首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8823篇
  免费   789篇
  国内免费   552篇
耳鼻咽喉   15篇
儿科学   25篇
妇产科学   30篇
基础医学   208篇
口腔科学   80篇
临床医学   356篇
内科学   238篇
皮肤病学   119篇
神经病学   145篇
特种医学   172篇
外科学   212篇
综合类   1535篇
预防医学   200篇
眼科学   57篇
药学   5322篇
  14篇
中国医学   1295篇
肿瘤学   141篇
  2024年   28篇
  2023年   81篇
  2022年   158篇
  2021年   217篇
  2020年   223篇
  2019年   166篇
  2018年   198篇
  2017年   252篇
  2016年   287篇
  2015年   311篇
  2014年   632篇
  2013年   670篇
  2012年   763篇
  2011年   821篇
  2010年   613篇
  2009年   458篇
  2008年   570篇
  2007年   560篇
  2006年   485篇
  2005年   419篇
  2004年   388篇
  2003年   327篇
  2002年   241篇
  2001年   188篇
  2000年   192篇
  1999年   143篇
  1998年   87篇
  1997年   117篇
  1996年   87篇
  1995年   84篇
  1994年   57篇
  1993年   44篇
  1992年   40篇
  1991年   24篇
  1990年   23篇
  1989年   16篇
  1988年   19篇
  1987年   27篇
  1986年   19篇
  1985年   15篇
  1984年   16篇
  1983年   16篇
  1982年   14篇
  1981年   7篇
  1980年   12篇
  1979年   11篇
  1978年   5篇
  1976年   7篇
  1975年   5篇
  1973年   8篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
目的 建立高效液相色谱法测定蜂丁麻滴眼剂中盐酸麻黄碱含量的方法。 方法 采用YWGC18分析色谱柱 ( 4 6mmID× 2 5 0mm ,粒径 10 μm) ,C18保护柱 ( 4 6mmID× 5mm ,粒径 10 μm) ,流动相 10 %乙腈 ( 0 5 %三乙胺 ,磷酸调pH3 0 ) ,流速 1 0ml/min ,检测波长 2 0 8nm ,测定对照品和样品色谱图 ,记录盐酸麻黄碱色谱峰面积 ,计算其含量。 结果 盐酸麻黄碱的理论板数为 10 0 0 0。回归方程 :y =90 5 878 16 15 1738x ,r=0 9999,线性范围 0 4 0 32~ 1 6 13μg。平均回收率为 99 2 % (RSD1 6 % )。 结论 该法操作简便 ,结果准确 ,可用于测定蜂丁麻滴眼剂中盐酸麻黄碱的含量  相似文献   
32.
目的:研究原料药粒径等对盐酸普萘洛尔渗透泵片释药行为的影响。方法:取不同批号盐酸普萘洛尔及同批号重结晶前、后的原料药均按相同处方制备成渗透泵片,考察药物体外释放情况及释药24h后衣膜形态;并对上述不同原料药的粒径分别以光学显微镜和激光粒度分析仪进行证实。结果:以原料药粒径较小的渗透泵片释放完毕后衣膜变形,且不能维持零级释放,原料药粒径较大的渗透泵片结果与之相反。不同原料药经仪器证实粒径确有差异。结论:原料药的粒径可影响制备的渗透泵片的释放行为,提示性状稳定的原料药的合理选择在制剂过程中不可忽视。  相似文献   
33.
顶空—气相色谱法测定盐酸洛美利嗪中乙腈残留量   总被引:6,自引:1,他引:5  
目的:建立盐酸洛美利嗪原料药中乙腈残留量的测定方法。方法:采用顶空进样法,80%DMF水溶液为溶剂,平衡温度70℃,平衡时间40min,气相色谱条件:采用不锈钢填充色谱柱:柱长2m,内径3mm,粒径为0.25-0.32mm的二乙烯苯与乙基乙烯苯共聚物有机担体为填料,柱温130℃,FID检测器,检测器温度250℃,氮气为载气,流速50mL.min^-1。结果:乙腈在23.46-234.6μg.mL^-1的浓度范围内呈良好的线性关系(r=0.9978),回收率为96.7%(RSD=3.8%),检出限小于40μg.g^-1。结论:本方法简单,快捷且灵敏度高,可以用于盐酸洛洛美利嗪中乙腈残留量的控制。  相似文献   
34.
Pyoderma gangrenosum is a rare, chronic, inflammatory ulcerative skin disease of unknown etiology and pathogenesis. It is often associated with systemic disease. We describe a patient with pyoderma gangrenosum associated with ulcerative colitis and aseptic abscesses of the subcutis and spleen, which have been rarely reported previously. These manifestations were cleared by combined therapy with minocycline hydrochloride and diaphenylsulfone.  相似文献   
35.
卢日刚 《药学学报》1992,27(11):871-874
This paper provides a basic principle and experimental technique of derivative signal multiplier spectrophotometry in multicomponent mixture. A microcomputer was used to process the spectral data measured on a manual spectrophotometer (UV-7520) for the determination of moroxydine hydrochloride in Gan Mao Qing capsules. Quantitative analysis of multicomponent mixture can be done without sample separation. The selection of optimal wavelength pairs is performed through the program with a computer. The method needs no special spectrophotometer and is simple, rapid and easy to operate. The mean recovery was 99.98 +/- 0.53% (n = 12).  相似文献   
36.
应用反相HPLC法研究了复方盐酸右旋麻黄碱缓释片在兔体内动力学变化过程,并以自制普通片为对照,实验数据按单室模型采用非线性最小二乘法模型嵌合程序进行迭代处理。结果表明缓释片维持体内有效血药浓度时间长,其相对生物利用度为122.48%,理论值与实测值基本相符(P>0.05)。  相似文献   
37.
BACKGROUND: Olopatadine hydrochloride (olopatadine; Allelock) is one of the second-generation antihistamines that are treated for allergic disorders such as rhinitis, urticaria and eczema dermatitis. Olopatadine has recently been shown to have inhibitory effects on the chronic contact hypersensitivity induced by repeated application of oxazolone in mice. Although topical steroids have widely been prescribed for atopic dermatitis, a relapse often occurs within several days after discontinuation of their prolonged use. OBJECTIVES: We investigated the possible efficacy of olopatadine against the relapse after discontinuation of prolonged use of topical prednisolone in the Balb/c mice with oxazolone-induced chronic contact hypersensitivity. METHODS: Mice with the chronic contact hypersensitivity induced by repeated application of oxazolone were treated with olopatadine as a sequential therapeutic agent. The effects of olopatadine were quantified by measurements of ear-swelling, and levels of cytokines and histamine in the lesioned ear. Results Topical prednisolone (0.05 mg/ear/day) significantly inhibited the increases in ear swelling and production of IL-1beta, IL-4, IL-18, granulocyte-macrophage colony-stimulating factor (GM-CSF) and histamine. However, after discontinuation of the treatment with topical prednisolone, the inflammation relapsed and the IL-4 level exceeded the control one. The sequential treatment with olopatadine (10 mg/kg/day) after discontinuation of the treatment with topical prednisolone alone, or topical prednisolone with olopatadine, significantly inhibited the increases in ear swelling and levels of IL-1beta, IL-4, IL-18, GM-CSF, nerve growth factor and histamine. CONCLUSIONS: These results indicate that olopatadine is an antihistamine agent having inhibitory activities against the rebound phenomenon following the discontinuation of topical steroid therapy. Olopatadine is thus expected to be a sequential therapeutic agent after discontinuation of the chronic treatment with a topical steroid.  相似文献   
38.
目的 :考察 1 %盐酸丁卡因滴眼液的稳定性 ,确定其有效贮存期。方法 :采用经典恒温法预测其有效期。结果 :经典恒温法[1 ] 预测室温贮存期约为 2 0d ,冰箱贮存期约为 1 1 0d。结论 :该制剂对热不稳定 ,应冷藏。  相似文献   
39.
BACKGROUND: Sevelamer hydrochloride was recently proposed as a phosphate binder to prevent hypercalcaemia in place of calcium alkaline salts in dialysis patients. So far, it has been evaluated only in patients receiving calcitriol, without comparison with CaCO(3) alone, although the latter was found to be as effective as the combination of calcitriol and Al(OH)(3) in suppressing parathyroid hormone (PTH) without inducing hypercalcaemia and to have a better lowering effect on serum phosphate. Moreover, this bile salt binder may decrease serum 25-OH vitamin D. Therefore, we compared for 5 months two strategies for controlling moderate hyperparathyroidism: CaCO(3) alone vs sevelamer in conjunction with measures to increase calcium balance. METHODS: Forty-two patients were randomized: 21 continued their treatment with 4.8 g/day CaCO(3) and 21 were switched to sevelamer (initial dose: 2.4 g/day, increased to 4.4 g/day). Each month, when serum-corrected calcium decreased below 2.30 mmol/l, dialysate calcium was increased or alphacalcidol was given at each dialysis session, according to serum PO(4) levels. The following parameters were monitored: serum Ca, PO(4), bicarbonate and protein, weekly; and serum PTH, 25-OH vitamin D and total, LDL and HDL cholesterol monthly. RESULTS: Except for higher serum phosphate at month 1, lower serum bicarbonate at month 2 and lower LDL cholesterol at month 5 in the sevelamer group, no difference was found between the two groups. Compared with baseline levels, PTH increased and 25-OH vitamin D decreased significantly in both groups, these two parameters being inversely correlated. CONCLUSIONS: Given comparable control of plasma calcium, phosphate and 25-OH vitamin D, PTH control is comparable in both strategies. Sevelamer does not induce greater vitamin D depletion than CaCO(3). The transient decrease of serum bicarbonate after discontinuation of CaCO(3) in the sevelamer group suggests a less optimal prevention of acidosis. The sevelamer-induced decrease in LDL cholesterol gives this drug a potential advantage in cardiovascular prevention.  相似文献   
40.
目的研究抗胆碱新药盐酸三环哌酯(TCPN)在小鼠体内的药代动力学及组织分布。方法药代动力学采用放射受体分析法研究,组织中的分布用放射同位素分析法研究。结果小鼠scTCPN后,血液中药物浓度的经时过程符合一级吸收二室模型(T1/2β为2.28h,Tmax为0.125h,Cmax为3.44μg·L-1,Cl为23.0L·kg-1·h-1)。小鼠sc[3H]-TCPN后,分布高峰放射性依次为肾>肝>脑>颌下腺>肠1998-04-03收稿,1998-07-26修回*国家自然科学基金资助课题,No39130090-2作者简介:葛召恒,男,32岁,硕士,助理研究员;阮金秀,男,62岁,研究员,博士生导师,中国毒理学会副理事长,中国药理学会药物代谢专业委员会主任委员>心>肌肉,唯有脑组织的放射性以较高的水平维持较长的时间。预先给小鼠sc不同剂量的QNB,可不同程度地降低脑中放射性的分布。结论TCPN从血中的消除较快,但在脑组织分布时间长,这与药物与脑中M受体的特异性结合有关。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号