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91.
BACKGROUND AND PURPOSE: In the last years the presence of peripheral nervous system (PNS) lesions has been noted in patients with multiple sclerosis (MS). The frequency and degree of PNS damage reported by many authors differ among publications, so does the type of PNS lesions. The aim of our study was to perform an electrophysiological evaluation of the peripheral nervous system in patients with a definite diagnosis of multiple sclerosis and without any clinical signs of peripheral neuropathy. MATERIAL AND METHODS: 110 patients were included in the study, comprising 70 people with a definite diagnosis of multiple sclerosis and 40 people without any symptoms of organic nervous system lesion serving as a control group. During neurologic examination of MS patients the degree of disability measured by EDSS scale, the duration of the disease as well as number of relapses were assessed. A "disease progression factor" was calculated by dividing a number of relapses by disease duration in years. Patients with common etiologies for peripheral neuropathy such as diabetes, renal insufficiency, thyroid gland dysfunction, proliferative disorders etc. were excluded from the study. Orthodromic motor conduction and late responses (F wave) in median, ulnar, peroneal and tibial nerves as well as sensory conduction in median, ulnar (orthodromic) and sural (antidromic) nerves were evaluated. RESULTS: There was electrophysiological evidence of peripheral nervous system lesions in at least one nerve in 52 (74.2%) MS patients. In 30 patients (42.8%) more than one peripheral nerve was lesioned. There were more significant differences noted during the examination of sensory nerves. Sensory amplitudes in all of the sensory nerves examined were significantly lower than in control group. Furthermore we observed slow sensory conduction velocities and prolonged sensory latencies in ulnar and sural nerves. There were significant differences between the two groups of patients concerning motor conduction too: prolonged distal latency in tibial and sural nerves, prolonged F wave latency in median, peroneal and tibial nerves, low motor amplitude in ulnar and peroneal nerves, low motor conduction velocity in ulnar nerve -- all noted in MS patients. We found no correlation between conduction parameters and the patients' age, disease duration, number of relapses and disease progression degree. CONCLUSIONS: We found out that subclinical peripheral nervous system abnormalities are very frequent in MS patients. We noted both sensory and motor nerve lesions of a demyelinating-axonal character. Sensory abnormalities were more pronounced than motor ones. There was no correlation between the degree of PNS lesions and the patients' age and/or progression of multiple sclerosis. 相似文献
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Anna Ptak Patrycja Gut Magorzata Bachuta Agnieszka Rak Ewa . Gregoraszczuk 《Toxicology letters》2009,190(2):187-192
Our previously published data showed that 260 h of exposure to 3,4-diOH-PCB3 decreased proliferation in the MCF-7 cell line. In the present study, we sought to determine whether this is due to action on the SHBG/cAMP/PKA system, activation of which can inhibit cell proliferation, or to direct inhibition of ERK1/2 phosphorylation. MCF-7 human breast cancer cells were treated for 72 h with 4-monochlorobiphenyl (PCB3), 4′-hydroxy-4-monochlorobiphenyl (4-OH-PCB3) or 3′4′-dihydroxy-4-monochlorobiphenyl (3,4-diOH-PCB3) (300 nM). After the completion of the treatment, cell proliferation was measured with a BrdU incorporation assay. SHBG, cAMP, PKA and ERK1/2 levels in the cells were determined via ELISA.PCB3 and 4-OH-PCB3 had no effect on extra- or intracellular SHBG levels, while a stimulation of SHBG intra- but not extracellular levels was noted in cells exposed to 3,4-diOH-PCB3. Both, pre- and co-incubation with SHBG decreased the proliferation of 3,4-diOH-PCB3-treated cells. Neither PCB3 nor its metabolite had an effect on the cAMP/PKA pathway. A decrease of both ERK1/2 forms was noted under the influence of 3,4-diOH-PCB3. In conclusion, the data presented clearly showed that the antiproliferative action of 3,4-diOH-PCB3 is not mediated by activation of the SHBG/AMP/PKA pathway, but many other plasma membrane receptors seem to be involved in the non-genomic action of 3,4-diOH-PCB3, and instead is due to direct inhibition of the ERK1/2 system. 相似文献
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Ewa Taracha Paweł Mierzejewski Małgorzata Lehner Stanisław J. Chrapusta Maria Kała Wojciech Lechowicz Adam Hamed Anna Skórzewska Wojciech Kostowski Adam Płaźnik 《Pharmacological reports : PR》2009,61(3):424-435
The utility of methadone and morphine for analgesia and of methadone for substitution therapy for heroin addiction is a consequence of these drugs acting as opioid receptor agonists.We compared the cataleptogenic and antinociceptive effects of single subcutaneous doses of methadone hydrochloride (1–4 mg/kg) and morphine sulfate (2.5–10 mg/kg) using catalepsy and hot-plate tests, and examined the effects of the highest doses of the drugs on Fos protein expression in selected brain regions in male Sprague-Dawley rats. Methadone had greater cataleptogenic and analgesic potency than morphine. Fos immunohistochemistry revealed substantial effects on the Fos response of both the stress induced by the experimental procedures and of the drug exposure itself. There were three response patterns identified: 1) drug exposure, but not stress, significantly elevated Fos-positive cell counts in the caudate-putamen; 2) stress alone and stress combined with drug exposure similarly elevated Fos-positive cell counts in the nucleus accumbens and cingulate cortex; and 3) methadone and morphine (to a lesser extent) counteracted the stimulatory effect of nonpharmacological stressors on Fos protein expression in the somatosensory cortex barrel field, and Fos-positive cell counts in this region correlated negatively with both the duration of catalepsy and the latency time in the hot-plate test. The overlap between brain regions reacting to nonpharmacological stressors and those responding to exogenous opioids suggests that stress contributes to opioid-induced neuronal activation. 相似文献
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Dorota Piotrowska-Kownacka Lukasz Kownacki Marek Kuch Ewa Walczak Agnieszka Kosieradzka Anna Fidzianska Leszek Krolicki 《Journal of cardiovascular magnetic resonance》2009,11(1):12
Danon disease is a rare X-linked dominant lysosomal glycogen storage disease that can lead to severe ventricular hypertrophy and heart failure. We report a case of Danon disease with cardiac involvement evaluated with cardiovascular magnetic resonance, including late gadolinium enhancement and perfusion studies. 相似文献
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Märtha Sund-Levander RNT PhD Ewa Grodzinsky BLS 《International journal of nursing practice》2009,15(4):241-249
The definition of normal body temperature as 37°C still is considered the norm worldwide, but in practice there is a widespread confusion of the evaluation of body temperature, especially in elderly individuals. In this paper, we discuss the relevance of normal body temperature as 37°C and consequences in clinical practice. Our conclusion is that body temperature should be evaluated in relation to the individual variability and that the best approach is to use the same site, and an unadjusted mode without adjustments to other sites. If the baseline value is not known, it is important to notice that frail elderly individuals are at risk of a low body temperature. In addition, what should be regarded as fever is closely related to what is considered as normal body temperature. That is, as normal body temperature shows individual variations, it is reasonable that the same should hold true for the febrile range. 相似文献