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91.
The ocean yacht racing medic: an overview. 总被引:1,自引:0,他引:1
J Campbell Mackenzie 《Journal of the Royal Naval Medical Service》1998,84(2):71-78
92.
Nancy R Sturm Michel Dollet Julius Lukes David A Campbell 《Infection, genetics and evolution》2007,7(5):570-576
The sequences of minicircle conserved regions from various plant trypanosomatids have been determined and analyzed. The goal of this study was to add another tool to the arsenal of molecular probes for distinguishing between the different trypanosomatids occurring in plants: systemic trypanosomatids multiplying in the sap, those from the laticiferous tubes, and those developing in fruits, seeds or flowers but not in the plant itself and that are frequently considered as opportunistic insect trypanosomatids. As some plant intraphloemic trypanosomatids are the causative agents of important diseases, a clear definition of the different types of trypanosomatids is critical. The conserved region of the mitochondrial minicircle provides several specific features in a small sequence region containing three functionally elements required for minicircle replication. Trees generated from the analysis recapitulated trees drawn from analyses of isoenzymes, RAPD, and particular gene sequences, supporting the validity of the small region used in this work. Three groups of isolates were significant and in accordance with previous work. The peculiarity of phloem-restricted trypanosomatids associated with wilts of coconut and oil palm in Latin America - group H - is confirmed. In agreement with previous studies on their biological and serological properties the results highlighted this group called 'phloemicola'. It always differentiated from all other latex and fruit isolates or opportunistic trypanosomatids, like insect trypanosomatids. We can assert that phloemicola is the only well-defined taxon among all plant trypanosomatids. A group of non-pathogenic latex isolates from South American euphorbs (G), and a heterogenous group (A) including one fruit, one possible latex and one insect isolate are clearly distinct groups. The group of Mediterranean isolates from latex (D), even with a low boostrap, stood out well from other groups. The remainder of the isolates fell into a heterogeneous cluster. At least eight different groups in the plant trypanosomatids were identified. 相似文献
93.
Motor map expansion following repeated cortical and limbic seizures is related to synaptic potentiation. 总被引:4,自引:4,他引:0
G Campbell Teskey Marie-H Monfils Penny M VandenBerg Jeffrey A Kleim 《Cerebral cortex (New York, N.Y. : 1991)》2002,12(1):98-105
The effect of experimentally induced seizure activity on the functional reorganization of motor maps has not previously been investigated. Furthermore, while the functional reorganization of motor maps has been thought to involve increases in synaptic communication, there has yet to be a test of this hypothesis. Here we show that repeated seizure activity (kindling), that is accompanied by increased synaptic strength within adult rat motor cortex, results in a doubling of the caudal forelimb motor area. We measured neo-cortical evoked potentials in the right hemisphere prior to 25 days of electrical kindling of the medial frontal corpus callosum or amygdala and re-measured them either 1 or 21 days following the last kindling session. Then, using high resolution intracortical microstimulation (ICMS), the caudal forelimb area in the left hemisphere was mapped. This is the first report of any procedure causing a motor representation to double in size. Furthermore, this expansion was related to the enhanced area of a neocortical polysynaptic field potential and not the motor convulsions per se. Moreover, both the motor map and field potential enhancements were persistent in nature and could be driven from either cortical or limbic sites. The data have implications for human populations with epilepsy. 相似文献
94.
95.
Long-acting dihydropyridine calcium antagonists. 1. 2-Alkoxymethyl derivatives incorporating basic substituents 总被引:4,自引:0,他引:4
J E Arrowsmith S F Campbell P E Cross J K Stubbs R A Burges D G Gardiner K J Blackburn 《Journal of medicinal chemistry》1986,29(9):1696-1702
A series of dihydropyridines substituted at the 2-position by basic side chains are described and their potencies as calcium antagonists listed. One compound, 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5- methoxycarbonyl-6-methyl-1,4-dihydropyridine (17, amlodipine) was found to be comparable in potency to nifedipine and to have an elimination half-life of 30 h in dogs. Oral bioavailability approached 100%, and hemodynamic responses were gradual in onset and long-lasting in effect. The two enantiomers have been prepared, and the bulk of the activity was found to reside with the (-) isomer, 18. X-ray crystallographic studies, carried out on a close analogue of 17, suggest the existence of a weak hydrogen bond between the side-chain oxygen and the proton on the ring nitrogen. 相似文献
96.
To examine the efficacy of modified stroma-free hemoglobin in maintaining liver PO2, rats were exchange-transfused to hematocrit 10% using pyridoxalated polymerized hemoglobin (plp-polyHb, 10-12 g/dl) prepared from crystalline Hb. Following hemodilution, plasma Hb was 7.4 g/dl, and rats were normotensive. Mean liver PO2 was 3.4 vs 23.3 mm Hg in sham-exchanged controls. Other rats, hemodiluted similarly with 6% albumin or hydroxyethylstarch, were hypotensive and died. At 24 hours plasma Hb was 2.0 g/dl, indicating an intravascular half-life of approximately 16 hours. Hepatic PO2 was 12.4 vs 26.8 mm Hg in nonhemodiluted controls. Data provided by clearance of low-dose indocyanine green suggested reduced plasma volume and depressed liver blood flow. Scattered foci of midzonal hypoxic damage were observed in liver lobules. The basis for hypoxic injury is considered to be due in part to the acute restriction of oxygen supply induced by exchange-transfusion with plp-polyHb. The rate of loss of intravascular hemoglobin and diminished plasma volume could have contributed to oxygen insufficiency as well. Endotoxin present in the plp-polyHb was not a factor. 相似文献
97.
B H Campbell B F Dennison G E Durkin M A Strigenz R J Toohill 《Otolaryngology--head and neck surgery》1986,95(5):566-573
There has been widespread use of periodic dilatations in the management of subglottic stenosis. However, some authorities have questioned the value in the overall rehabilitation of patients affected by this disorder. The first phase of this study included fourteen large dogs in which acute subglottic lesions were created by use of a high-speed electric drill and electrocautery. Twelve animals served as the experimental group and two animals were controls. Obstructing lesions developed in all the animals within 7 to 21 days. When at least a 50% obstruction developed in an animal, a treatment plan was instituted that included at least weekly dilatation, removal of granulations, and administration of intralesional steroids and/or systemic steroids and antibiotics. The two control animals became totally obstructed and were killed. Varying degrees of subglottic stenosis developed in all twelve experimental animals after 8 weeks of dilatation, but none required a tracheotomy. These twelve animals were then subjected to 8 additional weeks of dilatation and antibiotics, and supplemental steroids were used in some animals from this study. It can be concluded that early periodic dilatation and granulation removal in the acutely injured subglottis is effective in prevention of severe stenosis, late periodic dilatations in chronic subglottic stenosis are not helpful in further alleviation of obstruction, the concomitant use of antibiotics and systemic steroids did not appreciably prevent or alter the development of subglottic stenosis, and the concomitant use of intralesional steroids appeared to be of benefit in the management of chronic acquired subglottic stenosis. 相似文献
98.
Case-control study of prenatal ultrasonography exposure in children with delayed speech. 总被引:2,自引:0,他引:2 下载免费PDF全文
OBJECTIVE: To determine whether there is an association between prenatal ultrasound exposure and delayed speech in children. DESIGN: Case-control study. SETTING: Network of community physicians affiliated with the Primary Care Research Unit, University of Calgary. SUBJECTS: Thirty-four practitioners identified 72 children aged 24 to 100 months who had undergone a formal speech-language evaluation and were found to have delayed speech of unknown cause by a speech-language pathologist. For each case subject the practitioners found two control subjects matched for sex, date of birth, sibling birth order and associated health problems. MAIN OUTCOME MEASURES: Rates of prenatal ultrasound exposure and delayed speech. RESULTS: The children with delayed speech had a higher rate of ultrasound exposure than the control subjects. The findings suggest that a child with delayed speech is about twice as likely as a child without delayed speech to have been exposed to prenatal ultrasound waves (odds ratio 2.8, 95% confidence limit 1.5 to 5.3; p = 0.001). CONCLUSION: An association between prenatal ultrasonography exposure and delayed speech was found. If there is no obvious clinical indication for diagnostic in-utero ultrasonography, physicians might be wise to caution their patients about the vulnerability of the fetus to noxious agents. 相似文献
99.
Mazin A.I. Sarsam F.R.C.S. Colin S. Campbell F.R.C.S. Nizar A. Yonan F.R.C.S. Abdul K. Deiraniya F.R.C.S. Ali N. Rahman F.R.C.S. 《Journal of cardiac surgery》1993,8(3):344-349
A bstract Forty patients underwent orthotopic cardiac transplantation at Wythenshawe Hospital between May 1991 and November 1992. Twenty patients had transplantation using an alternative technique that preserves the shape of the left atrium and leaves the right atrium intact (group A). The remaining twenty had conventional transplantation using the technique described by Lower and Shumway (group B). The patients were randomized to either the new or the conventional technique on an alternate basis. There was no mortality in group A, but two patients in group B developed right ventricular failure and died. Two patients in each group developed nodal rhythm and all four recovered sinus rhythm. Echocardiography and Doppler velocimetry at the transvalvular level confirmed normal atrial function in group A with erratic atrial contraction wave in group B. There was also slightly lower incidence of mitral and tricuspid valve regurgitation in group A than in group B. The improved atrial function in group A may play a part in the prevention of right sided failure following cardiac transplantation. 相似文献
100.
Effect of endothelium on beta-VLDL metabolism by cultured smooth muscle cells of differing phenotype 总被引:1,自引:0,他引:1
The effect of endothelial cells (EC) on the binding and internalisation of beta-very low density lipoprotein (beta-VLDL) and the subsequent accumulation of lipid was investigated in cultured smooth muscle cells (SMC) of different phenotype. The following combinations were examined: (i) SMC cultured and incubated with 125I-beta-VLDL without EC: "control" cultures; (ii) SMC co-cultured with EC and incubated with 125I-beta-VLDL without EC: "separated" cultures; and (iii) SMC co-cultured with EC and incubated with 125I-beta-VLDL in the presence of EC: "co-incubated" cultures. SMC were in the contractile (CON), reversible synthetic (RS) or irreversible synthetic (IRS) phenotype and EC were either actively proliferating or confluent and quiescent. All three SMC phenotypes showed the greatest capacity to bind and internalise 125I-beta-VLDL with accumulation of lipid when "co-incubated" with confluent EC. SMC "co-incubated" with proliferating EC showed a lower capacity to bind and internalise the lipoprotein and accumulate lipid, while "control" SMC showed the lowest capacity for all phenotypes. IRS SMC bound more 125I-beta-VLDL than either RS or CON state phenotypes. In addition, IRS SMC "co-incubated" with confluent EC showed the greatest degree of binding, and IRS SMC incubated with EC-conditioned medium and EC-conditioned 125I-beta-VLDL showed a significant increase in binding above control (fresh medium and fresh 125I-beta-VLDL). The degree of binding 125I-beta-VLDL to SMC was affected by the functional state of the EC. That is, SMC "co-incubated" with confluent EC bound more lipoprotein than SMC "co-incubated" with the same number of proliferating EC. These results are consistent with observations by others who report preferential lipid accumulation in regions of denuded artery recently recovered by endothelium compared with regions lacking an endothelium. The results also indicate that the EC both modify the beta-VLDL particle and affect the biology of the SMC themselves. 相似文献