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101.
Transcranial magnetic stimulation (TMS) is a diagnostic and therapeutic modality that is being developed as both an acute and preventive treatment for migraine. TMS delivers a fluctuating magnetic field from the scalp surface to induce current in the subjacent cortex. Magnetic pulses are delivered one at a time in single-pulse TMS (sTMS) or as a train of pulses in repetitive TMS (rTMS). For most of its 30-year history, TMS has been delivered in clinical and research settings using large tabletop devices. Based on the theory that sTMS may disrupt cortical spreading depression, sTMS has been studied and shown to be effective as an acute treatment for migraine with aura. Subsequent work in animal models confirms that sTMS disrupts cortical spreading depression. To make outpatient self-treatment possible, a portable device has been developed for acute treatment of migraine with aura. Based on the theory that rTMS alters brain excitability and neurotransmitter activity, rTMS has been studied as a preventive migraine treatment. A small body of evidence suggests that rTMS may have a role, but further studies are needed. In this review, we summarize the data on TMS as a treatment of migraine, and we suggest directions for future research.  相似文献   
102.
Later‐life changes in brain tissue volumes—decreases in the volume of healthy grey and white matter and increases in the volume of white matter hyperintensities (WMH)—are strong candidates to explain some of the variation in ageing‐related cognitive decline. We assessed fluid intelligence, memory, processing speed, and brain volumes (from structural MRI) at mean age 73 years, and at mean age 76 in a narrow‐age sample of older individuals (n = 657 with brain volumetric data at the initial wave, n = 465 at follow‐up). We used latent variable modeling to extract error‐free cognitive levels and slopes. Initial levels of cognitive ability were predictive of subsequent brain tissue volume changes. Initial brain volumes were not predictive of subsequent cognitive changes. Brain volume changes, especially increases in WMH, were associated with declines in each of the cognitive abilities. All statistically significant results were modest in size (absolute r‐values ranged from 0.114 to 0.334). These results build a comprehensive picture of macrostructural brain volume changes and declines in important cognitive faculties during the eighth decade of life. Hum Brain Mapp 36:4910–4925, 2015. © 2015 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc  相似文献   
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Nigral tissue accumulated 14C-glycine by an energy-, temperature- and sodium-dependent mechanism; the transport process was inhibited by small neutral amino acids and had an apparent Km of 143 microM and Vmax of 787 nmol/g/min. Re-release of accumulated 14C-glycine was initially extremely rapid (40% in first 5 min) and subsequently accelerated by +40 mM K+ in a Ca2+-dependent manner. Intranigral kainate (0.25 microgram) lowered the levels of striatal DA (63%) and nigral GABA (25%) ipsilaterally, but not nigral glycine. Injections of glycine or strychnine (10--100 micrograms) into one SN induced slow ipsiversive or contraversive turning respectively. The evidence for glycine as a neurotransmitter in SN is discussed.  相似文献   
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Background The direct-weighted Schedule for the Evaluation of Individual Quality of Life, Direct Weighting (SEIQoL-DW) is an individualised measure of QoL that has been little used in very elderly people. Methods We administered SEIQoL-DW during Wave 5 of the Aberdeen Birth Cohort 1921 Study (ABC1921) and sought statistical correlations with other variables in the data set. ABC1921 participants had been IQ-tested in 1932 at age 11. Since 1997, data about cognition, mental/physical function, personality, health, and socioeconomic status have been gathered in five waves of investigations. Results Ninety-six out of 98 individuals, mean age 82.2, completed the SEIQoL-DW. Health, family, relationships, finances and social pastimes were the commonest cues nominated, but age/gender differences existed. The mean SEIQoL-DW score (74.0) was significantly lower than in an approximately 60% sample from Wave 3, the fall being greater in men. Variables statistically associated with Wave 5 SEIQoL-DW usually reflected current rather than past status [including Short-Form 36 Health Survey (SF-36) components and depression], although there were weaker correlations with years of education, housing in childhood, conscientiousness, and IQ in 1998. Conclusions SEIQoL-DW proved feasible and acceptable in community-dwelling octogenarians. Recent (i.e. statelike) rather than early or long-standing (i.e. traitlike) influences appeared to have the greater effect on QoL.  相似文献   
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Working with the Ohio Department of Alcohol and Drug Addiction Services (ODADAS) and researchers at the University of Akron, Wright State University's Center for Interventions, Treatment, and Addictions Research developed the Ohio Substance Abuse Monitoring (OSAM) Network to provide a statewide summary of substance abuse trends. Ten key informants across the state collect qualitative and statistical data on substance abuse trends in their regions and prepare biannual reports. The OSAM network has a rapid response capability through which key informants can investigate special issues related to substance abuse identified by ODADAS and provide policymakers with timely, statewide reports. Within 12 months after operations began, the key informants produced reports on drug abuse trends and rapid response issues for the state. These reports prepared policymakers to respond more effectively to prevention and substance abuse treatment needs.  相似文献   
109.
The auditory evoked brain stem potential was recorded in 14 normal full-term infants and nine normal-hearing adults. Silver-silver chloride electrodes were placed at nasion, forehead, vertex, each mastoid over the bony prominence, and the seventh cervical vertebra (noncephalic reference) in order to study the scalp distribution of the auditory brain stem response. Large differences in the scalp distribution between the newborn and adult populations were observed. At the ipsilateral mastoid, an x wave occurring at approximately 2 ms and a y wave occurring at approximately 3.3 ms were identified in the adult; this contrasts to a y wave at approximately 3.7 ms in the neonate. It appears that there are either separate generators for some of the components in the adult versus the neonate, and/or as the nervous system matures, myelinization occurs with a concomitant change in the scalp distribution of the auditory brain stem potentials.  相似文献   
110.
The possibility that platelet aggregation is altered during pregnancy is controversial. We tested for alterations of alpha-adrenergic receptor-induced platelet function during pregnancy compared to that in the early phase of the menstrual cycle. We found no change in alpha-adrenergic receptor concentration or in affinity of the receptor for epinephrine. The potency and sensitivity of epinephrine to inhibit adenylate cyclase, a response mediated by alpha 2-adrenergic receptors, was not different in platelets from the two groups of subjects. The ability of epinephrine to potentiate aggregation by adenosine diphosphate was significantly increased during pregnancy; however, this was an artifact introduced by lower hematocrits during pregnancy that resulted in an increased citrate concentration in the preparations of platelet-rich plasma from these women. The difference was eliminated by normalization of citrate concentration. Thus effects of alpha-adrenergic receptors on platelet function are not different during pregnancy. It is mandatory to recognize artifactual effects of differing hematocrits on platelet aggregation studied in vitro.  相似文献   
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