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1.
Ling Zhang Xue-Jun Shang Hong-Fei Li Yu-Qin Shi Wei Li Maria E Teves Zhi-Qiong Wang Gao-Feng Jiang Shi-Zhen Song Zhi-Bing Zhang 《Asian journal of andrology》2015,17(1):86-93
Mammalian spermatogenesis is a well-organized process of cell development and differentiation. Meiosis expressed gene 1 (MEIG1) plays an essential role in the regulation of spermiogenesis. To explore potential mechanisms of MEIG1''s action, a yeast two-hybrid screen was conducted, and several potential binding partners were identified; one of them was membrane occupation and recognition nexus repeat containing 3 (MORN3). MORN3 mRNA is only abundant in mouse testis. In the testis, Morn3 mRNA is highly expressed in the spermiogenesis stage. Specific anti-MORN3 polyclonal antibody was generated against N-terminus of the full-length MORN3 protein, and MORN3 expression and localization was examined in vitro and in vivo. In transfected Chinese hamster ovary cells, the antibody specifically crossed-reacted the full-length MORN3 protein, and immunofluorescence staining revealed that MORN3 was localized throughout the cytoplasm. Among multiple mouse tissues, about 25 kDa protein, was identified only in the testis. The protein was highly expressed after day 20 of birth. Immunofluorescence staining on mixed testicular cells isolated from adult wild-type mice demonstrated that MORN3 was expressed in the acrosome in germ cells throughout spermiogenesis. The protein was also present in the manchette of elongating spermatids. The total MORN3 expression and acrosome localization were not changed in the Meig 1-deficient mice. However, its expression in manchette was dramatically reduced in the mutant mice. Our studies suggest that MORN3 is another regulator for spermatogenesis, probably together with MEIG1. 相似文献
2.
AbstractPurpose: In the context of assistive technology, mobility takes the meaning of “moving safely, gracefully, and comfortably”.The aim of this article is to provide a system which will be a convenient means of navigation for the Visually Impaired people, in the public transport system.Method: A blind regular commuter who travels by public transport facility finds difficulty in identifying the vehicle that is nearing the stop. Hence, a real-time system that dynamically identifies the nearing vehicle and informs the commuters is necessary. This paper proposes such a system namely the “Vehicle Board Recognition System” (VBRS). Computer Vision techniques such as segmentation, object recognition, text detection and optical character recognition are utilized to build the system, which will detect, analyze, derive and communicate the information to the passengers.Results: Thanks to the rapid development in technology, there are several navigation systems both hand held and wearable, available to help visually impaired (VI) people move comfortably both indoor and outdoor. Many blind people are not comfortable in using these devices or they are not affordable for them. Thus the proposed system gives them the comfort of navigation.Conclusion: This system can be installed in the bus stop to assist the Visually Impaired, from externally rather than their hand held or wearable assistive devices.
- Implications for rehabilitation
This proposed system will help the visually impaired to
ensure secure navigation
be independent of the others
develop self confidence.
overcome the training, affordability of wearable/ handheld devices.
3.
Olgierd Pucilowski W. Danysz D.H. Overstreet A.H. Rezvani B. Eichelman D.S. Janowsky 《Brain research bulletin》1991,26(4):621-625
The Flinders Sensitive Line (FSL) of rats has been selectively bred to have increased sensitivity to cholinergic agonists. However, these rats exhibit altered responsiveness to a number of noncholinergic agents, such as apomorphine, buspirone and ethanol. This study compared the FSL and control Flinders Resistant Line (FRL) rats in terms of their hyperthermic response to the phencyclidine (PCP) receptor agonist, MK-801 (0.2 mg/kg SC) and their MK-801 binding characteristics. We have found that FSL rats react with a delayed hyperthermia, having a significantly lower hyperthermia for the first 120 min of observation. Thereafter the response does not differ in FSL and FRL rats. Both groups had similar affinities and numbers of [3H]MK-801 binding sites in the hippocampus/cerebral cortex. Pretreatment with scopolamine (1 mg/kg SC) failed to affect MK-801-induced hyperthermia in either line of rats. These findings suggest that selective breeding of FSL rats attenuated the secondary mechanisms involved in the PCP receptor-mediated hyperthermic response. However, by itself cholinergic supersensitivity does not appear to be a major factor in the blunted responsiveness of FSL rats to MK-801. 相似文献
4.
Physiologic assessment of diseases of the motor unit from the anterior horn cells to the muscles relies on a combination of needle electromyography (EMG) and nerve conduction studies (NCS). Both require a unique combination of knowledge of peripheral nervous system anatomy, physiology, pathophysiology, diseases, techniques, and electricity is necessary. Successful, high‐quality, reproducible EMG depends on the skills of a clinician in patient interaction during the physical insertion and movement of the needle while recording the electrical signals. These must be combined with the skill of analyzing electric signals recorded from muscle by auditory pattern recognition and semiquantitation. 10 , 52 This monograph reviews the techniques of needle EMG and waveform analysis and describes the types of EMG waveforms recorded during needle EMG. © 2009 Wiley Periodicals, Inc. Muscle Nerve 39: 244–270, 2009 相似文献
5.
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons. 相似文献
6.
甲襞微循环观测辅助诊断的初步研究胡金麟*田牛*刘凤英*宋欣*李向红*规范化的甲襞、球结膜、舌、口唇、牙龈、耳廓、皮肤、子宫颈、阴茎头微循环观测方法标志着我国临床微循环的研究与应用已进入了一个新的阶段[1,2]。临床微循环观测结果的数学公式表达,促进了... 相似文献
7.
8.
Visual recognition impairment follows ventromedial but not dorsolateral prefrontal lesions in monkeys 总被引:15,自引:0,他引:15
Visual recognition in monkeys appears to involve the participation of two limbothalamic pathways, one including the amygdala and the magnocellular portion of the medial dorsal nucleus (MDmc) and the other, the hippocampus and the anterior nuclei of the thalamus (Ant N). Both MDmc and Ant N project, in turn, to the prefrontal cortex, mainly to its ventral and medial portions. To test whether the prefrontal projection targets of the two limbothalamic pathways also participate in memory functions, performance on a variety of learning and memory tasks was assessed in monkeys with lesions of the ventromedial prefrontal cortex (Group VM). Normal monkeys and monkeys with lesions of dorsolateral prefrontal cortex (Group DL) served as controls. Group VM was severely impaired on a test of object recognition, whereas Group DL did not differ appreciably from normal animals. Conversely, the animals in Group VM were able to learn a spatial delayed response task, whereas 2 of the 3 animals in Group DL could not. Neither group was impaired in the acquisition of visual discrimination habits, even though the successive trials on a given discrimination were separated by 24-h intervals. The patterns of deficit suggest that ventromedial prefrontal cortex constitutes another station in the limbothalamic system underlying cognitive memory processes, whereas the dorsolateral prefrontal cortex lies outside this system. The results support the view that the classical delayed-response deficit observed after dorsolateral prefrontal lesions represents a perceptuo-mnemonic impairment in spatial functions selectively rather than a memory loss of a more general nature. 相似文献
9.
10.
男性不育症患者中YRRM2基因缺陷的研究 总被引:2,自引:1,他引:1
YRRM基因是控制精子生成与成熟的一个重要因素,一旦该基因缺陷,将会造成无精或少精。本研究对340例无精与少精患者的外周血标本进行了PCR基因扩增筛查,结果发现7例为该基因缺陷,占2%。证明YRRM2的缺陷也是造成中国人群男性不育的一个原因,从而可作为指导医生采用适当治疗方法的一个可靠指标。在实验过程中,采用直接加热白细胞提取基因组DNA,并以此作为模板对YRRM2基因进行扩增,既节省时间和经费,又保持良好的扩增效果,使之可用于临床医院作为常规检查。 相似文献