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61.
Corticosteroid Supplementation for Adrenal Insufficiency 总被引:2,自引:0,他引:2
62.
A Misbahuddin M R Placzek K R Chaudhuri N W Wood K P Bhatia T T Warner 《Neurology》2002,58(1):124-126
Abnormalities in dopamine neurotransmission are thought to underlie the generation of dystonic movements. The authors performed a case-control allelic association study in patients with the focal dystonia blepharospasm, using polymorphisms in the dopamine receptor and transporter genes. Allele 2 of a DRD5 dinucleotide repeat was significantly associated with blepharospasm. This may indicate a pathogenic role for this receptor. 相似文献
63.
Double-crush nerve compression in thoracic-outlet syndrome 总被引:5,自引:0,他引:5
We studied 165 cases of thoracic-outlet syndrome in 142 patients in whom resection of the first rib had been performed. In seventy-three cases (44 per cent), there was compression of a nerve distally, as shown by electromyography and conduction studies. The most common secondary compression was carpal tunnel syndrome (forty-one cases). Thirteen patients needed an operation at three sites or more. Our results show that proximal compression of a nerve lessens its ability to withstand more distal compression. Once the diagnosis of thoracic-outlet syndrome has been made, the possibility of an additional distal compression neuropathy should be investigated. 相似文献
64.
Splenectomy and renal allograft survival in the rat 总被引:1,自引:0,他引:1
The effect of splenectomy on renal allograft survival is not clear. In the rat, spleens isolated from recipients with functioning grafts have been shown to be a major source of cells that are capable of suppressing the rejection response (suppressor T lymphocytes). Thus the removal of the spleen in these allograft recipients could be detrimental to renal allograft survival. This study investigates this hypothesis, and looks for the presence of suppressor cells in other lymphoid organs apart from the spleen. In the rat renal allograft model, donor Lewis spleen cells given to DA recipients intravenously 1 week before transplantation of a Lewis kidney leads to indefinite allograft survival (median survival time (MST) greater than 100 days). Splenectomy before or after pretreatment with donor spleen cells failed to abrogate this effect (MST greater than 100 days). Experiments were performed in which cells or serum were prepared from long-term surviving splenectomized animals which had already been pretreated and transplanted, and then were injected into untreated recipients (adoptive transfer experiments). This was done to determine if cells capable of suppressing graft rejection were present in lymphoid organs outside the spleen in these splenectomized recipients. Thus the IV transfer of 10(8) lymph node cells harvested from splenectomized DA recipients with a long-term surviving LEW graft (LTS), into untreated but lightly irradiated (200 rad) DA recipients resulted in indefinite survival of a fresh Lewis kidney (MST greater than 100 days). In contrast, adoptive transfer of normal DA lymph node cells was ineffective (MST 13 days). Thus splenectomy is not necessarily detrimental to graft survival, as cells capable of preventing graft rejection are found in other lymphoid organs, such as lymph nodes, in splenectomized recipients. 相似文献
65.
B A John L F Chasseaud S G Wood P Forlot 《Xenobiotica; the fate of foreign compounds in biological systems》1992,22(11):1339-1351
1. Single oral doses of 14C-5-methoxypsoralen (5-MOP) to human subjects (50 mg), rats (1 mg/kg) and dogs (1 mg/kg) were fairly well absorbed but subjected to extensive first-pass metabolism, at least in rat and human. Means of 62, 51 and 40% dose in urine and 31, 38 and 48% dose in faeces, were excreted by humans (during 5 days), rats (3 days) and dogs (1 day), respectively. In dogs, faecal 14C was probably derived, in part, from biliary excreted material. 2. Total 14C in human plasma reached peak concentrations after 2 h (mean 235 ng 5-MOP equivalent/ml) and declined relatively slowly, to about 60% of this value within 24 h. Unchanged 5-MOP was not detected in plasma using h.p.l.c. (< 5 ng/ml). 3. Tissue concentrations of 14C were generally greater in dogs than rats and reached peak levels at 1 h in dogs but at 24 h in rats. Apart from liver and bile, dog tissue 14C concentrations were lower than those in the corresponding plasma, whereas in rat they were lower only until the time of peak concentrations, after which they were generally greater. 4. 5-MOP was extensively metabolized in all three species. The major 14C-components in human and dog urine were glucuronic acid conjugates, mainly of an arylacetic acid and arylalcohols, resulting from initial oxidative metabolism of the furan ring of 5-MOP. In rat, these metabolites were excreted mainly unconjugated. An unusual metabolite was formed by reduction of the lactone moiety of 5-MOP, probably by the gut flora, giving rise to an arylpropionic acid, excreted as a glucuronic acid conjugate in the urine of all three species. 5. Unchanged drug was a very minor component of human and rat plasma, but a major component of dog plasma. In all three species, circulating 14C-metabolites were similar to those in the urine but were present mainly unconjugated. On the basis of these data, the metabolic fate of 5-MOP in humans was more similar to that in dog than to that in rat, although humans appeared to metabolize 5-MOP more rapidly than did dog. 相似文献
66.
P J Wood I J Stratford J M Sansom B M Cattanach R M Quinney G E Adams 《International journal of radiation oncology, biology, physics》1992,22(3):473-476
31P magnetic resonance spectroscopy has been used to compare the effects of the vasoactive agents hydralazine and flunarizine on the oxygenation of the transplantable tumors, SCCVII/Ha and 16C, and a range of spontaneous mammary tumors arising in the breeding stock in the Genetics Division at the Radiobiology Unit. The vasodilator hydralazine, previously shown to increase the radiobiological hypoxic fraction of transplantable murine tumors, increased inorganic phosphate to total phosphate (Pi/total) in SCCVII/Ha and 16C tumors. However, only two spontaneous tumors responded to this agent (2/12). The calcium antagonist flunarizine, which sensitizes the SCCVII tumor to X rays, consistent with a reduction in hypoxic fraction, reduced Pi/total in this and the 16C tumor. Further, most spontaneous tumors tested (8/10) responded to this agent, as measured by a reduction in Pi/total. These results point to fundamental differences between transplantable and spontaneously arising tumors in mice in their response to vasoactive agents. 相似文献
67.
68.
In this admittedly preliminary view of the future, the authors present a number of new concepts in MR imaging and consider their possible advantages and limitations. 相似文献
69.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency. 相似文献
70.
DQ beta restriction fragment patterns have been obtained from five DRw8 cell lines homozygous for the null DQ allele, DQWa. The enzymes Bgl II, Bam HI and Pvu II generate DQ beta patterns which are indistinguishable from those obtained from cell lines homozygous for DQw3.2. 相似文献