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排序方式: 共有252条查询结果,搜索用时 31 毫秒
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Sevgi Yardim-Akaydin Aylin Sepici Yeşim Özkan Meral Torun Bolkan Şimşek Vesile Sepici 《Free radical research》2013,47(6):623-628
Free radicals are implicated in many diseases including atherosclerosis, cancer and also in rheumatoid arthritis. Reaction of uric acid with free radicals, such as hydroxyl radical and hypochlorous acid (HOCl) results in allantoin production. In this study, we measured the serum allantoin levels, oxidation products of uric acid, as a marker of free radical generation in rheumatoid arthritis. Fasting blood samples were obtained from 21 rheumatoid patients and 15 healthy controls. In this study, the serum allantoin and uric acid levels were measured by a gas chromatography–mass spectrometry method and the ratios were calculated. The mean allantoin and uric acid levels and ratios in the patient group were 22.1±11.3, 280.5±65.0 and 8.0±3.7?μM, while in the control group they were 13.6±6.3, 278.3±53.6 and 4.9±2.1?μM, respectively. The effects of gender, age, menopausal status, duration of disease and medications on serum allantoin and uric acid levels of the patient and control groups were studied. Our results suggest that uric acid acts as a free radical scavenger and thus is converted to allantoin. Increased allantoin levels suggest the possible involvement of free radicals in rheumatoid arthritis. 相似文献
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Figen Seymen Youn Jung Kim Ye Ji Lee Jenny Kang Tak-Heun Kim Hwajung Choi Mine Koruyucu Yelda Kasimoglu Elif Bahar Tuna Koray Gencay Teo Jeon Shin Hong-Keun Hyun Young-Jae Kim Sang-Hoon Lee Zang Hee Lee Hong Zhang Jan C-C. Hu James P. Simmer Eui-Sic Cho Jung-Wook Kim 《American journal of human genetics》2016,99(5):1199-1205
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Effects of a GnRH agonist on oocyte number and maturation in mice superovulated with eCG and hCG 总被引:4,自引:0,他引:4
The objective was to investigate the effects of a gonadotropin-releasing hormone agonist (GnRH) on ovulation rate and the number and maturation of oocytes in mice superovulated with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG). Thirty 3-month-old BALB/C female mice (weight: 25-30 g) were assigned to three experimental groups: control, superovulated, and superovulated with GnRH pretreatment (n=10 per group). Control mice received an i.p. injection of 0.1 ml physiological saline solution. Superovulation was induced with 5 IU eCG (i.p.) and 5 IU hCG 48 h later. Mice in the superovulated with GnRH pretreatment group were given GnRH (20 mg/kg Fertirelin, i.m.), 24 h before superovulation. Thirteen hours after hCG administration, mice were sacrificed by cervical dislocation and blood samples were collected to determine serum progesterone concentration (by radioimmunoassay). Ovaries and oviducts were also harvested to enumerate corpora lutea and cumulus-enclosed oocytes. Progesterone concentrations were not significantly different among groups. The oocyte number and the maturation, ovulation rate, and the number of corpora lutea were higher in GnRH-treated mice than both controls and superovulated mice. In conclusion, GnRH given 24 h before superovulation with eCG-hCG increased the number and maturation of oocytes and the rate of ovulation in mice. 相似文献
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Protective effects of ascorbic acid, Dl-α-tocopherol acetate, and sodium selenate on ethanol-induced gastric mucosal injury of rats 总被引:2,自引:0,他引:2
Ozdil S Yanardag R Koyuturk M Bolkent S Arbak S 《Biological trace element research》2004,99(1-3):173-189
In this study, the effect of ascorbic acid (vitamin C), Dl-α-tocopherol acetate (vitamin E), and sodium selenate (selenium) on ethanol-induced gastric mucosal injury in rats was investigated
morphologically and biochemically. The gastric mucosal injury was produced by administration of 1 mL of absolute ethanol to
each rat. Animals received vitamin C (250 mg/kg), vitamin E (250 mg/kg), and selenium (0.5 mg/kg) for 3 d 1 h prior to the
administration of absolute ethanol. In gastric mucosa of rats given ethanol according to control groups, neuronal nitric oxide
expression decreased. This immunoreactivity was much lower in the group given ethanol+vitamin C+vitamin E+selenium than the
control group and the ethanol-induced group. Scanning electron microscopic evaluation of the ethanol-induced group, when compared
to control groups, revealed degenerative changes in gastric mucosa, whereas a good arrangement in surface topography of gastric
mucosa in the group given ethanol + vitamin C+vitamin E + selenium was observed. In the group administered ethanol, a reduction
of the stomach glutathione (GSH) and serum total protein levels and increases in serum sialic acid, triglycerides, and stomach
lipid peroxidation (LPO) levels were observed. Vitamin C+vitamin E+Se administration to alcohol-treated rats significantly
increased the serum total protein, triglyceride levels, and stomach GSH levels and significantly lowered the levels of serum
sialic acid and stomach LPO compared to untreated alcohol-supplemented rats. As a result of these findings, we can say that
the combination of vitamin C, vitamin E, and selenium has a protective effect on ethanol-induced gastric mucosal injury of
rats. 相似文献
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Identification of a novel HLA-B60-restricted T cell epitope of the minor histocompatibility antigen HA-1 locus 总被引:7,自引:0,他引:7
Mommaas B Kamp J Drijfhout JW Beekman N Ossendorp F Van Veelen P Den Haan J Goulmy E Mutis T 《Journal of immunology (Baltimore, Md. : 1950)》2002,169(6):3131-3136
The polymorphic minor histocompatibility Ag HA-1 locus encodes two peptides, HA-1(H) and HA-1(R), with a single amino acid difference. Whereas the immunogenicity of the HA-1(R) allele has not yet been shown, the nonameric HA-1(H) peptide induces HLA-A2-restricted cytotoxic T cells in vivo and in vitro. It is not known whether the mHag HA-1(H) or HA-1(R) associates with other HLA class I molecules. Therefore, the polymorphic regions of both HA-1 alleles were analyzed to identify HLA class I binding peptides that are properly processed by proteasomal degradation. Peptide binding analyses were performed for all nonameric HA-1(H/R) peptides for binding to nine HLA class I molecules with >10% prevalence in the Caucasian population and for seven nonameric/decameric HA-1(H/R) peptides predicted to bind to HLA-A3, -B14, and -B60. Only the nonameric KECVL(H)/(R)DDL and decameric KECVL(H)/(R)DDLL peptides showed strong and stable binding to HLA-B60. In vitro digestion of 29-aa-long HA-1 peptides by purified 20S proteasomes revealed proper cleavage at the COOH termini of both HLA-B60 binding HA-1(H) and HA-1(R) peptides. In subsequent analyses, dendritic cells pulsed with the nonameric HA-1(R) peptide did not induce CTLs that recognize the natural HLA-B60/HA-1(R) ligand. In contrast, dendritic cells pulsed with the nonameric HA-1(H) peptide induced IFN-gamma-secreting T cells specific for the natural HLA-B60/HA-1(H) ligand in three HLA-B60(+) HA-1(RR) individuals, demonstrating the immunogenicity of the HLA-B60/HA-1(H) ligand. In conclusion, this study shows a novel HLA-B60-restricted T cell epitope of the minor histocompatibility Ag HA-1 locus. 相似文献
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This study was designed to investigate the effects of Nigella sativa L. (NS), known as black seed, or/and Urtica dioica L. (UD), known as stinging nettle root, treatments on serum Na, K, Cl, and Ca levels and some hematological values of CCl4-treated rats. Sixty healthy male Sprague-Dawley rats, weighing 250–300 g, were randomly allotted into 1 of 4 experimental
groups: A (CCl4-only treated), B (CCl4+UD treated), C (CCl4+NS treated), and D (CCl4+UD+NS treated), each containing 15 animals. All groups received CCl4 (0.8 mL/kg of body weight, subcutaneously, twice a week for 90 d starting d 1). In addition, B, C, and D groups also received
the daily ip injection of 0.2 mL/kg NS and/or 2 mL/kg UD oils for 45 d starting d 46. Group A, on the other hand, received
only 2 mL/kg normal saline solution for 45 d starting d 46. Blood samples for the biochemical analysis were taken by cardiac
puncture from five randomly chosen rats in each treatment group at the beginning, d 45, and d 90 of the experiment. The CCl4 treatment for 45 d significantly (p<0.05) increased the serum K and Ca and decreased (p<0.05) the red blood cell count (RBC), white blood cell count (WBC), packed cell volume (PCV), and Hb levels without changing (p>0.05) the serum Na and Cl levels. NS or UD treatments (alone or combination) for 45 d starting d 46 significantly (p<0.05) decreased the elevated serum K and Ca levels and also increased (p<0.05) the reduced RBC, WBC, PCV, and Hb levels. It is concluded that NS and/or UD treatments might ameliorate the CCl4-induced disturbances of anemia, some minerals, and body’s defense mechanism in CCl4-treated rats. 相似文献
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Gülay Bayramoğlu Meral Karakışla Begum Altıntaş Ayşegül U. Metin Mehmet Saçak M. Yakup Arıca 《Process Biochemistry》2009,44(8):880-885
Polyacylonitrile fibers (PAN) surfaces were modified with chemical polymerization of conductive polyaniline (PANI) in the presence of potassium dichromate as an oxidizing agent. The effect of aniline concentration on the grafting efficiency and on the electrical surface resistance of PAN/PANI composite fibers was investigated. The surface resistance of the conductive composite fibers in this work was found to be between 8.0 and 0.5 kΩ/cm. As the amount of grafted PANI increased on the PAN fibers the electrical resistance of composite fibers decreased. The PAN/PANI composite fibers were characterized by SEM and FTIR studies. Composite PAN/PANI fibers were used for reversible immobilization of invertase. The immobilization efficiency and the activity of the immobilized invertase (from 1.0 mg/mL invertase solution at pH 5.5) were increased with increasing PANI contents of the composite fibers. The maximum amount of immobilized enzyme onto composite fibers containing 2.0% PANI was about 76.6 mg/g. The optimum pH for the free enzyme was observed at 5.0. On the other hand, immobilized invertase yielded a broad optimum pH profile between pH 5.0 and 7.0. Immobilized invertase exhibited 83% of its original activity even after two months storage at 4 °C while the free enzyme showed only 7% of its initial activity. 相似文献