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61.
The Pittsburgh Sleep Diary   总被引:5,自引:3,他引:2  
SUMMARY  Increasingly, there is a need in both research and clinical practice to document and quantify sleep and waking behaviors in a comprehensive manner. The Pittsburgh Sleep Diary (PghSD) is an instrument with separate components to be completed at bedtime and waketime. Bedtime components relate to the events of the day preceding the sleep, waketime components to the sleep period just completed. Two-week PghSD data is presented from 234 different subjects, comprising 96 healthy young middle-aged controls, 37 older men, 44 older women, 29 young adult controls and 28 sleep disorders patients in order to demonstrate the usefulness, validity and reliability of various measures from the instrument. Comparisons are made with polysomnographic and actigraphic sleep measures, as well as personality and circadian type questionnaires. The instrument was shown to have sensitivity in detecting differences due to weekends, age, gender, personality and circadian type, and validity in agreeing with actigraphic estimates of sleep timing and quality. Over a 12–31 month delay, PghSD measures of both sleep timing and sleep quality showed correlations between 0.56 and 0.81 ( n = 39, P < 0.001).  相似文献   
62.
SUMMARY  Modafinil is an alerting substance that is considered safer than amphetamine with fewer side effects. Although modafinil has been used successfully to treat narcolepsy, relatively little is known about its ability to ameliorate fatigue and declines in mental performance due to sleep deprivation (SD) in a normal population. Forty-one military subjects received either 300 mg of modafinil, 20 mg of d-amphetamine, or placebo on 3 separate occasions during 64 hours of continuous cognitive work and sleep loss. Three drug treatments were given: at 23.30 hours and 05.30 hours during the first and second SD nights, respectively, and once at 15.30 hours during the third day of continuous work. Subjective estimates of mood, fatigue and sleepiness, as well as objective measures of reaction time, logical reasoning and short-term memory clearly showed better performance with both modafinil and amphetamine relative to placebo. Both modafinil and amphetamine maintained or increased body temperature compared to the natural circadian cycle observed in the placebo group. Also, from subject debriefs at the end of the study, modafinil elicited fewer side-effects than amphetamine, although more than the placebo group. Modafinil appears to be a good alternative to amphetamine for counteracting the debilitating mood and cognitive effects of sleep loss during sustained operations.  相似文献   
63.
SUMMARY  Animal and human studies have related the sleeping/waking brain to the immune system. Because women are more susceptible to certain immunological illnesses, and sex steroids regulate immune functions, it was investigated whether the diurnal sleep/wake pattern of aspects of cellular immune functions and interleukin-1 (IL-1) and IL-2-like activities differed during low and high progesterone phases of the menstrual cycle.
Eleven healthy women, mean age 24y, were assessed over 24h with serial venous blood samples. Peripheral blood monocytes were assayed for mitogen responses, i.e. phytohemagglutin (PHA) and pokeweed (PWM) and natural killer (NK) cell activities. Plasma was assayed for IL-1 and IL-2-like activities, cortisol and progesterone. Data were standardized by Z transformation and analysed by repeated-measures analysis of variance by comparing high ( N = 5) vs. low ( N = 6) progesterone phases.
During the high progesterone phase, delayed slow-wave sleep (SWS) onset time and reduced amount of SWS was accompanied by a delay in the decline of NK cell activity, but rise in PHA activity following sleep onset. With the low progesterone phase, the pattern was similar to men with an early sleep decline in NK cell and late sleep rise in PHA activities. PWM rose during the night and plasma IL-1-like activity peaked during midday and during nocturnal sleep irrespective of the amount of progesterone.
Slow-wave sleep and sleep-related NK cell and PHA activities differed over the menstrual cycle, but not PWM response. Increases in plasma IL-1 functions during midday and night are consistent with predisposition to sleepiness during these times.  相似文献   
64.
K-complexes: are they signs of arousal or sleep protective?   总被引:3,自引:2,他引:1  
SUMMARY  The number of K-complexes recorded at the central-temporal EEG derivation (C3-T3) during 5 min periods for both the ascending and descending phase of Stage 2 of NREM sleep for cycles 1,2… etc. were counted in 10 subjects for each of the following five groups: normal persons, patients with a primary generalized form of epilepsy, narcolepsy, insomnia and obstructive sleep apnoea. The differences in time spent in different stages of sleep were as expected for these types of patients. A 2-within, 1-between factors, repeated measure ANOVA was applied to the data on K-complexes. Overall, there was no significant difference between the number of K-complexes observed during the ascending and descending phases of the different sleep cycles. Patients with a sleep disorder had significantly less well-defined K-complexes than the normals and the patients with a primary form of generalized epilepsy: for insomnia ( P = 0.035), for apnoea ( P = 0.011) and for narcolepsy ( P = 0.001). There was a significant, but very low correlation coefficient between the number of K-complexes observed during Stage 2 of NREM sleep and the time spent during that stage for all groups combined (Rho 0.27, P = 0.002) and for the narcoleptic patients (Rho 0.44, P = 0.017). In all, the findings lend support to the hypothesis that a K-complex can be seen as a 'defensive response', or has a sleep protective function.  相似文献   
65.
The pineal hormone melatonin has clear circadian phase-shifting effects in humans which have recently been formalized as a phase response curve. Its potential use in circadian rhythm disorders has been investigated in field studies of jet lag and shift work and in simulated phase shift. A substantial amount of information indicates that in the majority of subjects it hastens adaptation of both subjective and objective measures to forced shifts in time cues with few reported side-effects. Field studies of its use in adaptation to shift work are sparse and preliminary but the first indications are positive. In some blind subjects with sleep disturbance it can stabilize sleep onset time without necessarily entraining all circadian rhythms and it can advance sleep timing in delayed sleep-phase insomnia. Acute suppression of core body temperature may be an integral part of the phase-shifting mechanism.  相似文献   
66.
Sleep, age, and shiftwork experience   总被引:4,自引:0,他引:4  
The effects of age and shiftwork experience (never, past, present) on sleep were studied in a sample of 3236 wage earners and retired workers by means of a questionnaire. The sample was composed of 32-, 42-, 52-, and 62-year-old subjects, and included both sexes and various occupational statuses. Age resulted in a continuously increasing frequency of sleep disturbances and hypnotic use, except for difficulty getting back to sleep and early awakening, which peaked at 52 years and then decreased at 62 years, thus suggesting a 'retirement effect'. Current and past shiftworkers reported more problems with falling asleep and early awakening than subjects who had never worked on shifts. This is a likely explanation of why the effect of age was massive in the latter group and much less pronounced in the former groups. There were no clear effects of the length or recency of shiftwork experience. This finding does not support the hypothesized permanent effect of shiftwork experience on subsequent sleep. Females had higher complaint rates at every age. There was little interaction between age and sex, but women were affected more by shiftwork as they got older, particularly as to hypnotic consumption. Some of the results support the hypothesis that a selection process excludes workers who are no longer able to cope with the demands of shiftwork.  相似文献   
67.
目的:探讨睡眠呼吸暂停综合征(SAS)患者夜间睡眠呼吸参数的变化及相应护理对策。方法:对16例SAS住院患者在治疗前、睡眠姿势训练、气道持续正压(CPAP)呼吸机治疗三种状态下,进行整夜多导睡眠仪监测。结果:在SAS整夜呼吸紊乱中,零点以后其危险因素大大增加,出现严重低氧血症,血压升高,心律失常,尤其是呼吸暂停时间延长,次数增加。而侧卧位可显著地改善低氧血症,最低血氧饱和度(SaO2)从(62±19)%升高至(83±11)%(P<0.01),CPAP呼吸机治疗能使呼吸调节障碍得到明显的恢复,呼吸暂停由(44.3±22.6)次降至(0.25±0.54)次(P<0.01)。结论:护理上应密切观察病情变化,特别是零点以后应加强巡视,除观察呼吸运动外还应警惕脑血管病及心脏疾病的发生,对不具备CPAP呼吸机治疗条件者宜采取睡眠时督促取侧卧位。对SAS患者进行健康教育也是减少危险因素的重要护理措施。  相似文献   
68.
The chewing of fresh leaves of the khat bush (Catha edulis) is common in certain countries of East Africa and the Arab peninsula, because this material has a stimulating effect. During the last decade, important progress has been made in understanding the pharmacology of this drug. Its actions are mainly due to the alkaloid cathinone, a substance that can be called a natural amphetamine.  相似文献   
69.
Summary Of 1302 women aged 44–66 years in a population study in Göteborg, Sweden, in 1974–75, who were representative of women of all the ages studied in the area, 165 were taking antihypertensive drugs, mostly -blockers and diuretics. The prevalence of sleep disturbances, nightmares, tiredness and melancholia or depression was studied in the total population sample, and a comparison was made between women who were or were not taking antihypertensive drugs. In the entire population sample no significant difference was found between the various age strata studied, although with increasing age there was a trend towards fewer complaints of nightmares, but a larger number of sleep disturbances as a whole. No difference was found between women taking or not taking various types of single-drug therapy or combinations of antihypertensive drugs.  相似文献   
70.
When exposed to an unfamiliar and sudden noise, infant rodents may show an abrupt bradycardia, as part of a "fear-paralysis response". The response is enhanced by body movements restraint. To investigate if this reaction is seen in humans, 15 normal infants with a median age of 12 weeks were studied polygraphically. They were exposed to a 100-dB (A) white noise, while sleeping in REM sleep. Each infant was studied in both "unrestrained" and "restrained" conditions. Restraint of body movement was obtained by means of sand bags and tightly-binding bed sheets. During movement restraint, the infants had a significantly greater and earlier decrease in heart rate compared with during the unrestrained condition. No infant had a minimal heart rate less than 95 beats/min. The present observation raises questions about the possible unfavorable effects of tightly wrapped bed sheets around sleeping infants.  相似文献   
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