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I. Tsunoda Yuzo Iwasaki Hiroshi Terunuma Kazuya Sako Yoshiro Ohara 《Acta neuropathologica》1996,91(6):595-602
Theiler’s murine encephalomyelitis viruses (TMEV) are divided into two subgroups on the basis of their different biological
activities. The GDVII strain produces acute polioencephalomyelitis in mice, whereas the DA strain produces demyelination with
virus persistence in the spinal cord. A comparative study of GDVII and DA strains suggested that low host immune responses
are responsible for the development of acute GDVII infection and that the persistence of infected macrophages plays a crucial
role in the development of chronic white matter lesions in DA infection. All 78 mice infected with GDVII died or became moribund
by day 13, while none of 54 mice infected with DA died. In the acute stage, the distribution of viral antigens in the central
nervous system (CNS) tissue was similar in both GDVII and DA infections, although the virus titer was higher in GDVII infection.
In DA infection, a substantial number of T cells were recruited to the CNS on day 6 when they were virtually absent in GDVII
infection. The titer of neutralizing antibody was already high on day 6 in DA infection but was negligible in GDVII infection.
Development of chronic paralytic disease from day 35 of the DA infection was accompanied by focal accumulation of viral antigen-positive
macrophages in the spinal white matter. In addition, white matter lesions comparable to those in chronic DA infection were
induced in the spinal cord within 7 days after intracerebral injection of DA-infected murine macrophages.
Received: 26 June 1995 / Revised, accepted: 27 December 1995 相似文献
5.
Kiyoshi Nakatsuka Yoshiki Nishizawa Satoshi Hagiwara Hidenori Koyama Takami Miki Hironobu Ochi Hirotoshi Morii 《Calcified tissue international》1990,47(6):378-382
Summary Total body bone mineral (TBBM) content in rats was measured by dual photon absorptiometry (DPA). TBBM showed significant increases
over 4 weeks in control groups with significant bone loss over the same time in prednisolone-injected rats on low calcium
feed. Daily injections of calcitonin significantly reduced loss of bone mass. Both prednisolone- and prednisolone-calcitonin-injected
groups showed significantly elevated serum alkaline phosphatase with the prednisolone-calcitonin group also exhibiting elevated
serum calcium and phosphate levels, confirming the impact of the experimental protocol. TBBM measured by DPA in all groups
correlated well (r=0.928,P<0.001 n=20) with the total ash weight suggesting that the method reflects total skeletal mineral content in the small animal.
TBBM measurement by DPA proves well-suited to monitoring bone mineral in a small animal experimental setting. 相似文献
6.
Usefulness of magnetic motor evoked potentials in the surgical treatment of hemiplegic patients with intractable epilepsy. 总被引:2,自引:0,他引:2
Tohru Kamida Hiroshi Baba Kenji Ono Masato Yonekura Minoru Fujiki Hidenori Kobayashi 《Seizure》2003,12(6):373-378
Five hemiplegic patients with intractable epilepsy were studied with transcranial magnetic stimulation (TMS) before and after various surgical treatments. These patients had unilateral widespread cerebral lesions acquired at various times, including congenital, infantile and childhood injury. Motor evoked potentials (MEPs) of the abductor pollicis brevis (APB) muscles were simultaneously recorded on both sides following TMS of the motor cortex in the respective hemisphere using a figure-8 or circular coil. In all patients with congenital disease, the abolition of motor function in the affected hemisphere was estimated by magnetic MEPs, and the hemiplegia did not deteriorate after functional hemispherectomy (HS) was performed in two of them. In two patients with acquired disease, HS was not performed because it was shown by magnetic maps that the motor function in the affected hemisphere remained. Furthermore, it was shown by electric MEPs using subdural electrodes that a patient who had had encephalitis in early childhood had a reorganised motor area in the parietal cortex of the affected hemisphere. The present findings indicate that magnetic MEPs are a very useful non-invasive method of assessing whether the motor area in the affected hemisphere can be resected in hemiplegic patients with intractable epilepsy. 相似文献
7.
Protein kinase C (PKC) activity was measured in rat brain with 2 h of middle cerebral artery (MCA) and common carotid artery (CCA) occlusion, using dual autoradiography of [14C]iodoantipyrine (IAP) and [3H]phorbol-12,13-dibutyrate (PDBu). In the ischemic brain, it required more than 120 min of incubation to obtain a plateau in PDBu binding. In contrast, the binding of PDBu in non-ischemic brain reached a plateau with incubation for 60 min. This delay of PDBu binding in the ischemic brain suggests that the affinity of this ligand is reduced due to a change in structure of the cell membrane caused by ischemia. PDBu binding in the ischemic brain increased significantly compared to the non-ischemic brain. This finding provides further evidence that excessive activation of PKC in the ischemic brain may play an important role in ischemic neuronal damage. ©1997 Elsevier Science B.V. All rights reserved. 相似文献
8.
Yoshinori Yamashita Toshihiro Hirai Hidenori Mukaida Takashi Iwata Tetsuya Toge Hong Jae Hoon 《Surgery today》1990,20(6):671-676
This report presents the effect of repeated heating every 24 hrs using bleomycin (BLM) which, although seemingly contrary
to the usual agreement that hyperthermia should be carried out with a long interval due to thermotolerance, holds many possibilities.
FM3A cells on the foot pad of C3H mouse were immersed in a heated water bath at 43 and 44°C for 30 min. The effect of repeated
heating was appreciated by an improved growth curve and 50 day survival compared to mice which received heating twice with
a 96-hr interval. Repeated heating every 24 hrs 5 times with BLM suppressed tumor growth significantly as compared to heating
twice with a 96-hr interval without BLM. The longest survival time was obtained by the repeated heating with BLM among all
protocols. There is therefore a good possibility that more effective results could be obtained clinically by repeated heating
over a short period. 相似文献
9.
HA1077, a novel calcium antagonistic antivasospasm drug, increases both cerebral blood flow and glucose metabolism in conscious rats. 总被引:1,自引:0,他引:1
The effects of a novel calcium antagonistic antivasospasm drug, HA1077, on local cerebral blood flow (LCBF) and local cerebral glucose utilization (LCGU) were studied in 33 anatomically discrete regions of the brain in conscious rats, using the quantitative autoradiographic [14C]iodoantipyrine and [14C]2-deoxyglucose techniques. HA1077 was infused i.v. over a 30-min period (1 or 3 mg/kg). HA1077 significantly increased LCBF in 9 of 33 sites in rats given 1 mg/kg, and in 14 of 33 sites in rats given 3 mg/kg compared to the control group given vehicle. Significant increases in LCGU were also noted in 16 of 33 sites in rats given 3 mg/kg. HA1077 increased both cerebral blood flow and glucose metabolism in conscious rats. 相似文献
10.
Hidenori Endo Chikako Nito Hiroshi Kamada Tatsuro Nishi Pak H Chan 《Journal of cerebral blood flow and metabolism》2006,26(12):1479-1489
Recent studies have revealed that the phosphatidylinositol 3-kinase (PI3-K) pathway is involved in apoptotic cell death after experimental cerebral ischemia. The serine-threonine kinase, Akt, functions in the PI3-K pathway and prevents apoptosis by phosphorylation at Ser473 after a variety of cell death stimuli. After phosphorylation, activated Akt inactivates other apoptogenic factors, including glycogen synthase kinase-3beta (GSK3beta), thereby inhibiting cell death. However, the role of Akt/GSK3beta signaling in the delayed death of hippocampal neurons in the CA1 subregion after transient global cerebral ischemia (tGCI) has not been clarified. Transient global cerebral ischemia for 5 mins was induced by bilateral common carotid artery occlusion combined with hypotension. Western blot analysis showed a significant increase in phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) in the hippocampal CA1 subregion after tGCI. Immunohistochemistry showed that expression of phospho-Akt (Ser473) and phospho-GSK3beta (Ser9) was markedly increased in the vulnerable CA1 subregion, but not in the ischemic-tolerant CA3 subregion. Double staining with phospho-GSK3beta (Ser9) and terminal deoxynucleotidyl transferase-mediated uridine 5'-triphosphate-biotin nick end labeling showed different cellular distributions in the CA1 subregion 3 days after tGCI. Phosphorylation of Akt and GSK3beta was prevented by LY294002, a PI3-K inhibitor, which facilitated subsequent DNA fragmentation 3 days after tGCI. Moreover, transgenic rats that overexpress copper/zinc-superoxide dismutase, which is known to be neuroprotective against delayed hippocampal CA1 injury after tGCI, had enhanced and persistent phosphorylation of both Akt and GSK3beta after tGCI. These findings suggest that activation of the Akt/GSK3beta signaling pathway may mediate survival of vulnerable hippocampal CA1 neurons after tGCI. 相似文献