全文获取类型
收费全文 | 1552篇 |
免费 | 110篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 31篇 |
妇产科学 | 22篇 |
基础医学 | 256篇 |
口腔科学 | 36篇 |
临床医学 | 88篇 |
内科学 | 391篇 |
皮肤病学 | 43篇 |
神经病学 | 145篇 |
特种医学 | 38篇 |
外科学 | 202篇 |
综合类 | 6篇 |
预防医学 | 70篇 |
眼科学 | 49篇 |
药学 | 117篇 |
中国医学 | 10篇 |
肿瘤学 | 143篇 |
出版年
2024年 | 1篇 |
2023年 | 20篇 |
2022年 | 46篇 |
2021年 | 89篇 |
2020年 | 49篇 |
2019年 | 52篇 |
2018年 | 58篇 |
2017年 | 45篇 |
2016年 | 52篇 |
2015年 | 43篇 |
2014年 | 64篇 |
2013年 | 82篇 |
2012年 | 148篇 |
2011年 | 128篇 |
2010年 | 83篇 |
2009年 | 39篇 |
2008年 | 112篇 |
2007年 | 74篇 |
2006年 | 92篇 |
2005年 | 97篇 |
2004年 | 83篇 |
2003年 | 69篇 |
2002年 | 69篇 |
2001年 | 12篇 |
2000年 | 12篇 |
1999年 | 4篇 |
1998年 | 8篇 |
1997年 | 8篇 |
1996年 | 8篇 |
1995年 | 5篇 |
1994年 | 1篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1990年 | 4篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有1674条查询结果,搜索用时 140 毫秒
101.
102.
103.
A 58-year-old man was scheduled for laryngomicrosurgery for treatment of large laryngeal polyps. Although awake induction was initially attempted to prevent airway obstruction, his vocal cords could not be visualized. We therefore tried intubation with a Parker Flex-Tip (PFT) tube under the guidance of a bronchial fiberscope (BF). After inserting the BF, his trachea was intubated easily. The operation was performed without any complications. We conclude that a PFT tube is useful for endotracheal intubation in a patient with large laryngeal polyps. 相似文献
104.
Dendritic cells, T-cell infiltration, and Grp94 expression in cholangiocellular carcinoma 总被引:4,自引:0,他引:4
Takagi S Miyagawa S Ichikawa E Soeda J Miwa S Miyagawa Y Iijima S Noike T Kobayashi A Kawasaki S 《Human pathology》2004,35(7):881-886
Although dendritic cells (DCs) play an important role in tumor immunity, there have been no reports on their role in cholangiocellular carcinoma (CCC). In 26 formalin-fixed, paraffin-embedded tissue sections from patients with CCC, cells positive for CD83 (a marker of mature DCs), CD1a (a marker of immature DCs), and CD8 and CD4 (T cell markers) were counted, and expression of glucose-regulated protein (grp) 94, which is considered to participate in the maturation of DCs, was evaluated by immunohistochemistry and Western blot analysis to study the relationship between their expression and patients' disease outcome. The number of CD83-positive DCs at the invasive margin of CCCs correlated significantly with the number of CD8-positive or CD4-positive T cells in the cancerous region and was significantly higher in grp94-positive cancer than in grp94-negative cancer (P = 0.0006). CD83-positive patients (positive cells in invasive margin > 12.4/field) had both a significantly lower incidence of lymph node metastasis (23.1% vs 69.2%; P = 0.0206) and a better outcome than CD83-negative patients (P <0.001). We conclude that mature DCs are distributed predominantly at the invasive margin of cancers, and a significantly higher number of mature DCs at the invasive margin are observed in patients with grp94-positive cancer cells. Mature DCs may enhance CD8- and CD4-positive cell infiltration into cancers and improve prognosis in patients with CCC, due in part to abatement of lymph node metastasis. 相似文献
105.
The aim of the current study was to measure the concentrations of erythropoietin in the vitreous fluid and analyze its association with vascular endothelial growth factor (VEGF) in ischemic vitreoretinal diseases. Vitreous fluid samples were collected from patients with proliferative diabetic retinopathy, branch retinal vein occlusion and idiopathic macular hole. Concentrations of erythropoietin and VEGF in vitreous fluid were significantly elevated in patients with proliferative diabetic retinopathy and branch retinal vein occlusion as compared to patients with macular hole. There were no differences in serum concentrations of erythropoietin and VEGF among patient groups. There was significant correlation between erythropoietin and VEGF concentrations in vitreous fluid. Erythropoietin was up-regulated in ischemic disorders and may act as an endogenous neuroprotective factor against ischemic retinal disorders. 相似文献
106.
Taura K Naito E Ishii Y Mori MA Oguri K Yamada H 《Biological & pharmaceutical bulletin》2004,27(1):56-60
The effects of cytochrome P450 (P450, CYP) ligands and permeabilization of microsomes on 3-hydroxybenzo(a)pyrene [3-OH-B(a)P] glucuronidation mediated by rat hepatic microsomes were studied. While the UDP-glucuronosyltransferase (UGT) activity with non-permeabilized microsomes from 3-methylcholanthrene (MC)-treated rats was markedly reduced by alpha-naphthoflavone (NF), this inhibitor had hardly any effect when permeabilized microsomes were used in which the inhibitor was expected to have easy access to UGT. Kinetic analysis indicated that the inhibitory effect of alpha-NF is competitive. These results suggest that a UGT isoform(s) involved in 3-OH-B(a)P glucuronidation is interfered by a CYP1A inhibitor via a mechanism dependent on the intact nature of microsomal membranes in MC-treated rats. It is likely that P450 functions as a substrate transporter for some isoforms of UGT via possible interactions between UGT and P450. 相似文献
107.
108.
Tanida S Shimoma E Mashima R Ma L Yamagishi T 《Shinrigaku kenkyu : The Japanese journal of psychology》2003,74(2):148-155
Results of three experiments, in which a total of 167 students participated, consistently indicated that participants performed recognition tasks better for face photographs of defectors than those of cooperators. The face photographs used in the experiments were those of participants taken during prisoner's dilemma (PD) experiments a few years prior to the present study. In Experiments 1 and 2, photographs of cooperators and defectors in a one-shot PD experiment, taken after they had filled out a lengthy post-experimental questionnaire, were used. In Experiment 3, the photographs were those of high and low cooperators, taken at the moment of a cooperation or defection choice, respectively. Recognition was better for photographs that were judged unattractive than attractive. At the same time, it was better for photographs of less cooperative participants in the PD studies than those of more cooperative participants. Implications of the findings for Cosmides & Tooby's (1992) 'cheater-detection' module for social exchange domain were discussed. 相似文献
109.
Delivery outcomes following loop electrosurgical excision procedure for microinvasive (FIGO stage IA1) cervical cancer 总被引:10,自引:0,他引:10
Paraskevaidis E Koliopoulos G Lolis E Papanikou E Malamou-Mitsi V Agnantis NJ 《Gynecologic oncology》2002,86(1):10-13
OBJECTIVE: The goal of this study was to report the delivery outcomes in women who had loop electrosurgical excision procedure (LEEP) for microinvasive cervical cancer (stage IA1 without lymphovascular invasion) and became pregnant and progressed beyond 24 weeks. METHODS: A case-control study was performed. Twenty-eight women who were managed exclusively with LEEP for microinvasive cervical carcinoma had at least one pregnancy beyond 24 weeks and were the cases. Each case was matched with one woman who delivered at the same department without prior treatment of her cervix (controls) and their delivery outcomes were compared with those of the cases. Known risk factors for preterm delivery were used as matching factors. RESULTS: There was no statistically significant difference (P > 0.05) between cases and controls in the duration of pregnancy (37.6-38.4 weeks respectively), birth weight (3212-3315 g), cesarean section rate (17.8-32.1%), neonatal unit admission rate (21.4-10.7%), and precipitate labor rate (13-10.5%). The duration of labor was significantly shorter in cases (5.5-7.1 h, P = 0.032). After LEEP the relative risk for preterm delivery is 3.67 (95% confidence interval, 0.97-20.27), for low birth weight infant 0.67 (0.06-5.8), for precipitate labor 1 (0.05-3.88), and for delivery by cesarean section 0.5 (0.17-4.46). CONCLUSIONS: Women treated for microinvasive cancer with LEEP did not have significantly more delivery complications compared with controls apart from shorter duration of labor. There was a possible non-statistically significant trend toward shorter duration of pregnancy in cases. While caution should be advised when selecting and treating women with microinvasive carcinoma by LEEP, the apparent safety of the management and the satisfactory delivery outcome seem to justify this approach in many cases. 相似文献
110.
Cyclin D1 amplification and p16(MTS1/CDK4I) deletion correlate with poor prognosis in head and neck tumors 总被引:12,自引:0,他引:12
Namazie A Alavi S Olopade OI Pauletti G Aghamohammadi N Aghamohammadi M Gornbein JA Calcaterra TC Slamon DJ Wang MB Srivatsan ES 《The Laryngoscope》2002,112(3):472-481
OBJECTIVES/HYPOTHESIS: Cyclin D1, a cell cycle regulator localized to chromosome 11q13, is amplified in several human tumors including head and neck squamous cell carcinoma (HNSCC). Amplification and/or overexpression of cyclin D1 have been correlated to a poor prognosis. Deletion of the p16 gene, localized to 9p21, has also been observed in a significant proportion of HNSCC. The p16 gene regulates cyclin D1-CDK4 activity and prevents retinoblastoma tumor suppressor gene phosphorylation, thereby downregulating cellular proliferation. Detection of cyclin D1 amplification and p16 deletion using a simple and sensitive method will be valuable for the development of effective treatment modalities for head and neck cancer. STUDY DESIGN: We have used fluorescence in situ hybridization (FISH) to study cyclin D1 amplification and p16 gene deletion in head and neck tumors. Both single- and dual-color FISH were performed. METHODS: Paraffin-embedded tissues from 103 patients with HNSCC were analyzed using genomic DNA probes for cyclin D1 and p16. Dual-color FISH was performed with chromosome 11 or 9 centromeric probes as a control. Twenty-eight of these samples were analyzed for p16 expression by immunohistochemistry. RESULTS: Cyclin D1 amplification was observed in 30% (31/103) of patients, and p16 deletion in 52% (54/103). Lack of p16 expression was observed in 64% (18/28) of patients. There was a good correlation between the deletion of p16 sequences and the loss of p16 expression (P = .008). Amplification of cyclin D1 had a statistically significant association with recurrence, distant metastasis, and survival at 36 months. There was a significant association between p16 deletion and the development of distant metastases. Cyclin D1 amplification and p16 deletion together correlated with recurrence, distant metastasis, and survival. CONCLUSIONS: We demonstrate that FISH is a simple and sensitive method for detecting cyclin D1 amplification and p16 deletion in head and neck cancer. Our results suggest that these two genetic aberrations together portend a poorer outcome than either of the abnormalities alone in head and neck cancer. 相似文献