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31.
家兔隔区和伏核内钙、镁离子对抗电针镇痛与吗啡镇痛   总被引:1,自引:0,他引:1  
本文通过脑内慢性埋植套管向家兔一侧隔区或伏核内注射微量(10 nmol)CaCl_2或MgCl_2,可显著对抗吗啡镇痛和电针镇痛。注入核外则无效。家兔一侧隔区或伏核内注入阳离子螯合剂CDTA(20 nmol)加强吗啡镇痛和电针镇痛。文中就Ca~(2 ),Mg~(2 )作用的相似性,电针镇痛与吗啡镇痛机理的相似性,以及伏核和隔区在上述镇痛中的重要性进行了讨论。  相似文献   
32.
Cyclin-dependent kinase 5 (CDK5), a unique member of the CDK family of cyclin-dependent kinases, is predominantly expressed in postmitotic neurons with proposed roles in both cell survival and programmed cell death. To understand how CDK5 participates in such disparate cellular outcomes, we investigated whether activation of CDK5 could mediate neuroprotection from serum deprivation by mu-opioid receptor agonist in differentiated SH-SY5Y cells and primary hippocampal neurons. We found that CDK5 kinase activity decreased following serum deprivation in differentiated SH-SY5Y cells coincident with increased cell loss and activation of caspases cascade activation, which was reversed by opioid antagonist. Overexpression of CDK5 in serum-free medium reversed activation of caspase cascade and augmented DAMGO neuroprotection. Blocking CDK5 activity by pharmacologic inhibitor, roscovitine or overexpression of dominant negative CDK5 augmented activation of cell death markers and diminished mu-opioid receptor agonist protection. Reduction in CDK5 activity corresponded to reduction in protein levels of CDK5 activator p35 during serum deprivation which was also reversed by mu-opioid receptor agonist. Phosphorylation of STAT3 at Serine 727 by CDK5 decreased during serum deprivation, and partly recovered by mu-opioid agonist. PI3K signaling pathway was not required for CDK5-mediated mu-opioid neuroprotection against serum deprivation. These findings indicate that neuroprotection by mu-opioid receptor agonist against serum deprivation is mediated by activation of CDK5 through up-regulation of p35 and phosphorylation of STAT3 by CDK5 may contribute to the neuroprotection.  相似文献   
33.
Bone cancer pain has a strong impact on the quality of life of patients, but is difficult to treat. Better understanding of the pathogenic mechanisms underlying bone cancer pain will likely lead to the development of more effective treatments. In the present study, we investigated whether inhibition of KCNQ/M channels contributed to the hyperexcitability of primary sensory neurons and to the pathogenesis of bone cancer pain. By using a rat model of bone cancer pain based on intratibial injection of MRMT-1 tumour cells, we documented a prominent decrease in expression of KCNQ2 and KCNQ3 proteins and a reduction of M-current density in small-sized dorsal root ganglia (DRG) neurons, which were associated with enhanced excitability of these DRG neurons and the hyperalgesic behaviours in bone cancer rats. Coincidently, we found that inhibition of KCNQ/M channels with XE-991 caused a robust increase in the excitability of small-sized DRG neurons and produced an obvious mechanical allodynia in normal rats. On the contrary, activation of the KCNQ/M channels with retigabine not only inhibited the hyperexcitability of these small DRG neurons, but also alleviated mechanical allodynia and thermal hyperalgesia in bone cancer rats, and all of these effects of retigabine could be blocked by KCNQ/M-channel antagonist XE-991. These results suggest that repression of KCNQ/M channels leads to the hyperexcitability of primary sensory neurons, which in turn causes bone cancer pain. Thus, suppression of KCNQ/M channels in primary DRG neurons plays a crucial role in the development of bone cancer pain.  相似文献   
34.
Acupuncture increases brain levels of arginine-vasopressin (AVP) and oxytocin (OXT), which are known to be involved in the modulation of mammalian social behavior. Transcutaneous electrical acupoint stimulation (TEAS) is often used clinically to produce a similar stimulation to that of acupuncture on the acupoints. In the present study, TEAS was applied to children with autism to assess its therapeutic efficacy. Seventy-six autistic children receiving rehabilitation training were divided into 2 groups: a treatment group receiving TEAS 30min per day, 5 days per week for 12 weeks (n=37) and a control group without TEAS treatment (n=39). A series of rating scales was used in outcome assessment. Plasma levels of AVP and OXT were determined by enzyme immunoassay (EIA) before and after treatment. The TEAS group showed a significant improvement over the control in their emotional response, fear or anxiety, level/consistency of intellective relations and general impressions on the Childhood Autism Rating Scale (CARS) as well as improvements in the sensory and related factors in the Autism Behavior Checklist (ABC). In addition, the varieties of accepted food increased after TEAS treatment. It appears that TEAS was effective in autistic children who showed passive and aloof behavior, but not in those who were active but odd. The plasma level of AVP was significantly higher in the TEAS group than in the control group after the intervention. In addition, the change in the plasma AVP level paralleled the improvement of some of the behavior factors in CARS, including adaptation to environmental change, listening response, perceptive response and fear or anxiety. It is concluded that TEAS is effective for the treatment of autistic children with a passive and aloof social interaction style. Changes in plasma levels of AVP and possibly OXT may be involved in mediating the therapeutic effect of TEAS.  相似文献   
35.
目的 研究孕期暴露苯并(a)芘(B[a]P)对子代大鼠生理发育、早期行为发育、对环境的适应能力及学习记忆能力的影响.方法 SD孕鼠随机分为未处理对照组(每日正常饲养)、溶剂对照组(橄榄油)、低剂量组(25mg/kgB[a]P)、中剂量组(50mg/kgB[a]P)、高剂量组(100mg/kg B[a]P),于妊娠第17天开始,每天1次腹腔注射染毒,连续3 d,待其自然分娩.仔鼠出生后第1、4、7、14、28天称量体重,检测仔鼠生理发育、运动反射及感觉功能等发育指标,用Morris水迷宫试验和旷场试验分别评价仔鼠的学习记忆能力和对新异环境的适应能力.结果 与未处理对照组[(3.3±0.5)d]和溶剂对照组[(3.4±0.6)d]比较,中、高剂量组仔鼠张耳时间[(4.1±0.4)、(5.0±0.4)d]延长,差异有统计学意义(P<0.01).与未处理对照组(36、1%)相比,第4天高剂量组平面翻正试验达标率(6.5%)明显降低,与未处理对照组和溶剂对照组(81.3%、79.3%)相比,第7天时高剂量组仔鼠平面翻正试验达标率(50.0%)明显降低,差异有统计学意义(P<0.05).与未处理对照组比较,第12、14天时各染毒组仔鼠前肢悬挂时间均减少;与溶剂对照组比较,第14天时高剂量组仔鼠前肢悬挂时间减少,差异有统计学意义(P<0.01).与未处理对照组(94.3%)相比,第12天时高剂量组仔鼠嗅觉定向试验达标率(61.9%)明显降低,差异有统计学意义(P<0.05).Morris水迷宫试验结果表明,与未处理对照组和溶剂对照组比较,各剂量组仔鼠逃避潜伏期明显增加,高剂量组在目标象限停留时间和穿越平台次数减少,差异均有统计学意义(P<0.01).旷场实验结果表明,与未处理对照组[(2.40±0.89)、(82.2±15.9)、(17.4±3.9)s]比较,中、高剂量组仔鼠中央格停留时间[(9.67±1.53)、(12.80±3.77)s]明显延长,跨格次数(51.3±8.7、49.4±20.0)明显减少,高剂量组直立次数(8.0±2.6)明显减少,差异均有统计学意义(P<0.05);与溶剂对照组相比,各剂量组跨格次数明显减少,差异均有统计学意义(P<0.01,P<0.05).结论 孕期暴露B[a]P对仔鼠的生理发育、早期行为发育产生一定的抑制作用,并对仔鼠大脑学习记忆能力及其对新异环境的适应能力有一定影响.
Abstract:
Objective To study the effects of prenatal exposure to benzo[a]pyrene (B[a]P) on the physical development, early behavioral development, the adaptability to new environment and the learning and memory ability of rat offspring. Methods Pregnant rats were randomly divided into five groups: control group,olive oil group, 3 exposure groups (25, 50 and 100 mg/kg B [a]P). The rats were exposed to B [a]P) by intraperitoneal injection on the 17th-19th days during gestation. The offspring were weighed on postnatal days (PND)1, PND 4, PND 7 and PND 28, the indices of physical development, reflective ability and sensory function were detected for offspring, the Morris water maze and Open-field tests were used to measure the ability of learning and memory and the adaptability to new environment of offspring. Results The time of ear opening in middle and high-dose groups[(4. 1 ±0.4),(5.0±0.4) d] was posterior to that in untreated and solvent groups[(3.3±0.5),(3.4±0.6) d](P<0.01).The attainment rate (6.5%) of the surface righting reflex test in highdose group on the 4th day was significantly lower than that (36.1%) in untreated group, the attainment rate(50.0%) in high-dose group on PND7 was significantly lower than those (81.3% and 79.3%) in untreated group and solvent group (P<0.05). Compared to the untreated group, the time of forelimb hanging test in all exposure groups on PND12 and PND14 significantly decreased; compared to the solvent group the time of forelimb hanging test decreased in high-dose group on the 14th day significantly decreased (P<0.01). The attainment rate (61.9%) of olfactory discrimination in high-dose group on PND 12 was significantly lower than that (94.3%) in untreated group (P<0.05). The results of morris water maze test showed that the escape latency of different dose groups significantly increased, and the time of spatial probe and the times of traversing flat in high-dose group decreased significantly, as compared to the untreated and solvent groups(P<0.01). The results of open-field test indicated that the center retention time in middle and high-dose groups significantly prolonged, the times of crossing lattice obviously reduced, and the rearing times decreased in high-dose group,as compared to untreated(P<0.05).Compared to the solvent group, the times of crossing lattice in all exposure groups reduced significantly(P<0.01 or P<0.05). Conclusion The prenatal exposure to B[a]P could inhibit the physical development and early behavioral development, and influence the adaptability to new environment and learning and memory ability for offspring.  相似文献   
36.
目的:研究雌激素受体-α基因PvuⅡ和XbaⅠ多态性在广西壮、汉两民族中的分布。方法:采用PCR-RFLP方法检测壮族和汉族PvuⅡ和XbaⅠ多态性,比较其在两民族中的分布频率,并与其他种族的分布进行比较。结果:PvuⅡ等位基因P、p频率在壮族与汉族两个民族正常人群中分别为33.6%、66.4%和31.9%、68.1%;XbaⅠ等位基因X、x频率分别为22.4%、77.6%和24.2%、75.8%,在壮、汉两民族中比较差异均无显著性;与瑞典、韩国种族比较,PvuⅡ基因型分布及等位基因频率均存在显著差异。结论:雌激素受体-α基因PvuⅡ多态性与瑞典、韩国种族间分布有明显的差异。这种差异可能是导致一些疾病在不同种族、不同地区间的发生、转归和预后不同的遗传因素之一。  相似文献   
37.
目的探讨不同浓度氯化锂对染铅大鼠神经行为的影响。方法将大鼠随机分为对照组、染铅组、四个氯化锂组和四个铅+氯化锂组,分别给予普通饲料和含氯化锂(3,30,300和3000mg/kg)的饲料喂养,染铅组和四个铅+氯化锂组饮用体积分数0.2%PbAc2的单蒸水,喂养60d,通过测量大鼠体重和Y-迷宫实验,观察各组大鼠之间学习记忆能力的差别;采用黄递酶(NADPH-d)组织化学染色方法观察各组大鼠海马一氧化氮合酶(NOS)阳性细胞数的差别。结果氯化锂(3,30mg/kg)组大鼠体重增长多于对照组,Y-迷宫实验学会次数均少于对照组,差异均有显著性(P<0.05);氯化锂(300、3000mg/kg)组、染铅组体重增长少于对照组,Y-迷宫实验学会次数均多于对照组,差异均有显著性(P<0.05);与染铅组相比,铅+氯化锂(3,30,300mg/kg)组大鼠体重增量增加,Y-迷宫实验学会次数减少,差异有显著性(P<0.05)。NADPH-d组织化学染色结果示:氯化锂(3,30mg/kg)组大鼠海马一氧化氮合酶(NOS)阳性细胞数明显多于对照组(P<0.05);氯化锂(300、3000mg/kg)组、染铅组则少于正常大鼠(P<0.05);铅+氯化锂(3,30,300,3000mg/kg)组大鼠NOS阳性细胞数均多于染铅组(P<0.05)。结论较低浓度的氯化锂能促进正常大鼠学习记忆能力的提高,而较高浓度的锂则可能损害大鼠的学习记忆能力;铅暴露大鼠学  相似文献   
38.
Post-traumatic stress disorder (PTSD) is the serious psychiatric disorder. Paeoniflorin (PF) produces the antidepressant-like properties. However, few studies are concerned about its anti-PTSD-like effects and mechanisms. To investigate these, the single prolonged stress (SPS) model was utilized. PTSD-like behavioral deficits in rats after exposure to SPS were improved by PF (10 and 20 mg/kg, i.p.), evidenced by blocking increased freezing time in contextual fear paradigm (CFP) and increased time and entries in open arms in elevated plus maze (EPM) test without affecting the locomotor activity in open field (OF) test. We also found that increased levels of corticosterone (Cort), corticotropin releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) after exposure to SPS were reversed by PF (10 and 20 mg/kg, i.p.) in serum, respectively. Moreover, the decreased levels of serotonin (5-HT) and 5-Hydroxyindoleacetic acid (5-HIAA) in prefrontal cortex and hippocampus were reversed by PF (10 and 20 mg/kg, i.p.), respectively. In summary, the anti-PTSD-like activities of PF were associated with the modulation of HPA axis and 5-HT system activation.  相似文献   
39.
随着技术的进步,胰十二指肠切除术已逐渐在基层医院开展,该术式是治疗壶腹周围肿瘤及胰头癌的首选术式.壶腹周围及胰腺肿瘤极易累及周围的重要血管,意外损伤后如果处理不当可造成严重后果.因此,该术式是考验并且反映手术者对上腹部器官解剖、手术技巧以及处理术中突发事件的应变能力.因此,在胰十二指肠切除术发生重要血管意外损伤时,术者应当正确判断并掌握正确的紧急应对措施,尽量避免意外损伤造成术中死亡及术后并发症的发生.  相似文献   
40.
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