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101.
In various series reported in the literature on the operative management of severe head injuries with compound depressed skull fractures and penetrating wounds of the brain, the rates of infection differ from 1 to 17%. In this paper the operative experience with 22 cases of penetrating head injuries is discussed. In conventional operative therapy, depressed skull fracture and lacerated dura were covered by "Sulmycin Implant" containing Gentamycin as a helpful bacteriological barrier. 18 patients survived, 7 patients had severe neurological defects, 5 patients had mild neurological deficits and 6 patients recovered completely. There were no signs of suppurative complications in superficial wounds or in the brain. 4 patients died due to their severe brain damage with multiple contusional lesions. Postoperative complications were as follows: one patient suffered extradural and one patient subdural rebleeding. Another patient with a frontal base skull fracture suffered a pneumatocele because the fracture was not correctly covered. The revision was done successfully using the "Sulmycin Implant". Presently, however, the intradural use of "Sulmycin Implant" is not recommended without further testing for the level of gentamycin in the cerebrospinal fluid which is released by the "Sulmycin Implant". 相似文献
102.
103.
L-DOPA-induced dyskinesias are one of the main problems encountered in treating patients with Parkinson's disease (PD). They are induced by the antiparkinsonian medications and primarily related to the degree of dopaminergic depletion, as shown by the fact that they tend to appear several years after the onset of the disease. Do the initial therapeutic decisions taken in treating a PD patient influence the point at which dyskinesias first occur? This question is raised in view of the apparent priming phenomenon that occurs in first exposure to L-DOPA. L-DOPA administrated to an MPTP intoxicated monkey rapidly corrects the animals' motor symptoms but generate dyskinesias. In contrast, the administration of dopaminergic agonists with a long half-life has a similar therapeutic effect but without inducing dyskinesias. However, a parkinsonian monkey that had received L-DOPA and developed dyskinesias, which were subsequently abolished when the treatment was withdrawn for several months, proceeded to develop dyskinesias when treatment with dopaminergic agonists with long half-life was introduced. The monkeys' previous exposure to L-DOPA (i.e. priming) thus increased its susceptibility to develop dyskinesias after exposure to drugs which would not otherwise have had this effect. Pulsatile activation of type D2 dopamine receptors is reported to be the principal factor in the triggering of dyskinesias and may well be involved in the priming phenomenon. While the pathophysiological basis of priming is not yet known, the phenomenon would not appear to be related to a hyperexpression of dopamine receptors (types D1 and D2) in the sensorimotor striatum. The results of recent experiments have given rise to several different hypothesis for the mechanisms involved in priming: the role of internalization of dopamine receptors after administration of dopaminergic drugs; change in the distribution of D3 dopamine receptor; changes in the expression of peptides (substance P, enkephalin) in efferent neurons of the striatum; and reorganization of connections at the level of the dopaminergic neurons and their target tissue. While many questions remain unanswered, it may well be that the initial therapeutic decisions taken when treating de novo patient are crucial in trying to delay the onset of dyskinesias. 相似文献
104.
Vila M Périer C Féger J Yelnik J Faucheux B Ruberg M Raisman-Vozari R Agid Y Hirsch EC 《The European journal of neuroscience》2000,12(1):337-344
Cellular expression of cytochrome oxidase subunit I (COI) mRNA has recently been used as a metabolic marker for neuronal activity to study the functional changes in the subthalamic nucleus (STN) in parkinsonism. The previous experimental studies have been performed when the pathological state was stabilized at a maximal level. In order to determine the evolution of changes in neuronal activity in the STN after nigrostriatal denervation, we analysed by in situ hybridization the cellular expression of COI mRNA in the subthalamic neurons at different times, from 6 h to 14 days, after unilateral intranigral microinjection of 6-hydroxydopamine (6-OHDA) in rats. In parallel, the time-dependent changes of the unit neuronal activity of subthalamic neurons have been recorded. Levels of COI mRNA increased by 41% in subthalamic neurons from 24 h after 6-OHDA intoxication, to 14 days (+26%). Similarly, electrical activity started to increase slightly 24 h after lesion (+20%) and remained significantly higher at 14 days after the lesion (+189%). Changes in neuronal mean discharge rate were associated with changes in the pattern of spiking activity, from a regular firing pattern to an irregular one with a high bursting activity. These results show that: (i) the hyperactivity of the STN represents a very early phenomenon in the physiopathology of parkinsonian syndromes; and (ii) that changes in COI mRNA expression slightly precede changes in electrical neuronal activity. 相似文献
105.
Judy F Flax Teresa Realpe-Bonilla Linda S Hirsch Linda M Brzustowicz Christopher W Bartlett Paula Tallal 《J. Speech Lang. Hear. Res.》2003,46(3):530-543
Two family aggregation studies report the occurrence and co-occurrence of oral language impairments (LIs) and reading impairments (RIs). Study 1 examined the occurrence (rate) of LI and RI in children with specific language impairment (SLI probands), a matched control group, and all nuclear family members. Study 2 included a larger sample of SLI probands, as well as their nuclear and extended family members. Probands and their family members who met specific criteria were classified as language and/or reading impaired based on current testing. In Study 1, the rates of LI and RI for nuclear family members (excluding probands) were significantly higher than those for control family members. In the SLI families, affected family members were more likely to have both LI and RI than either impairment alone. In Study 2, 68% of the SLI probands also met the diagnostic classification for RI. The language and RI rates for the other family members, excluding probands, were 25% and 23% respectively, with a high degree of co-occurrence of LI and RI (46%) in affected individuals. Significant sex ratio differences were found across generations in the families of SLI probands. There were more male than female offspring in these families, and more males than females were found to have both LIs and RIs. Results demonstrate that when LIs occur within families of SLI probands, these impairments generally co-occur with RIs. Our data are also consistent with prior findings that males show impairments more often than females. 相似文献
106.
Hirsch J Ruge MI Kim KH Correa DD Victor JD Relkin NR Labar DR Krol G Bilsky MH Souweidane MM DeAngelis LM Gutin PH 《Neurosurgery》2000,47(3):711-21; discussion 721-2
OBJECTIVE: To evaluate an integrated battery of preoperative functional magnetic resonance imaging (fMRI) tasks developed to identify cortical areas associated with tactile, motor, language, and visual functions. METHODS: Sensitivity of each task was determined by the probability that a targeted region was activated for both healthy volunteers (n = 63) and surgical patients with lesions in these critical areas (n = 125). Accuracy of each task was determined by the correspondence between the fMRI maps and intraoperative electrophysiological measurements, including somatosensory evoked potentials (n = 16), direct cortical stimulation (n = 9), and language mapping (n = 5), and by preoperative Wada tests (n = 13) and visual field examinations (n = 6). RESULTS: For healthy volunteers, the overall sensitivity was 100% for identification of the central sulcus, visual cortex, and putative Wernicke's area, and 93% for the putative Broca's area (dominant hemisphere). For patients with tumors affecting these regions of interest, task sensitivity was 97% for identification of the central sulcus, 100% for the visual cortex, 91% for the putative Wernicke's area, and 77% for the putative Broca's area. These sensitivities were enhanced by the use of multiple tasks to target related functions. Concordance of the fMRI maps and intraoperative electrophysiological measurements was observed whenever both techniques yielded maps and Wada and visual field examinations were consistent with fMRI results. CONCLUSION: This integrated fMRI task battery offers standardized and noninvasive preoperative maps of multiple critical functions to facilitate assessment of surgical risk, planning of surgical routes, and direction of conventional, intraoperative electrophysiological procedures. Thus, a greater range of structural and functional relationships is brought to bear in the service of optimal outcomes for neurosurgery. 相似文献
107.
Sheila A Prindiville Tim Byers Fred R Hirsch Wilbur A Franklin York E Miller Kieu O Vu Holly J Wolf Anna E Barón Kenneth R Shroyer Chan Zeng Tim C Kennedy Paul A Bunn 《Cancer epidemiology, biomarkers & prevention》2003,12(10):987-993
Individuals with cytological atypia in sputum may be at increased risk for lung cancer. We conducted a longitudinal analysis of the association between lung cancer incidence and cytological atypia in sputum samples collected prospectively from an ongoing cohort of adults at high risk for lung cancer. Cohort members had a smoking history of > or = 30 pack-years and chronic obstructive pulmonary disease documented by pulmonary airflow testing. Sputum samples collected at baseline and periodically thereafter were examined by standard cytological methods. From the cohort of 2,006 people, there were 83 incident lung cancers over 4,469 person-years of observation. At baseline, the association between personal and behavioral characteristics, and sputum cytological atypia was assessed by multiple logistic regression. The association between sputum cytological atypia and incident lung cancer was then assessed by hazard ratios using proportional hazards regression analysis, adjusting for potential confounding factors. Cytological atypia graded as moderate or worse was associated with continuing cigarette smoking (adjusted odds ratio, 2.5; 95% confidence interval, 1.5-4.1), and with lower levels of intake of fruits and vegetables (P for trend = 0.04). Atypia was not associated with several other factors, including the degree of airflow obstruction, the use of vitamin supplements, nonsteroidal anti-inflammatory drugs, or metered-dose steroid inhalers. Incident lung cancer was increased among those with moderate or worse cytological atypia (adjusted hazards ratio, 2.8; 95% confidence interval, 1.4-5.5). This association was not confounded by other risk factors. We conclude that in this high-risk cohort, cytological atypia is associated with continuing smoking and low intake of fruits and vegetables, but that independent of these and other factors, the risk of incident lung cancer is increased among those with moderate or worse grades of cytological atypia in their sputum. 相似文献
108.
109.
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions. 相似文献
110.