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991.
Antigens of aspergillus fumigatus. 1. Purification of a cytoplasmic antigen reactive with sera of patients with aspergillus-related disease. 总被引:2,自引:3,他引:2 下载免费PDF全文
N J Calvanico B L Du Pont C J Huang R Patterson J N Fink V P Kurup 《Clinical and experimental immunology》1981,45(3):662-671
An antigen has been purified from the mycelial cell sap of Aspergillus fumigatus (strain 507). The same component appears to be present in the extracellular phase (culture filtrate) in a partially degraded form. The cell sap protein has a structure composed of four polypeptides of 45,000 daltons linked through disulphide bonds. The isoelectric point (5.2-5.6) and carbohydrate content (12.5% neutral hexose) indicate that this protein is an acidic glycoprotein. It shows reactions with 75% of sera from patients with aspergilloma and allergic bronchopulmonary aspergillosis and is not reactive with sera from normal individuals of patients with other fungal diseases. It also appears to be a component of other A. fumigatus strains. 相似文献
992.
J R Haywood R A Shaffer C Fastenow G D Fink M J Brody 《The American journal of physiology》1981,241(2):H273-H278
Development of techniques for the continuous measurement of regional blood flow and vascular resistance in intact small animals has been impeded primarily by the bulkiness of flow probes. The availability of an ultrasonic pulsed Doppler flowmeter system enabled us to construct miniaturized probes using 1-mm-diameter piezoelectric crystals that emit a 20-mHz signal and receive the reflected sound waves from passing blood cells. The finished flow probe is approximately 2.5-4 mm long and 2 mm in cross-sectional diameter with lumen diameters appropriate for the rat, ranging from 0.7 to 1.2 mm. This report describes the materials and methods involved in constructing and implanting the probes in rats to monitor renal, mesenteric, and hindquarter blood flow velocity. The accuracy of the pulsed Doppler method in detecting changes in regional blood flow and vascular resistance was established by the demonstration of a highly significant correlation between velocity recorded from the Doppler unit and volume flow recorded simultaneously. These data indicate that the ultrasonic pulsed Doppler flowmeter provides the opportunity to measure changes in regional blood flow and vascular resistance in a conscious freely moving rat. 相似文献
993.
Lise Høj Thomsen Lisbeth Nielsen Fink Jenny Norlin Amaya García de Vinuesa Troels Krarup Hansen 《Renal failure》2017,39(1):629-642
Uncontrolled activation of transforming growth factor beta (TGF-β) family members is hypothesized to participate in type 2 diabetes (T2D) dependent diabetic nephropathy (DN). We evaluated and compared downstream activation of the Smad2-signaling pathway in kidney samples from T2D patients to kidneys from the T2D model of leptin receptor deficient db/db mouse. Furthermore, expression of TGF-β family members was evaluated to elucidate molecular mechanisms in the mouse model. Kidney samples from patients with advanced stages of DN showed elevated pSmad2 staining whereas db/db mouse kidneys surprisingly showed a decrease in pSmad2 in the tubular compartment. Structurally, kidney tissue showed dilated tubules and expanded glomeruli, but no clear fibrotic pattern was found in the diabetic mice. Selective TGF-β family members were up-regulated at the mRNA level. Antagonists of bone morphogenetic protein (BMP) ligands, such as Gremlin1, USAG1 and Sclerostin, were strongly up-regulated suggesting a dampening effect on BMP pathways. Together, these results indicate a lack of translation from T2D patient kidneys to the db/db model with regards to Smad signaling pathway. It is plausible that a strong up-regulation of BMP antagonizing factors account for the lack of Smad1/5/8 activation, in spite of increased expression of several BMP members. 相似文献
994.
995.
Jennifer L. W. Fink 《Cancer》2016,122(23):3589-3590
996.
Rationale Adaptation to stressful situations changes with increasing age. This is also reflected in age-related differences in effects
of acute stress on, e.g., episodic memory. Less is known about age-related differences of the cognitive effects of individual
stress responses to challenging situations.
Objective To investigate the influence of the individual cortisol response (as a marker for the individual stress level) on behavioral
and neural measures during a challenging memory paradigm.
Materials and methods Twenty young and 12 older subjects were scanned using functional magnetic resonance imaging during encoding and retrieval
of spatial contextual information. Salivary cortisol levels were measured before and after scanning.
Results A multiple regression analysis of behavioral data showed an interaction effect of age and cortisol response on memory for
the items and their spatial context during retrieval due to increased accuracy with increasing cortisol responses in young
compared to old subjects. During encoding, this was reflected in a positive effect of the cortisol response on prefrontal
activity in young but not in older subjects. During retrieval, there was a negative effect of the cortisol response on brain
activity in the hippocampus and prefrontal regions in older but not in young subjects.
Conclusions The data suggest an increased efficiency to encode items and their context with increasing cortisol responses in young subjects,
and a decreased efficiency to retrieve information with increasing cortisol responses in older subjects. We conclude that
neuroendocrine responses are differentially associated with behavioral and neural measures in cognitively challenging situations
in young and older volunteers.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
997.
Ryan M. Degen Matthew E. Fink Lisa Callahan Kenton H. Fibel Jim Ramsay Bryan T. Kelly 《The Physician and sportsmedicine》2016,44(3):324-326
Head injuries are relatively common in ice hockey, with the majority represented by concussions, a form of mild traumatic brain injury. More severe head injuries are rare since the implementation of mandatory helmet use in the 1960s. We present a case of a 27 year-old male who sustained a traumatic intraparenchymal hemorrhage with an associated subdural hematoma resulting after being struck by a puck shot at high velocity. The patient presented with expressive aphasia, with no other apparent neurologic deficits. Acutely, he was successfully treated with observation and serial neuroimaging studies ensuring an absence of hematoma expansion. After a stable clinical picture following 24 hours of observation, the patient was discharged and managed with outpatient speech therapy with full resolution of symptoms and return to play 3 months later. We will outline the patient presentation and pertinent points in the management of acute head injuries in athletes. 相似文献
998.
Occurrence,genotypic characterization,and patterns of shedding of human polyomavirus JCPyV and BKPyV in urine samples of healthy individuals in São Paulo,Brazil 下载免费PDF全文
999.
Paulo Roberto P. Urbano Luiz H. da Silva Nali Renato dos R Oliveira MS Laura M. Sumita Maria Cristina D. da Silva Fink Lígia C Pierrotti MD MS Camila da Silva Bicalho Elias David-Neto MD Cláudio S. Pannuti MD Camila M Romano 《Journal of medical virology》2019,91(6):1136-1141
BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients’ infection. 相似文献
1000.