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71.
The occurrence of preferential repair in Saccharomyces cerevisiaeof the active MAT locus compared with the inactive HML locuswas confirmed after 254 nm UV irradiation. Experiments carriedout using the UvrABC excinuclease assay with the monofunctionalfurocoumarin 3-carbethoxypsoralen (3-CPs) plus UVA radiationwhich induce mainly monoadducts in DNA demonstrated preferentialrepair of the active MAT locus compared with the inactive HMLlocus in a SIR+ strain. However, as after 254 nm UV irradiation,no difference in the rate of removal of 3-CPs plus UVA inducedlesions was observed between the two loci in the sir-3 mutantin which both loci are active. Thus, it appears that 3-CPs plusUVA induced monoadducts as well as pyrimidine dinners a e subjectto preferential repair.
3To whom correspondence should be addressed 相似文献
72.
Arne Simon Roland A. Ammann Anja Wilkesmann Anna M. Eis-Hübinger Oliver Schildgen et al. 《Infection》1993,21(1):39-39
Information
The 11th Meeting of the European Society for Paediatric Infectious Diseases (ESPID) 26–28 May 1993 Helsinki, Finland 相似文献73.
Jürgen Thomale Arne Luz Gisela Nass 《Journal of cancer research and clinical oncology》1984,108(3):302-307
Summary During x-ray-induced development of malignant lymphomas in mice their urinary excretion of eight modified nucleosides was monitored and the values were compared to the results of the histological examination of the animals at time of their sacrifice.It was found that the pathologically augmented excretion of modified nucleosides begins as much as several weeks before the malignant lymphomas can be diagnosed clinically. Thus some mice had increased levels of modified nucleosides even 10 weeks before sacrifice, though at the time of sacrifice the histological investigation reveled only some small foci of reticulum cell neoplasm in their spleen.It is therefore stressed that the usefulness of the determination of urinary modified nucleosides as an early noninvasive screening test for cancer in man and as an in vivo carcinogenicity test should be evaluated.Abbreviations
pseudouridine
- m1A
1-methyladenosine
- m5C
5-methylcytidine
- m1I
1-methylinosine
- m1G
1-methylguanosine
- m2G
N
2-methylguanosine
- m2G
N
2,N2-dimethylguanosine
- ac4C
N
4-acetylcytidine
- mt6A
N-(9--d-ribofuranosylpurine-6-yl)N-methylcarbamoyl) threonine
- acp3U
3-(3-amino-3-carboxypropyl) uridine
- SD
standard deviation 相似文献
74.
75.
Hans Christian Blossey Hans Helge Bartsch Dietrich Kanne Johannes Koebberling Gerhard Arno Nagel 《Cancer chemotherapy and pharmacology》1982,8(1):77-81
Summary Oral MPA 1.5 g/day leads to plasma concentrations between 1 and 12 g/ml, with a broad intra-and interindividual variance. The plateau state is reached in between 4 and 16 days. Plasma concentrations in the plateau state are very sensitive to dose modifications. After cessation of administration, the decline in plasma levels seems to proceed in two phases, with half-times of about 20 h and 4 days. Extraction procedures reveal no benefit in discriminating between MPA and its metabolites. 相似文献
76.
We describe two patients with subarachnoid haemorrhage due to a ruptured intracranial aneurysm and severe symptomatic vasospasm.
The aneurysm was occluded with detachable coils followed by intra-arterial infusion of papaverine to treat vasospasm as an
one-stage procedure. There was significant resolution of the vasospasm. The long-term clinical outcome in one patient was
excellent, the other still has minor deficits. Combined endovascular aneurysm therapy followed by intra-arterial spasmolysis
with papaverine is a technically feasable therapeutic alternative in patients with symptomatic vasospasm.
Received: 5 November 1999/Accepted: 12 July 2000 相似文献
77.
Silke Kauferstein Isabelle Huys Hung Lamthanh Reto St?cklin Filipina Sotto André Menez Jan Tytgat Dietrich Mebs 《Toxicon》2003,42(1):43-52
Toxins from cone snail (Conus species) venoms are multiple disulfide bonded peptides. Based on their pharmacological target (ion channels, receptors) and their disulfide pattern, they have been classified into several toxin families and superfamilies. Here, we report a new conotoxin, which is the first member of a structurally new superfamily of Conus peptides and the first conotoxin affecting vertebrate K+ channels. The new toxin, designated conotoxin ViTx, has been isolated from the venom of Conus virgo and comprises a single chain of 35 amino acids cross-linked by four disulfide bridges. Its amino acid sequence (SRCFPPGIYCTSYLPCCWGICCSTCRNVCHLRIGK) was partially determined by Edman degradation and deduced from the nucleotide sequence of the toxin cDNA. Nucleic acid sequencing also revealed a prepropeptide comprising 67 amino acid residues and demonstrated a posttranslational modification of the protein by releasing a six-residue peptide from the C-terminal. Voltage clamp studies on various ion channels indicated that the toxin inhibits the vertebrate K+ channels Kv1.1 and Kv1.3 but not Kv1.2. The chemically synthesized product exhibited the same physiological activity and identical molecular mass (3933.7 Da) as the native toxin. 相似文献
78.
Masahito Katoh Rick Wilmotte Marie-Claude Belkouch Nicolas de Tribolet Gianpaolo Pizzolato Pierre-Yves Dietrich 《Journal of neuro-oncology》2003,64(1):71-76
Survivin, a member of the inhibitor of apoptosis proteins gene family, was recently shown to be expressed by tumors originating from different cell lineages. There are also cumulative evidences that spontaneous immune response against survivin derived epitopes may occur. Here, using RT-PCR, Western-blot analysis and immunohistochemistry, we show that survivin is widely expressed by gliomas, meningiomas and schwannomas, both in vitro and in vivo. These data indicate that survivin may serve as an attractive target for immunotherapies designed for brain tumors. 相似文献
79.
Posttraumatic hypothermia reduces polymorphonuclear leukocyte accumulation following spinal cord injury in rats 总被引:6,自引:0,他引:6
Chatzipanteli K Yanagawa Y Marcillo AE Kraydieh S Yezierski RP Dietrich WD 《Journal of neurotrauma》2000,17(4):321-332
The present study addresses the effects of moderate posttraumatic hypothermia (32 degrees C) on the temporal and regional profile of polymorphonuclear leukocyte (PMNL) accumulation after traumatic spinal cord injury (SCI). We hypothesized that posttraumatic hypothermia would reduce the degree of inflammation by reducing PMNL infiltration. Rats underwent moderate spinal cord injury at T10 using the NYU impactor device. In the first study, the temporal profile of myeloperoxidase (MPO) activity (a marker of neutrophil accumulation) under normothermic (37 degrees C) conditions was determined. The animals were allowed to survive for 3 or 24 h, or 3 or 7 days after SCI. Spinal cords were dissected into five segments rostral and caudal to the injury site. Additional animals were studied for the immunocytochemical visualization of MPO. In the second study, rats were sacrificed at 24 h after a monitoring period of normothermia (36.5 degrees C/3 h) or hypothermia (32.4 degrees C/3 h) with their controls. In the time course studies, MPO enzymatic activity was significantly increased at 3 and 24 h within the traumatized T10 segment compared to controls. MPO activity was also increased at 3 h within the rostral T8 and T9 segments and caudal T11 and T12 segments compared to controls. At 24 h after trauma, MPO activity remained elevated within both the rostral and caudal segments compared to control. By 3 days, the levels of MPO activity were reduced compared to the 24-h values but remained significantly different from control. Neutrophils that exhibited MPO immunoreactivity were seen at 6 and 24 h, with a higher number at 3 days. PMNLs were located within the white and gray matter of the lesion and both rostral and caudal to the injury site. Posttraumatic hypothermia reduced MPO activity at 24 h in the injured spinal cord segment, compared to normothermic values. The results of this study indicate that a potential mechanism by which hypothermia improves outcome following SCI is by attenuating posttraumatic inflammation. 相似文献
80.
Bruce JH Norenberg MD Kraydieh S Puckett W Marcillo A Dietrich D 《Journal of neurotrauma》2000,17(9):781-788
Schwannosis (aberrant proliferation of Schwann cells and nerve fibers) has been reported following spinal cord injury (SCI). In this study, we examined the incidence of schwannosis following human SCI, and investigated its relationship to gliosis. We found evidence of schwannosis in 32 out of 65 cases (48%) of human SCI that survived 24 h to 24 years after injury; this incidence rose to 82% in those patients who survived for more than 4 months. Schwannosis was not observed in cases that survived less than 4 months after injury. In affected cases, it was generally noted in areas that had low immunoreactivity for glial fibrillary acidic protein (GFAP), suggesting that reduced gliosis might have contributed to the aberrant proliferation of Schwann cells following SCI. Since chondroitin sulfate proteoglycan (CSPG) has been proposed to play a role in Schwann cell/glial interaction, we performed immunohistochemical staining for CSPG to investigate its potential relationship with schwannosis. CSPG in the injured cord was generally associated with the blood vessel walls, but was also sometimes noted in reactive astrocytes. In SCI with schwannosis, CSPG staining was more prominent and confined largely to the extracellular matrix and basal lamina of proliferating Schwann cells. Our study suggests that Schwann cells, which may have been displaced from spinal roots and introduced into the injured cord through a break in the pial surface, are capable of proliferating and producing CSPG, particularly in the setting of reduced gliosis. Since CSPG has been associated with inhibition of neurite outgrowth, its increased production by aberrant Schwann cells may impair spinal cord regeneration after injury. 相似文献