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171.
Grześko J Elias M Maczyńska B Kasprzykowska U Tłaczała M Goluda M 《Medycyna do?wiadczalna i mikrobiologia》2007,59(2):169-175
The group of organisms commonly referred to as genital mycoplasmas comprise species most often found in genitourinary tract of sexually active adults as common commensal inhabitants, or pathogens which can possibly cause many different pathologies like: non-gonococcal urethritis, bacterial vaginosis, cervicitis, endometritis or pelvic inflammatory disease. The problem of their morbidity and the possible influence they have on human fertility is still not clear. The aim of this study was to find out whether two investigated species- Ureaplasma urealyticum and Mycoplasma hominis can be detect more often in a group of infertile women. 74 women participated in the study and were assigned to one of 2 groups of patients: infertile women and fertile women without any sign of genital tract infection. Swabs from the cervical canal of the uterus and the fluid from the Douglas pouch were taken during the gynecological examination and laparoscopic procedure. Two diagnostic methods were used: biochemical method- commercial diagnostic kit- Mycoplasma IST 2 and PCR method. The results showed that Ureaplasma urealyticum and Mycoplasma hominis were detected among both fertile and infertile women with nearly the same frequency, much more often in cervical canal than in the Douglas pouch. Ureaplasma urealyticum was more common pathogen than Mycoplasma hominis in both groups and locations. The achieved results point out that the role of genital mycoplasmas in human infertility is still unclear and require further investigations. 相似文献
172.
Historic emissions from a Ni refinery at Port Colborne, Ontario, caused Ni contamination of regional soils and raised concerns
about potential Ni phytotoxicity. Previous tests revealed that if these soils were made alkaline and fertilized with Mn and
other common nutrients as needed to maintain fertility of such alkaline soils, full remediation (prevention of Ni phytotoxicity)
would be obtained. This experiment was conducted to test this method of remediation on diverse soils from Port Colborne, and
to evaluate chemical extraction tests which would be predictive of plant uptake and potential for Ni phytotoxicity in Ni-contaminated
soils. Ten soils with varied levels of Ni contamination and varied soil properties were amended with limestone or nitric acid
to raise or lower pH so that a wide pH range could be examined for the soils. For lower Ni organic and mineral soils near
the Ontario remediation limit (200 mg/kg), neither crop suffered Ni phytotoxicity at any pH tested. Only when more highly
contaminated soils were strongly acidic did Ni phytotoxicity occur. Phytotoxic soils were fully remediated by making soils
alkaline even for these Ni-sensitive crop species. Only the most contaminated organic soil remained slightly toxic – but this
soil was remarkably contaminated (over 1.1% of Ni). The Sr nitrate extraction method was much more effective in predicting
plant Ni concentrations than the DTPA method. This test provides an inexpensive soil extraction result highly predictive of
potential for Ni phytotoxicity across soils. 相似文献
173.
Coat colour anomalies in the common shrew, Sorex araneus L., in the geographical range of this species, including Poland, are extremely rare. This study describes atypically coloured common shrews. Light colouration of the coat is a result of lack ofpigment in the entire hair or hair fragments. It appears that atypically coloured shrews occur more often in isolated populations whose gene transfer with neighboring populations is limited. 相似文献
174.
Sengupta P Ruano MJ Tebar F Golebiewska U Zaitseva I Enrich C McLaughlin S Villalobo A 《The Journal of biological chemistry》2007,282(11):8474-8486
Membrane-permeable calmodulin inhibitors, such as the napthalenesulfonamide derivatives W-7/W-13, trifluoperazine, and calmidazolium, are used widely to investigate the role of calcium/calmodulin (Ca2+/CaM) in living cells. If two chemically different inhibitors (e.g. W-7 and trifluoperazine) produce similar effects, investigators often assume the effects are due to CaM inhibition. Zeta potential measurements, however, show that these amphipathic weak bases bind to phospholipid vesicles at the same concentrations as they inhibit Ca2+/CaM; this suggests that they also bind to the inner leaflet of the plasma membrane, reducing its negative electrostatic surface potential. This change will cause electrostatically bound clusters of basic residues on peripheral (e.g. Src and K-Ras4B) and integral (e.g. epidermal growth factor receptor (EGFR)) proteins to translocate from the membrane to the cytoplasm. We measured inhibitor-mediated translocation of a simple basic peptide corresponding to the calmodulin-binding juxtamembrane region of the EGFR on model membranes; W-7/W-13 causes translocation of this peptide from membrane to solution, suggesting that caution must be exercised when interpreting the results obtained with these inhibitors in living cells. We present evidence that they exert dual effects on autophosphorylation of EGFR; W-13 inhibits epidermal growth factor-dependent EGFR autophosphorylation under different experimental conditions, but in the absence of epidermal growth factor, W-13 stimulates autophosphorylation of the receptor in four different cell types. Our interpretation is that the former effect is due to W-13 inhibition of Ca2+/CaM, but the latter results could be due to binding of W-13 to the plasma membrane. 相似文献
175.
Agnieszka Gniazdowska Urszula Krasuska Karolina Dębska Paulina Andryka Renata Bogatek 《Planta》2010,232(4):999-1005
Deep dormancy of apple (Malus domestica Borkh.) seeds is terminated by a 3-month-long cold stratification. It is expressed by rapid germination of seeds and undisturbed growth of seedlings. However, stimulation of germination of isolated apple embryos is also observed after applying inhibitors of cytochrome c oxidase: nitric oxide (NO) or hydrogen cyanide (HCN) during the first 3–6 h of imbibition of dormant embryos. The aim of this work was to compare the effect of yet another toxic gaseous molecule carbon monoxide (CO) with the effects of HCN and NO on germination of apple embryos and growth and development of young seedlings. We demonstrated that stimulation of germination after short-term pre-treatment with HCN, NO or CO was accompanied by enhanced NO emission from the embryo axes during their elongation. Moreover, similarly high NO production from non-dormant embryos, after cold stratification, was detected. Therefore, we propose that NO may act as signaling molecule in apple embryo dormancy break. 相似文献
176.
The Effect of Acute Hypoxia on Synaptosomes from Rat Brain 总被引:4,自引:4,他引:4
Abstract: Synaptosomes have been isolated from the brains of nonanesthetized and nembutal-anesthetized rats subjected to 30 min hypoxia induced by breathing 7% oxygen in nitrogen. The respiratory rate was depressed in synaptosomes from starved hypoxic animals but was not significantly different from the respective control values in preparations from fed hypoxic animals, anesthetized animals, and hypoxic nonanesthetized animals allowed to recover from the hypoxic episode by 60 min of normoxic conditions. Observations are also reported concerning the levels of various metabolites in the synaptosomes isolated from the brains of the same groups of animals. It is suggested that hypoxia results in damage to the synaptosomal and/or mitochondrial membrane, which modifies substrate oxidation in the mitochondria and decreases availability of reducing equivalents for the respiratory chain. Results obtained on afflicted and recovered animals indicate that synaptosomal preparations provide a useful model for the study of hypoxic damage. 相似文献
177.
Origin, distribution and 3D-modeling of Gr-EXPB1, an expansin from the potato cyst nematode Globodera rostochiensis 总被引:1,自引:0,他引:1
Kudla U Qin L Milac A Kielak A Maissen C Overmars H Popeijus H Roze E Petrescu A Smant G Bakker J Helder J 《FEBS letters》2005,579(11):2451-2457
Southern analysis showed that Gr-EXPB1, a functional expansin from the potato cyst nematode Globodera rostochiensis, is member of a multigene family, and EST data suggest expansins to be present in other plant parasitic nematodes as well. Homology modeling predicted that Gr-EXPB1 domain 1 (D1) has a flat beta-barrel structure with surface-exposed aromatic rings, whereas the 3D structure of Gr-EXPB1-D2 was remarkably similar to plant expansins. Gr-EXPB1 shows highest sequence similarity to two extracellular proteins from saprophytic soil-inhabiting Actinobacteria, and includes a bacterial type II carbohydrate-binding module. These results support the hypothesis that a number of pathogenicity factors of cyst nematodes is of procaryotic origin and were acquired by horizontal gene transfer. 相似文献
178.
The NADP-dependent isocitrate dehydrogenase obtained from brain cytosol of control and hypoxic animals was purified 36-fold by a combination of chromatography on DE-32 cellulose, CM cellulose, and DEAE-Sephadex and electrophoresis. Hypoxia did not change the molecular weight (about 165,000) of the enzyme, which was composed of two subunits of 80,000 daltons each. 相似文献
179.
180.
Burdzińska A Bartoszuk-Bruzzone U Godlewski MM Orzechowski A 《Comparative medicine》2006,56(6):493-501
Engraftment of muscle-derived cells (MDCs) into the urethral sphincter may cure urinary incontinence. However, poor cell survival after injection prompted us to evaluate whether 24-h preincubation with sodium ascorbate (ASC) or basic fibroblast growth factor (bFGF) prior to cell transfer improves the survival of MDCs facing oxidative stress in vitro. We examined MDCs isolated from female rats for the presence of myogenic markers and for the ability to differentiate and respond to growth factors. Isolated cells were positive for desmin, M-cadherin, and myogenin. The fusion index exceeded 29%, and Akt kinase was phosphorylated at Ser473 residue upon exposure to insulin-like growth factor 1 (100 ng/ml). We then autologously transplanted MDCs transfected with lacZ marker gene into urethral wall of the rats; 2 wk later, the urethra and caudal wall of the urinary bladder were harvested from these animals. Serial cryosections revealed that transplanted cells formed multinuclear clusters at injection sites. In addition, we found that the viability of MDCs exposed to a cytotoxic concentration of H2O2 was higher after preincubation with 0.1 mM ASC (2.6-fold), 10 ng/ml bFGF (2.9-fold), or 20 ng/ml bFGF (3.5-fold) than that after exposure to H2O2 only. We conclude that preincubation with ASC or bFGF increases the resistance of MDCs to oxidative stress in vitro. Pretreatment with either agent might be used to enhance survival of MDCs after transplantation. 相似文献