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91.
Osteoarthritis (OA) is a progressive joint disorder which affects cartilage and subchondral bone. Calcitonin gene‐related peptide (CGRP) plays a role in bone metabolism. The purpose of this study is to examine the therapeutic effect of the blocking CGRP on OA progression in mice by inhibition of subchondral bone sclerosis. OA was induced by the resection of the medial meniscotibial ligament of the knee in C57/BL6 mice. An intraperitoneal injection of the CGRP receptor antagonist (BIBN4096) was administered after OA surgery. At 1, 4, and 8 weeks after injection, histological analysis were performed. In vitro, the effect of CGRP and BIBN4096 on osteogenesis and osteoclastogenesis was analyzed. BIBN4096 could prevent cartilage degeneration and subchondral bone sclerosis. The OARSI score in the BIBN4096 group was significantly lower than that in the control. In vitro, CGRP up regulated osteocalcin expression, but its expression was down regulated by BIBN4096. CGRP inhibited osteoclastogenesis of raw 267.4 cells, but its effect was reduced by the addition of BIBN4096.The current study showed that subchondral bone sclerosis and increasing expression of CGRP occurs in the early phase of OA in relation to cartilage degeneration, and that BIBN4096 could effectively attenuate OA progression. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1177–1184, 2016.  相似文献   
92.
Neuro‐immune interactions, particularly those driven by neuropeptides, are increasingly implicated in immune responses. For instance, triggering calcium‐channel transient receptor potential vanilloid 1 (TRPV1) on sensory nerves induces the release of calcitonin‐gene‐related peptide (CGRP), a neuropeptide known to moderate dendritic cell activation and T helper cell type 1 polarization. Despite observations that CGRP is not confined to the nervous system, few studies have addressed the possibility that immune cells can respond to well‐documented ‘neural’ ligands independently of peripheral nerves. Here we have identified functionally relevant TRPV1 on primary antigen‐presenting cells of the spleen and have demonstrated both calcium influx and CGRP release in three separate strains of mice using natural agonists. Furthermore, we have shown down‐regulation of activation markers CD80/86 on dendritic cells, and up‐regulation of interleukin‐6 and interleukin‐10 in response to CGRP treatment. We suggest that dendritic cell responses to neural ligands can amplify neuropeptide release, but more importantly that variability in CGRP release across individuals may have important implications for immune cell homeostasis.  相似文献   
93.
Dux M  Rosta J  Pintér S  Sántha P  Jancsó G 《Neuroscience》2007,150(1):194-201
Neuropathic alterations of sensory nerves involved in the mediation of neurogenic inflammation of the meninges may contribute to the increased incidence of headaches in diabetics. In the rat, activation of capsaicin-sensitive nociceptors, which express the transient receptor potential vanilloid type 1 (TRPV1) receptor, induces meningeal vasodilatation, a significant component of neurogenic inflammation, through the release of calcitonin gene-related peptide (CGRP). This study examines the effects of streptozotocin-induced diabetes on TRPV1 receptor-mediated neurogenic sensory vasodilatation, CGRP release and nerve fiber density in the rat dura mater. In a cranial window preparation, epidural application of capsaicin (10(-7) M) produced distinct vasodilatory responses in control animals as measured by laser Doppler flowmetry. In diabetic rats, capsaicin-induced vasodilatation was reduced or even abolished 6, but not 2 or 4 weeks after diabetes induction. In contrast, vasoconstriction, a non-neurogenic response to capsaicin at a higher concentration (10(-5) M), was not altered in diabetic rats. The vasodilatory effects of histamine (10(-5) M), acetylcholine (10(-4) M) and CGRP (10(-5) M) were similar in control, diabetic and insulin-treated diabetic animals. In diabetic rats, a significant decrease in the capsaicin-evoked release of CGRP and reduction in the density of TRPV1-immunoreactive (IR) nerves were demonstrated. Treatment of the diabetic rats with insulin restored both the vasodilatory response and the capsaicin-induced CGRP release toward control values. In conclusion, this study revealed a marked impairment of meningeal TRPV1-IR nerves in streptozotocin diabetic rats by showing reduced neurogenic sensory vasodilatation, decreased capsaicin-evoked CGRP release and reduction in the number of TRPV1-IR nerve fibers of the dura mater. The findings suggest that capsaicin-sensitive afferents may play an important role in meningeal nociceptor function and their dysfunction, e.g. due to a limited removal of inflammatory mediators and/or tissue metabolites from the meningeal tissue, may contribute to the enhanced incidence of headaches in diabetics.  相似文献   
94.
The present study was designed to investigate involvement of angiotensin II (Ang II) type 2 receptors (AT2 receptors) in restoration of perivascular nerve innervation injured by topical phenol treatment. Male Wistar rats underwent in vivo topical application of 10% phenol around the superior mesenteric artery. After phenol treatment, animals were subjected to immunohistochemistry of the third branch of small arteries, Western blot analysis of AT2 receptor protein expression in dorsal root ganglia (DRG) and studies of mesenteric neurogenic vasoresponsiveness. Ang II (750 ng/kg/day), nerve growth factor (NGF; 20 microg/kg/day) and PD123,319 (AT2 receptor antagonist; 10 mg/kg/day) were intraperitoneally administered for 7 days using osmotic mini-pumps immediately after topical phenol treatment. Losartan (AT1 receptor antagonist) was administered in drinking water (0.025%). Phenol treatment markedly reduced densities of both calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI) and neuropeptide Y (NPY)-LI-containing fibers. NGF restored densities of both nerve fibers to the sham control level. Coadministration of Ang II and losartan significantly increased the density of CGRP-LI-fibers but not NPY-LI-fibers compared with saline control. The increase of the density of CGRP-LI-fibers by coadministration of Ang II and losartan was suppressed by adding PD123,319. Coadministration of Ang II and losartan ameliorated reduction of CGRP nerve-mediated vasodilation of perfused mesenteric arteries caused by phenol treatment. The AT2 receptor protein expression detected in DRG was markedly increased by NGF. These results suggest that selective stimulation of AT2 receptors by Ang II facilitates reinnervation of mesenteric perivascular CGRP-containing nerves injured by topical phenol application in the rat.  相似文献   
95.
Our previous report showed that innervation of calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-containing nerves in rat mesenteric resistance arteries was markedly reduced by topical application of phenol, and that nerve growth factor (NGF) facilitates the reinnervation of both nerves. We also demonstrated that a CGRP superfamily peptide, adrenomedullin, is distributed in perivascular nerves of rat mesenteric resistance arteries. In the present study, we investigated the influence of adrenomedullin on the reinnervation of mesenteric perivascular nerves following topical phenol treatment. Under pentobarbital-Na anesthesia, 8-week-old Wistar rats underwent in vivo topical application of phenol (10% phenol in 90% ethanol) to the superior mesenteric artery proximal to the bifurcation of the abdominal aorta. After the treatment, the animals were subjected to immunohistochemistry of the third branch of small arteries proximal to the intestine and to vascular responsiveness testing on day 7. Topical phenol treatment caused marked reduction of the density of NPY-like immunoreactive (LI)- and CGRP-LI nerve fibers in the arteries. Adrenomedullin (360 or 1000 ng/h) or NGF (250 ng/h), which was administered intraperitoneally for 7 days using an osmotic mini-pump immediately after topical phenol treatment, significantly increased the density of CGRP-LI- and NPY-LI nerve fibers compared with saline. Treatment with adrenomedullin (1000 ng/h) or NGF restored adrenergic nerve-mediated vasoconstriction and CGRP nerve-mediated vasodilation in the perfused mesenteric artery treated topically with phenol. These results suggest that adrenomedullin, like NGF, has a facilitatory effect on the reinnervation of perivascular nerves.  相似文献   
96.
目的 :探讨高氧液对缺血大鼠脑细胞的保护作用。方法 :40只 Wistar大鼠 (雌雄各半 )随机分成高氧液组、对照组、模型组和假手术组 ,每组各 10只。阻断 3条动脉造成急性不完全性脑缺血 ,制备动物模型。制模成功后 ,高氧液组立即以 10 ml· kg- 1 · h- 1 的速率经尾静脉输入高氧液 ,对照组以同种方法输入等量生理盐水 ,模型组和假手术组不治疗。制模后 1小时各组动物经腹主静脉取血 ,然后立即断头取脑 ,测定内皮素 (ET)和降钙素基因相关肽 (CGRP)含量。结果 :高氧液可明显降低脑缺氧后 ET水平 ,而升高 CGRP水平 ,纠正 ET、CGRP失衡。结论 :高氧液对缺血大鼠脑细胞有明显保护作用。  相似文献   
97.
目的探讨甲状旁腺素联合降钙素对大鼠骨质疏松性骨折骨相关生长因子及骨折愈合的影响。方法75只雌性SD大鼠随机分为:假手术组、去势组、甲状旁腺素组、降钙素组、联合用药组,15只/组,首先构建去卵巢大鼠骨质疏松性骨折动物模型。观察并评估骨折愈合,测定骨痂BMD和BMC,检测血清BMP-2、VEGF、TGF-β、IGF-1水平和骨痂蛋白表达,观察骨痂形态结构变化。结果去势组较假手术组骨折愈合评分、骨痂BMD和BMC、血清BMP-2、VEGF、TGF-β、IGF-1水平和骨痂蛋白表达均显著降低(P均<0.05),而联合用药组较去势组上述指标均显著升高(P均<0.05)。去势组骨痂骨小梁明显减少,生长稀疏,排列紊乱,大量间充质干细胞及纤维软骨细胞,成骨细胞及微血管少见;联合用药组骨痂大量骨小梁,生长旺盛,互相交错网状,排列致密有序,可见较多成熟的骨细胞及成骨细胞。结论甲状旁腺素联合降钙素通过介导提高相关骨生长因子表达,提高骨质疏松性骨折骨密度和矿物含量,改善骨组织形态学,加快骨折愈合。  相似文献   
98.
目的 分析甲状腺髓样癌(MTC)手术切除范围及预后影响因素。方法 回顾性分析2015年1月至2017年6月期间首诊于天津医科大学肿瘤医院MTC病人的临床资料。分析临床病理特征与中央区、侧颈区淋巴结转移及生化治愈的关系;探讨影响病人无进展生存期的危险因素。结果 77例病人,术前降钙素水平正常者5例,升高者72例。行全甲状腺切除28例,单侧腺叶切除49例。仅行中央区淋巴结清扫39例,中央区及患侧侧颈淋巴结清扫38例。MTC病人中央区淋巴结转移与性别、侵出腺叶、肿瘤直径、TNM分期、术前降钙素、降钙素水平/肿瘤直径具有相关性(P<0.05)。侧颈淋巴结转移与年龄、TNM分期具有相关性(P<0.05)。生化治愈率66.1%(39/59),与中央区淋巴结转移、TNM分期、肿瘤直径、术前降钙素水平及降钙素水平/肿瘤直径具有相关性(P<0.05)。中位随访时间35(7~69)个月。侵出腺叶、中央区淋巴结转移、淋巴结转移、淋巴结切除范围、TNM分期、术前降钙素水平和生化治愈是MTC病人无进展生存期的影响因素(P<0.05)。结论 MTC病人建议至少行患侧腺叶切除及中央区淋巴结清扫,必要时行全甲状腺切除,根据超声、CT及降钙素水平等检查结果行预防性/治疗性侧颈淋巴结清扫。规范化的手术治疗是达到较高生化治愈率,减少复发的关键。  相似文献   
99.
家族性甲状腺髓样癌(FMTC)作为甲状腺髓样癌(MTC)的一个重要分型,恶性程度较高,具有早期侵犯区域淋巴结和远处转移的倾向,预后相对较差,且有发病率不断增高的趋势。近年来关于FMTC临床的诊断和治疗进展较多,血清降钙素水平检测、基因检测等诊断方法提供了更精准的术前评估与复发监测的手段;疾病早期,根治性手术治疗仍占FMTC治疗的主要地位。根据基因检测的结果,进行预防性甲状腺切除以及分子靶向治疗也得到了快速的发展和应用,使传统手术与新兴治疗方法相结合,进一步提高了FMTC的治疗效果。  相似文献   
100.
目的探讨鲑鱼降钙素鼻喷剂结合脉冲电磁场治疗仪治疗骨质疏松性腰痛的临床疗效。方法选择2012年12月-2014年6月期间收治的骨质疏松性腰痛患者78例并按照随机数字表法分组为对照组和观察组,每组39例。对照组采用鲑鱼降钙素鼻喷剂治疗,观察组采用鲑鱼降钙素鼻喷剂结合脉冲电磁场治疗仪治疗。观察两组患者治疗前后疼痛评分情况及不良反应。结果治疗前观察组患者疼痛评分为(6.67±1.02)分与对照组(6.71±1.03)分比较,差异无统计学意义(P〉0.05)。治疗后观察组患者疼痛评分为(1.47±0.36)分,对照组为(3.69±0.53)分,两组患者均出现明显下降,但观察组优于对照组(P〈0.05)。此外,观察组不良反应率为2.56%(1/39)明显低于对照组10.26%(4/39)(P〈0.05)。结论骨质疏松性腰痛患者采用鲑鱼降钙素鼻喷剂结合脉冲电磁场治疗仪治疗,可有效缓解患者疼痛,且不良反应少。  相似文献   
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