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61.
62.
End-stage periventricular leukomalacia: MR evaluation 总被引:3,自引:0,他引:3
A prospective study was performed to assess the capabilities of magnetic resonance (MR) imaging in evaluation of end-stage periventricular leukomalacia (PVL) in six children, aged 31-54 months, in whom PVL had been documented by neurologic ultrasonography during the neonatal period. Eight children of similar age (four premature infants and four full-term infants) with normal neurologic development served as controls. A characteristic triad of PVL abnormalities was seen on MR images: (a) abnormally increased periventricular white-matter signal intensity on the first and second echo images of a T2-weighted sequence (repetition time = 2,000-2,400 msec, echo times = 20 or 30 and 80 msec), most commonly observed in the trigone regions of the lateral ventricles bilaterally; (b) marked loss of periventricular white matter in these regions of abnormal signal intensity, predominantly in the periatrial regions; and (c) compensatory focal ventricular enlargement adjacent to regions of abnormal signal intensity. In patients with the classic periatrial distribution of PVL lesions, general correlation between the degree of neurologic impairment and the severity of MR abnormalities was demonstrated. MR imaging was useful in detecting subtle forms of PVL in cases in which neurologic damage was subclinical. 相似文献
63.
Background
Monoclonal gammopathies occurs in patients with malignant diseases of plasma cells and lymphocytes and in few benign conditions. The objective of this study was to assess the precision, accuracy and confirmation of monoclonal gammopathies on serum protein electrophoresis (SPE) and the clinical relevance of detection and characterization of M component.Methods
All samples received for serum electrophoresis in the last 3 years were analysed for data on M band positivity and correlating it with clinical profile of the patients. Immunofixation (IFE), Immunoelectrophoresis (IEP) and IgG, IgM estimation were carried out in few cases. The follow up of cases was done by serial monitoring of SPE and β2 microglobulin levels.Results
1155 samples were received during the 3 years period. 282 (24.4%) samples were positive for M component on SPE. Of these, 239 (84.8%) patients had M spike in λ region and 43 patients had M spike in β region. The mean load of the M protein band in the λ region was 37.8% and in β region was 35.8%. IgG with κ chain was seen in 40%, IgG with λ chain was seen in 50%, 5% patients each had IgM with κ and IgA with λ light chain. 246 samples (96.5%) had high levels of β2 microglobulin. Of the 116 cases of multiple myeloma, IgG levels was more commonly raised (5%) as compared to IgA (6.9%) and IgM (5.2%).Conclusion
It is recommended that SPE should be performed in patients having unexplained weakness, anaemia, back pain, osteoporosis, osteolytic lesions, fractures, renal insufficiency or recurrent infections.Key Words: Serum protein, Electrophoresis, M band, Multiple myeloma 相似文献64.
65.
66.
Dorsal hippocampus is one of the brain regions which plays an important role in anxiety. In the present study we investigated
the effects of Intra-dorsal hippocampus (CA1) microinjection of NMDA-glutamatergic receptor agonist, NMDA and its antagonist,
MK-801 on anxiety-related behavior in rats. Elevated plus-maze (EPM) which is one of the common methods employed for testing
of anxiety was used in this study. Rats were anaesthetized with a mixture of ketamine and xylazine and special cannulas were
inserted stereotaxically into the CA1 region of the dorsal hippocampus. After a one-week recovery, the effects of intra-CA1
administration of NMDA receptor agents were studied. Bilateral Intra-dorsal hippocampus microinjection of different doses
of NMDA (0.25, 0.5, 0.75 and 1 μg/rat) increased the percentage of open arm time (%OAT) and open arm entries (%OAE), indicating
an anxiolytic-like behavior. On the other hand, administration of MK-801 (60, 125, 250 and 500 ng/rat) decreased %OAT and
%OAE significantly. Pre-treatment administration of MK-801(60, 125, 250 and 500 ng/rat) reversed the anxiolytic effect of
NMDA (0.5 μg/rat) microinjection into the dorsal hippocampus in a dose-dependent manner. From the findings of the present
study, it can be concluded that the NMDA-glutamatergic system in the dorsal hippocampus is involved in anxiety-related behaviors. 相似文献
67.
68.
DK Ng KW Chau C Black TMM Thomas KL Mak & M Boxer 《Journal of paediatrics and child health》1999,35(3):321-323
A case of neonatal Marfan syndrome is presented. The patient was noted to have cardiomegaly and tricuspid regurgitation on antenatal ultrasound scan. She was born with long, slender fingers and toes, an aged appearance and non-paralytic hypotonia. Echocardiogram revealed a dilated right atrium, right ventricle, dysplastic tricuspid valve and severe tricuspid regurgitation. She subsequently died of severe heart failure. Post-mortem examination showed the pathological features of lobar emphysema and cystic medial necrosis of the aorta. These features supported the diagnosis of neonatal Marfan syndrome. Nucleotide sequencing showed substitution of G by A at codon 1032 in exon 25 located in the long arm of chromosome 15. This resulted in the substitution of a cysteine by a tyrosine. A de novo mutation is suggested by the absence of affected family members. 相似文献
69.
70.
Phencyclidine (1-(1-phenylcyclohexyl)piperidine, CAS 956-90-1, PCP, I) and many of its analogues have shown some pharmacological effects. In this study, new pyrrole derivatives of I (1-(1-phenylcyclohexyl)pyrrole, II and 1-[1-(4-methylphenyl)(cyclohexyl)]pyrrole, III) and their intermediates were synthesized and the acute and chronic pains were examined on mice using tail immersion (as a model of acute thermal pain) and formalin (as a model of acute and chronic chemical pain) tests and the results were compared with the PCP and control groups. The results indicated that III generated higher analgesic effects in the tail immersion test compared to the PCP and control (dimethyl sulfoxide, DMSO) groups, demonstrating a marked and significant increase in tail immersion latency, but this effect was not observed for II in the dose of 1 mg/kg. The formalin test showed that III was effective in acute chemical pain (phase I, 0-5 min after injection), but was not effective for II at the same dosage compared to the PCP and control groups. Also chronic pain will be significantly attenuated by III but II was not effective as compared to the other groups. It is concluded that substitution of the aromatic pyrrole ring instead of piperidine in the PCP molecule will not be effective alone in tail immersion and formalin tests but the addition of a methyl group (with high electron donating and dipole moments) on the phenyl group plus substitution of the aromatic pyrrole ring can be effective in acute and chronic pain compared to the PCP and control groups. 相似文献