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121.
目的 建立麸炒白术Atractylodis Macrocephalae Rhizoma炮制全过程的定性判别模型,筛选出可以表征麸炒白术不同炮制程度的气味成分。方法 制备麸炒白术饮片,不同时间点取样进行分析。采用Heracles NEO超快速气相电子鼻采集气味图谱,与Arochembase数据库对比得到气味成分信息,结合峰面积分析气味成分的变化规律并进行化学计量学分析。结果 通过判别因子分析(discriminant factor analysis,DFA)、正交偏最小二乘-判别分析(orthogonal partial least squaresdiscriminant analysis,OPLS-DA)、层次聚类分析(hierarchical cluster analysis,HCA)等将麸炒白术炮制全过程样品成功分为4类:生品、炮制不及、炮制成品和炮制太过。在炮制过程中,3-甲基十五烷、十二烷基丙酸酯、正辛基环己烷、1,3-二硝基苯、8-甲基十五烷5个气味成分的峰面积占比较高,其中1,3-二硝基苯在炮制全过程中峰面积呈降低趋势;3-甲基十五烷从炮制不及到炮制成品的过程中峰面积呈增加... 相似文献
122.
123.
The effect of testosterone propionate (TP) on regeneration of the crushed hypoglossal nerve was studied in young adult rats. The TP treatment promoted axonal outgrowth as measured by an increase in the proportion of hypoglossal neurons labeled by retrograde transport of horseradish peroxidase injected into the tongue at selected postlesion periods compared with that in controls. The result indicated that TP exerts its effect on regeneration primarily by increasing the metabolic activity in hormone target neurons. The somatotopic organization of the hypoglossal nucleus and its projection into the major nerve branches were unaltered subsequent to crush injury. The maintenance of specificity was attributed to the intact perineurial and endoneurial sheaths which guided regenerating fibers to their original targets. 相似文献
124.
The effects of bilateral gonadectomy, testosterone replacement and cyproterone acetate treatment on seminal vesicle contractions were studied in rats in order to contribute new data on the role of androgens in the spontaneous motility of the seminal vesicle. In gonadectomized-testosterone treated rats the glands exhibited a spontaneous rhythmic activity similar to that of entire animals. The seminal vesicles of gonadectomized as well as of cyproterone treated rats also contracted spontaneously but the contractions showed a smaller amplitude. Such decrease could be related with the well-known atrophy and reduction in the number of smooth muscle cells occurring in seminal vesicles after castration. The results reported in this paper suggest that androgens are not required for the normal spontaneous activity of seminal vesicles. 相似文献
125.
本研究在前一阶段工作的基础上,进一步缩短了15-甲PGF_(2α)疗程和减少用药量,并以β-hCG放射免疫测定为主要指标,观察抗早孕效应。停经49天以内的60例早孕妇女随机分为两组,每组30例。组Ⅰ的15-甲PGF_(2α)最高用量为10毫克,组Ⅱ为8毫克;两组用药疗程均为8小时(比以前缩短4小时)。丙酸睾丸酮用法同前。结果两组抗早孕有效率分别为96.67%和100%(p>0.05);15-甲PGF_(2α)平均用量分别为9.67±0.21和7.70±0.19毫克(p<0.05)。组Ⅱ用药比组Ⅰ少2毫克,更适于门诊推广应用。本文并对β-hCG放射免疫测定在药物抗早孕研究中的应用及丙酸睾丸酮的抗早孕机理进行了讨论。 相似文献
126.
R. A. Charlwood G. M. Handberg J. N. Pennefather 《Clinical and experimental pharmacology & physiology》1979,7(1):11-21
1. Testosterone propionate (0·5 mg/day) administered for 5 weeks to prepubertal rats increased the weight of sex accessory organs but did not alter the rate of gain of body weight. Methandienone, given in a similar dosage regimen, was without effect on these parameters. The synthetic progestagen, norgestrel, administered orally in a dose of 0·5 mg/day increased the weight of the vas deferens but was without effect on seminal vesicle and testis weights and on the growth rate. Given in combination with testosterone, norgestrel caused a marked decrease in testis weight and reversed the effects of testosterone propionate on seminal vesicle weight. Thus, in the dosage regimen used, this progestagen exhibited an endocrine profile comprising androgenic, synandro-genic and anti-androgenic effects. 2. Rats, which were castrated when they weighed 70–80 g, exhibited rates of gain of body weight which were similar to those of control animals. Testosterone propionate in the doses used reversed castration-induced atrophy of the vas deferens and seminal vesicle. 3. The contractility of the vas deferens of intact rats, determined by direct field electrical stimulation, was unaffected by treatment with the steroids used in this study. However, there was a marked impairment of the contractility of the vas deferens following castration, which was not fully restored by testosterone propionate in the dosage regimen used. 4. The efficacies and potencies of the α-adrenoceptor agonists phenylephrine and 1-metaraminol in causing contraction of the vasa deferentia from intact rats were unaffected by the steroid treatments. In contrast, these agonists did not produce sustained, dose-dependent contractions of the vasa deferentia from castrated rats; however testosterone propionate fully restored the efficacy and potency of both agonists. 5. It is concluded from this study that although adequate testosterone levels are necessary for the maintenance of contractility in the rat vas deferens, the integrity of postjunctional adrenoceptors in not modified by a variety of steroid treatments. 相似文献
127.
Following injection of the acylating reagent N-succinimidyl [3H]propionate into the optic nerve of goldfish, labeled protein appeared in the ipsilateral retina and contralateral tectum in a time-dependent manner. Autoradiography indicated the presence of the labeled material in the neuroplasm of the retinal ganglion cells and their projections. While most of the recoverable injected radioactivity was confined to the injection site even after 1 week, labeled proteins arriving in the retina by retrograde flow or in the tectum by anterograde flow had distinctly different patterns, a result suggesting specific transport processes rather than diffusion. In contrast to reported studies with the labeling agent in other species, a prominent 68,000 molecular weight component was not seen. The results are dicussed in relation to the role of retrograde transport in regeneration. 相似文献
128.
《Nutrition reviews》1973,31(2):63-64
Rat glial cells cultured in vitamin B12 -deficient medium contained increased amounts of unbranched fatty acids with 15 and 17 carbon atoms, as well as increased levels of propionate. Addition of vitamin B12 to the medium caused the levels of the 15-and 17-carbon fatty acids to return to normal. These changes in the fatty acid composition of nerve cells of rats in vitamin B12 deficiency may be related to the neural lesions in vitamin B12 deficiency in human beings. 相似文献
129.
The inactivation of endogenous steroids and foreign compounds by the liver hydroxylative pathway, can be modified by androgenic substances. The inhibitory or inductory activity, can be estimated by measuring the half-life of antipyrine. Androgens (testosterone propionate, 5α-dihydro-testosterone and mesterolone) reduce antipyrine metabolism in male rabbits. In females, androgens are not inhibitors, but one of them, 5α-dihydrotestosterone, shows an inductive effect on liver oxidative mechanisms. 相似文献
130.
William W. Storms 《The Journal of asthma》1998,35(4):313-336
Benefits
Fluticasone propionate (FP) is a new topical corticosteroid spray for the treatment of allergic rhinitis and asthma. FP has been shown to be effective for the treatment of adult and pediatric asthma, even at rather low doses (25 μg twice daily [b.i.d.]); many studies in asthma have shown clinical efficacy of fluticasone at half the dose of the comparison steroid (such as beclomethasone dipropionate [BDP) or budesonide [BUD]). However, exact dose comparisons cannot be made because dose-ranging comparison studies have not been done. Studies in allergic rhinitis in children and adults have shown good efficacy in FP-treated patients at a dose of 200 μg once daily (o.d.), intranasally. In summary, FP is effective in both asthma and allergic rhinitis.
Risks
FP has minimal systemic activity because the portion of drug that is swallowed is not absorbed from the gut. Thus, the amount available for systemic activity is only that which is absorbed through the nasal mucosa (in the treatment of rhinitis) or through the alveoli of the lungs (in the treatment of asthma). When laboratory assays of adrenal function or bone formation are measured, FP and other inhaled corticosteroids can be shown to cause suppression of these markers, especially at high doses. There have been no consistent reports of clinical adrenal suppression or osteoporosis caused by FP.
In summary, the risk-benefit ratio of FP at the usual doses (therapeutic ratio) is very favorable. High doses may show evidence of suppression of the hypothalamic pituitary axis as measured by in vitro tests, but evidence of corresponding clinical adverse effects is lacking. 相似文献
Fluticasone propionate (FP) is a new topical corticosteroid spray for the treatment of allergic rhinitis and asthma. FP has been shown to be effective for the treatment of adult and pediatric asthma, even at rather low doses (25 μg twice daily [b.i.d.]); many studies in asthma have shown clinical efficacy of fluticasone at half the dose of the comparison steroid (such as beclomethasone dipropionate [BDP) or budesonide [BUD]). However, exact dose comparisons cannot be made because dose-ranging comparison studies have not been done. Studies in allergic rhinitis in children and adults have shown good efficacy in FP-treated patients at a dose of 200 μg once daily (o.d.), intranasally. In summary, FP is effective in both asthma and allergic rhinitis.
Risks
FP has minimal systemic activity because the portion of drug that is swallowed is not absorbed from the gut. Thus, the amount available for systemic activity is only that which is absorbed through the nasal mucosa (in the treatment of rhinitis) or through the alveoli of the lungs (in the treatment of asthma). When laboratory assays of adrenal function or bone formation are measured, FP and other inhaled corticosteroids can be shown to cause suppression of these markers, especially at high doses. There have been no consistent reports of clinical adrenal suppression or osteoporosis caused by FP.
In summary, the risk-benefit ratio of FP at the usual doses (therapeutic ratio) is very favorable. High doses may show evidence of suppression of the hypothalamic pituitary axis as measured by in vitro tests, but evidence of corresponding clinical adverse effects is lacking. 相似文献