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1.
目的探讨依维莫司联合全反式维甲酸(简称维甲酸)逆转急性早幼粒细胞白血病(APL)细胞株NB4-R1耐药的作用。方法应用CD11b染色流式细胞术及硝基四唑氮蓝(NBT)还原实验检测两药联合应用对细胞分化的影响, 流式细胞术检测细胞周期情况, Annexin V/PI双染色检测细胞凋亡情况, 蛋白质印迹法检测自噬相关蛋白微管结合蛋白轻链3(LC3)、Beclin 1及早幼粒白血病-维甲酸受体融合蛋白(PML-RARα)、磷酸化核糖体S6激酶(P-P70S6K)、磷酸化4E结合蛋白1(P-4E-BP1) 等表达水平。结果与维甲酸组比较, 联用组能诱导耐药细胞株NB4-R1细胞的分化, 并将细胞增殖阻止在G 1期而对细胞凋亡无明显影响。100 nmol/L依维莫司组、1μmol/L维甲酸组、联用组、对照组NB4-R1细胞培养48 h后分化百分率分别为(2.29±0.57)%、(17.06±2.65)%、(54.47±4.91)%、(2.54±0.53)%; 处于G 1期的细胞百分率分别为(35.20±11.97)%、(33.54±6.25)%、(53.70±8.73)%、(27.40±6.01)%; 四组细胞凋亡细胞百分率分别为(2.30±0.14)%、(2.25±0.21)%、(2.40±0.28)%、(1.95±0.07)%。与维甲酸组比较, 联用组mTOR信号通路下游的P70S6K、4E-BP1分子磷酸化水平下降, LC3-II和Beclin 1的表达上调, 且能部分降解融合蛋白PML-RARα。 结论依维莫司联合维甲酸能诱导NB4-R1细胞分化, 且能阻滞细胞周期而不致细胞凋亡, 其机制可能与依维莫司联合维甲酸抑制mTOR信号通路激活自噬作用从而降解PML-RARα蛋白有关。  相似文献   
2.
白血病病人骨髓抑制期实施防感染措施时机的研究   总被引:5,自引:0,他引:5  
目的 :研究白血病病人在化疗期间 ,不同时间实施预防感染护理的效果。方法 :对照组在化学疗法结束后给予预防感染的护理措施 ,实验组在化学疗法开始前 3~ 7d实施预防性护理措施。观察两组病人感染发生率。结果 :感染发生率实验组明显低于观察组。结论 :在化学疗法开始前实施预防性护理措施有助于降低感染发生率  相似文献   
3.
Purpose Studies on musculoskeletal manifestations (MSM) of childhood acute lymphoblastic leukemia (ALL) have yielded variable findings with regard to their clinical impact. We investigated the significance for differential diagnosis, treatment and outcome of musculoskeletal complaints as presenting symptoms of ALL, and their correlation with leukemia immunophenotypes, for which data is lacking. Methods Data on 783 children in the national study for childhood ALL between 1984 and 2003 were reviewed retrospectively. Statistical analysis examined possible relationships between MSM at the time of diagnosis and demographic and clinical data, biological features of leukemia (peripheral blood counts, immunophenotype and main cytogenetic aberration), response to initial prednisone treatment, and outcome. Results Of 765 children with data on orthopaedic complaints, 240 presented with MSM (31.4%). Among these children, B cell precursor (BCP) was much more common (209/576, 36.3%) than T cell ALL (25/176, 14.2%). Patients with MSM had lower white blood cell counts (WBC) (median of 9 vs. 20 × 109/L, P < 0.001) and percentage of blast cells in the peripheral blood at diagnosis compared to those without (median of 27 vs. 53%, P < 0.001). Hepatomegaly and splenomegaly were less common in MSM group (67 vs. 53% <3 cm, P < 0.001, and 63 vs. 50% <3 cm, P < 0.001, respectively). Poor response to initial treatment with prednisone was recorded in 7.1% of patients with MSM versus 11.5% of those without (P = 0.086). The analysis revealed no independent effect of MSM on event-free survival (EFS), after correcting for differences in EFS related to immunophenotype or initial WBC. Conclusions MSM occur mostly in children with BCP ALL who present with less involvement of extramedullary organs, low peripheral blood blasts and white blood cells counts. These findings highlight the importance of including ALL in the differential diagnosis of MSM even in the presence of an apparently normal peripheral blood count. Our study also suggests that MSM are caused by leukemic cells with enhanced biological propensity to remain relatively confined within the intramedullary bone-marrow space.  相似文献   
4.
Fas和mdr-1在急性白血病的表达及其相关性研究   总被引:1,自引:0,他引:1  
本研究应用流式细胞仪 (FCM)直接免疫荧光法和半定量RT PCR方法分别测定 5 9例初发急性白血病(AL)患者治疗前及完全缓解 (completeremission ,CR)后骨髓Fas和mdr 1mRNA表达情况 ,旨在探讨Fas和mdr 1在AL的表达及二者在多药耐药 (multidrugresistance ,MDR)中的相关性。结果显示 :Fas在初发AML阳性表达率比ALL高 ,两表达率间有差异 (P <0 .0 5 ) ,mdr 1在AML和ALL阳性表达率间无差异 (P >0 .0 5 ) ,Fas 与mdr 1 有负相关性 (r =- 0 .2 82 ,P <0 .0 5 ) ;经单因素及多因素COX分析 ,Fas和mdr 1独立于其他参数 ,更具判断预后价值 ;在Fas 与Fas-的AML和AL ,CR率均有显著性差异 (P <0 .0 1) ,在mdr 1 、mdr 1-的AML和AL中的CR率有显著性差异 (P <0 .0 1) ;经Logrank检验 ,Fas 与Fas-组CR率及中数缓解时间有显著性差异 (χ2 =7.35 ,P =0 .0 0 6 7) ,mdr 1 与mdr 1-组CR率及中数缓解时间有显著性差异 (χ2 =10 .71,P =0 .0 0 11)。结论 :Fas、mdr 1与疗效高度相关 ;Fas阳性表达可能是AL预后良好因素 ;mdr 1为疗效差、预后不良的重要因素。  相似文献   
5.
 Granulocytic sarcoma is an uncommon extraskeletal tumor most frequently associated with leukemia. We present a case of bone location with unusual pattern in a patient with no evidence of myeloproliferative disorder at presentation or follow-up.  相似文献   
6.
实时荧光定量PCR检测PML-RARα融合基因的临床应用研究   总被引:1,自引:0,他引:1  
目的 利用PML-RARα融合基因作为标志物,应用实时荧光定量PCR技术,监测急性早幼粒细胞白血病(APL)微小残留病(minimal residual disease,MRD)患者体内病毒的状态,探讨预测APL复发风险的方法.方法 利用本实验室建立的定量检测APL患者PML-RARα融合基因的方法,对25例处于初诊、完全缓解(complete remission,CR)、复发等不同阶段的APL患者进行了PML-RARα融合基因的定量检测,并对其中6例患者的MRD状态进行了动态监测.结果 应用荧光定量PCR技术分析患者初诊、CR和复发状态的PML-RARα基因对数值(lg)水平,结果 显示有统计学意义(x2=6.847,P<0.05);随访期患者的PML-RARα对数值(lg)水平变化较大:初诊时较高(-0.61±0.79),CR时下降(-1.31±0.62),复发时又出现上升(-0.57±0.44),提示若该患者在CR时的对数值呈现上升趋势,患者复发的机率大.结论 应用实时荧光定量(RQ)-PCR技术定量检测PML-RARα融合基因,对监测APL患者MRD状态具有临床适用性,随访期的MRD动态追踪监测具有预后价值.  相似文献   
7.
Exposure of murine erythroleukemia cells (MELCs) to nicotinamide (NA) or its synthetic analog N′-methylnicotinamide (N′-MN) reduces cell growth and induces terminal differentiation, marked by increased heme and globin accumulation. On the contrary, 1-methylnicotinamide (1-MN), the primary metabolite of excess NA, was found to stimulate cell growth and reduce spontaneous differentiation of cultured MELCs. Log phase MELCs exhibited up to 50% higher cell density above untreated cells when cultured for up to 96 h with 2.5 mM 1-MN. When combined with NA or several chemically-unrelated inducers of hemoglobin synthesis in cultured MELCs, 1-MN reduced the globin mRNA levels and heme accumulation by 40–80%. 1-MN was able to inhibit heme production if present during only the first 24–48 h after NA exposure. Pre-treatment with 1-MN could not confer resistance of cells to effects of NA, suggesting the inhibition is reversible. Commitment to differentiate in semisolid medium by the most potent inducer, 5 mM N′-MN, was inhibited up to 95% by 2.5 mM concentrations of 1-MN. It appears that 1-MN has opposing effects on growth and induction of differentiation than those seen in MELC cultures exposed to NA or N′-MN.  相似文献   
8.
应用逆转录PCR结合同位素定量分析,对32例儿童白血病患者的多源耐药基因表达水平进行了研究。结果显示,初发病人的表达均较低,复发病人表达较高,缓解期病人表达程度介于两者之间,为探讨多源耐药基因表达水平与临床化疗之间的相关性及逆转克服多源耐药性药物的应用,提供了一定的理论依据。  相似文献   
9.
The purpose of this study was (a) evaluation of dynamic contrast-enhanced MR imaging of normal bone marrow versus malignant bone marrow infiltrations in patients with proven B-cell-type chronic lymphocytic leukemia (B-CLL) and (b) correlation with the clinical stage according to Binet (stages A, B, C) and response to therapy. Bone marrow imaging of the lumbar spine, pelvis, and proximal femurs was performed at 1.5 T in 45 patients without known malignancy and in 30 patients with B-CLL. The differences between opposed-phase and in-phase dynamic gradient-echo sequences before and up to 10 minutes after intravenous application of .1 mmol/kg body weight of gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) were evaluated in normal bone marrow. The contrast-enhancement patterns of normal and malignant bone marrow were compared using the opposed-phase dynamic gradient-echo sequence. Ten of the patients with bone marrow infiltrations (Binet stage C) additionally underwent MR imaging follow-up during therapy. Opposed-phase gradient echo sequences demonstrated a signal decrease of normal bone marrow, and in-phase gradient echo sequences demonstrated a signal increase of normal bone marrow after administration of Gd-DTPA. The dynamic signal intensity time courses differed significantly (P < .05) between Binet stages B and C and controls as well as among the three Binet stages of B-CLL. In the 10 patients followed during therapy, MR imaging sensitively demonstrated response (n = 6), nonresponse (n = 2), or relapse after initial response (n = 2). In out-of-phase imaging, both normal bone marrow and initial bone marrow infiltration in CLL stage Binet A show signal decrease after administration of contrast agent, whereas there is increase in signal intensity in higher-grade bone marrow infiltration in Binet stage B or C disease. The signal loss of normal bone marrow in out-of-phase imaging is a phase effect rather than a T2* effect. The differentiation of initial from higher-grade bone marrow infiltration on out-of-phase images relies solely on a shift in the fat/water ratio.  相似文献   
10.
目的 探讨在全反式维甲酸 (ATRA)治疗急性早幼粒细胞白血病 (APL)前后弥漫性血管内凝血(DIC)发生率与D 二聚体含量的关系及意义。方法 应用ELISA法检测 30例APL患者 (包括 12例合并DIC患者 )发病时及应用ATRA治疗后D 二聚体水平的变化 ,并与正常对照组比较。结果  30例APL患者治疗前血浆D 二聚体水平 (2 .38± 0 .98mg/L)较正常对照组 (0 .2 5± 0 .0 9mg/L)明显升高 (P <0 .0 1) ,其中 12例并发DIC者(2 .5 2± 0 .12mg/L)明显高于 18例不并发DIC者 (2 .18± 0 .96mg/L)。结论 APL患者D 二聚体检测值随维甲酸治疗逐渐降低 ,并可预测ATRA治疗过程中DIC变化及预后。  相似文献   
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