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921.
立体适形放射治疗前列腺癌29例临床分析 总被引:1,自引:0,他引:1
目的:分析立体适形放射治疗(3D-CRT)前列腺癌的疗效.方法:采用3D-CRT治疗前列腺癌29例,26例放疗前行双侧睾丸切除,22例同时服用内分泌治疗药物.采用3D-CRT技术,5次/周,1.8~2Gy/次,DT 60~72Gy,中位剂量68Gy.结果:中位随访18个月,生存率82.8%,肿瘤特异生存率93.1%.1、2、3级急性胃肠道不良反应发生率分别为44.8%,6.9%,3.4%,1、2级急性泌尿生殖系统不良反应发生率分别为34.5%,6.9%.结论:3D-CRT治疗前列腺癌疗效满意,不良反应小. 相似文献
922.
923.
目的 :研究放疗结合超声热疗治疗恶性肿瘤的疗效及毒副反应。方法 :1997年 1月~ 2 0 0 0年 1月间4 1例经病理证实的局部晚期、复发 /转移或对放射敏感性差的表浅性恶性肿瘤患者接受放疗加超声热疗 ,放疗均采用外照射 ,平均剂量 (6 1± 12 )Gy ,热疗于放疗结束后 30分钟内进行 ,1~ 2次 /周 ,平均加热时间为 (5 2 .4± 6 )分钟 ,平均加热 (4.9± 2 .2 )次。采用方差分析肿瘤消退率与热疗参数的关系 ;Kaplan Meier、Cox回归分析三年局部控制率、生存率和预后因素的影响。结果 :CR、PR、NC间的Tmin、Tmax值差异具有统计学意义。全组肿瘤局部CR为 5 8.5 % ,三年局控率、生存率分别为 13.6 %和 32 .6 9%。Tmin、肿瘤体积、放射剂量对三年局控率有显著性影响 (P <0 .0 5 )。超声热疗配合放疗毒副反应较轻。结论 :Tave、Tmax、Tmin、Tmax等参数可用于反映、评价热疗效果 ,放疗结合超声热疗为治疗晚期表浅性恶性肿瘤的有效方法 ,毒性小 ,值得进一步研究。 相似文献
924.
目的 研究CT、MRI、PET在肺部球形病灶中的综合诊断价值。方法 回顾性分析 6 5例有CT、MRI、PET资料并经病理证实的肺部球形病灶。结果 分析CT、MRI及PET三者敏感性、特异性、准确性、阳性预测值和阴性预测值 ,并进行比较 ,发现其敏感性和特异性均无显著性差异 (P值分别为0 .377和 0 .7)。通过CT、MRI、PET的互补 ,在 4 4例肺癌中 ,仅 1例误诊 ,2 1例良性病变中 ,诊断正确的有 19例 ,其敏感性、特异性、准确性、阳性预测值和阴性预测值分别为 97.7%、90 .5 %、95 .4 %、95 .6 %和95 %。结论 多种手段的综合利用 ,有助于提高肺部球形病灶的诊断正确率。 相似文献
925.
Kathleen M Egan Qiuyin Cai Xiao-Ou Shu Fan Jin Tian-Li Zhu Qi Dai Yu-Tang Gao Wei Zheng 《Cancer epidemiology, biomarkers & prevention》2004,13(2):197-204
PURPOSE: We studied the relation of breast cancer to common deletion mutations in GSTM1 and GSTT1 and the functional Ile(105)Val polymorphism in GSTP1 in a large, population-based case-control study conducted in China and performed a meta-analysis to summarize the literature. EXPERIMENTAL DESIGN: In the case-control study, a total of 1144 breast cancer cases and 1221 community controls were genotyped for GSTM1, GSTP1, and GSTT1 using PCR-based methods. Associations of genotypes and breast cancer were evaluated in logistic regression models. Meta-analysis odds ratios (ORs) were estimated using a fixed effects model. RESULTS: In the case-control study, associations were null for GSTM1 [age-adjusted OR 0.97, 95% confidence interval (CI): 0.82-1.14] and GSTT1 (OR 0.97, 95% CI: 0.83-1.15). A significant increase in risk was observed among homozygotes for the variant Ile(105)Val polymorphism (OR 1.92, 95% CI: 1.21-3.04). No combined effects of GSTM1, GSTP1, and GSTT1 genotypes or interactions with potential effect modifiers were detected. All results were similar in pre- and postmenopausal women and for early versus advanced stage breast cancer. The meta-analysis, based predominantly on Caucasian women, supported null results for the homozygous deletion variant in GSTM1 (summary OR 1.05; combining 19 studies) and GSTT1 (summary OR 1.11; 15 studies). Meta-analysis results for the homozygous GSTP1 variant indicated no overall association (summary OR 1.04; 10 studies), although results varied significantly across studies (P = 0.009). CONCLUSIONS: This large case-control study provides strong support for earlier studies showing no overall association of the GSTM1 and GSTT1 deletion polymorphisms with breast cancer risk. The GSTP1 variant may be relevant to breast cancer risk in Asian populations. 相似文献
926.
927.
Ability of a Specific ERK Signal-Pathway Inhibitor to Reverse P-Glycoprotein- Mediated Vincristine Resistance in Colon Cancer Cell Unes 总被引:1,自引:0,他引:1
FengJin HuaFan BoChen PingLu FanYao HuimianXu ShubaoWang 《中国肿瘤临床(英文版)》2004,1(4):295-300
OBJECTIVE To investigate the effect of a specific inhibitor PD098059 of the extracellular-signal regulated protein kinase (ERK) pathway on the P-glycoprotein (P-gp)-mediated resistance of colon cancer cell lines SW480/VCR and CoLo205NCR.METHODS SW480NCR and CoLo205NCR cells were generated byexposuring SW480 and CoLo205 cells to vincristine (VCR) (30 ng/ml) for 72h, which resulted in a comparatively higher level of P-gp expression.Western blotting was used to analyze P-gp, MRP, LRP, GST-‘rr and TOPOIIexpression after exposuring the SW480 and CoLo205 cells to VCR (30 ng/ml)for 72 hrs. P-gp and pERK1/2 expressions was analyzed in SW480NCR andCoLo205/VCR cells treated with or without the specific inhibitor of MEK,PD098059. The MTT assay was used to determine the susceptibility ofSW480NCR and CoLo205NCR cells to VCR, treated with or withoutPD098059.I~F.SULI“S The results showed that VCR induced a comparatively higher levelof P-gp expression in the cell lines, but not that of MRP, LRP, GST-n- orTOPOII. P-gp expression levels were depressed significantly in SW480/VCR and COLO205/VCR cells by the specific inhibitor of MEK, PD098059.The IC50 (248 19.6 and 215 10.7 ng/ml) to VCR of SW480/VCR andCoLo205/VCR cells exhibited a 2.16 and 2.03-fold higher resistancecompared to the negative control group (SW480 and CoLo205 cells)(115 15.6 and 106 11.9 ng/ml), but a 1.35 and 1.21 -fold higher resistance thanthe group treated with VCR (30 ng/ml) PD098059 (184 21.8 and 177 19.4 ng/ml).CONCLUSION This study shows that the expression of P-gp can beinduced by exposuring cells to VCR, and that this induction can be reversedby inhibiting the ERK signaling pathway at the point of MEK by its specificinhibitor, PD098059. The ERK signal-transduction pathway may play a rolein modulating mdrl expression in colon cancer. 相似文献
928.
Major histocompatibility complex class I peptide-pulsed host dendritic cells induce antigen-specific acquired thymic tolerance to islet cells 总被引:7,自引:0,他引:7
BACKGROUND: As T-cell receptor-major histocompatibility complex (MHC) class I/self peptide interaction regulates T-cell development in the thymus, we reasoned that presentation of peptides by self dendritic cells (DC) to developing T cells in the thymus might induce acquired thymic tolerance. This hypothesis is based on the finding that intrathymic injection of allopeptides in the adult animal induces acquired tolerance. To examine this hypothesis, we studied the effects of intrathymic (IT) injection of a single immunodominant Wistar-Furth (WF) MHC class I (RT1.Au) peptide-pulsed host DC on islet allograft survival in the WF-to-ACI rat combination. METHODS: Bone marrow-derived ACI DC expressing MHC class I and II, OX62, and ED2 present allopeptides to naive and specifically peptide-primed syngeneic T cells in mixed lymphocyte reaction. Host DC pulsed with RT1.Au peptide 5 (residues 93-109) were injected into the thymus of streptozotocin-induced diabetic ACI that were transplanted 7 days later with donor-type (WF) or third-party (Brown Norway [BN]) islets. RESULTS: Whereas IT injection of 300 microg of peptide 5 alone led to normoglycemia and permanent islet survival in three of six diabetic ACI recipients, similar treatment combined with simultaneous intraperitoneal injection of 0.5 ml of anti-lymphocyte serum (ALS) on day -7 led to 100% permanent islet allograft survival (>200 days) compared to a mean survival time of 15.0+/-2.3 days in controls treated with ALS alone. In contrast, similarly prepared animals rejected the third-party (BN) islets in an acute fashion. To address the question of indirect allorecognition in acquired thymic tolerance, we examined the effect of peptide-pulsed host DC on graft survival. Whereas IT injection of peptide-pulsed host DC alone resulted in permanent islet survival in two of five animals, IT injection of peptide-pulsed host DC combined with 0.5 ml of ALS induced 100% donor-specific permanent islet allograft survival in the WF-to-ACI rat combination. These results suggest that thymic DC take up, process, and present the administered peptide to the developing T cells by the indirect allorecognition pathway in the induction of acquired thymic tolerance. CONCLUSION: We have demonstrated a novel approach to inducing transplant tolerance to islet allografts with IT injection of allopeptide-pulsed host DC. This finding suggests that immunization strategies using DC expressing MHC allopeptides or peptide analogue might be potentially useful in the treatment of autoimmune diabetes mellitus. 相似文献
929.
bFGF调节PDGF对人成骨细胞的促增殖作用 总被引:6,自引:0,他引:6
目的 探讨碱性成纤维细胞生长因子(bFGF)对血小板衍生生长因子(PDGF)促成骨细胞增殖作用的影响及其机制。方法 分离培养人成骨细胞;以PDGF-AB(100ng/ml)单独培养、bFGF(10ng/ml)与PDGF-AB(100ng/ml)混合培养、不加生长因子等3种方式培养细胞,绘制细胞生长曲线;bFGF(10ng/ml)与PDGF-AA或PDGF-BB(浓度均为40ng/ml)以不同方式联 相似文献
930.
Genetic polymorphisms in the estrogen receptor alpha gene and risk of breast cancer: results from the Shanghai Breast Cancer Study. 总被引:11,自引:0,他引:11