全文获取类型
收费全文 | 370篇 |
免费 | 12篇 |
出版年
2023年 | 4篇 |
2022年 | 1篇 |
2021年 | 11篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 9篇 |
2017年 | 15篇 |
2016年 | 16篇 |
2015年 | 14篇 |
2014年 | 20篇 |
2013年 | 33篇 |
2012年 | 25篇 |
2011年 | 20篇 |
2010年 | 22篇 |
2009年 | 10篇 |
2008年 | 25篇 |
2007年 | 31篇 |
2006年 | 28篇 |
2005年 | 19篇 |
2004年 | 10篇 |
2003年 | 16篇 |
2002年 | 15篇 |
2001年 | 5篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1995年 | 1篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1979年 | 1篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1971年 | 2篇 |
排序方式: 共有382条查询结果,搜索用时 171 毫秒
91.
Cinaz P Karakasü DS Camurdan MO Bideci A Ayvali ED Yücel C 《Biological trace element research》2004,100(3):185-193
This study was planned to investigate goiter prevalence and serum selenium and urine iodine status among school-age children
in the Ankara region of Turkey. Nine hundred five (905) children were investigated; 847 of them were included in the study.
Thyroid ultrasound was performed on children who were suspected of being goitrous at physical examination. Serum TSH, thyroxine,
triiodotyronine, thyroid antibody, and urine iodine concentrations (UIC) are also measured. Ultrasound measurements revealed
a goiter in 107 (12.6%) of the 847 children. Goiter prevalence was significantly lower among iodized-salt users compared to
the noniodized salt using group. UIC and serum selenium levels in the goitrous group were significantly lower compared to
the nongoitrous group. Despite legally enforced table salt iodization, the region shows the characteristics of mild iodine
deficiency. In addition to lower UIC, goitrous children have lower serum selenium levels compared to the nongoitrous ones.
Thus, selenium deficiency plays an important role in goiter endemics in Turkey. It can be postulated that table salt iodization
might not be enough for the preventive measures of goiter, but informing people about the correct ways of iodized salt consumption,
enforcing the iodization of industrial salts, and, as important as these measures, taking selenium deficiency into consideration
are essential for preventing goiters in endemic areas. 相似文献
92.
Mehmet Cankurtaran Huseyin Celik Ozcan Cakmak Levent Naci Ozluoglu 《Journal of applied physiology》2003,94(6):2166-2172
The influence of nasal valve on acoustic rhinometry (AR) measurements was evaluated by using simple nasal cavity models. Each model consisted of a cylindrical pipe with an insert simulating the nasal valve. The AR-determined cross-sectional areas beyond the insert were consistently underestimated, and the corresponding area-distance curves showed pronounced oscillations. The area underestimation was more pronounced in models with inserts of small passage area. The experimental results are discussed in terms of theoretically calculated "sound-power reflection coefficients" for the pipe models. The reason for area underestimation is reflection of most of the incident sound power from the barrier at the front junction between the pipe and the insert. It was also demonstrated that the oscillations are due to low-frequency acoustic resonances in the portion of the pipe beyond the insert. The results suggest that AR does not provide reliable information about the cross-sectional areas of the nasal cavity posterior to a significant constriction, such as pathologies narrowing the nasal valve area. When the passage area of the nasal valve is decreased, the role of AR as a diagnostic tool for the entire nasal cavity becomes limited. 相似文献
93.
Ozcan Cakmak Huseyin Celik Mehmet Cankurtaran Fuat Buyuklu Nuri Ozgirgin Levent Naci Ozluoglu 《Journal of applied physiology》2003,94(4):1527-1535
We used pipe models to investigate the effects of paranasal sinus ostium size and paranasal sinus volume on the area-distance curves derived by acoustic rhinometry (AR). Each model had a Helmholtz resonator or a short neck as a side branch that simulated the paranasal sinus and sinus ostium. The AR-derived cross-sectional areas posterior to the ostium were significantly overestimated. Sinus volume affected the AR measurements only when the sinus was connected via a relatively large ostium. The experimental area-distance curve posterior to the side branch showed pronounced oscillations in association with low-frequency acoustic resonances in this distal part of the pipe. The experimental results are discussed in terms of theoretically calculated "sound-power reflection coefficients" for the pipe models used. The results indicate that the effects of paranasal sinuses and low-frequency acoustic resonances in the posterior part of the nasal cavity are not accounted for in the current AR algorithms. AR does not provide reliable information about sinus ostium size, sinus volume, or cross-sectional area in the distal parts of nasal cavity. 相似文献
94.
The aim of our study was to investigate the protective effects of intraperitoneally-administrated vitamin E, dlalpha lipoic acid, and linalool on the level of total lipid and fatty acid in guinea pig brains with oxidative stress that was induced by H2O2. The total brain lipid content in the H2O2 group decreased when compared to the H2O2 + vitamin E (p<0.05), H2O2+ linalool (p<0.05), ALA (p<0.05), control (p<0.01), linalool (p<0.01), and vitamin E (p<0.01) groups. While the proportion of total saturated fatty acid ( infinity SFA) in the H2O2 group significantly increased (p<0.005) when compared to the vitamin E group, it only slightly increased (p<0.01) when compared to the control and H2O2 + vitamin E groups. The ratio of the total unsaturated fatty acid (infinity USFA) in the H2O2 groups was lower (p<0.05) than the control, vitamin E, and H2O2+ vitamin E groups. The level of the total polyunsaturated fatty acid (infinity USFA) in the H2O2 group decreased in when compared to the control, vitamin E, and H2O2+vitamin E groups. While the proportion of the total w3 (omega 3), w6 (omega 6), and PUFA were found to be lowest in the H2O2 group, they were slightly increased (p<0.05) in the lipoic acid group when compared to the control and H2O2 + lipoic acid groups. However, the level of infinity SFA in the H2O2 group was highest; the level of infinity USFA in same group was lowest. As the proportion of infinity USFA and infinity PUFA were found to be highest in the linalool group, they were decreased in the H2O2 group when compared to the control group. Our results show that linalool has antioxidant properties, much the same as vitamin E and lipoic acid, to prevent lipid peroxidation. Additionally, vitamin E, lipoic acid, and linalool could lead to therapeutic approaches for limiting damage from oxidation reaction in unsaturated fatty acids, as well as for complementing existing therapy for the treatment of complications of oxidative damage. 相似文献
95.
96.
Ozer C Gönül B Elmas C Erdoüan D Ercan ZS 《Molecular and cellular biochemistry》2005,280(1-2):151-157
Dexfenfluramine is one of the anorectic drugs that suppresses food intake which acts via inhibition of reuptake of serotonin
into brain terminal. Gastrointestinal tract is the main source of peripheral serotonin which is involved in the regulation
of gastrointestinal motility. During the use of anorectic drugs, the antioxidant defence is affected especially by reactive
oxygen species.
The purpose of this study to search: The effect of dexfenfluramine on serotonin levels of ileum and the effect of dexfenfluramine
on ileal contractility and oxidative stress.
Materials and Methods: Twenty-two adult male Swiss-albino mice were divided two groups (1) Control, (2) Dexfenfluramine treated
(i.p. twice a day 0.2 mg kg−1 in 0.2 ml saline solution for 7 days). Animal body weights were recorded at the beginning and at the end of the experimental
period. Ileum tissues contractile responses to different concentrations of KCl and acethycholine were recorded on polygraph.
In the meantime ileal tissue malondialdehyde, a product of lipid peroxidation, and glutathione, endogenous antioxidant levels
were assessed by spectrophotometric methods. Ileal tissue serotonin level determined by immunohistochemical method. Body weights
decrease and ileal contractile response of acethycholine increased significantly by dexfenfluramine treatment. Meanwhile,
ileum glutathione levels decreased and malondialdehyde levels increased in dexfenfluramine treated group. Immunohistochemical
detection showed that ileal serotonin levels increased by dexfenfluramine treatments.
As a conclusion, there is a relationship between increased ileal contractility and oxidant status in dexfenfluramine treated
animals. These effects can be related by increased serotonin levels which is induced by dexfenfluramine in ileum. (Mol Cell
Biochem xxx: 151–157, 2005) 相似文献
97.
Development and brain delivery of chitosan-PEG nanoparticles functionalized with the monoclonal antibody OX26 总被引:4,自引:0,他引:4
Aktaş Y Yemisci M Andrieux K Gürsoy RN Alonso MJ Fernandez-Megia E Novoa-Carballal R Quiñoá E Riguera R Sargon MF Celik HH Demir AS Hincal AA Dalkara T Capan Y Couvreur P 《Bioconjugate chemistry》2005,16(6):1503-1511
The inhibition of the caspase-3 enzyme is reported to increase neuronal cell survival following cerebral ischemia. The peptide Z-DEVD-FMK is a specific caspase inhibitor, which significantly reduces vulnerability to the neuronal cell death. However, this molecule is unable to cross the blood-brain barrier (BBB) and to diffuse into the brain tissue. Thus, the development of an effective delivery system is needed to provide sufficient drug concentration into the brain to prevent cell death. Using the avidin (SA)-biotin (BIO) technology, we describe here the design of chitosan (CS) nanospheres conjugated with poly(ethylene glycol) (PEG) bearing the OX26 monoclonal antibody whose affinity for the transferrin receptor (TfR) may trigger receptor-mediated transport across the BBB. These functionalized CS-PEG-BIO-SA/OX26 nanoparticles (NPs) were characterized for their particle size, zeta potential, drug loading capacity, and release properties. Fluorescently labeled CS-PEG-BIO-SA/OX26 nanoparticles were administered systemically to mice in order to evaluate their efficacy for brain translocation. The results showed that an important amount of nanoparticles were located in the brain, outside of the intravascular compartment. These findings, which were also confirmed by electron microscopic examination of the brain tissue indicate that this novel targeted nanoparticulate drug delivery system was able to translocate into the brain tissue after iv administration. Consequently, these novel nanoparticles are promising carriers for the transport of the anticaspase peptide Z-DEVD-FMK into the brain. 相似文献
98.
99.
100.