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31.
目的 研究大鼠视神经挫伤后视神经生长相关蛋白( GAP-43)的变化及重组人促红细胞生成素(rhEPO)的作用.方法 建立外伤性视神经损伤的动物模型,随机分为正常对照组、损伤组(视神经钳夹+生理盐水)及rhEPO组(视神经钳夹+rhEPO),于损伤后1d、4d、7d、14 d和28 d对各组视网膜及视神经进行形态学观察,免疫组化染色法测定视神经GAP-43的活性.结果 rhEPO组较损伤组视网膜及视神经病变明显减轻;在损伤后4d和7d趼组间损伤远端GAP-43表达差异无统计学意义(P>0.05);14 d和28 d rhEPO组损伤远端GAP-43表达较损伤组明显升高(P<0.05).结论 rhEPO对视神经不完全损伤可促进视网膜神经节细胞存活与视神经纤维再生修复.  相似文献   
32.
目的 观察红细胞生成素(EPO)对慢性肾衰竭(CRF)大鼠肾组织归巢因子表达的影响.方法 采用分阶段5/6肾切除制备大鼠CRF模型.实验动物随机分为3组:假手术组、CRF模型组和EPO治疗组.从第3周开始,治疗组大鼠每次皮下注射重组人EPO 50 IU/kg,每周3次,共6周.8周后检测各组大鼠血肌酐(Scr)、血尿素氮(BUN)、尿蛋白、血红蛋白(Hb);采用实时荧光定量PCR、Western印迹和免疫组化方法检测残肾组织EPO及其受体(EPOR)、归巢因子及其受体(SDF-1、CXCR4、Ang-1、Tie2、SCF、c-Kit)的表达.结果 与模型组比较,EPO治疗可上调残肾组织归巢因子及其受体(SDF-1、CXCR4、Ang-1、Tie2、SCF、c-Kit)mRNA和蛋白的表达(均P<0.05);同时,EPO治疗还可上调残肾组织EPO及EPOR的mRNA和蛋白的表达(均P< 0.05).此外,EPO治疗还能下调大鼠Scr、BUN和尿蛋白水平(均P<0.05),上调Hb水平(P<0.05).结论 EPO能改善慢性肾衰竭大鼠的肾功能,这种作用可能与其激活残肾组织归巢因子而参与损伤肾脏的修复有关.  相似文献   
33.
A previous animal study has shown the effects of erythropoietin (EPO) and its non-erythropoietic carbamylated derivative (CEPO) on neurogenesis in the dentate gyrus. In the present study, we sought to investigate the effect of EPO on adult hippocampal neurogenesis, and to compare the ability of EPO and CEPO promoting dendrite elongation in cultured hippocampal neural progenitor cells. Two-month-old male BALB/c mice were given daily injections of EPO (5 U/g) for seven days and were sacrificed 12 hours after the final injection. Proliferation assays demonstrated that EPO treatment increased the density of bromodeoxyuridine (BrdU)-labeled cells in the subgranular zone (SGZ) compared to that in vehicle-treated controls. Functional differentiation studies using dissociated hippocampal cultures revealed that EPO treatment also increased the number of double-labeled BrdU/microtubule-associated protein 2 (MAP2) neurons compared to those in vehicle-treated controls. Both EPO and CEPO treatment significantly increased the length of neurites and spine density in MAP2(+) cells. In summary, these results provide evidences that EPO and CEPO promote adult hippocampal neurogenesis and neuronal differentiation. These suggest that EPO and CEPO could be a good candidate for treating neuropsychiatric disorders such as depression and anxiety associated with neuronal atrophy and reduced hippocampal neurogenesis.  相似文献   
34.
SUMMARY

The National Health Service (NHS) Cancer Plan published in 2000 has a short-term focus on the most pressing problems of improving survival rates and replacing equipment. It also mentioned as a target 'improved quality of life for those affected by cancer'. Continuity of care for longer-term care programmes was seen predominantly in terms of palliative care. Recent National Institute for Clinical Excellence (NICE) reports may have reinforced this approach by focussing on the clinical and cost effectiveness of chemotherapy for late-stage cancer. The impact on local decision-makers has been that drug funds have been prioritised for use on survival-enhancing interventions, with few resources left for short and longer-term supportive care targeted primarily on improving quality of life. Within supportive care, resources are particularly limited for funding treatments such as erythropoietin for the management of cancer-related anaemia, a common and very debilitating side-effect of intensive therapy. The need for a re-focusing on supportive care is associated with cancer becoming, in many instances, a longer-term illness. The prevalence of

cancer is rising markedly due to increased survival rates. However, this creates a new challenge of reducing disability and improving quality of life. In surveys, patients have rated fatigue associated with anaemia as one of the most debilitating effects of their cancer and its treatment with chemotherapy. This paper reviews the evidence demonstrating the quality of life benefits of erythropoietin, and then considers the policy constraints that have limited the adoption of this treatment within the NHS. Through co-ordinated planning there are opportunities for cancer networks and primary care trusts (PCTs) working with cancer centres to develop more support in ways which are feasible and fundable. The case is argued that PCTs and cancer networks, in implementing the Cancer Plan locally, need to integrate short- and longer-term supportive care into their cancer service development plans, and recognise the importance of anaemia management as an integral part of this. Lessons can be learnt from UK renal services where anaemia management with erythropoietin is standard practice.  相似文献   
35.
Purpose: Following methanol intoxication, optic nerve neuropathy may occur, which is currently treated by different therapeutic regimens. Erythropoietin (EPO) has recently been introduced as a good therapeutic option in methanol-induced optic neuropathy. The aim of the current study was to evaluate the efficacy of EPO in improvement of the visual disturbances in methanol-intoxicated patients.

Materials and methods: In a case-control study, all patients who had referred to our toxicology centre with confirmed diagnosis of methanol toxicity were considered to be included. Of them, those who had referred with visual disturbances, survived, and their visual disturbances had not improved after haemodialysis were entered. Cases received EPO and corticosteroids while controls only received corticosteroids. They were then compared regarding their visual outcome.

Results: All five patients in the control group mentioned that after discharge, their visual acuity had improved while in the cases, three mentioned visual improvement, two mentioned their visual acuity had deteriorated after discharge, two mentioned no change in their visual acuity and three mentioned that their visual acuity had first improved but then deteriorated with a mean two-month interval period. In fundoscopic evaluations, two controls had normal fundospcopy while eight cases had abnormal fundoscopy (p?=?0.055).

Conclusions: Protective effect of EPO on methanol-induced optic nerve may be strong at the beginning of the intervention but is probably transient.  相似文献   
36.
《Hemoglobin》2013,37(2):91-106
This review brings some new insights on erythrocytosis of genetic origin related to problems of oxygen delivery by hemoglobin (Hb). A few molecular mechanisms are individualized among the about 100 Hb variants that cause compensatory erythrocytosis. The most frequently observed structural modifications are localized in the α1β2 interface, or at the C-terminal. They impair formation of a stable T state. Others mutations modify directly or indirectly the surrounding of the heme and the site where oxygen binds. A special interest is brought to the dose effect considering the possibility for formation of hybrid tetramers with altered oxygen binding properties. Homozygous cases, and patients who are compound heterozygotes for a high oxygen affinity Hb and a thalassemia (thal), are discussed. Several examples are provided, specially documented for Hb Olympia [β20(B2)Val→Met] and Hb Saint Nazaire [β103(G5)Phe→Ile]. Other mechanisms leading to erythrocytosis are discussed, and finally, an algorithm is proposed for etiological diagnosis.  相似文献   
37.
Background Within hypoxic tumor regions anaerobic dissimilation of glucose is the sole source of energy generation. It yields only 5% of the ATP that is normally gained by means of oxidative glucose catabolism. The increased need for glucose may aggravate cancer cachexia. We investigated the impact of recombinant human erythropoietin (RhEPO) and increased inspiratory oxygen concentrations on weight loss in tumor-bearing mice.Methods Fragments of the murine C26-B adenocarcinoma were implanted in 60 BALB/c-mice. The mice were divided into four groups and assigned to: (A) no treatment; (B) RhEPO- administration (25 IU daily from day 1–11, three times per week from day 12); (C) RhEPO and 25% oxygen; and (D) RhEPO and 35% oxygen. Three control groups of four healthy mice each received the same treatment as groups A, B, and D, respectively. Hematocrit and hemoglobin levels, tumor volume, and body weight were monitored. At day 17 the experiment was terminated and the serum lactate concentration was measured. The tumors were excised and weighed and, for each mouse, the percentage weight loss was calculated. The impact of tumor weight and the treatments on lactate concentration and weight loss was evaluated.Results Significant positive correlations were found between tumor weight and lactate concentration and between tumor weight and percentage weight loss. In the mice with the largest tumors, RhEPO displayed a significant weight loss-reducing effect, and a significant negative correlation was found between hemoglobin concentration and weight loss. An oxygen-rich environment did not appear to influence weight loss.Conclusion Anaerobic glycolysis in a growing C26-B tumor is related to weight loss. RhEPO administration results in a reduction of the percentage weight loss; this effect is probably mediated by an increased hemoglobin concentration.This study was financially supported by a grant from Ortho Biotech, a division of Janssen Cilag, Tilburg, the Netherlands  相似文献   
38.
Forty-six patients with rheumatoid arthritis (RA) and documented anemia of chronic disease (Hb <100/110 g/l) were randomized to receive either human recombinant erythropoietin (r-HuEPO, n = 36, 300 U/kg body weight) or placebo (n = 10) for 12 weeks in a multicenter study. An adequate response was defined as elevation of Hb≥120 g/l. Relevant clinical and laboratory assessments were made to evaluate efficacy and secure safety. A significant elevation in Hb from week 10 onwards was noted in twenty-six patients (five drop-outs) out of nine patients receiving placebo (one drop-out) (12±1.2 g/l vs 4±0.5 g/l; Hb elevation from 95 g/l to 107 g/l vs 93 g/l to 97 g/l, P<0.05). Only 14.6%, however, were considered responders according to preset criteria. In the responders a lower initial CRP, a significant reduction in ESR but not in CRP was seen compared to the remaining r-HuEPO group. A significant elevation of energy level was noted in the r-HuEPO group; otherwise, no differences in clinical variables were seen. No serious adverse effects were noted. When analyzing patients receiving oral iron in combination with r-HuEPO and adding five additional, openly selected patients receiving both adequate iron supplementation and r-HuEPO, there was a significant weekly elevation of Hb from week 8 onwards in favor of combination therapy over the ones only receiving r-HuEPO (18±1.1 g/l vs 7±1.1 g/l, P<0.05). The initial six responders had now reached ten of whom seven belonged to the combination therapy group. Response to r-HuEPO in RA patients appears to be dependent on availability of iron and on the degree of inflammation. If r-HuEPO treatment is considered, iron deficiency should always be corrected and strenous efforts should have been made to control the disease itself. Received: 21 February 1997 / Accepted: 21 April 1997  相似文献   
39.
目的:探讨生血宁片联合促红细胞生成素治疗维持性血液透析患者肾性贫血的临床效果。方法选取该院住院治疗的维持性血液透析肾性贫血患者60例,随机分为治疗组与对照组,治疗组患者给予促红细胞生成素联合生血宁片进行治疗,对照组患者给予促红细胞生成素联合蔗糖铁进行治疗。对两组患者治疗前后的贫血指标、临床治疗效果和不良反应进行对比分析。结果两组患者在治疗前的贫血指标之间差异无统计学意义(P>0.05),治疗后两组患者的贫血指标较治疗前有显著变化(P<0.05),治疗组患者治疗后较对照组贫血指标差异有统计学意义(P<0.05)。对照组患者通过治疗后的临床总有效率低于治疗组,两组之间差异有统计学意义(P<0.05)。对照组患者的不良反应率高于治疗组,两组患者之间差异有统计学意义(P<0.05)。对照组患者所使用的促红细胞生成素剂量明显高于治疗组,两组之间差异有统计学意义(P<0.05)。结论采取生血宁片联合促红细胞生成素治疗维持性血液透析患者肾性贫血的临床效果较为良好,且安全性较高,值得在临床治疗中应用。  相似文献   
40.
目的 探讨可作为预测增殖性糖尿病性视网膜病的危险因素.方法 选取2011年5月至2013年11月间在我院眼科怀疑为糖尿病视网膜病变患者168例作为研究对象,空腹抽取静脉血,送检验科实验室检测EPO、糖化血红蛋白、FBS、CRP水平、血脂、载脂蛋白A和B.采用t检验和x2检验、多因素logistic回归分析确定增殖性糖尿病性视网膜病发生的独立危险因素.结果 在怀疑为糖尿病视网膜病变患者168例中,测得患增殖性糖尿病性视网膜病患者28例,通过计算得出患者中增殖性糖尿病性视网膜病的患病率为16.67%.为了探讨PDR的危险因素,我们将全部PDR患者的可能危险因素纳入多因素logistic回归分析.结果表明,EPO(OR =0.31,95%CI:0.04~0.95,P=0.042)是预测增殖性糖尿病性视网膜病的独立危险因素.结论 血浆促红细胞生成素可作为预测增殖性糖尿病性视网膜病的危险因素.  相似文献   
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