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451.
目的:培养条件是影响骨髓间充质干细胞生物学特性的重要因素。实验考察换液频率对兔骨髓间充质干细胞增殖分化及代谢特性等的影响。方法:实验于2005-03/2005-06在华东理工大学生物反应器工程国家重点实验室完成。①实验材料:1月龄新西兰大白兔购自上海市淞江车墩实验动物良种场。实验过程中对动物处置符合动物伦理学标准。②实验方法:采用密度梯度离心法从兔股骨骨髓中分离得到骨髓间充质干细胞,体外培养扩增后,取生长良好的第3代细胞分别以24,48,72h时间间隔进行换液培养。③实验评估:观察细胞形态学变化,测定细胞生长曲线同时进行乳酸和氨代谢分析,并对几种条件下收获的细胞进行集落形成和成骨分化检测。结果:①每24h换液的细胞最早进入对数生长期,第5天达到增殖顶点,最大细胞数目可达3.44×105,分别是48h和72h换液频率的1.43倍和1.71倍。②每48h换液条件下收获的细胞具有最强的集落形成能力,明显高于每24h和每72h换液条件下收获的细胞。③3种换液频率条件下收获的细胞经成骨诱导后茜素红染色均为阳性,其中每48h换液的细胞胞外钙基质分泌最高。④3种换液频率条件下细胞的代谢曲线无明显差异,乳酸和氨均维持较低浓度,分别在5mmol/L和2mmol/L以下。结论:①换液频率对骨髓间充质干细胞的影响具有双向性。提高换液频率促进骨髓间充质干细胞的增殖,同时也加速了干细胞特性的丢失,导致集落形成能力和成骨分化能力下降。②普遍采用的三四天换液不能提供适合骨髓间充质干细胞生长同时利于干细胞特性维持的营养环境,提示可通过常规培养条件的优化使其有利于骨髓间充质干细胞执行对称的细胞分裂。  相似文献   
452.
BACKGROUND: DIDS (4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid) inhibits the formation of serum-or plasma-induced rouleaux through its ability to bind to band 3 on red cell membranes. This property of DIDS was evaluated in the serologic testing of specimens exhibiting rouleaux. STUDY DESIGN and METHODS: Optimal test conditions for DIDS treatment of reagent red cells were determined by varying the volume and concentration of DIDS solution and the incubation temperature and duration and comparing the results of antibody screening procedures using specimens that exhibit macroscopically visible rouleaux. Blind titration studies compared untreated and DIDS-treated red cells to evaluate the maintenance of antigen integrity. The use of DIDS-treated red cells for antibody detection and identification was evaluated by comparing the results in donor specimens containing antibodies with those in untreated and DIDS-treated selected panel cells. In addition, 4-percent (wt/vol) dextran in serum was used to induce rouleaux formation as a way of determining the capability of DIDS to resolve ABO serum grouping discrepancies. RESULTS: Complete inhibition of rouleaux formation occurred when reagent red cells were treated by incubation at 37 degrees C for 10 minutes with 150 microliter (approx. 5 drops) of 0.05 mg per mL of DIDS in 0.9-percent NaCl. There were no significant differences in titration scores of untreated and DIDS-treated red cells tested with the 19 antisera used to assess antigen integrity. Antibody identification studies showed that DIDS-treated reagent red cells reacted similarly to untreated reagent red cells. In addition, DIDS resolved dextran-induced ABO serum grouping discrepancies. CONCLUSION: DIDS effectively resolved the serologic problems associated with the presence of rouleaux, without affecting the results of the test system itself. Implementation of this method to inhibit the rouleaux-forming properties of serum and plasma specimens can be useful in serologic testing.  相似文献   
453.
Adverse reactions in patients transfused with cryopreserved marrow   总被引:2,自引:0,他引:2  
Marrow is cryopreserved for use in autologous bone marrow transplants, but little is known of the incidence of reactions in patients transfused with these cryopreserved marrows. Reactions in patients transfused during a 4-year period with 134 autologous marrows cryopreserved in dimethyl sulfoxide (DMSO) were compared with those in patients transfused with marrow that had been collected from HLA-compatible donors and that had not been cryopreserved. Patients transfused with cryopreserved marrow had significantly more nausea (44.8 vs. 14.1%; p less than 0.0005), vomiting (23.9 vs. 8.5%; p less than 0.01), chills (31.3 vs. 1.4%; p less than 0.0005), and fever (17.9 vs. 0%; p less than 0.005) than patients transfused with fresh allogeneic marrow. The incidence of emesis correlated with the dose of DMSO received, but that of nausea did not. All cryopreserved marrows were cultured for bacteria at the time of transfusion and 17 (12.7%) were found to be positive. Only 1 of the 17 patients transfused with culture-positive marrow developed sepsis during the transplant course with the same organism that was present in the transfused marrow. Although the reactions in donors transfused with cryopreserved marrow were readily treated, this study suggests that the incidence of some reactions might be decreased by reducing the dose of DMSO transfused. Bacterial contamination of transfused marrow was a worrisome complication, and efforts should be made to improve marrow collection and processing techniques to minimize that risk.  相似文献   
454.
455.
Patients with disseminated follicular non-Hodgkin's lymphoma (NHL) are only occasionally cured with standard chemotherapy regimens. Although most of these tumors are initially responsive to chemotherapy, in 40% to 70% of patients the lymphoma will eventually transform to an NHL of higher grade malignancy and a poorer prognosis. We treated 18 patients having an original diagnosis of follicular NHL with high-dose therapy and autologous bone marrow transplantation. The lymphomas of 10 of the patients had already undergone histologic transformation and eight still had a follicular histologic pattern. The former group had been followed for a longer time from the diagnosis of NHL and had been more extensively treated with conventional chemotherapy regimens. All eight patients with follicular NHL at the time of transplantation are alive for 246+ to 1,804+ days and seven of the patients are in complete remission. In contrast, of the 10 patients in histologic transformation only 1 is alive and in CR. This reflects the inability of these patients to tolerate the high-dose chemotherapy and myelosuppression as well as resistance of their lymphoma to this therapy. This difference in survival between the two groups was highly significant (P = .002). We conclude that the outcome of patients with follicular NHL transplanted early before histologic transformation is better than for those who are transplanted later in the course of their illness. Because of the relapsing behavior of follicular NHL, a longer follow-up is necessary to prove any impact on the natural history of the disease.  相似文献   
456.
目的:研究表明,结蛋白和波形蛋白可反映肌肉损伤再生的情况,同时结蛋白可反应肌力的大小。比较特发性和先天性脊柱侧凸患者顶椎处凹凸两侧椎旁肌形态和结蛋白及波行蛋白的表达,探讨椎旁肌在特发性脊柱侧凸发生发展中的作用。方法:①选择2005-07/2006-11间南方医科大学南方医院脊柱骨病科收治的部分特发性脊柱侧凸患者12例,Cobb角平均73.8°;先天性脊柱侧凸患者5例,Cobb角平均36.0°;腰椎间盘突出症患者2例和胸腰椎管内占位性病变患者3例作为正常对照。所有患者年龄均在10~20岁。②对脊柱侧凸患者顶椎凹凸两侧及正常对照组患者椎旁肌进行活检,术前均签署知情同意书。③采用光镜和电镜下观察椎旁肌的形态改变;SP法分别对光镜切片的结蛋白和波行蛋白进行免疫组织化学染色,在光镜下观察蛋白表达;应用图像分析系统测量结蛋白免疫组织化学染色后反应椎旁肌蛋白表达强弱的吸光度(A)。结果:22例患者全部进入结果分析。①椎旁肌组织形态:特发性脊柱侧凸患者椎旁肌在光镜及电镜下均有病变,凹侧椎旁肌病变较重,凸侧椎旁肌相对正常。②结蛋白免疫组织化学的阳性表达:结蛋白在各组椎旁肌中均有不同程度的表达,组间比较差别显著(P<0.01)。特发性脊柱侧凸及先天性脊柱侧凸患者椎旁肌在顶椎凸侧比正常组结蛋白表达稍强(0.2727±0.0478,0.2768±0.0372,0.2429±0.0272,P<0.05),特发性脊柱侧凸及先天性脊柱侧凸患者椎旁肌在顶椎凹侧相对于正常组表达减弱(0.1898±0.0258,0.1869±0.0306,0.2429±0.0272,P<0.05)。③波行蛋白免疫组织化学的阳性表达:各组间椎旁肌肌纤维内均无波形蛋白表达。特发性脊柱侧凸与先天性脊柱侧凸患者同侧椎旁肌两组间在形态和结蛋白及波行蛋白表达无明显差别(P>0.05)。结论:特发性脊柱侧凸患者椎旁肌内波形蛋白表达均为阴性,提示椎旁肌不存在再生现象。与先天性脊柱侧凸类似,特发性脊柱侧凸患者椎旁肌结蛋白表达凸侧增强及凹侧减弱为继发性改变。  相似文献   
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