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101.
Oosterhuis GJ Mulder AB Kalsbeek-Batenburg E Lambalk CB Schoemaker J Vermes I 《Fertility and sterility》2000,74(2):245-250
OBJECTIVE: [1] To determine whether apoptosis can be measured in ejaculated spermatozoa by flow cytometry using the Annexin V assay, which measures expression of phosphatidylserine on the outer leaflet of the cell membrane, or the TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP [deoxy-uridine triphosphate] nick end labeling) assay, which measures occurrence of DNA strand breaks and [2] to correlate the outcome with routine semen variables and the hypoosmotic swelling (HOS) test. DESIGN: Pilot study and clinical trial. SETTING: Large teaching hospital and fertility center. PATIENT(S): Men whose semen was studied for various reasons. MAIN OUTCOME MEASURE(S): Percentage of apoptotic spermatozoa by two different assays, percentage of necrotic spermatozoa, concentration and motility of spermatozoa, and outcome of the HOS test. RESULT(S): Apoptosis can be measured in spermatozoa by flow cytometry using the Annexin V assay and the TUNEL assay. Twenty percent of spermatozoa were apoptotic according to both assays. A significant inverse correlation was seen between phosphatidylserine expression (Annexin V assay) and sperm concentration (r = -0.389; P<.05) and motility (r = -0.289; P<.05). A highly significant inverse correlation was seen between DNA double-strand breaks (TUNEL assay) and sperm concentration (r = -0.629; P<.0001). CONCLUSION(S): Flow cytometry can easily and reliably detect phosphatidylserine expression on the outer leaflet of the cell membrane and DNA strand breaks, both of which are hallmarks of apoptosis. About 20% of ejaculated spermatozoa are apoptotic, and the concentration of spermatozoa is lower in men with more apoptotic spermatozoa. 相似文献
102.
Joanne K. Marcario Mariam Riazi Istvan Adany Himanshu Kenjale Kandace Fleming Janet Marquis Olga Nemon Matthew S. Mayo Thomas Yankee Opendra Narayan Paul D. Cheney 《Journal of neuroimmune pharmacology》2008,3(1):12-25
Morphine is known to prevent the development of cell-mediated immune (CMI) responses and enhance expression of the CCR5 receptor
in monocyte macrophages. We undertook a study to determine the effect of morphine on the neuropathogenesis and immunopathogenesis
of simian immunodeficiency virus (SIV) infection in Indian Rhesus Macaques. Hypothetically, the effect of morphine would be
to prevent the development of CMI responses to SIV and to enhance the infection in macrophages. Sixteen Rhesus Macaques were
divided into three experimental groups: M (morphine only, n = 5), VM (morphine + SIV, n = 6), and V (SIV only, n = 5). Animals in groups M and VM were given 2.5 mg/kg of morphine sulfate, four times daily, for up to 59 weeks. Groups VM
and V were inoculated with SIVmacR71/17E 26 weeks after the beginning of morphine administration. Morphine prevented the development
of enzyme-linked immunosorbent spot-forming cell CMI responses in contrast to virus control animals, all of which developed
CMI. Whereas morphine treatment had no effect on viremia, cerebrospinal fluid viral titers or survival over the time course
of the study, the drug was associated with a tendency for greater build-up of virus in the brains of infected animals. Histopathological
changes in the brains of animals that developed disease were of a demyelinating type in the VM animals compared to an encephalitic
type in the V animals. This difference may have been associated with the immunosuppressive effect of the drug in inhibiting
CMI responses. 相似文献
103.
C Vermes K A Roebuck R Chandrasekaran J G Dobai J J Jacobs T T Glant 《Journal of bone and mineral research》2000,15(9):1756-1765
104.
International Journal of Clinical Pharmacy - 相似文献
105.
Kindling-induced epilepsy alters calcium currents in granule cells of rat hippocampal slices 总被引:2,自引:0,他引:2
Istvan Mody James N. Reynolds Michael W. Salter Peter L. Carlen John F. MacDonald 《Brain research》1990,531(1-2):88-94
Single electrode voltage-clamp recordings were obtained from dentate gyrus granule cells (GCs) in hippocampal slices of control and commissurally kindled rats. Two types of calcium currents, a transient and a sustained current, were studied in control and kindled neurons. The threshold of the transient calcium current was lowered in kindled GCs. The sustained calcium current was absent in kindled neurons but it could be restored by the intracellular administration of the calcium chelator EGTA. Our findings are consistent with the hypothesis that the loss of an intraneuronal calcium binding protein (Calbindin-D28K; CaBP) reduces the intraneuronal calcium buffering capacity in kindled neurons and results in the enhanced calcium-dependent inactivation of sustained calcium currents. 相似文献
106.
107.
Dr Prof Bernard Escudier MD Prof Anna Pluzanska MD Piotr Koralewski MD Prof Alain Ravaud MD Prof Sergio Bracarda MD Prof Cezary Szczylik MD Christine Chevreau MD Marek Filipek MD Bohuslav Melichar MD Prof Emilio Bajetta MD Prof Vera Gorbunova MD Jacques-Olivier Bay MD Istvan Bodrogi MD Agnieszka Jagiello-Gruszfeld MD Nicola Moore MSc for the AVOREN Trial investigators 《Lancet》2008,370(9605):2103-2111
108.
109.
Watching social interactions produces dorsomedial prefrontal and medial parietal BOLD fMRI signal increases compared to a resting baseline 总被引:5,自引:0,他引:5
Iacoboni M Lieberman MD Knowlton BJ Molnar-Szakacs I Moritz M Throop CJ Fiske AP 《NeuroImage》2004,21(3):1167-1173
Some human brain areas are tonically active in a resting state when subjects are not engaged in any overt task. The activity of these areas decreases when subjects are engaged in a wide variety of laboratory tasks designed to study cognitive operations. It has been suggested that these areas, among them the medial parietal (precyneus) and the dorsomedial prefrontal cortices, may support a "default state" of the human brain. Passive visual observation of laboratory stimuli typically yields no change in activity in these default areas compared to rest. Here we report functional magnetic resonance imaging (fMRI) data on normal subjects watching realistic movie clips depicting everyday social interactions. In contrast with previous findings on default state brain areas, the observation of the relational segment of the movie clip, during which two persons interact, yielded increased activity in the medial parietal (precuneus) and dorsomedial prefrontal cortices, compared to rest and to observation of the segment of the movie clip depicting a single individual engaged in everyday activities. To the best of our knowledge, this is the first report of joint increased activity in medial parietal and dorsomedial prefrontal cortices. We suggest that the default state areas may participate in the processing of social relations in concert with regions previously identified as critical for social cognition that were also activated by our stimuli, including the inferior frontal cortex, the superior temporal cortex, and the fusiform gyrus. 相似文献
110.
Timing of therapeutic intervention determines functional and survival outcomes in a mouse model of late infantile batten disease. 总被引:1,自引:0,他引:1
Mario A Cabrera-Salazar Eric M Roskelley Jie Bu Bradley L Hodges Nelson Yew James C Dodge Lamya S Shihabuddin Istvan Sohar David E Sleat Ronald K Scheule Beverly L Davidson Seng H Cheng Peter Lobel Marco A Passini 《Molecular therapy》2007,15(10):1782-1788
Classical late infantile neuronal ceroid lipofuscinosis (cLINCL) is a monogenic disorder caused by the loss of tripeptidyl peptidase 1 (TPP1) activity as a result of mutations in CLN2. Absence of TPP1 results in lysosomal storage with an accompanying axonal degeneration throughout the central nervous system (CNS), which leads to progressive neurodegeneration and early death. In this study, we compared the efficacies of pre- and post-symptomatic injections of recombinant adeno-associated virus (AAV) for treating the cellular and functional abnormalities of CLN2 mutant mice. Intracranial injection of AAV1-hCLN2 resulted in widespread human TPP1 (hTPP1) activity in the brain that was 10-100-fold above wild-type levels. Injections before disease onset prevented storage and spared neurons from axonal degeneration, reflected by the preservation of motor function. Furthermore, the majority of CLN2 mutant mice treated pre-symptomatically lived for at least 330 days, compared with a median survival of 151 days in untreated CLN2 mutant controls. In contrast, although injection after disease onset ameliorated lysosomal storage, there was evidence of axonal degeneration, motor function showed limited recovery, and the animals had a median lifespan of 216 days. These data illustrate the importance of early intervention for enhanced therapeutic benefit, which may provide guidance in designing novel treatment strategies for cLINCL patients. 相似文献