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141.
目的 :黑色素瘤 B1 6细胞热休克蛋白 -抗原肽复合物 (HACs)及其粗提物 (HAC- CEs)的制备 ,以及它们的免疫原性和抑瘤效应的研究。方法 :应用 Sephacryl S- 2 0 0凝胶过滤制备HAC- CEs,应用亲和层析纯化 HACs,并测其免疫功能和抑瘤效应。结果 :应用凝胶过滤制备的HAC- CE3、HAC- CE4、HAC- CE5和应用亲和层析纯化的 HAC60 ,HAC75和 HAC97均不同程度地降低肿瘤发生率、延迟肿瘤发生时间和减少移植黑色素瘤 C57BL/6J小鼠死亡率 ;同时 ,伴有小鼠脾细胞 IFN-γ和 IL- 2分泌活性及 CTL杀伤率的增加。结论 :分子量为 60 0 0 0~ 970 0 0的 HACs具有免疫原性和抑瘤效应 ,本研究为制备肿瘤疫苗提供重要的实验依据。 相似文献
142.
袁莲珍 《武汉大学学报(医学版)》2000,21(3):250-251
目的 :探讨中西医结合治疗慢性牙周炎新方法。方法 :采用玉女煎加味方剂。结果 :中西医结合组治疗牙周炎总有效率为 93 75 % ,纯西药组为 81 2 5 % ,两组差异有显著性 (P <0 .0 1) 。结论 :中西医结合治疗慢性牙周炎价格便宜 ,可增加疗效 ,缩短病程。 相似文献
143.
丙肝宁对动物实验性肝损伤的保护作用 总被引:3,自引:1,他引:2
目的 研究中药复方丙肝宁的保肝作用。方法 采用D-Gal造成大鼠的急性肝损伤模型和CCI4所致慢性肝损伤模型。结果 丙肝宁2个剂量组对D-Gal造成大鼠的急性肝损僵模型和CCI4所致慢性肝损伤模型的血清酶活性均具有明显的抑制作用(P〈0.05,P〈0.01),病理检查结果表明,丙肝宁2个剂量组对D-Gal造成大鼠的急性肝损伤模型和CCI4所致慢笥肝损伤模型的肝脏病理形态的改变具有明显的改善作用。结 相似文献
144.
目的 评价中小学生大规模乙型肝炎疫苗接种效果。方法 随机选取来实行乙型肝炎疫苗计划免疫管理的6-18岁中小学生1829名,采用血清流行病学方法观测大规模酵母重组乙型肝炎疫苗接种效果。结果 对HBsAg、抗-HBs和抗-HBc全阴性者,接种疫苗1年后,抗-HBs阳性率为70.55%,HBsAg和抗-HBc阳性率分别为0.56%和1.96%;该人群接种前HBVM阳性率为63.31%,接种后为85.51%,抗-HBs阳性率显著增高,且以6-12岁低年龄组人群更明显,而HBsAg和抗-HBc阳性率在接种后1年无明显变化。结论 酵母重组乙型肝炎疫苗大规模接种后,在中小学生中形成了乙型肝炎高保护性、低感染状态。 相似文献
145.
146.
Methamphetamine use by women, even throughout pregnancy, is common. But there is limited knowledge about the effects in prenatally methamphetamine-exposed children. This study investigated how prenatal methamphetamine exposure in rats, via maternal i.v. self-administration, affected the sensitivity of adult offspring to methamphetamine in comparison with controls. The offspring were generated from dams either self-administering methamphetamine daily under limited-access conditions prior to and throughout pregnancy, or their respective saline-yoked control dams. Spontaneous and methamphetamine-induced locomotor activity was assessed in male and female offspring of both exposure groups after a range of methamphetamine doses. In a separate group of offspring, acquisition of i.v. methamphetamine self-administration, responding under fixed and progressive ratio schedules of methamphetamine reinforcement, and reinstatement of extinguished drug-seeking behavior were assessed. Methamphetamine dose-dependently increased locomotor activity in both exposure groups. However, methamphetamine-exposed males showed significantly enhanced locomotor activity compared with controls at 1 mg/kg, and methamphetamine-exposed females showed significantly enhanced locomotor activity compared with controls at 3.2 mg/kg. Methamphetamine-exposed offspring of both sexes acquired methamphetamine self-administration faster and showed overall higher levels of methamphetamine-induced reinstatement compared with controls. Taken together, these results indicate that prenatal methamphetamine exposure to relatively low levels alters methamphetamine sensitivity in male and female adult offspring. 相似文献
147.
妇科术后硬膜外腔注射吗啡镇痛效果观察 总被引:1,自引:0,他引:1
对妇科术后硬膜外腔注射吗啡镇痛效果进行观察分析探讨。对3a来我院使用术后硬膜外腔注射吗啡镇痛效果进行评定,对血压、脉博等情况观察进行总结分析。结果:硬膜外腔注射吗啡术后镇痛效果优85.6%,良6.8%。副作用有血压下降达27.8%、恶心呕吐15.5%,头晕23.0%。 相似文献
148.
单用国产紫杉醇治疗乳腺癌 总被引:22,自引:2,他引:20
目的评价国产紫杉醇(特素)对乳腺癌的治疗效果和不良反应。方法自1995年3月至1995年7月,采用紫杉醇治疗乳腺癌22例。紫杉醇175mg/m2(170.9~210.8mg/m2),21天为1个周期,共1~4次(中位数3次)。结果紫杉醇近期客观疗效:完全缓解3例,部分缓解11例,总有效率63.6%(14/22),有效患者的病情已全部再度进展,缓解期2~7个月(中位3.5个月)。特素化疗的主要不良反应为白细胞下降(96.2%)、脱发(100%)和肌肉疼痛(84.9%)。结论国产紫杉醇治疗乳腺癌有效,不良反应可以耐受。 相似文献
149.
The chemopreventive properties of soy isoflavonoids in animal models of breast cancer 总被引:8,自引:0,他引:8
Stephen Barnes 《Breast cancer research and treatment》1997,46(2-3):169-179
Genistein (5,7,4-trihydroxyisoflavone), one of two major isoflavonoids in soy, has anti-proliferative effects on mitogen-stimulated cell growth of human breast cancer cells in culture and is a candidate for use in the prevention of breast cancer. Soy protein preparations containing isoflavonoid conjugates have chemopreventive activity in carcinogen-induced rat models of breast cancer. Recent experiments in these models with purified genistein have revealed that the timing of the exposure of rats to this isoflavonoid is critical. Rats treated neonatally or prepuberally with genistein have a longer latency before the appearance of 7,12-dimethylbenz[a]anthracene-induced mammary tumors and a marked reduction in tumor number. The mechanism of genistein's preventive action is in part dependent on its estrogenic activity, which causes a more rapid differentiation of the cells of the mammary gland, analogous to the effects of an early pregnancy. Rats administered genistein after 35 days of age have smaller alterations in breast cancer risk, with a maximum reduction in mammary tumor number of 27%. In ovariectomized nude mice, dietary genistein increases cell proliferation of human breast cancer MCF-7 cell xenografts compared with a control diet. This estrogen-like effect of genistein is not observed in non-ovariectomized rats. Future studies on the anticancer potential of soy isoflavonoids should examine their interaction with other phytochemical components of soybeans and exploit newly developed animal models of breast cancer in which specific genes have been activated or inactivated. 相似文献
150.
M J Field R J Oles A S Lewis S McCleary J Hughes L Singh 《British journal of pharmacology》1997,121(8):1513-1522
- Gabapentin (neurontin) is a novel antiepileptic agent that binds to the α2δ subunit of voltage-dependent calcium channels. The only other compound known to possess affinity for this recognition site is the (S)-(+)-enantiomer of 3-isobutylgaba. However, the corresponding (R)-(−)-enantiomer is 10 fold weaker. The present study evaluates the activity of gabapentin and the two enantiomers of 3-isobutylgaba in formalin and carrageenan-induced inflammatory pain models.
- In the rat formalin test, S-(+)-3-isobutylgaba (1–100 mg kg−1) and gabapentin (10–300 mg kg−1) dose-dependently inhibited the late phase of the nociceptive response with respective minimum effective doses (MED) of 10 and 30 mg kg−1, s.c. This antihyperalgesic action of gabapentin was insensitive to naloxone (0.1–10.0 mg kg−1, s.c.). In contrast, the R-(−)-enantiomer of 3-isobutylgaba (1–100 mg kg−1) produced a modest inhibition of the late phase at the highest dose of 100 mg kg−1. However, none of the compounds showed any effect during the early phase of the response.
- The s.c. administration of either S-(+)-3-isobutylgaba (1–30 mg kg−1) or gabapentin (10–100 mg kg−1), after the development of peak carrageenan-induced thermal hyperalgesia, dose-dependently antagonized the maintenance of this response with MED of 3 and 30 mg kg−1, respectively. Similar administration of the two compounds also blocked maintenance of carrageenan-induced mechanical hyperalgesia with MED of 3 and 10 mg kg−1, respectively. In contrast, R-(−)-3-isobutylgaba failed to show any effect in the two hyperalgesia models.
- The intrathecal administration of gabapentin dose-dependently (1–100 μg/animal) blocked carrageenan-induced mechanical hyperalgesia. In contrast, administration of similar doses of gabapentin into the inflamed paw was ineffective at blocking this response.
- Unlike morphine, the repeated administration of gabapentin (100 mg kg−1 at start and culminating to 400 mg kg−1) over 6 days did not lead to the induction of tolerance to its antihyperalgesic action in the formalin test. Furthermore, the morphine tolerance did not cross generalize to gabapentin. The s.c. administration of gabapentin (10–300 mg kg−1), R-(−) (3–100 mg kg−1) or S-(+)-3-isobutylgaba (3–100 mg kg−1) failed to inhibit gastrointestinal motility, as measured by the charcoal meal test in the rat. Moreover, the three compounds (1–100 mg kg−1, s.c.) did not generalize to the morphine discriminative stimulus. Gabapentin (30–300 mg kg−1) and S-(+)-isobutylgaba (1–100 mg kg−1) showed sedative/ataxic properties only at the highest dose tested in the rota-rod apparatus.
- Gabapentin (30–300 mg kg−1, s.c.) failed to show an antinociceptive action in transient pain models. It is concluded that gabapentin represents a novel class of antihyperalgesic agents.