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131.
We investigated ADAMTS13 activity as well as the ADAMTS13 gene mutation in children with hemolytic uremic syndrome (HUS). Eighteen patients, including 6 diarrhea- negative (D-HUS) and 12 diarrhea-associated HUS (D+HUS) patients, were evaluated. The extent of von Willebrand factor (VWF) degradation was assayed by multimer analysis, and all exons of the ADAMTS13 gene were PCR-amplified using Taq DNA polymerase. The median and range for plasma activity of ADAMTS13 in 6 D-HUS and 12 D+HUS patients were 71.8% (22.8-94.1%) and 84.9% (37.9-119.9%), respectively, which were not statistically significantly different from the control group (86.4%, 34.2-112.3%) (p>0.05). Five ADAMTS13 gene mutations, including 2 novel mutations [1584+2T>A, 3941C>T (S1314L)] and 3 polymorphisms (Q448E, P475S, S903L), were found in 2 D-HUS and one D+HUS patients, which were not associated with deficiency of ADAMTS13 activity. Whether these mutations without reduced ADAMTS13 activity are innocent bystanders or predisposing factors in HUS remains unanswered. 相似文献
132.
Purpose
To investigate the effect of bevacizumab (Avastin; Genentech, San Francisco, CA, USA) on vascular endothelial growth factor (VEGF) expression and inflammation in fibrovascular membranes in patients with proliferative diabetic retinopathy (PDR).Materials and Methods
Fibrovascular membranes from 19 eyes of 18 patients with PDR were studied using immunohistochemistry and analyzed in the following 3 groups; group 1: 4 inactive PDR eyes, group 2: 10 active PDR eyes treated preoperatively with adjunctive intravitreal bevacizumab, group 3: five active PDR eyes not treated preoperatively with bevacizumab. Immunohistochemical staining for VEGF, CD31 and CD68 were done.Results
The immunoreactivity to VEGF and CD 31-positive blood vessels was significantly higher in membranes from group 3 than group 1 (p = 0.007 for VEGF, 0.013 for CD 31-positive vessels). Intravitreal bevacizumab caused a reduction in VEGF expression and vascular densities in 4 out of 10 (40%) excised membranes from eyes with PDR. However, six membranes (60%) in group 2 still demonstrated relatively strong VEGF expression and high vascular density. Infiltration of macrophages was observed in 16 out of the 19 membranes, and the density of macrophages was increased in group 2 compared with group 1 (p = 0.043).Conclusion
Intravitreal bevacizumab injections caused some reduction in VEGF expression and vascular densities in a limited number of active PDR patients. A single intravitreal bevacizumab injection may not be enough to induce complete blockage of VEGF and pathologic neovascularization in active PDR patients. Repeated injections, panretinal photocoagulation and/or PPV may be necessary following intravitreal bevacizumab to reinforce the anti-VEGF effect of the drug. 相似文献133.
Taek Rim Yoon Kyung Soon Park Eun Kyoo Song Jong Keun Seon Hyoung Yeon Seo 《Journal of orthopaedic science》2009,14(2):155-160
Background There has been increasing interest in performing total hip arthroplasty (THA) with minimally invasive surgery (MIS). This
study was conducted to examine the effectiveness of MIS-THA using the new two-incision technique versus the one-incision technique.
Methods A consecutive series of 113 patients who underwent MIS-THAs (63 one-incision cases, 50 two-incision cases) were studied. One-incision
THA was performed with a posterolateral approach. For the two-incision, the first incision for cup insertion was made over
the anterolateral side of the hip. Intermuscular dissection was performed between the gluteus medius and the tensor fascia
lata. The second incision, for stem insertion, was made on the posterolateral side of the hip along the fiber of the gluteus
maximus. Intermuscular dissection was made between the gluteus medius and the piriformis.
Results Postoperative rehabilitation was significantly more rapid in the new two-incision group compared to the group with one incision.
Postoperatively, the Harris Hip Score and the Western Ontario and the McMaster Universities Osteoarthritis Index score were
significantly different between the two groups, especially the functional sections.
Conclusions The findings of this study show that our new two-incision MIS-THA is an excellent surgical modality that allows early rehabilitation. 相似文献
134.
Shin KY Won BY Heo C Kim HJ Jang DP Park CH Kim S Kim HS Kim YB Lee HG Lee SH Cho ZH Suh YH 《Journal of neuroscience research》2009,87(1):260-268
In Oriental medicine, roots of Polygala tenuifolia Willdenow have been known to be an important herb that exhibits sedative effects in insomnia, palpitation with anxiety, restlessness, and disorientation in humans. We previously reported that BT-11, extracted from those roots, improved scopolamine-induced amnesia in rats and inhibited acetylcholinesterase activities in vitro. Therefore, we proposed that BT-11 could remedy stress-induced memory deficits in rats. In this study, the stress-induced memory impairments in rats were significantly reversed almost to the control level by BT-11 treatment. To seek an active component of BT-11 that plays an important role in antipsychotic effects, we compared BT-11 with 3,4,5-trimethoxycinnamic acid (TMCA), which is a constituent of those root extracts. However, the effects of TMCA were less or were not consistent with those of BT-11 in some of tests. In particular, BT-11 reversed the stress-induced reduction of glucose utilization by [(18)fluorodeoxyglucose]FDG-PET and the levels of neural cell adhesion molecule (NCAM) in rat brains to the control levels, whereas TMCA did not. Therefore, BT-11 improved stress-induced memory impairments through increment of glucose utilization and total NCAM levels in rat brains. In conclusion, BT-11 may be strongly effective against stress-induced amnesia in rats, through the combined effects of TMCA and other active components of BT-11. 相似文献
135.
Hyoung Chul Choi Kwang Youn Lee Dong Hyup Lee Young Jin Kang 《The Korean journal of physiology & pharmacology》2009,13(4):309-313
Spontaneous hypertensive rats (SHR) are an established model of genetic hypertension. Vascular smooth muscle cells (VSMC) from SHR proliferate faster than those of control rats (Wistar-Kyoto rats; WKY). We tested the hypothesis that induction of heme oxygenase (HO)-1 induced by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats. Aprotinin treatment inhibited VSMC proliferation in SHR more than in normotensive rats. These inhibitory effects were associated with cell cycle arrest in the G1 phase. Tin protoporphyrin IX (SnPPIX) reversed the anti-proliferative effect of aprotinin in VSMC from SHR. The level of cyclin D was higher in VSMC of SHR than those of WKY. Aprotinin treatment downregulated the cell cycle regulator, cyclin D, but upregulated the cyclin-dependent kinase inhibitor, p21, in VSMC of SHR. Aprotinin induced HO-1 in VSMC of SHR, but not in those of control rats. Furthermore, aprotinin-induced HO-1 inhibited VSMC proliferation of SHR. Consistently, VSMC proliferation in SHR was significantly inhibited by transfection with the HO-1 gene. These results indicate that induction of HO-1 by aprotinin inhibits VSMC proliferation through cell cycle arrest in hypertensive rats. 相似文献
136.
Molecular determinants for the interaction between AMPA receptors and the clathrin adaptor complex AP-2 总被引:1,自引:0,他引:1
Kastning K Kukhtina V Kittler JT Chen G Pechstein A Enders S Lee SH Sheng M Yan Z Haucke V 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(8):2991-2996
alpha-Amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-type glutamate receptors undergo constitutive and ligand-induced internalization that requires dynamin and the clathrin adaptor complex AP-2. We report here that an atypical basic motif within the cytoplasmic tails of AMPA-type glutamate receptors directly associates with mu2-adaptin by a mechanism similar to the recognition of the presynaptic vesicle protein synaptotagmin 1 by AP-2. A synaptotagmin 1-derived AP-2 binding peptide competes the interaction of the AMPA receptor subunit GluR2 with AP-2mu and increases the number of surface active glutamate receptors in living neurons. Moreover, fusion of the GluR2-derived tail peptide with a synaptotagmin 1 truncation mutant restores clathrin/AP-2-dependent internalization of the chimeric reporter protein. These data suggest that common mechanisms regulate AP-2-dependent internalization of pre- and postsynaptic membrane proteins. 相似文献
137.
138.
Introduction Transient global amnesia (TGA) is characterized by a sudden onset of anterograde amnesia without alteration of consciousness
or personal identity. Interestingly, recent studies have reported a high frequency of small high-signal abnormalities in the
hippocampus with diffusion-weighted (DW) imaging, and ischemia has been proposed as an etiology of TGA. We hypothesized that
TGA lesions occur preferentially in the CA1 region of the hippocampus, known to be susceptible to ischemia.
Methods Over a 30-month period 34 patients with TGA underwent MRI including DW imaging within 4 days of symptom onset. Patients with
high-signal abnormalities in the hippocampus on the initial DW images underwent subsequent DW and T2-weighted imaging in the
coronal plane to identify the precise lesion locations.
Results Fourteen patients had small (1–3 mm) high-signal abnormalities in the hippocampus unilaterally on DW images. One of these
patients had two lesions in one hippocampus and therefore in total 15 lesions were identified: four in the hippocampal head,
and 11 in the body. Eleven lesions in ten patients with available coronal images were clearly demonstrated on both coronal
DW and T2-weighted images and were localized to the lateral portion of the hippocampus, corresponding to the CA1 region.
Conclusion Lesions associated with TGA were localized exclusively to the lateral portion of the hippocampus corresponding to the CA1
region. This finding supports the ischemic etiology of TGA; however, the pathophysiological mechanism involved requires further
study. 相似文献
139.
140.
Seongwon Cha Imhoi Koo Sun Mi Choi Byung Lae Park Kil Soo Kim Jae-Ryong Kim Hyoung Doo Shin Jong Yeol Kim 《BMC medical genetics》2009,10(1):96