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51.
As a source of transplantable stem cells, the CD34^+ subpopulation in human umbilical cord blood (HUCB) has been used extensively to treat some hematopoietic system diseases. However, whether CD34^+ cells hold the therapeutic potential to cerebral ischemia is unknown. The purpose of this study was to observe the recovery of neural function after transplantation of CD34^+ cells derived from HUCB into ischemic cerebral tissue in rats.  相似文献   
52.
目的探讨孤立性纤维性肿瘤(SFT)的临床病理、免疫组化特征及鉴别诊断。方法报道一例肺的孤立性纤维性肿瘤,结合文献对本病的临床病理学特征进行探讨。结果临床主要表现为逐渐加重的胸闷、气急。X线胸片显示右下肺有一团块状阴影,边界清。肿瘤呈结节状,位于右下肺,紧靠肺膜下10cm×8cm×7cm,切面灰白,质嫩。镜下:肿瘤主要由短梭形细胞构成,有多种排列方式。免疫组化CD34阳性。结论SFT是一种少见的间质源性的梭形细胞肿瘤,须与多种其它梭形细胞肿瘤进行鉴别,免疫组化有助于鉴别诊断。约10%~30%的SFT具有恶性的生物学行为,表现为局部复发或远处转移,其组织构象并不能完全预测其预后,患者术后定期随访是必要的。  相似文献   
53.
目的研究细胞因子诱导杀伤细胞(cytokine induced killer,CIK)对慢性粒细胞白血病(chronic myeloid leukemia,CML)中G0期原始干细胞(CD34+)的杀伤作用。方法5例CML慢性期患者外周血标本在体外诱导培养CIK细胞,流式细胞仪(FCM)检测其表型。G带法检测CIK细胞核型。应用免疫磁珠技术分选CD34+CML白血病细胞,AO染色后利用FCM检测CIK细胞对G0期CD34+CML白血病细胞的杀伤作用。半固体培养法检测CIK细胞对正常骨髓CFU-GM、BFU-E集落的影响。结果CIK细胞在培养第3周时,CD3+细胞数量达(97.29±3.55)%,CD3+CD56+细胞绝对数量增加了356倍,染色体分析证实,CIK细胞为正常核型,流式细胞仪检测CIK细胞对G0期CD34+CML白血病细胞平均杀伤率为66.73%。对照组与加入CIK细胞组的CFU-GM集落数分别为150±16和145±20,差异无统计学意义,P=0.38;两组的BFU-E集落数分别为68±5和65±8,差异无统计学意义,P=0.23。集落类型、大小两组相似,差异无统计学意义,P=0.46。结论CIK细胞可从CML患者外周血中大量扩增,来源于正常淋巴细胞,对G0期CD34+CML白血病细胞有明显抑制作用,对正常造血前体细胞无抑制作用,可作为过继细胞免疫治疗的效应细胞治疗CML。  相似文献   
54.
目的:研究腋淋巴结阴性(ph node negative,LN N)乳腺癌中PTEN蛋白的表达,探讨与微血管密度lym(VD)及患者预后的关系。方法:应用免疫组化S-P法检测81例LN N乳腺癌及20例癌旁乳腺组织中PTEN和MCD34蛋白的表达,分析与各临床病理因素和预后的关系。结果:32.6%的患者PTEN蛋白表达减低或完全阴性表达,PTEN与乳腺癌病理分级,ER状态和复发转移显著相关;PTEN阳性表达组的5年生存率(83.7%)明显高于阴性表达组(66.7%)(P<0.05);PTEN的表达与M VD呈显著的负相关关系(r=-0.552,P<0.01)。结论:PTEN缺失是乳腺癌发生过程中的多发事件,并有抑制血管生成的作用,PTEN缺失和高M V D的LNN乳腺癌患者5年生存率低,两者的检测有助于提高评估LN N乳腺癌患者术后生存的准确性。  相似文献   
55.
Objective To investigate the expression and relationship of TIP30(HIV-1 Tat interactive protein 2), vascular endothelial growth factor (VEGF) and MVD (detected by CD34) in the angiogenesis of human brain astrocytomas. Methods Expression of TIP30, VEGF and CD34 in 19 cases of normal brain tissue and 71 cases of astrocytoma were immunohistochemically examined with Elivision plus two-step method. Results The positive expression of TIP30 could be seen in cytoplasm of neuroglial cells and neurons of 19 normal brain tissues. The positive expression rate of TIP30 in 71 cases of astrocytoma was 33.80 % (24/ 71). The positive expression rate of TIP30 in astrocytoma of different grades was 52 % for grade Ⅱ, 34.78 % for grade Ⅲ and 13.04 % for grade Ⅳ. The positive expression rate of TIP30 in high grade (Ⅲ+Ⅳ) of astrocytoma was found significantly lower than that in low grade(Ⅱ) (χ2=5.71, P <0.05); The expression of VEGF and MVD detected by CD34 in astrocytomas were higher than that in normal brain tissue and increased as the tumor grade increased; In astrocytoma, the negtive correlation was found between the expression of TIP30 and VEGF (r=-0.428, P<0.05); no correlation was found between TIP30 and MVD(r=-0.065, P 0.05); the positive correlation was found between VEGF and MVD(r=0.684, P<0.01). Conclusion The positive expression rate of TIP30 in normal brain tissue is significantly higher than that in astrocytoma. The positive expression rate of TIP30 significantly decreases as the pathological grade of the astrocytoma increases; The expression of TIP30 and VEGF is negatively correlated in astrocytoma.  相似文献   
56.
Previous studies have revealed that hematological disorders associated with trichothecenes intoxication in humans could result from hematopoiesis inhibition. The most frequent and potent trichothecene mycotoxins are T-2 toxin and deoxynivalenol (DON), respectively. Apoptosis induction by these two toxins was investigated in vitro on human hematopoietic progenitors (CD34+ cells). Hoechst coloration, DNA fragmentation and annexin-V/PI labeling in flow cytometry showed that T-2 toxin, in contrast to DON, induced apoptosis in CD34+ cells. T-2 toxin effect was dose- and time-dependent with a significant increase of apoptotic cells as early as 3 h after incubation at 10−7 M and a maximum reached at 12 h. This observation evidenced the high sensitivity of hematopoietic progenitors to T-2 toxin. The inhibition of T-2 toxin-induced apoptosis by a pan-caspase inhibitor (Z-VAD-fmk) suggested the involvement of caspases. The proportional increase of caspase-3 specific activity (DEVDase) with T-2 toxin concentration confirmed its role in the process. After incubation of CD34+ cells with T-2 toxin, in conditions that induced apoptosis, clonal expansion of granulo-monocytes, erythrocytes and megakaryocytes precursors was dose-dependently inhibited. The hematological effects observed in T-2 toxin mycotoxicosis could then be assigned to hematopoiesis inhibition by apoptosis. Different mechanisms that need to be further elucidated are involved in DON myelotoxicity.  相似文献   
57.
Abstract: Although the effect of sucrose on the physical stability of proteins has been well documented, its impact on their chemical stability is largely unknown. The aim of this study was to investigate the potential effects of sucrose on the structural conformation of human brain natriuretic peptide [hBNP (1–32)] and the synthetic human parathyroid hormone [hPTH (1–34)], and link these effects to chemical degradation pathways of these peptides. The stability of hBNP (1–32) and hPTH (1–34) was studied at pH 5.5. Aggregation was monitored using size exclusion high‐performance liquid chromatography (SE‐HPLC), whereas oxidation and deamidation products were measured by reversed phase (RP) HPLC. Fourier transform infrared (FT‐IR) spectroscopy was used to study the peptides’ conformation. Sucrose retarded aggregation, deamidation, and oxidation of hBNP (1–32) and hPTH (1–34), with a maximum effect at relatively high concentrations (as much as 1 m ). FT‐IR spectroscopy indicated that sucrose maintained the native conformation of hBNP (1–32) and induced small conformation changes in the hPTH (1–34) structure. Sucrose enhanced the stability of hBNP (1–32) and hPTH (1–34) in liquid formulations. The stabilizing effect of sucrose was due to a large extent to retardation of oxidation and deamidation of hBNP (1–32) and hPTH (1–34).  相似文献   
58.
【目的】观察miR-34a在低氧诱导的大鼠肺动脉平滑肌细胞增殖中的作用并探讨其可能的机制。【方法】原代分离和培养大鼠肺动脉平滑肌细胞(PASMC),并给予3%低氧处理后,用Real-time PCR法检测miR-34a和Notch1mRNA在大鼠PASMC中的表达;低氧条件下用细胞转染法过表达和抑制miR-34a、沉默Notch1基因的表达后用EDU法观察细胞增殖情况,并用Real-time PCR和Western blot法检测细胞核增殖抗原PCNA的表达。【结果】分离和培养大鼠PASMC并给予3%低氧处理后,大鼠PASMC中miR-34a表达明显降低,且低氧48h降低较明显,组间差异有统计学意义(P<0.05)。而Notch1的表达明显增高,且48h增高较明显,组间差异有统计学意义(P<0.05)。此外,过表达miR-34a和沉默Notch1后会显著抑制低氧引起的细胞增殖,抑制miR-34a的表达后则会促进细胞增殖,且组间差异有统计学意义(P<0.05)。【结论】在低氧诱导的PASMC细胞增殖过程中miR-34a参与了PASMC的增殖过程,且可能是通过上调Notch1引起了细胞增殖。  相似文献   
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