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61.
The sudden appearance of prolactin-releasing cells during the early postnatal period of the rat is initiated by a small milk-borne peptide. Depriving newborn rats of this early milk factor severely retards mammotrope differentiation during the neonatal period. In the present work, we extend our study of early milk deprivation to the adult. To this end, newborn litters were crossfostered onto mothers that had given birth the same day or one week earlier in order to deprive pups in the latter group of early milk. At 5, 15, and 30 d of age, rats deprived of such milk had decreased percentages of mammotropes (as measured by reverse hemolytic plaque assay, RHPA) when compared to nondeprived animals (P<0.05). By 45 d, the percentage of mammotropes was similar for the two crossfostered groups (P>0.1) and this persisted through d 60. Subsequently, we assessed the secretory capacity of mammotropes from 60-d old rats to secretagogues and found that early milk deprivation had no effect on basal prolactin release (P>0.1), but that it augmented hormone secretion evoked by thyrotropin-releasing hormone (TRH, 100 nM; P<0.01). The inhibitory response to dopamine (DA; 1 μM) and the stimulatory response to angiotensin II (AGII; 100 nM) were not altered by early milk deprivation (P>0.1). Taken together, these results demonstrate that factors in milk from early lactation are required for normal mammotrope differentiation, and that the delay induced by early milk deprivation leads to altered secretory function of mammotropes in adult animals.  相似文献   
62.
对甲状腺机能亢进症(甲亢)患者进行了临床辨证分型,同步观察甲皱微循环及检测TT_3 TT_4 FT_4I、吸~(131)碘率,探讨它们之间的关系。结果表明甲亢患者微循环积分明显高于对照组(P<0.01),但不同类型甲亢的血淤情况亦不相同。心肝火旺型的微循环积分低于气滞痰凝型和血瘀型,但TT_3、TT_4、FT_4I明显增高;气滞痰凝型居中;血淤型的微循环积分明显增高,但TT_3、TT_4、FT_4I低于其他两型。吸~(131)碘率三型间无差异(P>0.05)。  相似文献   
63.
64.
We have devised a medium which supports the continuous growth of hepatocytes without losing their replicative potential and differentiation capacity for a longer period. The medium HCGM, contains four key substances in addition to foetal bovine serum. They are epidermal growth factor, nicotinamide, ascorbic acid 2-phosphate and dimethylsulphoxide. When a non-parenchymal cell fraction containing small hepatocytes and non-parenchymal cells was cultured in HCGM, small hepatocytes grew clonally and differentiated into cells expressing either mature hepatocyte marker proteins or biliary cell marker proteins. Thus, for the first time, we showed the presence of a small compartment of bipotent and highly replicative clonogenic hepatocytes in the rat adult liver. HCGM also supported the growth of stellate cells (Ito cells) which were in the original preparation, suggesting the important role of stellate cells for the successful cultivation of hepatocytes. Together, these results suggest that a microenvironment is produced as a result of cooperative interactions between hepatocytes and stellate cells: one which stimulates the growth and differentiation of clonogenic hepatocytes.  相似文献   
65.
Rhombencephala from rat embryos were processed as whole-mounts for immunocytochemical detection of monoaminergic cell populations, using antibodies to tyrosine hydroxylase (TH) and serotonin (5-HT). Specific advantages of the whole-mount technique over the classical serial-section method were that even isolated immunoreactive (IR) cells could be detected easily, and three-dimensional relationships could be ascertained without the need for serial reconstruction. Embryos between embryonic days (E) 12 and 16 (the day following nocturnal mating being considered as E1) were used in this study. Both TH and 5-HT immunoreactivities were already detectable at E12, even in the smallest embryos (crown-rump length: 6 mm), but there was a striking difference in the number and regional distribution of these two types of IR cells. TH was expressed in several cell groups located in the rostral rhombencephalon (the presumed anlage of the A4-7 complex) as well as in the caudal rhombencephalon (the presumed anlagen of groups A1-2 and C1-3), whereas 5-HT was expressed in very few cells located near the rostral border of the rhombencephalon (presumed anlage of the B4-9 complex). Although the three-dimensional distribution of the TH-IR cell groups underwent some modifications during the period studied, its general pattern remained relatively stable after E12. This contrasted with the sequential appearance of the 5-HT-IR cell groups and their spatial transformations during this period. Using the rhombencephalic isthmus as a landmark, we found that conspicuous 5-HT-IR fibre bundles penetrated into the mesencephalon from E13 onwards, but that the 5-HT IR cell bodies were exclusively located caudal to the borderline between the mesencephalon and the rhombencephalon (the rhombencephalic isthmus). We therefore suggest the term "rostral rhombencephalic raphe nuclei" for the rostral 5-HT cell groups instead of "mesencephalic raphe nuclei," which is a misnomer. Close spatial association between TH and 5-HT-IR elements was observed mainly in the caudal rhombencephalon, where 5-HT-IR fibres coursed through an area containing numerous TH-IR cell bodies (the presumed anlagen of groups A1-2 and C1-3).  相似文献   
66.
To find out whether glial cells proliferate in the corpus callosum of adult mice, two series of experiments were carried out. The first one made use of 9-month-old "aged" male mice. Some of them were given 3H-thymidine as a 2-hour pulse to examine which cells became labeled and, therefore, had the ability to divide. Others were sacrificed after a continuous infusion of 3H-thymidine for 30 days to examine whether the label would then appear in different cells. In other aged animals, the 30-day infusion was followed by 60 or 180 days without 3H-thymidine to determine whether cells retained or lost their label with time. A second series of experiments was carried out in 4-month old "young adult" male mice to seek confirmation of the main conclusions. Following the 3H-thymidine pulse given to aged mice, only immature glial cells were labeled. After a 30-day infusion, 12.1% astrocytes and 1.1% oligodendrocytes were labeled, so that the net daily addition rate of astrocytes averaged 0.4% and of oligodendrocytes, 0.04%. In young adult mice, the rate after a 7-day infusion averaged 0.9% for astrocytes and 0.08% for oligodendrocytes. However, when the 30-day infusion into aged mice was followed by 60 and 180 days without 3H-thymidine, the labeled astrocytes decreased to 5.3% and 0%, respectively, whereas the number of labeled oligodendrocytes did not change significantly. The interpretation of the results is that the immature cells present in the corpus callosum of mice continue dividing throughout life and their progeny give rise to astrocytes and oligodendrocytes. In the case of astrocytes, the production of new cells occurs in parallel with a loss, so that the astrocyte population turns over. In the case of oligodendrocytes, there is a small production of new, apparently stable cells.  相似文献   
67.
目的 探讨可溶性白细胞分化抗原14(soluble cluster of differentiation antigen 14,sCD14)、血管生成素2(angiopoietin 2,Ang2)、C反应蛋白(C-reactive protein,CRP)与急诊创伤骨折伴多发伤患者病情转归的关系及意义。 方法 选取创伤骨折伴多发伤患者324例,根据患者出院时病情转归情况分为良好组(275例)、不良组(49例),比较2组一般资料、sCD14、Ang2、CRP水平,应用Pearson分析sCD14、Ang2、CRP与损伤严重程度评分(injury severity score,ISS)关系,采用Cox回归分析急诊创伤骨折伴多发伤患者病情转归的相关影响因素,采用受试者工作特征曲线(receiver operating characteristic,ROC)分析sCD14、Ang2、CRP对病情转归预测价值。 结果 不良组ISS评分高于良好组(P<0.05);不良组sCD14、Ang2、CRP高于良好组(P<0.05);sCD14(r=0.785)、Ang2(r=0.778)、CRP(r=0.842)与ISS评分呈正相关(P<0.05);sCD14、Ang2、CRP均是预后相关独立危险因素(P<0.05);sCD14、Ang2、CRP预测病情转归的ROC下面积(area under the curve,AUC)依次为0.813、0.757、0.749;挑选出预测敏感度最高(sCD14)、特异度最高(Ang2)的两个指标进行sCD14+Ang2的联合ROC分析显示,两者联合预测病情转归的AUC为0.935,大于任一单一指标(P<0.05)。 结论 sCD14、Ang2、CRP与急诊创伤骨折伴多发伤患者病情严重程度及病情转归有关,均可作为预测病情转归的标志物,但联合检测sCD14、Ang2能提高预测可靠性,为临床诊疗及护理提供更准确的参考信息。  相似文献   
68.
人羊膜间充质干细胞(hAMSC)具有来源丰富、分离简单的优点。hAMSC在组织修复中具有支持造血、再生、免疫调节、抗纤维化等作用。本文对羊膜间充质干细胞在各个系统疾病治疗的研究进行了综述,旨在为羊膜间充质干细胞的应用提供参考。  相似文献   
69.
目的 探讨淫羊藿苷(ICA)对人牙髓干细胞(DPSC)神经向分化的作用。方法 分离培养DPSCs后,采用不同浓度ICA(0.01μmol、0.10μmol、1.00μmol、10.00μmol)处理DPSCs。CCK-8法检测ICA对细胞增殖活力的影响,确定其最佳促DPSCs增殖浓度。分别进行细胞形态学观察和Nestin细胞免疫荧光检测。Western blotting检测DPSCs神经向分化相关蛋白Nestin、βⅢ-tubulin及NSE的表达。结果 不同浓度ICA细胞相对活力值比较,差异有统计学意义(P <0.05),其中以0.10μmol ICA细胞相对活力最高。与对照组比较,ICA组神经球的直径增加(P <0.05),Nestin荧光强度增强(P <0.05),Nestin、βⅢ-tubulin、NSE蛋白相对表达量升高(P <0.05)。结论 ICA能够有效促进DPSCs增殖,提高DPSCs神经向分化能力。  相似文献   
70.
目的:分析慢性阻塞性肺疾病(COPD)患者外周血单个核细胞(PBMCs)白细胞分化抗原36(CD36)信使核糖核酸(mRNA)、血清载脂蛋白E(ApoE)水平对急性加重期发生的预测价值。方法:选取2021年6月-2022年5月在湖州市中心医院就诊的COPD患者96例,其中急性加重期COPD患者为AECOPD组(n=50),稳定期COPD患者为稳定组(n=46),选取健康人群40例为对照组。检测所有受试者血清炎性因子[肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-1β、C反应蛋白(CRP)]、ApoE、肺功能指标[第1秒用力呼气容积与用力肺活量的比值(FEV1/FVC)、第1秒用力呼气容积占预计值百分比(FEV1%pred)]和PBMCs中CD36 mRNA水平;分析COPD患者PBMCs中CD36 mRNA、血清ApoE水平与炎性因子、肺功能指标的相关性以及PBMCs中CD36 mRNA、血清ApoE对COPD患者急性加重期发生的预测价值。结果:对照组、稳定组、AECOPD组吸烟史比例、TNF-α、IL-6、IL-1β、CRP、PBMCs中CD36 mRNA和血清ApoE水平依次升高,FEV1/FVC、FEV1%pred水平依次降低(P<0.05);COPD患者PBMCs中CD36 mRNA与血清ApoE水平呈正相关(P<0.05),COPD患者PBMCs中CD36 mRNA、血清ApoE水平均与血清TNF-α、IL-6、IL-1β、CRP呈正相关(P<0.05),与FEV1/FVC、FEV1%pred呈负相关(P<0.05);PBMCs中CD36 mRNA单独、血清ApoE单独、二者联合预测COPD患者急性加重期发生的曲线下面积(AUC)分别为0.887、0.871、0.966,二者联合预测的AUC高于CD36 mRNA、ApoE单独预测的AUC(P<0.05)。结论:COPD患者PBMCs中CD36 mRNA和血清ApoE均呈高表达,二者对COPD患者急性加重期发生具有一定的预测价值。  相似文献   
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