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81.
The purpose of this study was to establish the temporal stability of lipid responses to acute psychological stress. Eighteen men were tested twice an average of 16.2 months apart in identical laboratory reactivity protocols. Total cholesterol, triglycerides, high- and low-density lipoprotein-cholesterol, plasma volume, heart rate, and blood pressure were assessed during rest, serial subtraction, and speech. After correction for changes in plasma volume, significant elevations were recorded for all variables during the speech task, but fewer variables showed changes during the serial subtraction task. Strong intersession associations were found when considering levels of the variables during baseline and stress (rs≥58). Correlations for the change scores ranged from .36 to .52 for the atherogenic lipids and from .39 to .87 for the cardiovascular variables. Little evidence was found for stability of plasma volume changes. There is moderate to high temporal stability of the atherogenic lipids when considering rest and stress levels and small to moderate temporal stability when considering change scores.  相似文献   
82.
In 19 patients with different types of severe descensus, all without clinical evidence of stress incontinence, urethral stress pressure profiles and stress tests were done before and after repositioning of the prolapse. In 13 of the 19 patients, continence was artificial, because during repositioning they showed leakage of urine; however, 6 of the patients remained continent. The pressure transmission ratios decreased in different parts of the urethra in all the patients when repositioning with a gynecological speculum was done. The drop was most significant in those patients who lost urine after repositioning, showing poor urethral function. In women with genito-urinary prolapse, a test of urethral function is essential, even if there is no clinical evidence of incontinence after removal of the descensus. In cases of severe stress incontinence under this condition, a procedure for bladder neck stabilization should be added to routine prolapse surgery.  相似文献   
83.
本文报道2例肠梗阻和1例有机磷农药中毒患者出现暂时性高血糖症。该3例患者均无糖尿病史,因有重度失水,经大量补液纠正失水后血糖迅速恢复正常。口服葡萄糖耐量试验正常。作者认为非糖尿病患者可因重度失水而致应激性高血糖症。  相似文献   
84.
Malignant hyperthermia (MH) in humans is usually triggered by volatile anaesthetics and depolarizing muscle relaxants. However, other factors or drugs (e.g. cresol) are thought to induce MH. We report a case of fulminant MH associated with a ketoacidotic diabetic coma. After therapy for diabetic coma with insulin (containing the preservative cresol) and electrolyte solutions was started, the patient complained of increasing myalgia, developed a high fever and respiratory and metabolic acidosis and lost consciousness. MH was treated immediately with dantrolene; the patient recovered within 14 days. Five months later the patient was diagnosed as MH-susceptible by the in vitro caffeine and halothane contracture test. This case supports the assessment that MH and diabetes are associated diseases and that cresol could possibly trigger MH. Furthermore, therapy with dantrolene has been demonstrated to the beneficial in the treatment of MH associated with diabetic coma.  相似文献   
85.
 Previous studies using a reinstatement procedure have found that acute reexposure to the self-administered drug and exposure to footshock stress reinstate heroin and cocaine seeking after prolonged drug-free periods. Here we tested whether these findings generalize to alcohol-taking behavior. Male rats were initially allowed to consume alcohol in a two-bottle choice procedure (water versus alcohol) for 30 min/day for 36 days. Rats were then trained for 60 min/day in operant chambers to press a lever for the drug (0.13 ml of 12% w/v of an alcohol solution) for up to 55 days. After stable drug-taking on a fixed-ratio-3 schedule of reinforcement was obtained, lever pressing for alcohol was extinguished by terminating drug delivery for 4–9 days. Reinstatement of drug seeking was then determined after non-contingent priming injections of alcohol (0.24 and 0.48 g/kg; given IP and orally) or exposure to intermittent footshock stress (5 and 15 min; 0.8 mA). Priming injections of alcohol produced a modest dose-dependent reinstatement of drug seeking, whereas footshock stress potently reinstated extinguished alcohol seeking. In contrast, similar parameters of footshock failed to reinstate extinguished sucrose-taking behavior in rats previously trained to lever press for sucrose pellets. These findings extend previous reports on reinstatement of cocaine and heroin seeking by a footshock stressor and by priming drug injections. It also appears that the reinstatement procedure provides an appropriate methodology to study relapse to alcohol-taking behavior in the drug-free state. Received: 9 April 1997 / Final version: 1 August 1997  相似文献   
86.
This study examined comorbid psychiatric disorders in adolescents with bipolar disorder. Hospitalized bipolar adolescents (N=10) were compared to hospitalized adolescents with unipolar depression (N=33), and to adolescents with nonaffective psychiatric disorders (N=11). Results showed conduct disorder, attention-deficit hyperactivity disorder, psychosis, and having any DSM-III-R psychoactive substance use disorder were all significantly more common in the bipolar group than the unipolar depressed group. Comorbid anxiety disorder was present in 40–45% of the subjects in the unipolar and bipolar groups, but in none of the control group subjects. This study is supported in part by a grant to Dr. Borchardt from the University of Minnesota Graduate School.  相似文献   
87.
The locomotor stimulant effects of sustained administration of a potent and selective dopamine (DA) D-2 receptor agonist, [+]-4-propyl-9-hydroxynaphthoxazine (PHNO), in rats were assessed 24 h a day during 12 h light-dark cycles. PHNO was administered continuously with subcutaneous implants of Alzet osmotic minipumps (5 g/h), for 12 h a day with modified osmotic minipumps (5 g/h), or by daily injections (15 g, SC). Tolerance was observed to occur only with 24 h continuous infusions and only during the light period. The other treatment regimens produced sensitization of the locomotor response. Daytime tolerance to continuous infusions of PHNO was reversed following reversal of the light-dark cycle. A normally arousing stimulus also reversed (temporarily) daytime tolerance. The present results indicate that the temporal pattern of administration of DA agonists, the phase of the circadian cycle and environmental stimuli associated with arousal are important determinants of the behavioral consequences of long-term treatment.  相似文献   
88.
周雪丹  张科  吴卫  于明帅  吴晓红 《西部医学》2023,35(2):282-286+292
探讨麻醉诱导前给予右美托咪定对脊柱侧弯矫形术患者唤醒时间、镇痛效应及血流动力学的影响。方法 选取2021年1月~2021年12月间于我院行脊柱侧弯矫形术的患者113例为研究对象,按照简单随机法分为观察组(n=57)和对照组(n=56),观察组在麻醉诱导前给予0.8 μg/kg的右美托咪定10 min内静脉泵注体内,对照组在相同时间内泵入等量的生理盐水,而后两组患者均行全身麻醉,比较两组麻醉插管前(T0)、插管后10 min(T1)、唤醒前10 min(T2)、唤醒期间(T3)、唤醒后5 min(T4)、加深麻醉后10 min血流动力学指标[心率(HR)、平均动脉压(MAP)、血氧饱和度(SpO2)]变化,术后唤醒时间、唤醒质量、唤醒时躁动发生率,拔管即刻、术后2、6、24 h镇痛效果[视觉模拟评分法(VAS)],麻醉前、术后2 h及6 h应激反应[血清皮质醇(Cor)、醛固酮(ALD)、血糖(Glu)]水平及药物安全性。结果 HR、MAP组间、时间点、组间×时间点比较,差异均有统计学意义(P<0.05),观察组T3、T4时间段HR、MAP比较差异有统计学意义(P<0.05),SpO2组间、时间点、组间×时间点比较差异均无统计学意义(P>0.05)。观察组唤醒质量显著高于对照组(P<0.05),唤醒时躁动发生率显著低于对照组(P<0.05),两组唤醒时间比较差异无统计学意义(P>0.05)。VAS评分组间、时间点、组间×时间点比较,差异均有统计学意义(P<0.05),组内各时间段比较差异均有统计学意义(P<0.05),观察组术后2、6 h VAS评分显著低于对照组(P<0.05)。Cor、ALD、Glu组间、时间点、组间×时间点比较,差异均有统计学意义(P<0.05),组内各时间段内外周血Cor、ALD、Glu水平均依次递增(P<0.05),且观察组术后2、6 h外周血Cor、ALD、Glu水平均显著高于对照组(P<0.05)。观察组与对照组不良反应率比较,差异无统计学意义(2=0.154,P=0.694)。结论 脊柱侧弯矫形术麻醉诱导前给予右美托咪定有利于提高术中唤醒质量,降低术中血流动力学波动,改善术后疼痛及应激反应,具有良好的应用价值  相似文献   
89.
This article reports highlights from over 200 parents' observations of their preschoolers' play and verbalizations in the year following Hurricane Hugo. Commonly reported activities included reenactment and discussion of the event in multiple mediums, personification of Hugo, and expression of fears related to storms. Precocious concern for others, insight, and vocabulary were also noted. In these intact, relatively high functioning families, parents seemed able to facilitate their youngsters' adjustment without outside intervention.Portions of this report were presented in earlier form at the 1991 Society for Research in Child Development meeting in Seattle, Washington.  相似文献   
90.
Habitual smokers frequently report that when they are stressed smoking helps them to relax. One potential explanation for the reported stress ameliorating effect of smoking is that cigarette consumption (nicotine self-administration) may decrease the sympathetic autonomic nervous system activity which is associated with the stress response. In the present study, rabbits prepared with chronic vascular cannulae were used to study the effects of nicotine administation on plasma corticosterone, catecholamine (epinephrine, norepinephrine and dopamine) and glucose responses to physical restraint stress. Nicotine (0.025, 0.05 or 0.10 mg nicotine base/kg body weight) was administered for 10 days prior to the stress test to allow for the development of habituation/tolerance to its acute toxic effects. Independent administration of nicotine, or the application of the physical restraint stressor, resulted in increases in the plasma concentrations of corticosterone, epinephrine, norepinephrine, and glucose. Nicotine administration during restraint stress enhanced the increase in plasma corticosterone and epinephrine, as compared to the responses induced by either factor alone. The results suggest that the stress ameliorating effect of continued cigarette smoking, as reported by habitual smokers, is not due to a reduction in the activity of the peripheral sympathetic autonomic nervous system.  相似文献   
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