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991.
We studied photosynthetic acclimation of eastern hemlock [Tsuga canadensis (L.) Carr.] seedlings in the first month after sudden exposure of shade-grown seedlings to full sunlight. In a greenhouse
experiment, seedlings were grown under full sun or 80% shade, and after 7 months, a sample of the shaded trees was transferred
to full sun in the greenhouse. Photosynthetic responses of shaded, transferred, and sun trees were followed over the course
of 26 days to track short to medium-term acclimation responses. A partial acclimation of photosynthesis at high light occurred
in pre-existing (formed in the previous environment) and new foliage of transferred seedlings. This was associated with non-stomatal
limitations to photosynthesis. Pre-existing foliage of transferred plants had a prolonged reduction in the ratio of variable
to maximal fluorescence, and a limited capacity to adjust photochemical quenching or photosystem II quantum yield in the light
to increasing light intensity compared to sun foliage, and apparently had some difficulty sustaining non-photochemical quenching.
Seedling survival was only 58% among transferred seedlings, compared to 80% and 100% in the shade or sun groups, respectively.
Photosystem II quantum yield in the light, and photochemical and non-photochemical quenching were similar between newly formed
foliage of transferred and sun plants. These findings indicate that eastern hemlock depends strongly on the production of
new foliage for photosynthetic adjustments to high light, and that development of photosynthetic competence may be a gradual
process that occurs over successive foliar production cycles.
Received: 12 May 1998 / Accepted: 27 July 1998 相似文献
992.
Mohammed Mebarek Bia Seongjun Choe Barakaeli Abdieli Ndosi Hansol Park Yeseul Kang Chatanun Eamudomkarn Tilak Chandra Nath Sunmin Kim Hyeong-Kyu Jeon Dongmin Lee Keeseon S. Eom 《The Korean journal of parasitology》2021,59(5):457
Cystic echinococcosis is a zoonotic parasitic disease caused by Echinococcus species. Tanzania is one of the endemic countries with cystic echinococcosis. This study focussed on identifying genotypes of Echinococcus spp. in Tanzania. We collected 7 cysts from cattle in Mwanza municipal (n=4) and Loliondo district (n=3). The cysts from Mwanza were all E. ortleppi and fertile. In contrast, the cysts from Loliondo were all E. granulosus sensu stricto and sterile. Two from the 4 cysts were a new haplotype of E. ortleppi (G5). These results can improve the preventive and control programs for humans and livestock in Tanzania. To our knowledge, this study is considered the first to identify the genotype and haplotype of Echinococcus spp. in Tanzania. 相似文献
993.
Azza I. Othman Mohammed A. El Missiry 《Journal of biochemical and molecular toxicology》1998,12(6):345-349
Male albino rats were intramuscularly administered a single dose of lead acetate (100 μmol/kg b.wt). Another group of rats were injected with sodium selenite (10 μmol/kg b.wt) before lead intoxication. After 3 and 24 hours, lead treatment resulted in significant increases in acid and alkaline phosphatases, GOT and GPT, total proteins, and cholesterol in serum. The total triglycerides in serum was decreased after 24 hours of intoxication. Lead treatment also produced significant elevation of lipid peroxidation in liver and kidney. The antioxidant capacity of hepatic and renal cells in terms of the activities of superoxide dismutase, glutathione reductase, and glutathione content was diminished. It appears from these results that lead may exert its toxic effect via peroxidative damage to renal and hepatic cell membranes after 24 hours. Selenium administration prior to lead injection produced pronounced prophylactic action against lead effects, and it is observed that selenium enhances the endogenous antioxidant capacity of the cells by increasing the activities of the superoxide dismutase and glutathione reductase and the glutathione content. As a result, the lipid peroxidation was decreased in both liver and kidney. © 1998 John Wiley & Sons, Inc. J Biochem Mol Toxicol 12: 345–349, 1998 相似文献
994.
Ahmed M. Ahmed Medhat M. Haikal Ahmed A. Mohammed Mohammed A. Zidan 《International Review of Hydrobiology》1986,71(1):127-138
Monthly variations of some physical and chemical characteristics of Nile waters at Assiut (375 km south from Cairo, Egypt) during the period from September 1980 to September 1982 were followed and discussed. As expected, the maximum temperature was recorded in summer and the minimum in winter. The pH values of Nile waters were recorded to be in the vicinity of 8.0. The highest oxygen concentrations were recorded in the summer months, mainly due to the relatively high photosynthetic activity. The total soluble salts and the total alkalinity exhibited almost identical trends. Nitrate, phosphate, silicate and chloride concentrations showed no major regular trends. The cation abundances by weight were as follows: Ca2+ > Na+ > Mg2+ > K+. 相似文献
995.
Khalid Farouq Al-rawi Hameed Hussein Ali Manaf Abdulrahman Guma Bilal Jasir Mohammed Aldahham Shakir Faris Tuleab Alaaraji Osamah Al-ani Aus Tariq Ali 《Reports of Biochemistry & Molecular Biology》2022,10(4):664
Background:Chronic kidney disease (CKD), is a major public health challenge worldwide. It is more prevalent in developed countries compared with the rest of the world, due to the higher rates of life expectancy and unhealthy lifestyle related factors. This aim of the current study is to evaluate the relationship between interleukins IL-2 and IL-17 concentrations and kidney function markers in men with CKD.Methods:Forty-five men with CKD and seventy controls were enrolled in the current study to assess the relationship between interleukin-2 (IL-2), interleukin-17 (IL-17), and CKD parameters. Fasting blood samples were collected from patients with CKD and their controls at same time. Serum IL-2, and IL-17 were measured in patients with CKD and their controls, and then the relationship between these interleukins and serum creatinine, serum urea, serum uric acid and urine albumin were evaluated.Results:A significant relationship was detected between IL-2 (p< 0.001), IL-17 (p< 0.001) levels and serum creatinine concentrations. The significant increase of IL-2 and IL-17 levels were also paralleled with a significant increase in serum urea (p< 0.001), and urine albumin (p< 0.001) concentrations respectively.Conclusion:IL-2 and IL-17 may play a critical role in the pathophysiology of CKD. The significant increase of IL-2 and IL-17 is associated with significantly high concentrations of creatinine, serum urea and urine albumin suggesting that these interleukins may be used as targets for future biomarkers and molecular therapy. However, due to limited sample size of the current study, larger prospective cohorts are needed to confirm these observations.Key Words: Chronic kidney disease, Interleukins, Serum creatinine, Serum urea, Urine albumin 相似文献
996.
Hanan Sharaf El-Deen Mohammed Manal Mohamed Kamal Hala Mostafa ElBadre Amal Hosni Azza Abo Elfadl Mohamed Ahmed Mostafa Reham Ibrahim El-Mahdy 《Reports of Biochemistry & Molecular Biology》2022,10(4):537
Background:Oxidized low-density lipoprotein (ox-LDL) has an important role in the genesis of coronary atherosclerosis. Lectin-like ox-LDL receptor 1 (OLR1) contributes to the uptake and internalization of ox-LDL. Genetic polymorphisms have been associated with coronary artery disease (CAD). Here we explore the association of plasma levels of ox-LDL and 3′ UTR OLR1 (rs1050286) SNP with CAD risk and in-hospital adverse outcomes.Methods:A case-control study enrolled 192 patients with ST-segment elevation myocardial infarction (STEMI), 100 patients with unstable angina, and 100 healthy controls. Baseline, clinical characteristics, and risk scores of the patients were determined. Plasma ox-LDL and other biochemical variables were measured. All subjects are genotyped for OLR1 (rs1050286) by RT-PCR with TaqMan SNP genotyping assay.Results:Plasma ox-LDL was higher with enhanced sensitivity and specificity in identifying patients with STEMI and was found as a significant independent risk factor for CAD in those two groups. Levels of ox-LDL were increased with increasing poor prognostic factors in STEMI patients that are associated with an increased incidence of some adverse events and in-hospital mortality. Elevated STEMI risk was associated with T allele of OLR1 (rs1050286) (odds ratio of 4.9, 95% CI: 2.6-9.4, p< 0.001). STEMI patients who have T allele exhibited higher risk scores, coronary multivessel narrowing, and elevated incidence of in-hospital major adverse clinical events.Conclusion:These results suggest that plasma ox-LDL, as well as T allele of ORL-1 (rs1050286), is associated with the increased risk for developing STEMI and the associated adverse clinical outcomes.Key Words: Coronary artery disease, genotyping, OLR1, outcomes, Oxidized low-density lipoprotein 相似文献
997.
998.
Hadeel Ahmed Kenoosh Harikumar Pallathadka Ahmed Hjazi Aiman Mohammed Baqir Al-Dhalimy Sajad Ali Zearah Pallavi Ghildiyal Zuhair I. Al-Mashhadani Yasser Fakri Mustafa Manar Mohammed Hizam Ahmed Elawady 《Cell biochemistry and function》2024,42(2):e3954
The messenger RNA (mRNA) vaccines have progressed from a theoretical concept to a clinical reality over the last few decades. Compared to conventional vaccination methods, these vaccines have a number of benefits, such as substantial potency, rapid growth, inexpensive production, and safe administration. Nevertheless, their usefulness was restricted up to now due to worries about the erratic and ineffective circulation of mRNA in vivo. Thankfully, these worries have largely been allayed by recent technological developments, which have led to the creation of multiple mRNA vaccination platforms for cancer and viral infections. The mRNA vaccines have been demonstrated as a powerful alternative to traditional conventional vaccines because of their high potency, safety and efficacy, capacity for rapid clinical development, and potential for rapid, low-cost manufacturing. The paper will examine the present status of mRNA vaccine technology and suggest future paths for the advancement and application of this exciting vaccine platform as a common therapeutic choice. 相似文献
999.
1000.
Ibrahim A. Darwish Nourah Z. Alzoman Nehal N. Khalil Mohammed S. Alsalhi 《Luminescence》2024,39(5):e4747
Atezolizumab (ATZ) is a human monoclonal antibody, which has been granted multiple approvals from the US Food and Drug Administration (FDA) for the immunotherapy of different types of cancer. This study describes the prototype of a time-resolved fluoroimmunoassay (TRFIA) for the quantitation of ATZ in plasma. The assay involved the non-competitive binding of ATZ to its specific antigen [programmed death-ligand 1 (PD-L1) protein]. The immune complex formed on the inner surface of the assay plate wells was quantified by anti-human secondary antibody labeled with a chelate of europium-ethylenediaminetetraacetic acid. The enhanced fluorescence signal was generated by an enhanced fluorescence solution composed of thenoyltrifluoroacetone, trioctylphosphine oxide, and Triton X-100. The conditions of the TRFIA were refined, and its optimum procedures were established. The assay was validated in accordance with the immunoassay validation guidelines, and all the validation parameters were acceptable. The working range of the assay was 20–1000 pg mL−1, and its limit of quantitation was 20 pg mL−1. The assay was applied to the quantitation of ATZ in plasma samples with satisfactory accuracy and precision. The proposed TRFIA has significant benefits over the existing methodologies for the quantitation of ATZ in clinical settings. 相似文献