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排序方式: 共有552条查询结果,搜索用时 15 毫秒
91.
Halise Inci Gul Parham Taslimi Ilhami Gulcin Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):189-192
4-(3-(4-Substituted-phenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl) benzenesulfonamides (9–16) were successfully synthesized and their chemical structures were confirmed by 1H NMR, 13C NMR, and HRMS spectra. Carbonic anhydrase I and II inhibitory effects of the compounds were investigated. Ki values of the compounds were in the range of 316.7?±?9.6–533.1?±?187.8?nM towards hCA I and 412.5?±?115.4–624.6?±?168.2?nM towards hCA II isoenzymes. While Ki values of the reference compound Acetazolamide were 278.8?±?44.3?nM and 293.4?±?46.4?nM towards hCA I and hCA II izoenzymes, respectively. Compound 14 with bromine and compound 13 with fluorine substituents can be considered as the leader compounds of the series because of the lowest Ki values in series to make further detailed carbonic anhydrase inhibiton studies. 相似文献
92.
İlhami Gulçin Malahat Abbasova Parham Taslimi Zübeyir Huyut Leyla Safarova Afsun Sujayev 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):1174-1182
Compounds containing nitrogen and sulfur atoms can be widely used in various fields such as industry, medicine, biotechnology and chemical technology. Therefore, the reactions of aminomethylation and alkoxymethylation of mercaptobenzothiazole, mercaptobenzoxazole and 2-aminothiazole were developed. Additionally, the alkoxymethyl derivatives of mercaptobenzoxazole and 2-aminothiazole were synthesized by a reaction with hemiformals, which are prepared by the reaction of alcohols and formaldehyde. In this study, the inhibitory effects of these molecules were investigated against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) enzymes and carbonic anhydrase I, and II isoenzymes (hCA I and II). Both hCA isoenzymes were significantly inhibited by the recently synthesized molecules, with Ki values in the range of 58–157?nM for hCA I, and 81–215?nM for hCA II. Additionally, the Ki parameters of these molecules for BChE and AChE were calculated in the ranges 23–88 and 18–78?nM, respectively. 相似文献
93.
94.
Human killer cell immunoglobulin-like receptors (KIR) recognize A3/11, Bw4, C1, and C2 epitopes carried by mutually exclusive
subsets of human leukocyte antigen (HLA)-A, -B, and -C allotypes. Chimpanzee and orangutan have counterparts to HLA-A, -B,
and -C, and KIR that recognize the A3/11, Bw4, C1, and C2 epitopes, either individually or in combination. Because rhesus
macaque has counterparts of HLA-A and -B, but not HLA-C, we expected that rhesus KIR would better recognize HLA-A and -B,
than HLA-C. Comparison of the interactions of nine rhesus KIR3D with 95 HLA isoforms, showed the KIR have broad specificity
for HLA-A, -B, and -C, but vary in avidity. Considering both the strength and breadth of reaction, HLA-C was the major target
for rhesus KIR, followed by HLA-B, then HLA-A. Strong reactions with HLA-A were restricted to the minority of allotypes carrying
the Bw4 epitope, whereas strong reactions with HLA-B partitioned between allotypes having and lacking Bw4. Contrasting to
HLA-A and -B, every HLA-C allotype bound to the nine rhesus KIR. Sequence comparison of high- and low-binding HLA allotypes
revealed the importance of polymorphism in the helix of the α1 domain and the peptide-binding pockets. At peptide position 9, nonpolar residues favor binding to rhesus KIR, whereas charged
residues do not. Contrary to expectation, rhesus KIR bind more effectively to HLA-C, than to HLA-A and -B. This property is
consistent with major histocompatibility complex (MHC)-C having evolved in hominids to be a generally superior ligand for
KIR than MHC-A and MHC-B. 相似文献
95.
Minoo P Chughtai N Campiglio M Stein-Gerlach M Lebrun JJ Ullrich A Ali S 《Cellular signalling》2003,15(3):319-326
SHP-2, a cytosolic protein tyrosine phosphatase with two SH2 domains and multiple tyrosine phosphorylation sites, contributes to signal transduction as an enzyme and/or adaptor molecule. Here we demonstrate that prolactin (PRL) stimulation of the PRL-responsive Nb2 cells, a rat lymphoma cell line, and T47D cells, a human breast cancer cell line, lead to the complex formation of SHP-2 and growth factor receptor-bound protein-2 (grb2). Using transient co-overexpression studies of the prolactin receptor (PRLR) and several tyrosine to phenylalanine mutants of SHP-2, we show that grb2 associates with SHP-2 through the C-terminal tyrosine residues of SHP-2, Y(546) and Y(584). Furthermore, in this study, we found a highly phosphorylated, 29-kDa protein (p29), a substrate of SHP-2. The recruitment of p29 to SHP-2 requires the carboxy-terminal tyrosine residues of SHP-2 (Y(546) and Y(584)). Together, our results indicate that SHP-2 may function as an adaptor molecule downstream of the PRLR and highlight a new recruitment mechanism of SHP-2 substrates. 相似文献
96.
97.
Lucyna Leda Dieter Korn Abbas Ghaderi Vachik Hairapetian Ulrich Struck Wolf Uwe Reimold 《Facies》2014,60(1):295-325
Permian–Triassic boundary sections in the Julfa (NW Iran) and Abadeh (Central Iran) regions display a succession of three characteristic rock units, (1) the Paratirolites Limestone with the mass extinction horizon at its top, (2) the ‘Boundary Clay’, and (3) the earliest Triassic Elikah Formation with the conodont P–Tr boundary at its base. The carbonate microfacies reveals a facies change, in the sections near Julfa, within the Paratirolites Limestone with an increasing number of intraclasts, Fe–Mn crusts, and biogenic encrustation. A decline in carbonate accumulation occurs towards the top of the unit with a sponge packstone in the sections, and finally resulting in a complete demise of the carbonate factory. The succession of the ‘Boundary Clay’ differs in the two regions; thin horizons of sponge packstone are present in the Julfa region and ‘calcite fans’ of probably inorganic origin in the Abadeh Region. The skeletal carbonate factory of the Late Permian was restored with the deposition of microbial carbonates at the base of the Elikah Formation, where densely laminated bindstone, floatstone with sparry calcite spheres, and oncoid wackestone/floatstone predominate. 相似文献
98.
99.
Maria Sole Cigoli Francesca Avemaria Stefano De Benedetti Giovanni P. Gesu Lucio Giordano Accorsi Stefano Parmigiani Maria Franca Corona Valeria Capra Andrea Mosca Simona Giovannini Francesca Notturno Fausta Ciccocioppo Lilia Volpi Margherita Estienne Giuseppe De Michele Antonella Antenora Leda Bilo Antonietta Tavoni Nelia Zamponi Enrico Alfei Giovanni Baranello Daria Riva Silvana Penco 《PloS one》2014,9(10)
Cerebral cavernous malformations (CCMs) are vascular abnormalities that may cause seizures, intracerebral haemorrhages, and focal neurological deficits. Familial form shows an autosomal dominant pattern of inheritance with incomplete penetrance and variable clinical expression. Three genes have been identified causing familial CCM: KRIT1/CCM1, MGC4607/CCM2, and PDCD10/CCM3. Aim of this study is to report additional PDCD10/CCM3 families poorly described so far which account for 10-15% of hereditary cerebral cavernous malformations. Our group investigated 87 consecutive Italian affected individuals (i.e. positive Magnetic Resonance Imaging) with multiple/familial CCM through direct sequencing and Multiplex Ligation-Dependent Probe Amplification (MLPA) analysis. We identified mutations in over 97.7% of cases, and PDCD10/CCM3 accounts for 13.1%. PDCD10/CCM3 molecular screening revealed four already known mutations and four novel ones. The mutated patients show an earlier onset of clinical manifestations as compared to CCM1/CCM2 mutated patients. The study of further families carrying mutations in PDCD10/CCM3 may help define a possible correlation between genotype and phenotype; an accurate clinical follow up of the subjects would help define more precisely whether mutations in PDCD10/CCM3 lead to a characteristic phenotype. 相似文献
100.
Leda Coltro Anna Mourad Paula Oliveira Jose Baddini Rojane Kletecke 《The International Journal of Life Cycle Assessment》2006,11(1):16-21