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2.
Iwona Gisterek Ewelina Lata Agnieszka Halon Rafal Matkowski Jolanta Szelachowska Przemyslaw Biecek Jan Kornafel 《Reports of Practical Oncology and Radiotherapy》2011,16(5):173-177
Background
Hepatocyte growth factor plays an important role in tumor growth, metastasis and angiogenesis. C-met is HGF''s high affinity receptor.Aim
The aim of the study was to assess the correlations between c-met expression and clinic-pathological factors in breast cancer tissues. Furthermore, the purpose of the study was to evaluate the prognostic value of the hepatocyte growth factor receptor (HGFR, c-met) expressions in homogenous group of breast cancer patients.Materials and methods
Tumor samples were collected from 302 patients with breast carcinoma treated with primary surgery. We have assessed the percentage of tumor cells with c-met expression, the intensity of reaction and the ratio of these two factors—immunoreactivity according to the Remmele score.Results
We have observed no correlations between HGFR immunoreactivities and clinical parameters (tumor size, grade, axillary lymph node status, age). In 5-year observation we have found prognostic value of assessing c-met immunoreactivity in primary tumor.Conclusion
Our study has revealed prognostic value of c-met. Unlike in other authors’ studies, our patients’ group is very homogenous which might contribute to obtained results. 相似文献3.
Karakulska J Fijałkowski K Nawrotek P Pobucewicz A Poszumski F Czernomysy-Furowicz D 《Journal of microbiology (Seoul, Korea)》2012,50(3):444-451
The aim of this study was an analysis of the staphylococcal flora of the nasal cavity of 42 healthy horses from 4 farms, along with species identification of CoNS isolates and determination of resistance to 18 antimicrobial agents, particularly phenotypic and genotypic methicillin resistance. From the 81 swabs, 87 staphylococci were isolated. All isolates possessed the gap gene but the coa gene was not detected in any of these isolates. Using PCR-RFLP of the gap gene, 82.8% of CoNS were identified: S. equorum (14.9%), S. warneri (14.9%), S. sciuri (12.6%), S. vitulinus (12.6%), S. xylosus (11.5%), S. felis (5.7%), S. haemolyticus (3.4%), S. simulans (3.4%), S. capitis (1.1%), S. chromogenes (1.1%), and S. cohnii subsp. urealyticus (1.1%). To our knowledge, this was the first isolation of S. felis from a horse. The species identity of the remaining Staphylococcus spp. isolates (17.2%) could not be determined from the gap gene PCR-RFLP analysis and 16S rRNA gene sequencing data. Based on 16S-23S intergenic transcribed spacer PCR, 11 different ITS-PCR profiles were identified for the 87 analyzed isolates. Results of API Staph were consistent with molecular identification of 17 (19.5%) isolates. Resistance was detected to only 1 or 2 of the 18 antimicrobial agents tested in the 17.2% CoNS isolates, including 6.9% MRCoNS. The mecA gene was detected in each of the 5 (5.7%) phenotypically cefoxitin-resistant isolates and in 12 (13.8%) isolates susceptible to cefoxitin. In total, from 12 horses (28.6%), 17 (19.5%) MRCoNS were isolated. The highest percentage of MRCoNS was noted among S. sciuri isolates (100%). 相似文献
4.
Jolanta Patamsytė Vytautas Rančelis Tatjana Čėsnienė Violeta Kleizaitė Virginija Tunaitienė Donatas Naugžemys Virginija Vaitkūnienė Donatas Žvingila 《Central European Journal of Biology》2013,8(9):898-911
The alien species Erigeron annuus (L.) Pers. is in an intensive spreading phase in Lithuania. Random amplified polymorphic DNA (RAPDs) and inter-simple sequence repeats (ISSRs) assays were used to study the genetic structure of old and new invasive populations and to determine the most spread genotypes of this species in Lithuania. Pairwise genetic distances between populations established using RAPD and ISSR markers significantly correlated (r=0.91, P<0.05). Our study indicates that there are two genetically different types of E. annuus populations. The first type is represented by a widely spread main clone and related monomorphic populations. The second type is represented by polymorphic populations, some of them present at sites where E. annuus has not been previously observed. Main clone predominates in nine populations and is from the region where this species was first described in natural ecosystems of Lithuania. UPGMA cluster analysis revealed genetic relationships between the main clone and accessions from old cemeteries where E. annuus has been grown as an ornamental plant. We found high genetic differentiation among populations (G ST=0.58 for RAPDs, G ST=0.64 for ISSRs). Taken together, our results will contribute to the monitoring of E. annuus spread in Lithuania. 相似文献
5.
Igor O. Fritsky Jolanta ?wi?tek-Koz?owska Agnieszka Dobosz Nikolay M. Dudarenko 《Inorganica chimica acta》2004,357(12):3746-3752
The formation of the molecular assemblies consisting of anionic and cationic molecules may lead to their interesting structural properties. In this work, we present three new structures based on the tetradentate oxime and amide open-chain ligand CH3-C(NOH)-C(O)-NH-(CH2)3-NH-C(O)-C(NOH)-CH3 (PAP). All the structures contain the complex cations, complex anions [M(PAP-3H)]− and solvating water molecules. These are H-bonded complex anions: [Ni(1,3-pn)2(H2O)2][Ni(PAP-3H)]2 · 4 H2O (1), [Ni(Im)4(H2O)2][Ni(PAP-3H)]2 (2) and [Cu(Im)4(H2O)2][Cu(PAP-3H)]2 · 2H2O (3) (Im=imidazole; 1-3-pn=1,3-diaminopropane). All compounds were synthesised by co-crystallisation of octahedral amine-containing cationic complex with oxime-containing anionic complexes in methanol solution. They were compared with some earlier reported assemblies based on the same ligand (PAP). The comparison of the structures reveals one distinct difference in the separation between the cis-situated oximate oxygen atoms O(1)?O(4) in the copper complexes. The consequence of this effect is the lengthening of the Cu-N distances. In the nickel complexes containing [Ni(PAP-3H)]− anion this effect is much less pronounced. 相似文献
6.
Staphylokinase is a 135 amino acid protein produced by certain strains of Staphylococcus aureus. It belongs to fibrin-specific plasminogen activator. Staphylokinase converts plasminogen--the inactive proenzyme--to the plasmin, which dissolves the fibrin of a blood clots. This review will focus on the biochemical and thrombolytic properties of staphylokinase and its derivatives, which would make use of treatment in acute myocardial infarction and other cardiovascular diseases. 相似文献
7.
The cucumber cotyledon expansion test was used as a model system to study a possible relationship between cytokinin and polyamines.
When kinetin was applied to excised cotyledons incubated in the dark it caused a marked increase in the activity of arginine
decarboxylase. As a result of ADC action, putrescine content also rose markedly, whereas the level of spermidine and spermine
decreased. However, inhibition of putrescine biosynthesis with D-arginine did not affect cytokinin promotion growth. Applied
alone, putrescine had no significant effect on growth. These results indicate that the large increase in putrescine content
that derives from cytokinin treatment cotyledons is not essential for cytokinin-induced expansion of cotyledons. Addition
of K+ and Ca2+ ions to the cotyledons incubated with cytokinin caused a marked reduction in the putrescine level and ADC activity.
The higher level of putrescine (35 %) and spermine (62 %) bound to chromatin and the large increase (174 %) in spermidine
content bound to ribosomes which derive from cytokinintreated cotyledons in relation to literature data can indicate that
these polyamines may play an important role in gene expression during cytokinin-stimulated expansion of cucumber cotyledons.
The inhibition of cytokinin effect, viz. enlargement of the cotyledons by inhibitors of spermidine biosynthesis, additionally suggessted a possible involvement of
polyamines in cytokinin action. 相似文献
8.
E. Hać J. Krechniak M. Szyszko M. Krzyżanowski 《Biological trace element research》2003,92(3):213-219
The aim of this study was to (1) determine the selenium concentration in the renal cortex, liver, and hair in 64 residents
from northern Poland (Gdańsk region) aged 17–81 yr, who died suddenly, and (2) assess whether a correlation between the selenium
concentration in hair and in the renal cortex and liver occurs. Selenium was determined by atomic absorption spectrometry
using the hydride generation method. The mean selenium concentration in the renal cortex, liver, and hair in the investigated
persons was 0.791±0.191 μg/g (wet weight), 0.289±0.084 μg/g (wet weight), and 0.443±0.128 μg/g, respectively. No age-dependent
differences in selenium level in the investigated tissues was found. Also, no correlation between the selenium concentrations
in hair and in renal cortex and liver was assessed. 相似文献
9.
Krzysztof Dziewiszek Raymond F. Schinazi Ting-Chao Chou Tsann-Long Su Jolanta M. Dzik Wojciech Rode 《Nucleosides, nucleotides & nucleic acids》2013,32(1-3):77-94
Abstract A number of 1-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)uracil and -cytosine nucleosides substituted at the 5 position with a nitrophenyl or nitrobenzyl group were synthesized from 5-phenyl- and 5-benzyluracil via condensation of the fluorinated sugar, followed by nitration. The corresponding amino analogues were also prepared by reduction of the nitro nucleosides. The uracil nucleosides were converted into the corresponding cytosine nucleosides by way of the triazole intermediates. None of these nucleosides exhibited significant activity against herpes simplex virus type 1 in Vero cells. However, cytosine nucleosides containing the o-nitrophenyl, p-nitrophenyl, p-nitrobenzyl or p-aminobenzyl substituent were found to be toxic (even at 1 μM) to uninfected Vero cells, although they were essentially nontoxic in HL-60 cells. The 5′-monophosphates of the uracil nucleosides were inhibitors of the reaction catalyzed by purified Ehrlich ascites carcinoma thymidylate synthase, the 5-phenyluracil nucleotides causing a strong inhibition, competitive vs dUMP, described by the Ki value of 0.01 μM. 相似文献
10.
Jolanta Biesaga-Kocielniak Janusz Kocielniak Maria Filek Anna Janeczko 《Plant Cell, Tissue and Organ Culture》2008,94(2):139-147
The aim of this study was to produce suspension cultures of winter wheat directly from immature embryos bypassing the callus
stage, and to determine their capacity for growth and regeneration in comparison to suspension cultures produced from callus.
The study was carried out using Polish winter wheat varieties: ‘Grana’ and ‘Rosa’. Immature embryos were isolated, homogenized
and transferred directly to liquid medium supplemented with 2,4-D. Actively dividing cell cultures were obtained within 2 months
after the cultures were started. Suspension cultures from callus of immature embryos was also produced. With both cultivars,
faster growth was observed in the suspension cultures produced directly from embryos than in the suspensions produced from
callus. Metabolic activity was higher in the suspension culture produced directly from embryos than in the suspension derived
from callus only in ‘Grana’. The production of 1-amiocyclopropane-1-carboxylic acid (ACC), an ethylene precursor, was lower
in the suspension cultures produced directly from embryos than in the suspensions produced from callus. Morphogenic capacity
was significantly higher in aggregates derived directly from embryos than in aggregates derived from callus. With ‘Rosa’,
about one third of the aggregates derived directly from embryos regenerated shoots. Production of ACC was lower in ‘Rosa’
cell culture that regenerated then in other cell cultures that did not. Photosystem II reactions were more efficient in dark
green aggregates than in light green or pale green aggregates which were unable to regenerate. With the method presented,
wheat cell suspension cultures with a regeneration potential can be produced in 2 or 3 months less time than with traditional
methods. 相似文献