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101.
We analysed the effect of exposure to tobacco smoke during pregnancy on fetal growth parameters in 129 term newborns. Children were classified into four depending on exposure on the basis of a questionnaire completed by the mother. The results confirmed that tobacco smoking reduced weight, length, cranial and thoracic perimeters at birth when exposure was due to either active or passive smoking. Weight deficits of infants whose mothers smoked heavily (458 g) were higher than those whose mothers were exposed to passive smoking (192 g). We conclude that passive smoking is a very important variable and should be taken into account in any study of neonatal growth parameters. 相似文献
102.
103.
Neuronal loss is greater in the locus coeruleus than nucleus basalis and substantia nigra in Alzheimer and Parkinson diseases 总被引:17,自引:0,他引:17
CONTEXT: Alzheimer disease (AD) and Parkinson disease (PD) are associated with neuronal degeneration in major subcortical nuclei, but few studies have examined the neuronal degeneration in these nuclei concurrently. OBJECTIVE: To identify clinical and pathological correlates of neuronal loss in the nucleus basalis (NB), locus coeruleus (LC), and substantia nigra pars compacta (SN) in AD and PD. DESIGN: The study sample comprised 86 cases with pathologically confirmed AD, 19 cases with PD, and 13 healthy elderly control subjects. The number of nucleolated neurons was counted in representative sections of the NB, LC, and SN. Effect sizes (ES) were computed to determine the standardized difference in cell counts relative to healthy controls. RESULTS: Cases of AD showed the greatest neuronal loss in the LC (ES = 3.16) followed by the NB (ES = 1.10), but variable loss in the SN (ES = 0.16). Cases of PD also showed the greatest neuronal loss in the LC (ES = 6.47), followed by the SN (ES = 2.58) and the NB (ES = 0.85). Significant correlations were found between the number of neurons in the NB and LC in PD (r = 0.54, P<.05), as well as AD (r = 0.24, P<.05). The duration of illness correlated with greater neuronal loss in the LC and NB in AD, and greater neuronal loss in the SN in PD. CONCLUSIONS: For both AD and PD the greatest neuronal loss was found in the LC. In AD, neuronal loss was most severe and best correlated with the duration of illness in the LC, rather than in NB as traditionally expected. Correlations between neuronal loss in the LC and NB (but not SN) in both PD and AD suggest that the former 2 nuclei may share common pathogenetic susceptibilities. Given the prominent loss of neurons in the LC, detection and treatment of noradrenergic deficiencies warrant attention in both AD and PD. 相似文献
104.
Monge-Argiles J Maloteaux J Van Den Bergh P Sindic C 《Neurología (Barcelona, Spain)》2002,17(2):110-112
We report a patient with a peripheral neuropathy as the first symptom of sarcoidosis. The systemic illness was proved by the presence of typic granulomes in the bone marrow. The fact that sarcoidosis is the cause for the neuropathy is supported by the temporary relation and by the good response of all clinical picture to the corticosteroid therapy.Sarcoid neuropathy can rarely be the presenting feature of sarcoidosis. 相似文献
105.
Hans JM van Grinsven Mary H Ward Nigel Benjamin Theo M de Kok 《Environmental health : a global access science source》2006,5(1):26-6
Several authors have suggested that it is safe to raise the health standard for nitrate in drinking water, and save money
on measures associated with nitrate pollution of drinking water resources. The major argument has been that the epidemiologic
evidence for acute and chronic health effects related to drinking water nitrate at concentrations near the health standard
is inconclusive. With respect to the chronic effects, the argument was motivated by the absence of evidence for adverse health
effects related to ingestion of nitrate from dietary sources. An interdisciplinary discussion of these arguments led to three
important observations. First, there have been only a few well-designed epidemiologic studies that evaluated ingestion of
nitrate in drinking water and risk of specific cancers or adverse reproductive outcomes among potentially susceptible subgroups
likely to have elevated endogenous nitrosation. Positive associations have been observed for some but not all health outcomes
evaluated. Second, the epidemiologic studies of cancer do not support an association between ingestion of dietary nitrate
(vegetables) and an increased risk of cancer, because intake of dietary nitrate is associated with intake of antioxidants
and other beneficial phytochemicals. Third, 2–3 % of the population in Western Europe and the US could be exposed to nitrate
levels in drinking water exceeding the WHO standard of 50 mg/l nitrate, particularly those living in rural areas. The health
losses due to this exposure cannot be estimated. Therefore, we conclude that it is not possible to weigh the costs and benefits
from changing the nitrate standard for drinking water and groundwater resources by considering the potential consequences
for human health and by considering the potential savings due to reduced costs for nitrate removal and prevention of nitrate
pollution. 相似文献
106.
107.
108.
Marijke JM Chin A Paw Amika S Singh Johannes Brug Willem van Mechelen 《The international journal of behavioral nutrition and physical activity》2008,5(1):41
Objectives
This paper aims to identify the mediating mechanisms of a school-based obesity prevention program (DOiT). 相似文献109.
Background
The Licensing Act 2003 (The Act) was implemented on the 24th November 2005 across England and Wales. The Act allowed more flexible and longer opening hours for licensed premises. We investigated the effect of The Act on alcohol related attendances to an inner city emergency department in Birmingham, UK. 相似文献110.
Although exposure of LLC-PK1 epithelial cell sheets to phorbol esters (TPA)
causes a near immediate and total decrease of transepithelial electrical
resistance (TER), continuation of exposure for 3 to 4 days results in a
tachyphylactic response as TER begins to return to control levels. Recovery
of TER is maximal by 5 to 6 days, but reaches only 70 to 80% of control
level. A reciprocal change in the transepithelial flux of D-mannitol
indicates that the TER decrease is indicative of an increase in tight
junction permeability. Exposure of cell sheets to TPA for several days also
results in the appearance of multilayered polyp- like foci (PLFs) across
the otherwise one cell layer thick cell sheets. The pattern of penetration
of the electron dense dye, ruthenium red, from the apical surface, across
the tight junction and into the lateral intercellular space indicates that
the tight junctions of the cell sheet become uniformly leaky after acute
exposure to TPA. However, when exposure is continued for several days, only
the junctions of cells in the PLFs manifest leakiness. The decrease in TER
following acute TPA exposure correlates with the translocation of protein
kinase C-alpha (PKC alpha) into a membrane-associated compartment. With
exposure of several days, only a trace of PKC alpha is visible by Western
immunoblot, and this is in the membrane-associated compartment.
Immunofluorescent microscopy indicates that the trace of PKC alpha seen in
the Western immunoblots is ascribable distinctly to cells of the PLFs.
Monolayer areas between PLFs show no discernible immunofluorescent signal.
The data therefore indicate that tight junction barrier function may be
restored in certain areas by the down regulation of PKC alpha from the
membrane-associated compartment. Failure to down regulate may result in the
paracellular leakiness and abnormal cell architecture of the PLFs. Possible
implications of this model for in vivo epithelial tumor promotion are
discussed.
相似文献