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81.
Objective—Restenosis secondary to neointimal hyperplasia remains the major limiting factor after vascular interventions. Thrombin generated in high concentrations at the site of vascular injury plays a central role in thrombosis and hemostasis. Thrombin has also been implicated as a mitogen for smooth muscle cell proliferation that contributes to restenosis. This study was designed to determine the effects of a specific thrombin inhibitor on neointimal hyperplasia after balloon injury in a rat carotid artery model.

Design—A total of 47 male Sprague–Dawley rats were divided into five groups. All groups underwent balloon injury of the left carotid artery. A specific thrombin inhibitor, inogatran, was given in four different regimens: low and high dose injections, short‐term infusion for 3?h, and long‐term infusion for 1 week. After 2 weeks the animals were killed and the carotid neointima/media area ratio and the luminal narrowing were calculated.

Results—All treatments significantly reduced the neointimal hyperplasia. Inogatran given as a long‐term infusion for 1 week had the lowest neointima/media ratio compared with the other groups. The percentage of lumen narrowing was also significantly lower in all treatment groups compared with the control group.

Conclusion—A specific direct thrombin inhibitor, inogatran, reduces neointimal hyperplasia after arterial injury in rats. A more prolonged administration of the thrombin inhibitor gave a further reduction of the neointimal hyperplasia. It seems that inhibition of thrombin activity is not only important early after injury, but also later. This could have clinical implications in the treatment of restenosis and needs to be further evaluated.  相似文献   
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Low-dose (250 mg daily) oral probucol produces a significant antioxidant effect in coronary patients: increases activity of glutathione peroxidase (enzyme utilizing lipoperoxides) and reduces the content of free-radical oxidation products in the blood. Probucol therapy for 7 days before and for 6 months after coronary angioplasty significantly reduces the severity of coronary artery stenosis. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 144, No. 11, pp. 503–506, November, 2007  相似文献   
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目的分析自身免疫性早发性卵巢功能不全(POI)患者血清免疫指标水平,筛选出较为特异的免疫性指标。 方法选取46例自身免疫性POI患者(POI组)和46例健康女性(正常组),比较两组体液免疫指标、自身免疫指标、抗心磷脂综合征指标、甲状腺功能指标水平。 结果与正常组比较,POI组孕产次、经期及月经周期减少,卵泡刺激素、黄体生成素升高,雌二醇、抗苗勒氏管激素降低;体液免疫指标κ轻链、λ轻链、免疫球蛋白G、免疫球蛋白M、免疫球蛋白E升高,补体4降低;抗心磷脂综合征指标抗心磷脂IgA抗体(ACA-IgA)、ACA-IgG、抗β2糖蛋白1 IgM抗体升高;甲状腺功能指标游离三碘甲状腺原氨酸、游离甲状腺素、促甲状腺素受体抗体、甲状腺过氧化物酶抗体升高(P<0.05),上述指标阳性率两组间比较差异有显著性(P<0.05)。POI组内与自身免疫指标阳性率比较,体液免疫指标阳性率和甲状腺功能指标阳性率差异均有显著性。 结论自身免疫性POI患者血清体液免疫指标和甲状腺功能指标更容易发生异常。  相似文献   
84.
目的 对比分析晚期支架内再狭窄(in-stent restenosis, ISR)与无ISR患者的临床特点、血脂水平、载脂蛋白E (apolipoprotein E, ApoE)以及SLCO1B1基因的多态性,探讨影响晚期ISR的临床危险因素。方法 入选2018年1月至2020年12月住院行冠状动脉造影证实晚期ISR的患者共61例,另外入选行冠状动脉造影证实无晚期ISR的患者共119例为对照组。比较两组的临床特点、血脂水平以及ApoE以及SLCO1B1基因的多态性。所有患者根据低密度脂蛋白胆固醇(low-density lipoprotein cholesterol, LDL-C)水平分为<1.4mmol/l组,1.4~1.8 mmol/L组以及>1.8 mmol/L组,=比较不同组别晚期ISR的发生率。结果 晚期ISR组与无ISR组患者ApoE、SLCO1B1基因型以及等位基因的频率并无统计学差异(P>0.05),将不同基因型和等位基因频率分别进行组内两两对比,结果也无统计学差异(P>0.05)。两组患者总胆固醇(total cholesterol ,TC)、LDL-C、载脂蛋白B(apolipoprotein B, ApoB)、ApoB/ApoA比值以及非高密度脂蛋白胆固醇(non-high-density lipoprotein cholesterol, n-HDL-C)水平均有统计学差异,晚期ISR组上述指标均比对照组偏高(P<0.05)。3. <1.4 mmol/L组的ISR发生率为17.9%,1.4~1.8mmol/l组的ISR发生率为31.3%,>1.8 mmol/L组的ISR发生率为39.4%。不同LDL-C水平的组间总体ISR发生率并无统计学差异(P>0.05)。进一步行组间两两对比,小于<1.4mmol/l组的ISR发生率为与>1.8mmol/l组的ISR发生率有差异(P<0.05)。 结论 冠状动脉支架术后的患者,其ApoE或SLCO1B1的基因多态性与晚期ISR的发生率无明确关系。晚期ISR患者血脂水平较无ISR患者升高明显,将LDL-C降至1.4mmol/l以下可能有助于减少晚期ISR的发生。  相似文献   
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OBJECTIVE—To investigate changes in cytokine expression in the coronary circulation induced by percutaneous transluminal coronary angioplasty (PTCA).
METHODS—The study involved 32 patients with ischaemic heart disease who underwent elective PTCA for isolated stenotic lesions of the left coronary artery. Ten patients had plain old balloon angioplasty, 10 had percutaneous transluminal rotational atherectomy, and 12 had stent implantation. Blood samples were drawn from the coronary sinus before and immediately after PTCA. Plasma concentrations of interleukin 6 (IL-6), platelet derived growth factor (PDGF), monocyte chemoattractant protein 1 (MCP-1), and macrophage coronary stimulating factor (M-CSF) were measured. The patients were scheduled for follow up angiography six months after PTCA. Late loss index was calculated using quantitative coronary angiography.
RESULTS—IL-6 concentrations in coronary sinus blood increased immediately after PTCA (p < 0.001), but there was no change in PDGF, MCP-1, or M-CSF. There was a positive correlation between changes in IL-6 concentrations immediately after PTCA and late loss index six months after PTCA (r = 0.73, p < 0.001). IL-6 concentrations in coronary sinus blood were higher in patients with late restenosis than in those without restenosis (p < 0.001).
CONCLUSIONS—PTCA induces IL-6 production in the coronary circulation. This may induce subsequent inflammatory responses in injured vessels and play an important role in late restenosis after PTCA.


Keywords: inflammation; cytokine; restenosis  相似文献   
89.
BACKGROUND: Sirolimus-eluting stents (SES) have been demonstrated to reduce restenosis. However, there have been few studies evaluating the impact of renal insufficiency on the angiographic as well as clinical outcomes after SES implantation. METHODS: This study was composed of 304 consecutive patients having 361 lesions who underwent percutaneous coronary intervention with SES. The patients were divided into 3 groups according to renal function (group 1 [n = 204]; creatinine clearance (Ccr) > or = 60 ml/min, group 2 [n = 69]; Ccr < 60 ml/min, group 3 [n = 31]; hemodialysis). Clinical and angiographic follow-up were evaluated at 8 months. RESULTS: Clinical follow-up was obtained in all patients and angiographic follow-up was obtained in 283 patients (93.1%). Patients in group 3 showed a higher incidence of previous coronary artery bypass graft surgery, and there were more female gender, hypertensive, and less hyperlipidemia in this group. Late lumen loss at 8 months was significantly different among the 3 groups (group 1; 0.16 +/- 0.46 mm, group 2; 0.44 +/- 0.62 mm, group 3; 0.81 +/- 0.88 mm, P < 0.0001). Major adverse cardiac events (MACE) were documented in 22 patients (10.8%) in group 1, 13 patients (18.8%) in group 2, and 12 patients (38.7%) in group 3, respectively (P = 0.0002). CONCLUSION: Neointimal growth following SES implantation is more pronounced in patients with renal insufficiency, especially those undergoing dialysis, compared with patients with normal renal function. Regardless of the beneficial effect of SES, the increased risk of MACE mainly due to high incidence of target vessel revascularization in the subgroup of patients with renal insufficiency should be taken into account.  相似文献   
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