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71.
Stephen Hanney Shyama Kuruvilla Bryony Soper Nicholas Mays 《Health research policy and systems / BioMed Central》2010,8(1):11
Health research systems consist of diverse groups who have some role in health research, but the boundaries around such a
system are not clear-cut. To explore what various stakeholders need we reviewed the literature including that on the history
of English health R&D reforms, and we also applied some relevant conceptual frameworks. 相似文献
72.
高三尖杉酯碱在大鼠及兔肝微粒体的代谢研究 总被引:1,自引:0,他引:1
采用动物肝微粒体体外代谢法对高三尖杉酯碱进行了代谢转化的研究。应用梯度洗脱—反相HPLC结合二极管陈列检测器对体外代谢体系进行了分析。判定在体外代谢体系中,高三尖杉酯碱主要产生一个代谢产物。用HPLC法制备出一定量代谢物纯品,经光谱分析及与化学制备的对照品相比较,推定其代谢物结构为:2′-羟基-2′(α-乙酸)-6′-甲基-6′-羟基-庚酰三尖杉碱。 相似文献
73.
74.
We review the current therapy for cutaneous malignant melanoma. Early surgical resection offers the best likelihood of cure. The initial staging of melanoma patients determines subsequent therapeutic decisions and follow-up care. The prognosis and appropriate therapy for each stage of melanoma are discussed. We review the controversy over lymph node dissection, and recent recommendations for the use of lymphoscintigraphy. Interferon-alpha continues to be the only Food and Drug Administration-approved adjuvant therapy for high-risk patients. In addition, the follow-up care of melanoma patients will be discussed. 相似文献
75.
76.
Gregor Coster Nicholas Mays Claudia Scott Jacqueline Cumming 《The International journal of health planning and management》2009,24(4):276-289
Objectives District Health Boards (DHBs) in New Zealand are mandated to assess and prioritise the health needs of their resident populations. This paper evaluates the impact of those health needs assessments (HNAs) and prioritisation practices on health service planning and purchasing in the first 3 years of the DHBs (2001–2003). Methods DHB HNAs, 5‐yearly strategic plans, and annual plans were evaluated using document analysis to determine the impact of needs assessments on prioritisation and planning by boards. Key informant interviews with DHB senior managers were used to identify differences between boards. Results HNAs had relatively little influence on the direction of planning and purchasing. HNAs conducted in DHBs that focussed on planning at the service level and in relation to population subgroups using a ‘mixed‐scanning’ approach and ‘service planning groups’ had a greater impact on planning and purchasing than more comprehensive approaches. DHBs found prioritisation difficult due to the level of control exercised by central government over their actions. Conclusions HNAs in New Zealand need to be less ambitious, more focussed and more closely institutionally linked to prioritisation, service planning and purchasing processes if they are to have an impact on the allocation of resources. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
77.
78.
Long- and short-term monocular deprivation in the rhesus monkey: effects on visual fields and optokinetic nystagmus 总被引:1,自引:0,他引:1
Monkeys with 1 eyelid sutured within 2 weeks of birth for 7 or 14 d (short-term monocular deprivation, n = 5) or for 18-26 months (long-term monocular deprivation, n = 5) were tested for visual and oculomotor function at approximately 2 years of age. Long-term monocularly deprived animals were behaviorally blind when visual inputs were restricted to the deprived eye. There was no sparing of the monocular segment of the visual field, and optokinetic nystagmus could not be elicited even with vertical stripes up to 15 degrees in width. These behavioral deficits could not be accounted for by optical or retinal abnormalities. In contrast, short-term monocularly deprived animals displayed normal visual fields and optokinetic nystagmus was driven by both eyes. Slow-phase gain was reduced and directional asymmetries were observed when optokinetic stimulation was restricted to the deprived eye. 相似文献
79.
R J McAnulty S R Moores R J Talbot J E Bishop P K Mays G J Laurent 《International journal of radiation biology》1991,59(1):229-238
Mice were exposed by nose-only inhalation to 239PuO2, which resulted in an IAD of 1110 +/- 29 Bq. At various times after exposure, rates of collagen metabolism were measured using validated in vivo methods based on the administration of radiolabelled proline, together with a large flooding dose of unlabelled proline and measurement of its incorporation into lung collagen as hydroxyproline. Dramatic increases in both synthesis and degradation rates of collagen were observed. At 54 days after exposure the fractional synthesis rates in experimental mice were almost five times those in controls (control: 3.2 +/- 0.6%/day, 239PuO2-exposed: 14.5 +/- 0.4%/day) and by 300 days synthesis rates, although declining, were still more than double the control values. A similar pattern of change was observed for collagen degradation. The combination of changes in synthesis and degradation rates led to a 60% increase in lung collagen content by 300 days (control: 3.05 +/- 0.24 mg/lung, 239PuO2-exposed: 4.88 +/- 0.42 mg/lung). The data suggest that extensive remodelling of the lung connective tissue matrix occurs during development of fibrosis and that, over long periods of time, small imbalances between synthesis and degradation may result in quite large increases in protein content. 相似文献
80.
1. Rhesus monkeys were trained to look to brief visual targets presented in an otherwise darkened room. On some trials, after the visual target was extinguished but before a saccade to it could be initiated, the eyes were driven to another orbital position by microstimulation of the paramedian pontine reticular formation. If, as current models of the saccadic system suggest, a copy of the motor command is used as a feedback signal of eye position, failure to compensate for stimulation-induced movements would indicate that stimulation occurred at a site beyond the point from which the eye position signal was derived. 2. Animals compensated for perturbations of eye position induced by stimulation of most pontine sites by making saccades that directed gaze to the position of the visual target. With stimulation at other pontine sites, compensatory saccades did not occur. 3. Pontine stimulation sometimes triggered, prematurely, impending visually directed saccades. The direction and amplitude of the premature movement depended upon the location of the briefly presented visual target. The amplitude of the premature movement was also a function of the interval between the stimulation train and the impending saccade. These data suggest that input signals for the horizontal and vertical pulse/step generators develop gradually during the presaccadic interval. Saccade trigger signals need to be delayed until the formation of these signals is completed. 4. The implications of these findings for models of the saccadic system are discussed. Robinson's local feedback model of the saccadic system can explain compensation for pontine stimulation-induced changes in eye position but cannot easily account for the failure to compensate for perturbations in eye position produced by stimulation at other sites. Modified versions of Robinson's model, which assume that the input signal to the pulse/step generator is the desired displacement of the eye, can account for both compensation and the failure to compensate since two separate neural integrators are employed. However, these models ignore kinematic arguments that commands to the extraocular muscles must specify the absolute position of the eye in the orbit rather than a relative movement from a previous position. 相似文献