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611.
Mustafa Kayan Mustafa Nazıroğlu Ömer Çelik Kadir Yalman Halis Köylü 《Cell biochemistry and function》2009,27(7):424-429
X‐ray radiation is detrimental to human cells and may lead to development of life‐threatening diseases. Cigarette smoke contains about 500 chemicals that include organic and oxidant compounds whereas vitamin C and E (VCE) have scavenger effects on the compounds. We investigated effects of VCE administration on X‐ray‐induced oxidative toxicity in blood of smoker and nonsmoker X‐ray technicians. Twenty technicians and 30 healthy age‐matched subjects control were used in the study. Ten of the X‐ray technicians and 15 of the control were smokers. Blood samples were taken from the control. Oral vitamin C (500 mg) and vitamin E (150 mg) were daily supplemented to the smoker and nonsmoker X‐ray technicians for 5 weeks. Blood samples were taken from the X‐ray technicians after and before 5 weeks. Plasma and erythrocytes lipid peroxidation (LP), reduced glutathione (GSH) levels, erythrocytes glutathione peroxidase (GSH‐Px), and plasma antioxidant vitamin concentrations were investigated in control and X‐ray technicians with smoker and nonsmoker. Plasma and erythrocytes LP levels were higher in the total X‐ray group and smoker X‐ray group than in control and nonsmoker X‐ray group, respectively although the LP level was decreased by the VCE treatment. The plasma vitamin C, vitamin A, vitamin E, and β‐carotene concentrations were lower in the X‐ray group than in control although their concentrations were increased by the treatment. The erythrocytes GSH level and GSH‐Px activity were found to be higher in the treatment group than in the X‐ray group. Plasma GSH level was not found to be different in all group. Reactive oxygen species may play role in the mechanism that has been proposed to explain the biological side effect of X‐ray radiation and smoke. VCE prevents the smoke and X‐ray‐induced oxidative stress to strengthen antioxidant vitamin concentrations in the blood of the technicians. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
612.
FranÇois Bourlière 《International journal of primatology》1985,6(1):1-26
The structure of primate communities living in a number of undisturbed areas is described and compared. Species richness is
highest in tropical rain forests of Africa and South America, where up to 14 different species can share the same habitat.
The number of sympatric primates in woodlands and savannas is always much lower. Some striking differences in community structure
may be observed between communities living in apparently similar habitats. Three major factors may be held responsible for
such discrepancies: history and paleoecology, present spatial heterogeneity of the vegetation, and competition with other
taxonomic groups. The role of primates in the functioning of forest ecosystems is discussed. Though their trophic impact may
be important, the role they play in seed dispersal appears to be more significant; they contribute greatly to homeostasis,
as well as to regeneration, of the rain forests. A number of ecological traits are particularly developed among primates and
may have contributed to the rapid evolutionary success of the order. Their predominantly vegetarian diet allows them to build
up higher population densities than sympatric carnivorous mammals;their arborealism permits them to make use of all edible plant material available in a tridimensional environment; the opportunistic
tendencies of some cebids, cercopithecids, and pongids enable them to take advantage of a variety of habitats and situations;
and finally, an extended socialization period and a long life-span, allowing them to develop social traditions, give to many
of them a further possibility to adapt quickly to novel situations.
This paper is a revised version of the third Osman Hill Memorial Lecture delivered at the joint meeting of the Primate Society
of Great Britain and the Association for the Study of Animal Behaviour, held in London on 2/3 December 1982. 相似文献
613.
A. O. Çavdar M. Bahçeci N. Akar F. N. Dinçer J. Erten 《Biological trace element research》1991,30(1):81-85
Hair zinc concentration was measured in samples taken from 57 mothers who delivered infants with neural tube defects (NTD) (mainly anencephaly). Control groups consisted of 30 healthy mothers with normal offspring and 37 nonpregnant women from middle-income backgrounds. Zinc concentration was also measured in the hair of eight infants with NTD (four being anencephalic). The mean maternal hair zinc concentration in the NTD group (128.2 +/- 38.9 micrograms/g) was lower than that of the control women (p less than 0.001), whereas the mean hair zinc level of malformed babies (250.4 +/- 85.2 micrograms/g) was significantly higher than that of normal infants (193.4 +/- 39.2 micrograms/g) (p less than 0.05). Maternal nutritional zinc deficiency was thought to be one of the factors responsible for NTD in Turkey. 相似文献
614.
Effect of vitamin B6 on lenses of diabetic rats 总被引:2,自引:0,他引:2
Yarat A Yanardağ R Ozçelik F Ozsoy O Bapçum A Emekli N 《Indian journal of experimental biology》1998,36(12):1269-1272
Vitamin B6 is essential for the metabolism of fat, carbohydrate and protein. In this study the effect of vitamin B6 on diabetes induced impairments in rat lenses was investigated. Although macroscopic examination revealed no opacification of rat lenses in any groups, uncontrolled induced diabetes caused significant decreases in lens glutathione and increases in lens protein nonenzymatic glycosylation and blood glucose. Administration of vitamin B6 did not inhibit these diabetes induced alterations significantly. SDS-polyacrylamide gel electrophoresis revealed some significant differences in some protein bands between groups. 相似文献
615.
The aim of this work was to determine the protective effects of intraperitoneally administered vitamins C and E and selenium
on the lipid peroxidation (MDA), glutathione peroxidase (GSH-Px), reduced glutathione (rGSH) activities in the lens of rats
induced diabetic with streptozotocin (STZ). Lenses in the diabetic control group had a slightly higher mean level of MDA compared
with lenses of the vitamin E and selenium groups, although the mean levels of MDA were significantly lower in control, combination,
and vitamin C groups than in the diabetic control group (p < 0.05 andp < 0.01). However, MDA levels were significantly lower in vitamin C, vitamin E, and combination groups than in controls (p < 0.01).
The GSH-Px activities of lenses were significantly higher in vitamin C-, vitamin E- and selenium-injected groups than that
in the diabetic control group (p < 0.01), whereas, the activity of GSH-Px was significantly lower in the diabetic control group than in the control group.
In addition, the rGSH content was seen to decrease only in the vitamin C group compared to both control and diabetic control
groups (p < 0.05).
In conclusion, the results from these experiments indicate that vitamins C and E and selenium can protect the lens against
oxidative damage, but the effect of vitamin C appears to be much greater than that of vitamin E and selenium. 相似文献
616.
Sevil Şenkardeş İrem Atlıhan Elif Çayır Pınar Mega Tiber Oya Orun Şeyma Nigiz Ceren Özkul Miyase Gözde Gündüz Ş. Güniz Küçükgüzel 《化学与生物多样性》2023,20(8):e202300766
By exploiting the wide biological potential of the hydrazone scaffold, a series of hydrazone derivatives were synthesized, starting from N-(3-hydroxyphenyl)acetamide (metacetamol). The structures of the compounds were determined using IR, 1H and 13C-NMR, and mass spectroscopic methods. The obtained molecules ( 3 a – j ) were evaluated for their anticancer potential against MDA-MB-231 and MCF-7 breast cancer cell lines. According to the CCK-8 assay, all tested compounds showed moderate to potent anticancer activity. Among them, N-(3-(2-(2-(4-nitrobenzylidene)hydrazinyl)-2-oxoethoxy)phenyl)acetamide ( 3 e ) was found to be the most effective derivative with an IC50 value of 9.89 μM against MDA-MB-231 cell lines. This compound was further tested for its potential effects on the apoptotic pathway. Molecular docking studies was also carried out for 3 e in the colchicine binding pocket of tubulin. Additionally, compound 3 e also demonstrated effective antifungal activity, particularly against Candida krusei (MIC=8 μg/ml), indicating that nitro group at the 4th position of the phenyl ring was the most preferable substituent for both cytotoxic and antimicrobial activity. Our preliminary findings suggest that compound 3 e could be exploited as a leading structure for further anticancer and antifungal drug development. 相似文献
617.
Dr. Halil Şenol Dr. Zeynep Çağman Tuğba Gençoğlu Katmerlikaya Dr. Feyzi Sinan Tokalı 《化学与生物多样性》2023,20(8):e202300773
In this study, twenty new anthranilic acid hydrazones 6 – 9 ( a – e ) were synthesized and their structures were characterized by Fourier-transform Infrared (FT-IR), Nuclear Magnetic Resonance (1H-NMR – 13C-NMR), and High-resolution Mass Spectroscopy (HR-MS). The inhibitory effects of the compounds against COX-II were evaluated. IC50 values of the compounds were found in the range of >200–0.32 μM and compounds 6e , 8d , 8e , 9b , 9c , and 9e were determined to be the most effective inhibitors. Cytotoxic effects of the most potent compounds were investigated against human hepatoblastoma (Hep-G2) and human healthy embryonic kidney (Hek-293) cell lines. Doxorubicin (IC50: 8.68±0.16 μM for Hep-G2, 55.29±0.56 μM for Hek-293) was used as standard. 8e is the most active compound, with low IC50 against Hep-G2 (4.80±0.04 μM), high against Hek-293 (159.30±3.12), and high selectivity (33.15). Finally, molecular docking and dynamics studies were performed to understand ligand-protein interactions between the most potent compounds and COX II, Epidermal Growth Factor Receptor (EGFR), and Transforming Growth Factor beta II (TGF-βII). The docking scores were calculated in the range of −10.609–−6.705 kcal/mol for COX-II, −8.652–−7.743 kcal/mol for EGFR, and −10.708–−8.596 kcal/mol for TGF-βII. 相似文献
618.
Beste Çağdaş Tunalı Eda Çelik Fatma Azize Budak Yıldıran Mustafa Türk 《Biopolymers》2023,114(4):e23535
In this study, effective transport of small interfering RNAs (siRNAs) via hyaluronic acid (HA) receptor was carried out with biodegradable HA and low-molecular weight polyethyleneimine (PEI)-based transport systems. Gold nanoparticles (AuNPs) capable of giving photothermal response, and their conjugates with PEI and HA, were also added to the structure. Thus, a combination of gene silencing, photothermal therapy and chemotherapy, has been accomplished. The synthesized transport systems ranged in size, between 25 and 690 nm. When the particles were applied at a concentration of 100 μg mL−1 (except AuPEI NPs) in vitro, cell viability was above 50%. Applying radiation after the conjugate/siRNA complex (especially those containing AuNP) treatment, increased the cytotoxic effect (decrease in cell viability of 37%, 54%, 13%, and 15% for AuNP, AuPEI NP, AuPEI-HA, and AuPEI-HA-DOX, respectively) on the MDA-MB-231 cell line. CXCR4 gene silencing via the synthesized complexes, especially AuPEI-HA-DOX/siRNA was more efficient in MDA-MB-231 cells (25-fold decrease in gene expression) than in CAPAN-1 cells. All these results demonstrated that the synthesized PEI-HA and AuPEI-HA-DOX conjugates can be used as siRNA carriers that are particularly effective, especially in the treatment of breast cancer. 相似文献
619.
ERIC A. DAVIDSON DANIEL C. NEPSTAD FRANÇOISE YOKO ISHIDA PAULO M. BRANDO 《Global Change Biology》2008,14(11):2582-2590
Changes in precipitation in the Amazon Basin resulting from regional deforestation, global warming, and El Niño events may affect emissions of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and nitric oxide (NO) from soils. Changes in soil emissions of radiatively important gases could have feedback implications for regional and global climate. Here, we report the final results of a 5‐year, large‐scale (1 ha) throughfall exclusion experiment, followed by 1 year of recovery with natural throughfall, conducted in a mature evergreen forest near Santarém, Brazil. The exclusion manipulation lowered annual N2O emissions in four out of five treatment years (a natural drought year being the exception), and then recovered during the first year after the drought treatment stopped. Similarly, consumption of atmospheric CH4 increased under drought treatment, except during a natural drought year, and it also recovered to pretreatment values during the first year that natural throughfall was permitted back on the plot. No treatment effect was detected for NO emissions during the first 3 treatment years, but NO emissions increased in the fourth year under the extremely dry conditions of the exclusion plot during a natural drought. Surprisingly, there was no treatment effect on soil CO2 efflux in any year. The drought treatment provoked significant tree mortality and reduced the allocation of C to stems, but allocation of C to foliage and roots were less affected. Taken together, these results suggest that the dominant effect of throughfall exclusion on soil processes during this 6‐year period was on soil aeration conditions that transiently affected CH4, N2O, and NO production and consumption. 相似文献
620.
Semra Doğru‐Abbasoğlu Hande Parıldar‐Karpuzoğlu Bilge Depboylu Naci Çine Müjdat Uysal Gülçin Aykaç‐Toker 《Cell biochemistry and function》2009,27(2):76-80
Cholesteryl ester transfer protein (CETP) plays a central role in high‐density lipoprotein (HDL) metabolism. Genetic polymorphisms of the CETP gene can influence levels of serum lipoproteins. It has been reported that mean HDL‐cholesterol (HDL‐C) concentrations are low in Turkish population. Thus, we investigated the frequencies of the common I405V and TaqIB polymorphisms of the CETP gene and their relation to serum lipid and lipoprotein levels in a Turkish population. The variant allele frequencies of I405V and TaqIB polymorphisms of the CETP gene were found to be 0.38 and 0.46, respectively and similar to some of the European populations. Subjects for the VV genotype of I405V polymorphism had higher HDL‐C levels than did II subjects. The covariance analysis showed that gender and triglyceride (TG) levels have an effect on the association of HDL‐C and I405V polymorphism. In conclusion, our results indicate that I405V polymorphism may affect the HDL‐C levels in Turkish population. The association of this polymorphism and HDL‐C levels could be modified by other factors, such as gender and TG levels. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献