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121.
Lucero A. Ramón‐Luing Francisco J. Rendón‐Gandarilla Rosa E. Cárdenas‐Guerra Norma A. Rodríguez‐Cabrera Jaime Ortega‐López Leticia Avila‐González Claudia Angel‐Ortiz Carmen N. Herrera‐Sánchez Manuela Mendoza‐García Rossana Arroyo 《Proteomics》2010,10(3):435-444
Trichomonas vaginalis, a sexually transmitted parasite, has many cysteine proteinases (CPs); some are involved in trichomonal pathogenesis, express during infection, and antibodies against CPs have been detected in patient sera. The goal of this study was to identify the antigenic proteinases of T. vaginalis as potential biomarkers for trichomonosis. The proteases detected when T. vaginalis protein extracts are incubated without protease inhibitors, the trichomonad‐active degradome, and the immunoproteome were obtained by using 2‐DE, 2‐D‐zymograms, 2‐D‐Western blot (WB) assays with trichomonosis patient sera, and MS analysis. Forty‐nine silver‐stained spots were detected in the region of 200–21 kDa of parasite protease‐resistant extracts. A similar proteolytic pattern was observed in the 2‐D zymograms. Nine CPs were identified in the 30 kDa region (TvCP1, TvCP2, TvCP3, TvCP4, TvCP4‐like, TvCP12, TvCPT, TvLEGU‐1, and another legumain‐like CP). The major reactive spots to T. vaginalis‐positive patient sera by 2‐D‐WB corresponded to four papain‐like (TvCP2, TvCP4, TvCP4‐like, TvCPT), and one legumain‐like (TvLEGU‐1) CPs. The genes of TvCP4, TvCPT, and TvLEGU‐1 were cloned, sequenced, and expressed in Escherichia coli. Purified recombinant CPs were recognized by culture‐positive patient sera in 1‐D‐WB assays. These data show that some CPs could be potential biomarkers for serodiagnosis of trichomonosis. 相似文献
122.
Carlos Nores Fernando Ballesteros Juan C. Blanco Alicia García-Serrano Juan Herrero Guillermo Palomero 《Acta theriologica》2010,55(3):203-209
Evidence of non-hibernation in brown bears Ursus arctos Linnaeus, 1758 on the Iberian Peninsula has existed since the Middle
Ages. We systematically monitored brown bears in the Cantabrian Mountains (Northern Spain) by recording tracks and sightings
from 1998 to 2007 to document hibernation behaviour. Our results indicate that females with yearlings and solitary yearlings
were more active in winter than bears over two years old. Intensive snow tracking and direct observations of five family groups
indicated that they travelled, fed and defecated in winter, which are activities not compatible with the physiological state
of hibernation. Also, based on tracking data, the maximum period between two consecutive locations of active family groups
in winter was less than that needed by bears to emerge from a state of hibernation (6 days). We conclude that the family groups
which we monitored in winter did not hibernate. 相似文献
123.
Monsalve-Castillo F Chacín-Bonilla L Atencio RJ Espinoza LP Costa-León L Echevarría JM 《Memórias do Instituto Oswaldo Cruz》2007,102(1):107-110
Previous studies have not found hepatitis C virus (HCV) infection in Amerindians from Western Venezuela. A survey of 254 Bari and Yukpa natives aged 10-60 years (mean +/- SD age = 35 +/- 5.4 years) from four communities, two Bari and two Yukpa, in this area were studied to assess the prevalence of antibodies to HCV (anti-HCV) and HCV RNA among these indigenous populations. Serum samples were examined initially for anti-HCV by a four generation enzyme-linked immunosorbent assay (ELISA). Reactive samples were then tested using a third generation recombinant immunoblot assay (RIBA-3). Viral RNA was investigated in all immunoblot-reactive samples by a nested polymerase chain reaction (PCR) method. Six (2.3%) of 254 natives were positive by ELISA, one (2.2%) of these reactive samples were positive by RIBA, and four (1.5%) were indeterminate. Only two (0.8%) were positive by PCR, corresponding to 1 (2.1%) of 47 inhabitants of a Yukpa community and to 1 (2.2%) of 45 subjects of a Bari community. Iatrogenic is thought to play a role in acquisition of the infection. The findings indicate a HCV focus of low endemicity and are compatible with a low degree of exposures of the natives to the virus. Studies are necessary to assess the risk factors for infection in these Amerindians. 相似文献
124.
125.
Quiroga AG Cubo L de Blas E Aller P Navarro-Ranninger C 《Journal of inorganic biochemistry》2007,101(1):104-110
In an attempt to design new antitumoral drugs based on transplatin complexes, we determined the experimental conditions for the preparation of trans-[Pt((CH(3))(2)CNOH)((CH(3))(2)CHNH(2))Cl(2)], and solved the crystal structure. The cytotoxicity of the novel complex, the cis counterpart, cisplatin, and a trans complex with aliphatic amines, as well as the capacity of some of these complexes to cause either apoptotic or necrotic cell death, was comparatively examined in NRK-52E rat renal tubular cells and HepG2 human hepatoma cells. The results indicate that the oxime complex with trans geometry, but not the one with cis geometry, causes death by apoptosis, making the complex potentially suitable for therapeutic purposes. However cytotoxicity values are higher in the case of cis geometry than in trans geometry in both tumoral and non-tumoral cell lines. 相似文献
126.
Herrero MJ Martínez FJ Míguez JM Madrid JA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2007,177(3):319-326
Melatonin is an effective antioxidant, immunostimulant, gonadal maturating regulator and antistress indoleamine that may be
potentially useful for fish farmers. We have explored two possible ways of increasing plasma melatonin levels through the
diet: direct melatonin supplementation (ME diet) and supplementation with the melatonin precursor tryptophan (TRP diet). To
this end, a group of sea bass was fed a commercial diet (STD diet) at a regular time for 16 days, after which plasma, intestine,
and bile samples were taken at four different time points: 120 min before, and 15, 180 and 480 min after feeding. Locomotor
activity, intestinal and biliary melatonin, and plasma melatonin, serotonin and cortisol levels were measured. This same sampling
process and analyses were also carried out after feeding sea bass TRP diet or ME diet for 1 week. Our results show that melatonin,
but not tryptophan supplementation of the diet increases plasma, intestine and bile levels of melatonin. Plasma serotonin
levels, on the other hand, were increased by dietary tryptophan, but not by melatonin, confirming the availability of supplemented
tryptophan for serotonin synthesis. Both treatments were equally effective in reducing the high cortisol levels observed with
the STD diet. 相似文献
127.
Cytosolic activation of cathepsins mediates parvovirus H-1-induced killing of cisplatin and TRAIL-resistant glioma cells
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Di Piazza M Mader C Geletneky K Herrero Y Calle M Weber E Schlehofer J Deleu L Rommelaere J 《Journal of virology》2007,81(8):4186-4198
Gliomas are often resistant to the induction of apoptotic cell death as a result of the development of survival mechanisms during astrocyte malignant transformation. In particular, the overexpression of Bcl-2-family members interferes with apoptosis initiation by DNA-damaging agents (e.g., cisplatin) or soluble death ligands (e.g., TRAIL). Using low-passage-number cultures of glioma cells, we have shown that parvovirus H-1 is able to induce death in cells resistant to TRAIL, cisplatin, or both, even when Bcl-2 is overexpressed. Parvovirus H-1 triggers cell death through both the accumulation of lysosomal cathepsins B and L in the cytosol of infected cells and the reduction of the levels of cystatin B and C, two cathepsin inhibitors. The impairment of either of these effects protects glioma cells from the viral lytic effect. In normal human astrocytes, parvovirus H-1 fails to induce a killing mechanism. In vivo, parvovirus H-1 infection of rat glioma cells intracranially implanted into recipient animals triggers cathepsin B activation as well. This report identifies for the first time cellular effectors of the killing activity of parvovirus H-1 against malignant brain cells and opens up a therapeutic approach which circumvents their frequent resistance to other death inducers. 相似文献
128.
Carrillo R León LG Martín T Martín VS Padrón JM 《Bioorganic & medicinal chemistry letters》2007,17(3):780-783
In this study, we synthesized a series of enantiomerically pure (2R,3R)- and (2R,3S)-disubstituted tetrahydropyrans bearing a CH2O spacer group on the side chain at position 2 of the heterocyclic ring. The in vitro antiproliferative activities of the compounds were examined in the human solid tumor cell lines A2780 (ovarian cancer), SW1573 (non-small cell lung cancer), and WiDr (colon cancer). Overall, the results point out the relevance for antiproliferative activity of the distance between the heterocycle and the unsaturated group. 相似文献
129.
León LG Miranda PO Martín VS Padrón JI Padrón JM 《Bioorganic & medicinal chemistry letters》2007,17(11):3087-3090
The Prins reaction was the basis to synthesize functionalized alkyl chlorodihydropyran derivatives. The inexpensive, stable, and environmentally friendly FeCl(3) promotes the cyclization. The method represents an efficient and regioselective manner to obtain in a single step chlorovinyl-TMS oxacycles. The in vitro antiproliferative activities of the compounds were examined in the human solid tumor cell lines A2780 (ovarian cancer), SW1573 (non-small cell lung cancer), and WiDr (colon cancer). Overall, the results show an enhancement in the cytotoxicity exhibited by the new analogs when compared to their parental compounds. 相似文献