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背景:Sauvegrain方法是通过分析肘部X线片来评估骨龄,常用于青春期生长发育最为迅速的两年间的骨龄测定。本文旨在研究该方法的准确性以及在小儿骨科中的应用价值。 方法:Sauvegrmn法主要评估肘部的4个解剖标志点:外髁、肱骨滑车、尺骨鹰嘴突以及桡骨近端骨骺。它是一个27分制的评分系统。对上述结构所得的评分进行合计而得出一个总分,然后使用标准图表确定骨龄。让三位观察者分别利用该方法进行骨龄评估。三位观察者通过分析60个男孩和60个女孩样本左肘部的前后位和侧位X线片来测定骨龄,并将该结果与通过分析左手和腕部后前位X线片的Greulich和Pyle图谱而得出的骨龄结果进行比较。间隔4周后每个观察者再测定骨龄一次。 结果:通过分析肘部X线片的方法测定骨龄更为精确,因为采用该方法测定骨龄可以精确到半岁。根据观察者的评定,Sauvegrain法显示出很好的观察者之间的相关性(r=0.93)和可重复性(r=0.96)。Sauvegrain法与Greulich和Pyle图谱之间有很好的相关性(r=0.85)。然而,一些肘部生长中心显示出一种中间的发育形态,这种形态学不适合Sauvegrain法的评分。这就导致了数据分析时出现误差。我们建议对于这些样本设定中间评分,并且通过修改原始图表而使评分更为精确。 结论:改良的Sauvegrain法简单、可靠而且可重复性高,它补充了Greulich和Pyle图谱的不足。在临床实践中,骨骼成熟度可以通过骨龄、年生长率以及第二性征而得以很准确的评估。因此,当青春期需要进行骨骺或脊柱关节融合术时,这种方法对于确定手术时间具有重要意义。 可信水平:诊断性研究,Ⅱ级,进一步可信度参见作者介绍。  相似文献   
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This paper examines application to the Family Fund by families with severely handicapped children and attempts to find out whether eligible families have basic knowledge of the fund, what motivates them to apply and why some eligible families do not apply. Five local registers are used to investigate levels of take-up and a Kent survey of families with severely subnormal children is used to examine the characteristics of non-claimants. The Kent survey is also used to investigate whether extra publicity promotes application and to identify reasons for non-take-up.  相似文献   
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The haemodynamic effects of nitrovasodilators and their mechanisms of action on portal hypertension remain unclear. The splanchnic and systemic haemodynamic response to the infusion of isosorbide dinitrate (100 μg/kg per min), a nitrovasodilator, was investigated in cirrhotic rats. The role of the conscious state in the haemodynamic response to isosorbide dinitrate was examined using rats that were anaesthetized with pentobarbitone. The role of sympathetic tone in the haemodynamic response to isosorbide dinitrate was examined using rats pretreated with the ganglion blocker hexamethonium. Isosorbide dinitrate had no haemodynamic effects in conscious, unblocked normal and cirrhotic rats. Isosorbide dinitrate had no haemodynamic effects in normal and cirrhotic rats treated with hexamethonium. In normal anaesthetized rats, isosorbide dinitrate significantly decreased systemic vascular resistance (414±25 vs 290±26 dyn.s/cm5 per 100 g). In cirrhotic anaesthetized rats, isosorbide dinitrate significantly decreased mean arterial pressure (98±6 vs 79±7 mmHg), systemic vascular resistance (318±30 vs 207±10 dyn.s/cm5 per 100 g), portal pressure (14.0±1.0 vs 11.3±0.9 mmHg) and portal territory vascular resistance (1362±163 vs 1031±182 dyn.s/cm5 per 100 g). In conclusion, this study shows that the portal hypotensive effects of isosorbide dinitrate depend upon the alterations of vascular tone by pentobarbitone.  相似文献   
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Chronic alcoholization by alcohol inhalation was used to studythe properties of magnesium, a non-competitive NMDA receptorantagonist, and CGP 39551, a competitive NMDA receptor antagonist,on behavioural dependence as estimated by the free-choice paradigm[alcohol 10% (v/v) vs. water], on the hypermotility after alcoholwithdrawal, and finally on the cortical vascularization. Thefirst experimental group received the drugs per os during thewhole alcoholization period. Magnesium (20 mg/kg/day) decreasedthe alcohol dependence while CGP 39551 (5 and 10 mg/kg/day)increased, in a dose-dependent manner, the dependence to alcohol.A second group of animals received the same drugs at the samedosages, not simultaneously during chronic alcoholization, butimmediately after alcoholization in one shot i.p. injection.In this case, rats receiving 5 mg/kg CGP 39551 never showedany dependence towards alcohol, while 10 mg/kg CGP 39551 or20 mg/kg magnesium prolonged the number of days of alcohol dependence.These results thus indicate the close interaction between NMDAreceptor function and dependence for alcohol. Magnesium hadno effects on hypermotility, while CGP 39551-treated animalspresented a decrease in the hypermotility observed after alcoholwithdrawal. Neither drug affected the hypervasculanzation accompanyingthe chronic alcoholization.  相似文献   
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Aprikalim is a potent, specific, and selective opener of ATP-sensitiveK+ (KATP) channels. By virtue of this pharmacological property,aprikalim affords cardioprotection in experimental models ofischemia/reperfusion injury, and, at higher doses, also causesperipheral or coronary vasodilatation. Direct-acting peripheralvasodilators can cause myocardial lesions, particularly in ratsand dogs. However, unexpectedly, aprikalim produced this effectalso in monkeys. Thus, the primary aim of this investigationwas to assess whether in monkeys these myocardial lesions werethe direct or indirect consequence of the vascular effects ofaprikalim. Cyno-mologus monkeys were given the ß-adrenoceptorantagonist nado-lol (2 mg/kg po, twice daily) for 4 consecutivedays. On the third and fourth day of the experiment, they receivedaprikalim (1 mg/kg po). In another series, two monkeys carryingtelemetry transmitters for blood pressure and heart rate measurementswere also given aprikalim or its vehicle. Finally, aprikalim(1 mg/kg po for 2 days) or its vehicle was administered to ratswhich were concurrently treated with the ß-adrenoceptorantagonist atenolol (5 mg/ kg sc) or its vehicle. In cynomologusmonkeys, aprikalim produced focal and multifocal myocardialnecrosis of minimal to moderate intensity in or near the papillarymuscles of the left ventricle. These effects were abrogatedby nadolol. Similarly, necrotic lesions were caused by aprikalimonly in those rats which had not been pretreated with atenolol.In monkeys, aprikalim produced a marked and long-lasting decreasein aortic blood pressure, accompanied by an even more prolongedtachycardia. These results demonstrate that aprikalim can producemyocardial necrosis not only in rats but also in monkeys. Toour knowledge, this is the first time that such adverse effectsare reported for a vasodilator in monkeys. More importantly,these effects were prevented by blocking cardiac ß-adrenoceptors.Thus, the myocardial lesions produced by aprikalim may be attributedto its profound and prolonged hemodynamic effects.  相似文献   
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Sulfamethazine (SMZ) was evaluated for reproductive toxicityin Swiss CD-1 mice using a continuous breeding protocol. SMZwas administered in the diet at 0, 0.25, 0.5, or 1% (w/w), whichrepresented an average daily intake of 0, 313, 625, or 1250mg SMZ/kg/day, respectively. Exposure of F0 male and femalemice to 1% SMZ for 126 days resulted in a significant decreasein the mean number of live pups per litter and the number oflitters produced (task 2); the percentage pups born alive to1% SMZ females showed a nonsignificant decrease versus controlfemales. The effects on fertility were rapid to onset (1 to4 weeks) and cumulative in nature. F0 male and female body weightswere slightly depressed from 3 weeks to the end of the study.The crossover mating trial (task 3) revealed that the adverseeffect on ferility involved both treated partners in that littersize decreased when either 1% SMZ males were bred to controlfemales or 1% SMZ females were mated with control males. Afterapproximately 155 days of exposure of F0 mice to 1% SMZ, theterminal body weight of 1% SMZ females was significantly decreasedand that of 1% SMZ males showed a nonsignificant decrease. Inaddition, the liver weight to body weight ratio of the maleswas increased. Further, the prostate and seminal vesicle weightto body weight ratios were decreased in 1% SMZ males relativeto control males. No treatment-related gross or histopathologicallesions were noted for the pituitary or reproductive organsof either sex. Sperm assessment indicated no significant differencein the epididymal sperm concentration or percentage motile orabnormal sperm. In conclusion, SMZ was found to be a reproductivetoxicant in the male and female Swiss CD-1 mouse, albeit atrelatively high dietary intake (1250 mg/kg/day), and in thepresence of mild systemic toxicity.  相似文献   
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Objective: To monitor key processes and outcomes in joint health and social services community psychogeriatric teams. Design: Six month follow-up of new referrals to 4 teams in Cambridge. Data collected from structured clinical assessment forms at baseline and interviews with keyworkers at follow-up. Data for groups with and without dementia were compared. Setting: Two rural and two urban teams in area with relatively large long stay inpatient facility but low independent sector provision. All were routine service teams, rather than run for research purposes. Main outcome measures: The main outcome measures were survival, institutionalisation, key worker assessments of avoidable admissions, appropriateness of placement, unmet needs, carer stress and global outcome for patient and carers. Results: Rates of referral to urban teams were double rural rates. Around forty percent of the dementia group had a social worker as assessor and keyworker. The dementia group was significantly more dependent and received more informal and formal care. After six months, only 54% of the dementia group were alive and living outside institutional care, compared to 79% in the functionally ill group. Unplanned admissions to hospitals or homes were rarely judged avoidable by keyworkers. Outcomes for carers were judged poor in 15% of both groups, and 13% and 11% of carers respectively were judged to be under severe stress. Unmet needs were more common in the dementia group, and related principally to residential care and carer respite. A number of measures, including evidence of geographical inequity and identification of unmet needs, provided an important contribution to local policy development. Further work is needed on the validity of keyworker assessments of carer stress, given the findings of the carer interview sub-study.  相似文献   
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