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61.
62.

Background  

Neuromyelitis optica spectrum disorders (NMOSD) are severe central nervous system inflammatory demyelinating disorders (CNS IDD) characterized by monophasic or relapsing, longitudinally extensive transverse myelitis (LETM) and/or optic neuritis (ON). A significant proportion of NMOSD patients are seropositive for aquaporin-4 (AQP4) autoantibodies. We compared the AQP4 autoantibody detection rates of tissue-based indirect immunofluorescence assay (IIFA) and cell-based IIFA.  相似文献   
63.
AIM: To study the effects of Tetramethylpyrazine (TMP) on retinal pigment epithelium (RPE) degeneration, choroidal blood flow and oxidative stress of RPE cells. METHODS: The 35mg/kg NaIO3-induced RPE degeneration rat eyes was given 25μg 1% TMP eye drops 3 times a day for 7 days before NaIO3 injection, and then 2 to 4 weeks after NaIO3 injection. RPE function was measured with c-wave of electroretinogram (ERG). Colored microsphere technique was used for in vivo experiments to determine the choroidal blood flow in ocular hypertensive (40mmHg) rabbit eyes. Methylthiazoltetrazolium (MTT) assay was used to study in vitro effect of TMP on various oxidants induced injury in the hRPE (ARPE-19 (ATCC, Manassas, VA, USA)) . RESULTS: Two weeks after NaIO3 injection, the amplitude of ERG c-wave fell markedly in NaIO3 group to 36% of control group(P <0.01). No apparent difference was observed in TMP+NaIO3 group. Four weeks later, the NaIO3 group fell to 46% of control group (P<0.01), while the TMP+NaIO3 group fell to only 77% of control group (P<0.01). There was a 67% reversal of the ERG c-wave by TMP as compared to NaIO3 group(P<0.01). The choroidal blood flow was significantly increased at all time points (at 30, 60 and 120 minutes after TMP instillation) as compared with corresponding controls. TMP had no effect on hypoxia-(1%O2), t-BHP- and H2O2-induced damage in RPE cells. 10(g/mL TMP could reverse 1 and 3mM NaN3-induced loss of viability of RPE by 18.5% (P <0.01) and 23% (P<0.01), respectively. 30μg/mL TMP could reverse 30 and 100mM NaIO3 induced loss of viability of RPE by 18.1% (P <0.05) and 16.8% (P <0.01), respectively. CONCLUSION: TMP can significantly protect RPE from NaIO3 induced degeneration in vivo and oxidative stress in vitro and can increase choroidal blood flow markedly in vivo.  相似文献   
64.
AIM: To analyze whether pancreaticoduodenectomy with simultaneous resection of tumor-involved vessels is a safe approach with acceptable patient survival.METHODS: Between January 2001 and March 2012, 136 patients received pancreaticoduodenectomy for adenocarcinoma at our hospital. Seventy-eight patients diagnosed with pancreatic head carcinoma were included in this study. Among them, 46 patients received standard pancreaticoduodenectomy (group 1) and 32 patients received pancreaticoduodenectomy with simultaneous resection of the portal vein or the superior mesenteric vein or artery (group 2) followed by reconstruction. The immediate surgical outcomes and survivals were compared between the groups. Fifty-five patients with unresectable adenocarcinoma of the pancreas without liver metastasis who received only bypass operations (group 3) were selected for additional survival comparison.RESULTS: The median ages of patients were 67 years (range: 37-82 years) in group 1, and 63 years (range: 35-86 years) in group 2. All group 2 patients had resection of the portal vein or the superior mesenteric vein and three patients had resection of the superior mesenteric artery. The pancreatic fistula formation rate was 21.7% (10/46) in group 1 and 15.6% (5/32) in group 2 (P = 0.662). Two hospital deaths (4.3%) occurred in group 1 and one hospital death (3.1%) occurred in group 2 (P = 0.641). The one-year, three-year and five-year overall survival rates in group 1 were 71.1%, 23.6% and 13.5%, respectively. The corresponding rates in group 2 were 70.6%, 33.3% and 22.2% (P = 0.815). The one-year survival rate in group 3 was 13.8%. Pancreaticoduodenectomy with simultaneous vascular resection was safe for pancreatic head adenocarcinoma.CONCLUSION: The short-term and survival outcomes with simultaneous resection were not compromised when compared with that of standard pancreaticoduodenectomy.  相似文献   
65.

Purpose

To perform Preimplantation Genetic Diagnosis (PGD) on a paternal Brca2 unknown mutation carrier with early-onset breast cancer, whose paternal grandmother and mother had breast cancer at 60s.

Method

Elucidating the linkage via single sperm haplotyping on patient''s carrier brother, and identifying the genomic deletion via BLAST followed by PCR screening. PGD was subsequently conducted.

Result

The mutant allele was found by using 4 microsatellite and 2 intragenic SNP markers. Recombination was detected in 8 % of sperms. BLAST was utilized to locate putative hairpin structure(s), followed by PCR screening with seven sets of primers. A novel 2,596 bp deletion containing exon 15 ~ 16 was identified. Due to the severity of phenotype and the integrity of exon 11 encoding RAD51 binding domain, and the fact that the patient''s mother also had breast cancer at her 60s, we speculate a possible coexistence of maternal breast cancer risk allele(s). Embryo biopsy was performed on day 3. Unaffected morula and blastocyst were replaced on day 5, resulting in a singleton livebirth. A breast lump appeared in the patient after delivery without the presence of malignant cells.

Conclusion

Concerning the assisted reproductive option for breast cancer patients, the possibility of coexistence of multiple familial risk alleles and the significance of each mutation to the phenotype should be evaluated. To eliminate misdiagnosis resulting from recombination and/or allelic drop-out, both direct mutation detection and linkage analysis approaches may be necessary. BLAST is a very useful and cost-effective tool for identifying large genomic deletion.  相似文献   
66.
目的 探讨仰卧位MRI与站立位X线全脊柱片在青少年特发性脊柱侧凸(AIS)患者侧凸Cobb角、胸椎后凸角(TK)及腰椎前凸角(LL)测量上的差异性和相关性。方法 选取2008年1月—2016年1月行外科支具治疗或手术治疗且密切随访的120例AIS患者的站立位X线全脊柱片和仰卧位MRI全脊柱重建片资料进行回顾性分析。于站立位X线全脊柱正侧位片上分别测量主弯侧凸Cobb角、TK及LL。于患者仰卧位MRI全脊柱冠状面和矢状面重建片上的相同节段测量侧凸Cobb角、TK和LL。应用配对t检验及线性回归分析两组之间测量值的差异性及相关性。结果 120例站立位X线片上和仰卧位MRI上主弯侧凸Cobb角分别为33.8°±20.1°和24.9°±18.3°,TK分别为15.2°±9.7°和10.5°±7.7°,LL分别为43.6°±13.8°和37.1°±13.5°,差异均有统计学意义(P值均<0.01)。线性相关分析显示,站立位X线片上和仰卧位MRI上主弯侧凸Cobb角、TK和LL均有相关性,r分别为0.920、0.706和0.565(P值均<0.01)。线性回归分析得回归方程为:^Y站立位X线侧凸Cobb角=0.901×X仰卧位MRI侧凸Cobb角 +12.517、^Y站立位X线TK=1.055×X仰卧位MRI TK+3.865、^Y站立位X线LL=0.718×X仰卧位MRI LL+17.135。结论 仰卧位MRI与站立位X线片在AIS患者主弯侧凸Cobb角、TK及LL的测量具有差异且呈线性相关,利用仰卧位MRI可计算出站立位X线片上患者的侧凸Cobb角、TK和LL。  相似文献   
67.
Hepatitis due to hepatitis B virus(HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximabcontaining therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen(HBs Ag) and antibody to hepatitis B core antigen(antiHBc). Patients found to be positive for HBs Ag should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving highrisk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBs Ag-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies.  相似文献   
68.

Background  

Selection of patients with local failure of nasopharyngeal carcinoma (NPC) for appropriate type of salvage treatment can be difficult due to the lack of data on comparative efficacy of different salvage treatments. The purpose of the present study was to validate a previously published prognostic scoring system for local failures of NPC treated by radiosurgery based on reported results in the literature.  相似文献   
69.
目的:采用定量组织速度成像技术评价阿霉素诱导兔心肌病模型,并与常规经胸超声心动图比较其评估优势。方法:实验于2005-06/2006-08在大连医科大学完成。①实验分组及处理:取纯种新西兰白兔22只,雌雄不限,随机分成阿霉素组12只,给予阿霉素每次2mg/kg,以1g/L耳缘静脉注射,每周1次,注射8周;对照组10只每周注射2mL/kg生理盐水,共8周。②实验评估:每周应用HPSonos5500型彩色多普勒超声诊断仪(美国Agilent公司生产)对两组兔心脏进行左室收缩末期和舒张末期内径明、室间隔厚度、E峰、射血分数、左室短轴缩短率等常规超声参数测量,使用GEVivid7型彩色多普勒超声诊断仪(美国GE公司生产)进行收缩期和舒张期峰值速度、收缩期加速度定量组织速度成像参数测定。结果:22只兔进入统计。①对照组1~12周各参数与阿霉素组基础状态下比较无明显差异(P>0.05)。②第4周阿霉素组二尖瓣环运动的平均收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P均<0.05)。③第7周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),E峰较基础状态明显减低(P<0.05)。④第8周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),E峰较基础状态明显减低(P<0.01),左室收缩末期和舒张末期内径明显增大(P<0.05)。⑤第12周阿霉素组二尖瓣环运动的收缩期和舒张期峰值速度、收缩期加速度较基础状态明显减低(P<0.01),左室收缩末期和舒张末期内径明显增大(P<0.01),室间隔厚度、左室后壁厚度明显变薄(P<0.05),射血分数、左室短轴缩短率和E峰明显减低(P<0.01)。结论:定量组织速度成像参数可有效评价阿霉素诱导心肌病模型兔心肌的病理变化,较常规超声参数更敏感。  相似文献   
70.
目的:观察不同剂量雷公藤多甙对颈动脉球囊损伤后大鼠血管内皮生长因子、血管内皮细胞黏附分子1的影响,探讨雷公藤多甙在再狭窄防治方面的作用。方法:实验于2006-01/05在上海复旦大学医学院动物实验中心及上海瑞金医院烧伤研究所完成。①实验材料:SPF级SD雄性大鼠32只;雷公藤多甙(复旦复华药业)。②实验分组:随机分为正常对照组、模型组、雷公藤多甙小剂量组、大剂量组各8只。③实验干预:采用右颈动脉内膜剥脱法制备大鼠颈动脉狭窄模型。模型组术后予蒸馏水3mL/(kg·d)灌胃,雷公藤多甙小剂量和大剂量组分别给予雷公藤多甙30,60mg/(kg·d)灌胃。④实验评估:于术后2周麻醉后处死各实验组动物,取材,采用免疫组织化学方法检测大鼠颈总动脉血管内皮生长因子和血管内皮细胞黏附分子1含量。结果:32只大鼠全部进入结果分析。①正常大鼠颈动脉血管壁少量表达血管内皮生长因子,球囊损伤后表达量增加,雷公藤多甙大、小剂量组血管内皮生长因子表达的趋势与模型组基本相同,但表达量较模型组明显增加,雷公藤多甙小剂量组与模型组比较,P<0.05;大剂量组与模型组相比,P<0.01。②正常大鼠颈动脉管壁少量表达血管内皮细胞黏附分子1。球囊损伤后,模型组管壁血管内皮细胞黏附分子1表达增加;雷公藤多甙小剂量组和大剂量组管壁血管内皮细胞黏附分子1表达的趋势与模型组基本相同,但数量明显下降,雷公藤多甙小剂量组与模型组比较,P<0.05,大剂量组与模型组比较P<0.01。结论:雷公藤多甙能有效促进内皮细胞生成,减少内皮细胞间的黏附,对大鼠血管球囊损伤后的狭窄有一定的防治作用。  相似文献   
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