccidioides posadasii strains to antifungals. A total of 18 strains of C. posadasii isolated in Brazil were evaluated in this study. The assays were performed in accordance with the Clinical and Laboratory Standards Institute guidelines and the combinations were tested using the checkerboard method. The minimum inhibitory concentrations were reduced by 11, 2.4, 4.3 and 3.5 times for amphotericin B, itraconazole, fluconazole and voriconazole, respectively. Moreover, it was seen that cotrimoxazole itself inhibited C. posadasii strains in vitro. The impairment of folic acid synthesis may be a potential antifungal target for C. posadasii. 相似文献
907.
Veronesi MC Panzani S Govoni N Kindahl H Galeati G Robbe D Carluccio A 《Theriogenology》2011,75(4):752-759
The transition from intra- to extrauterine environment represents a very delicate phase, in which the successful coordination of maturation is strictly connected with several hormonal changes during the last weeks of gestation and at parturition. While the peripartal endocrinology in the mare has been deeply investigated, the peripartal hormonal changes in the jenny need further evaluation. The aim of this study is to evaluate the mean 15-ketodihydro-PGF2α (PGFM), cortisol (C), progesterone (P4), and 17β-estradiol (E2) levels during the peripartal period in this species. Ten Martina Franca jennies, with normal gestational length and parturition, were enrolled. From each jenny, blood was collected twice a day from 10 d before to 7 d after parturition and from the plasma obtained PGFM, C, P4 and E2 were analyzed by RIA. Higher, constant PGFM concentrations were observed in the pre-foaling days compared to the decreasing levels detected the days after delivery, as previously observed in the mare. During the whole period of observation no significant differences in plasma C levels were detected. In contrast to the mare, P4 has always been detectable and the highest level found at −2.5 days was significantly different compared to samples obtained between −10 and −4.5 days and between 1.5 and 7 days after foaling. Finally, E2 showed higher concentrations before foaling, with the highest values between −3 and −1.5 days, decreasing only one day before foaling. A positive correlation was found between PGFM and P4, during the last 4 days of gestation, while a positive correlation between PGFM and E2 was observed during the prepartum. Despite some similarities with the mare exist, differences have been found in P4 and E2 profiles, underlining once more the differences in the physiology of this two species. 相似文献
908.
Rossetti RC Perdigão A Mesquita FS Sá Filho M Nogueira GP Machado R Membrive CM Binelli M 《Theriogenology》2011,76(4):751-758
The objective was to compare pharmacological strategies aiming to inhibit prostaglandin F2 alpha (PGF2α) synthesis (flunixin meglumine; FM), stimulate growth of the conceptus (recombinant bovine somatotropin; bST) and progesterone (P4) synthesis (human chorionic gonadotropin; hCG), as well as their combinations, regarding their ability to improve pregnancy rates in beef cattle. Lactating Nelore cows (N = 975), 35 to 70 days postpartum, were synchronized and inseminated by timed artificial insemination (TAI) on Day 0. On Day 7, cattle were allocated into eight groups and received one of the following treatments: saline (S) on Days 7 and 16 (Group Control); S on Day 7 and FM on Day 16 (Group FM); bST on Day 7 and S on Day 16 (Group bST); bST on Day 7 and FM on Day 16 (Group bST + FM); hCG on Day 7 and S on Day 16 (Group hCG); hCG on Day 7 and FM on Day 16 (Group hCG + FM); bST and hCG on Day 7 and S on Day 16 (Group bST + hCG), or bST and hCG on Day 7 and FM on Day 16 (Group bST + hCG + FM). The aforementioned treatments were administered at the following doses: 2.2 mg/kg FM (Banamine®; Intervet Schering-Plough, Cotia, SP, Brazil), 500 mg bST (Boostin®; Intervet Schering-Plough), and 2500 IU hCG (Chorulon®; Intervet Schering-Plough). Pregnancy diagnosis was performed 40 days after TAI by transrectal ultrasonography. Pregnancy rates were not significantly different among treatments. However, there was a main effect of hCG treatment to increase pregnancy rates (63.0 vs. 55.4%; P = 0.001). Concentrations of P4 did not differ significantly among groups on Day 7 or on Day 16. However, consistent with the higher pregnancy rates, hCG increased P4 concentrations on Day 16 (10.6 vs. 9.6 ng/mL, respectively; P = 0.05). We concluded that hCG treatment 7 days after TAI improved pregnancy rates of lactating Nelore cows, possibly via a mechanism leading to induction of higher P4 concentrations, or by reducing the luteolytic stimulus during maternal recognition of pregnancy. 相似文献
909.
Bello ML Chiaradia LD Dias LR Pacheco LK Stumpf TR Mascarello A Steindel M Yunes RA Castro HC Nunes RJ Rodrigues CR 《Bioorganic & medicinal chemistry》2011,19(16):5046-5052
In this work we described the synthesis, the antileishmanial activity and the molecular modeling and structure-activity relationship (SAR) evaluations of a series of chalcone derivatives. Among these compounds, the methoxychalcones 2h, 2i, 2j, 2k and 2l showed significant antileishmanial activity (IC(50)<10 μM). Interestingly 2i (IC(50)=2.7 μM), 2j (IC(50)=3.9 μM) and 2k (IC(50)=4.6 μM) derivatives presented better antileishmanial activity than the control drug pentamidine (IC(50)=6.0 μM). Our SAR study showed the importance of methoxy di-ortho substitution at phenyl ring A and the relationship between the frontier orbital HOMO coefficients distribution of these molecules and their activity. The most active compounds 2h, 2i, 2j, 2k, and 2l fulfilled the Lipinski rule-of-five which theoretically is important for good drug absorption and permeation through biological membranes. The potential profile of 2j (IC(50)=3.9 μM and CC(50)=216 μM) pointed this chalcone derivative as a hit compound to be further explored in antileishmanial drug design. 相似文献
910.
Coelho Cerqueira E Netz PA Diniz C Petry do Canto V Follmer C 《Bioorganic & medicinal chemistry》2011,19(24):7416-7424
Monoamine oxidase (MAO) catalyzes the oxidative deamination of biogenic and exogenous amines and its inhibitors have therapeutic value for several conditions including affective disorders, stroke, neurodegenerative diseases and aging. The discovery of 2,3,6-trimethyl-1,4-naphthoquinone (TMN) as a nonselective and reversible inhibitor of MAO, has suggested 1,4-naphthoquinone (1,4-NQ) as a potential scaffold for designing new MAO inhibitors. Combining molecular modeling tools and biochemical assays we evaluate the kinetic and molecular details of the inhibition of human MAO by 1,4-NQ, comparing it with TMN and menadione. Menadione (2-methyl-1,4-naphthoquinone) is a multitarget drug that acts as a precursor of vitamin K and an inducer of mitochondrial permeability transition. Herein we show that MAO-B was inhibited competitively by 1,4-NQ (Ki = 1.4 μM) whereas MAO-A was inhibited by non-competitive mechanism (Ki = 7.7 μM). Contrasting with TMN and 1,4-NQ, menadione exhibited a 60-fold selectivity for MAO-B (Ki = 0.4 μM) in comparison with MAO-A (Ki = 26 μM), which makes it as selective as rasagiline. Fluorescence and molecular modeling data indicated that these inhibitors interact with the flavin moiety at the active site of the enzyme. Additionally, docking studies suggest the phenyl side groups of Tyr407 and Tyr444 (for MAO-A) or Tyr398 and Tyr435 (for MAO-B) play an important role in the interaction of the enzyme with 1,4-NQ scaffold through forces of dispersion as verified for menadione, TMN and 1,4-NQ. Taken together, our findings reveal the molecular details of MAO inhibition by 1,4-NQ scaffold and show for the first time that menadione acts as a competitive and reversible inhibitor of human MAO. 相似文献