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111.
The present study was designed to investigate the effect of CdCl2-polluted drinking water (40 mg CdCl2/L) on the level of TNF-α and IL-6, as well as oxidative status biomarkers in plasma of rats. The possible protective effect of oral administration of curcumin (50 mg/kg body weight/day) was assessed. Results illustrated that Cd exposure significantly elevated the plasma levels of TNF-α and IL-6 (p < 0.001) as compared to normal rats. Also, Cd administration resulted in a significant elevation in the lipid peroxidation and markedly reduction in the activities of SOD and catalase as well as the level of glutathione and total antioxidant capacity in plasma. The co-treatment of Cd with curcumin significantly reduced the levels of TNF-α and IL-6 and ameliorated the alteration in oxidative status biomarkers induced by Cd. Negative correlation between IL-6 or TNF-α was and the plasma activities of catalase, SOD and the level of total antioxidant capacity were found in rats exposed to Cd. Conclusion: Cadmium toxicity induced the release of TNF-α and IL-6 which is associated with systemic oxidative stress. This may be involved in the mechanism of the Cd toxicity. On the other hand, the findings suggest the curative action of curcumin against Cd toxicity.  相似文献   
112.

Objective

The purpose of this study was to investigate the neuroprotective effects of intraperitoneal injection of hydrogen (H2) in rabbits with cardiac arrest (CA).

Methods

A rabbit model of CA was established by the delivery of alternating current between the esophagus and chest wall to induce ventricular fibrillation. Before CA, the animals were randomly divided into four groups: a sham group (no CA), a CA group, a CA + low dose (10 ml/kg) H2 group (CA + H2 group 1), and a CA + high dose (20 ml/kg) H2 group (CA + H2 group 2). In the first experiment, animals were observed for 72 h after the restoration of spontaneous circulation (ROSC). The neurological scores were assessed at 24, 48 and 72 h after ROSC. The rabbits that survived until 72 h were sacrificed using an overdose of anesthetic, and the brain tissues were collected and Nissl-stained to observe nerve cell damage in the hippocampal CA1 area. In addition, TUNEL assay was performed to detect apoptosis. In the second experiment, animals were observed for 6 h after ROSC. Blood samples and brain hippocampal tissues were collected, and differences in oxidative stress indicators were compared among the four groups.

Results

Intraperitoneal injection of H2 improved the 72-h survival rate and neurological scores, reduced neuronal injury and inhibited neuronal apoptosis. Intraperitoneal injection of H2 reduced oxidative stress indicators in the plasma and hippocampal tissues and enhanced antioxidant enzyme activity. No significant difference was observed between the two CA groups treated with different doses of H2.

Conclusions

Intraperitoneal injection of H2 is a novel hydrogen administration method and can reduce cerebral ischemia-reperfusion injury and improve the prognosis of cardiopulmonary cerebral resuscitation in a rabbit model of CA.  相似文献   
113.
We have shown that platinum nanoparticles (nano-Pt) are a superoxide dismutase (SOD)/catalase mimetic. Various data have shown extension of the Caenorhabditis elegans lifespan by antioxidant treatment. The present study was designed to elucidate the survival benefit conferred by nano-Pt, as compared to the well-known SOD/catalase mimetic EUK-8. At 0.5mM, nano-Pt significantly extended the lifespan of wild-type N2 nematodes and at 0.25 and 0.5mM, nano-Pt recovered the shortened lifespan of the mev-1(kn1) mutant, which is due to excessive oxidative stress. In both instances, EUK-8 at 0.05, 0.5, and 5mM did not extend nematode lifespan. Even when 0.4M paraquat was loaded exogenously, nano-Pt (0.1 and 0.5mM) and EUK-8 (0.5 and 5mM) were effective in rescuing worms. Moreover, 0.5mM nano-Pt significantly reduced the accumulation of lipofuscin and ROS induced by paraquat. We measured the in vitro dose-dependent quenching of O(2)(-) and H(2)O(2), indicating that nano-Pt is a more potent SOD/catalase mimetic than EUK-8. Nano-Pt prolonged the worm lifespan, regardless of thermotolerance or dietary restriction. Taken together, nano-Pt has interesting anti-ageing properties.  相似文献   
114.
Bipolar disorder (BD) is a common and severe mood disorder associated with higher rates of suicide and disability. Ouabain, a Na(+)/K(+)-ATPase inhibitor, induces behavioral changes in rats and has been used as a model of mania. The aim of this study was to investigate if diphenyl diselenide [(PhSe)(2)], an organoselenium compound with pharmacological properties, is effective against ouabain-induced hyperactivity and alterations in cerebral oxidative status of rats. Male Wistar rats were treated with a single dose of (PhSe)(2) (50 mg/kg, p.o.) 30 min before i.c.v. injection of ouabain (5 μl, 10(-5) M) or with the mood stabilizer, lithium chloride (LiCl) (45 mg/kg, p.o.), twice a day, for 7 days before the administration of ouabain. Open-field locomotion was quantified after ouabain administration. Thiobarbituric acid reactive substances (TBARS), oxidatively modified proteins, tyrosine nitration, ascorbic acid and non-protein thiols (NPSH) levels and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activities were determined in the whole brain. Ouabain increased locomotor activity in the open-field test and pretreatment with (PhSe)(2) or LiCl blocked this effect. In addition, ouabain increased lipid peroxidation and oxidatively modified proteins, demonstrated by a significant increase in TBARS levels and carbonyl content, which were attenuated by pretreatment with (PhSe)(2) or LiCl. The activities of SOD and CAT were increased by ouabain. LiCl was effective on preventing the increases of both enzyme activities, but (PhSe)(2) attenuated the ouabain effect in SOD activity. GPx and GR activities, ascorbic acid, NPSH and tyrosine nitration levels were not altered in all experimental groups. Similarly to LiCl, (PhSe)(2) produced an antimanic-like action, since it was effective against the locomotor hyperactivity elicited by ouabain. The results also indicated that (PhSe)(2) was effective against oxidative stress caused by ouabain in rats.  相似文献   
115.
116.
The actions of resveratrol in brain and plasma of rats with adjuvant‐induced arthritis were investigated. Resveratrol was administered orally during a period of 23 days. A major concern of the present work was to explore an ample range of daily doses (10‐200 mg/kg). Several oxidative and inflammatory markers were measured. Important effects of resveratrol treatment were the normalization of the plasma myeloperoxidase activity (inflammatory marker), the normalization of the brain xanthine oxidase activity (reactive oxygen species source) and the near‐normalization of the catalase activity in the brain (antioxidant defence). These effects presented obvious dose dependencies in the range up to 200 mg/kg. Resveratrol also reduced protein and lipid damage within the lowest dose ranges investigated, and its action as a free radical scavenger activity was enhanced in brain mitochondria of arthritic rats. Resveratrol failed in restoring the diminished albumin levels and plasma protein thiols in arthritic rats. The latter, however, were substantially increased in healthy rats at low doses (up to 50 mg/kg), a sign of antioxidant action. This increase was reversed at higher doses, a sign of pro‐oxidant action. The observations agree with the notion that low doses of resveratrol might be useful as an adjuvant to the conventional antirheumatic drugs.  相似文献   
117.
目的:研究大豆异黄酮对糖尿病大鼠心肌损伤的保护作用。方法:采用腹腔注射链脲佐菌素(streptozotocin,STZ)的方法制备2型糖尿病大鼠模型,取100只模型大鼠随机分为模型组,大豆异黄酮40 mg·kg~(-1)组、80 mg·kg~(-1)组、160mg·kg~(-1)组、320 mg·kg~(-1)组,每组20只;另设正常对照组。给药治疗8周后,测定各组大鼠体质量和心脏指数;检测血清中谷草转氨酶(aspartate transaminase,AST)、乳酸脱氢酶(lactate dehydrogenase,LDH)、肌酸激酶(creatine kinase,CK)、丙二醛(Malondialdehyde,MDA)含量以及总抗氧化能力(total antioxidant capacity,TAOC);测定心肌组织中超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)活性;通过苏木精-伊红(Hematoxylin-Euphorbia,HE)染色观察心肌组织病理学改变,通过TUNEL染色观察心肌细胞凋亡状况并计算凋亡指数(apoptosis index,AI)。结果:与模型组比较,大豆异黄酮80 mg·kg~(-1)组、160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠血清AST、LDH、CK、MDA水平显著降低(P0.05,P0.01),心肌组织中SOD、CAT活性显著升高(P0.05,P0.01);大豆异黄酮160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠体质量显著增高、心脏指数显著降低(P0.05);血清中TAOC显著升高(P0.05);大豆异黄酮各组心肌组织病理学改变和心肌细胞凋亡程度均出现不同程度的改善,并且大豆异黄酮160 mg·kg~(-1)组、320 mg·kg~(-1)组大鼠心肌细胞AI显著降低(P0.05,P0.01)。上述各指标变化均以320 mg·kg~(-1)组最为显著。结论:大豆异黄酮能够有效改善糖尿病大鼠体质量,降低心脏指数,改善心肌组织抗氧化酶系统活性、抑制自由基损伤,抑制心肌组织病变和细胞凋亡,提示大豆异黄酮对糖尿病大鼠心肌组织具有保护作用。  相似文献   
118.
Context: Ionidium suffruticosum (L.) Ging (Violaceae) is an important medicinal plant widely used as a herbal traditional medicine in Ayurveda for the treatment of infertility. Currently, little pharmacological information is available on its male fertility properties following prolonged use.

Objective: To investigate I. suffruticosum leaf extracts for male fertility parameters.

Materials and methods: The ethanol lyophilized fraction was administered orally on carbendazim-induced sub-fertility rats (250?mg/kg body weight for 28 days). The effects of fractions on rat’s fertility parameters i.e., body and testes weight, sperm motility, sperm vitality, epididymal sperm counts, its morphology, enzyme and antioxidant stress and histopathology were studied and compared with clomiphene citrate.

Results: The sub-fertile male rats treated with I. suffruticosum leaf extract increased the body weight of 7?g, testis weight of 97?mg, increased cauda epididymal sperm counts of 34.2?×?106 sperm/mL, motility of sperm 46% and vitality 28% also increased and normal sperm morphology also improved up to 32%. The carbendazim-treated group showed loss in body weight of 33?g, testis weight of 851?mg, decreased epididymal sperm counts of 15?×?106 sperm/mL, with sluggish motility and a highly significant fall in the live sperms of about 57%.

Discussion and conclusion: The leaf fraction of I. suffructicosum increased the testicular weight, spermatogenesis, sperm counts, lessened sperm agglutination, and increased testicular oxidative biomarkers, SOD, and CAT. This study therefore supports the usage of I. suffructicosum in traditional medicine for infertility.  相似文献   
119.
Dichloroacetate (DCA) is used for different medical and industrial purposes and has been found to be a toxic by-product produced during the process of water chlorination. The DCA effects on superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) activities and glutathione (GSH) level were assessed and correlated with each other and also with cellular viabilities in J774A.1 macrophage cells. A concentration of 24 mm of DCA resulted in time-dependent decreases in cellular viability and glutathione level, and time-dependent increases in SOD activity when incubated with the cells for 24-48 h. DCA also resulted in significant increases in CAT and GSH-Px activities of the viable cells when incubated with the cells for 36 and 48 h. The changes in antioxidant enzyme activities and GSH levels were found to be strongly correlated with each other, and with cellular viabilities at different time points. While GSH did not result in any significant effects when added to the cells at concentrations ranging between 15 and 60 nmol ml(-1), it resulted in concentration-dependent increases in cellular viability when added to the DCA-treated cells, with maximal effects achieved at 45-60 nmol GSH ml(-1). However, cellular viability of the GSH + DCA treated cells remained below that of the control. Since viable cells from the DCA-treated cultures displayed significantly higher antioxidant enzyme activities compared with the control, it is concluded that those increases may have contributed to the cellular protection against DCA-induced cell death. Also, glutathione depletion has a major contribution to the observed cellular death induced by DCA.  相似文献   
120.
Many tropical plants have interesting biological activities with potential therapeutic applications. Garcinia mangostana Linn. (GML) belongs to the family of Guttiferae and is named “the queen of fruits”. It is cultivated in the tropical rainforest of some Southeast Asian nations like Indonesia, Malaysia, Sri Lanka, Philippines, and Thailand. People in these countries have used the pericarp (peel, rind, hull or ripe) of GML as a traditional medicine for the treatment of abdominal pain, diarrhea, dysentery, infected wound, suppuration, and chronic ulcer.  相似文献   
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