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We describe 2 renal transplant patients with increasing plasma creatinine levels after resolution of acute rejection episodes. Antegrade pyelography demonstrated adherence of the ureter to the inferior pole of the kidney with partial obstruction in both cases, which was confirmed at operation. 相似文献
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Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
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It is known that low glucose concentrations increase the aspartate and decrease the glutamate content of brain tissue both in vivo and in vitro. To see whether these changes occur in the transmitter compartment or not, the release of aspartate and glutamate evoked by electrical-field stimulation or by high K+ was followed in slices of rat hippocampus superfused with 5 or 0.2 mM glucose. Superfusion with 0.2 mM glucose increased the evoked release of aspartate about ten times and that of glutamate about threefold. This shift in the ratio of aspartate to glutamate released was accompanied by a similar increase in the relative amount of aspartate contained in the slices. The high evoked release of aspartate and glutamate was well maintained, provided 0.5 mM glutamine was added to the medium. Changing the concentration of glucose after the first period of stimulation rapidly altered the relative amounts of aspartate and glutamate released but not the enhanced release of glutamate. The large evoked release of both aspartate and glutamate in 0.2 mM glucose was almost entirely Ca2+-dependent. The relative amounts of aspartate and glutamate released by 50 mM K+ also changed when the glucose concentration was reduced. Results suggest two effects of low glucose concentrations: an increase in the overflow of synaptically released glutamate due to a decreased uptake and an increase in the proportion of aspartate to glutamate formed and released from the transmitter pool. These observations are consistent with the interpretation that these two transmitters can be released in different proportions from the same terminals. 相似文献
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Recent studies have suggested that ethanol may exert some of its central depressant actions by increasing the extracellular levels of adenosine in the brain. Ethanol can inhibit the cellular uptake of adenosine, thus increasing its extracellular concentration. After ethanol metabolism by the liver, blood acetate levels are elevated and acetate metabolism in the brain could also lead to the production of adenosine. Rat cerebral cortical cup release experiments failed to reveal any elevation in the extracellular levels of either adenosine or inosine following the intraperitoneal (IP) administration of ethanol (1.5 g/kg) or acetate (2 g/kg). IP-administered ethanol (0.5 and 1.0 g/kg) enhanced the magnitude and duration of the inhibition by iontophoretically applied adenosine of the spontaneous firing of rat cerebrocortical neurons; an action which would be consistent with the block of adenosine uptake. Acetate, applied iontophoretically, depressed the spontaneous firing of 63% of the cerebrocortical neurons tested. 8-p-Sulphophenyltheophylline, an adenosine antagonist, was ineffective at blocking these inhibitions, indicating that adenosine generation is unlikely to have played a major role in the acetate-evoked depression of cerebral cortical neurons. 相似文献
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Variable expression of autosomal recessive polycystic kidney disease and congenital hepatic fibrosis within a family 总被引:2,自引:0,他引:2
B S Kaplan P Kaplan J P de Chadarevian S Jequier S O'Regan P Russo 《American journal of medical genetics》1988,29(3):639-647
Blyth and Ockenden [1971] assigned patients with autosomal recessive polycystic kidney disease (ARPCKD) to 4 discrete groups (perinatal, neonatal, infantile, juvenile) on the basis of the age of presentation. They and others speculated that at least 4 genes were responsible for what they considered to be closely related, but different conditions. These views have gained wide but not universal acceptance. Some workers have insisted that the perinatal and neonatal "forms" of ARPCKD differ fundamentally from the juvenile "form." However, others have proposed that ARPCKD-CHF (congenital hepatic fibrosis) and CHF-ARPCKD are manifestations of the same disease with variation of expression in a kindred. We report on a patient who presented at birth (1979) with ARPCKD and respiratory distress. He died at 18 hr. An older sib presented at 16 yr in 1984. She had no symptoms, but her mother wanted reassurance that the daughter did not have a condition similar to that of the deceased sib. Blood pressure was 120/80 mm Hg and there was hepatosplenomegaly. A diagnosis of renal tubular ectasia and CHF was made by ultrasonography, radiologic studies, and a liver biopsy. The evidence from families such as this favors the concept that ARPCKD and CHF presenting as Blyth and Ockenden's perinatal form, and CHF and renal tubular ectasia as their juvenile form, are manifestations of the same genetic disorder, and that the different manifestations are more likely variations in expression than the results of different mutant genes. The manifestations in this family add weight to the growing body of evidence that intrafamilial variability may occur, not only in autosomal dominant conditions, but also in autosomal recessive disorders. 相似文献
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