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71.
为探讨可溶性白细胞介素-2受体(solubleinterleukin2receptor,SIL-2R)在变应性鼻炎中的作用机理,采用双抗体夹心酶联免疫吸附测定(ELISA)法测定39例变应性鼻炎患者、19例慢性鼻炎患者和15例健康人血清及鼻分泌物SIL-2R水平。结果发现变应性鼻炎患者血清SIL-2R水平高于慢性鼻炎患者及健康人(P<0.001)。提示SIL-2R在变应性鼻炎的发病中起重要作用  相似文献   
72.
The aim of this study was to use a new system of realistic voxel phantoms, based on computed tomography scanning of humans, to assess its ability to specify the internal dosimetry of selected human examples in comparison with the well-established MIRD system of mathematical anthropomorphic phantoms. Differences in specific absorbed fractions between the two systems were inferred by using organ dose estimates as the end point for comparison. A "family" of voxel phantoms, comprising an 8-week-old baby, a 7-year-old child and a 38-year-old adult, was used and a close match to these was made by interpolating between organ doses estimated for pairs of the series of six MIRD phantoms. Using both systems, doses were calculated for up to 22 organs for four radiopharmaceuticals with widely differing biodistribution and emission characteristics (technetium-99m pertechnetate, administered without thyroid blocking; iodine-123 iodide; indium-111 antimyosin; oxygen-15 water). Organ dose estimates under the MIRD system were derived using the software MIRDOSE 3, which incorporates specific absorbed fraction (SAF) values for the MIRD phantom series. The voxel system uses software based on the same dose calculation formula in conjunction with SAF values determined by Monte Carlo analysis at the GSF of the three voxel phantoms. Effective doses were also compared. Substantial differences in organ weights were observed between the two systems, 18% differing by more than a factor of 2. Out of a total of 238 organ dose comparisons, 5% differed by more than a factor of 2 between the systems; these included some doses to walls of the GI tract, a significant result in relation to their high tissue weighting factors. Some of the largest differences in dose were associated with organs of lower significance in terms of radiosensitivity (e.g. thymus). In this small series, voxel organ doses tended to exceed MIRD values, on average, and a 10% difference was significant when all 238 organ doses were considered as a single group. In 12 comparisons of effective dose, the mean voxel to MIRD ratio was 1.07 (range 0.72-1.32). It was shown for the majority of cases that, whereas some large differences in SAF values exist, differences in source organ and effective dose values between the MIRD and voxel methods were largely accounted for by the respective organ mass differences. The reasons for various organ dose differences with the selected radiopharmaceuticals are discussed. Taking biological variation into account, there is reasonable agreement between the two methods but some significant differences exist that warrant further investigation. More extensive comparisons involving a wide variety of voxel phantoms are required to establish whether realistic voxel phantoms should eventually replace the MIRD system.  相似文献   
73.
目的:为临床外科寻找简便易行有效的预防腹腔术后粘连的新方法和药物:方法:用白及、黄芪等多味中药制成抗粘灵气雾剂,通过对60只家免盲肠部分切除制造实验动物模型,并对其创面进行活体药物喷涂。结果:抗粘灵气雾剂预防腹腔术后粘连效果良好,总有效率86.67%,与对照组比较,有非常显著差异(P〈0.01)。结论:抗粘灵气雾剂预防腹腔术后粘连有效,且方法简便易行,从而可为临床外科领域提供高效。价廉的木申抗粘连药物。  相似文献   
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75.
Helicobacter pylori infection of the human stomach is the most important risk factor for development of gastric cancer. Whereas persistent viral infection leads to a number of cancers, H. pylori was the first bacteria linked to a human cancer. The exact mechanisms that lead to cancer induction are not clear, but study of the bacterial factors important for colonization and the host responses to the infection are starting to yield important clues.  相似文献   
76.
An uncontrolled study with process evaluation was conducted in three U.K. community maternity sites to establish the feasibility and acceptability of delivering a novel breastfeeding peer‐support intervention informed by motivational interviewing (MI; Mam‐Kind). Peer‐supporters were trained to deliver the Mam‐Kind intervention that provided intensive one‐to‐one peer‐support, including (a) antenatal contact, (b) face‐to‐face contact within 48 hr of birth, (c) proactive (peer‐supporter led) alternate day contact for 2 weeks after birth, and (d) mother‐led contact for a further 6 weeks. Peer‐supporters completed structured diaries and audio‐recorded face‐to‐face sessions with mothers. Semistructured interviews were conducted with a purposive sample of mothers, health professionals, and all peer‐supporters. Interview data were analysed thematically to assess intervention acceptability. Audio‐recorded peer‐support sessions were assessed for intervention fidelity and the use of MI techniques, using the MITI 4.2 tool. Eight peer‐supporters delivered the Mam‐Kind intervention to 70 mothers in three National Health Service maternity services. Qualitative interviews with mothers (n = 28), peer‐supporters (n = 8), and health professionals (n = 12) indicated that the intervention was acceptable, and health professionals felt it could be integrated with existing services. There was high fidelity to intervention content; 93% of intervention objectives were met during sessions. However, peer‐supporters reported difficulties in adapting from an expert‐by‐experience role to a collaborative role. We have established the feasibility and acceptability of providing breastfeeding peer‐support using a MI‐informed approach. Refinement of the intervention is needed to further develop peer‐supporters' skills in providing mother‐centred support. The refined intervention should be tested for effectiveness in a randomised controlled trial.  相似文献   
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79.
目的通过对误诊为特发性血小板减少性紫癜(ITP)的再生障碍性贫血(再障)患儿临床特点和误诊原因的分析,提高临床医师对儿童再障的认识,减少早期误诊。方法收集我院1992年1月-2010年8月收治的曾误诊为ITP、入院后确诊为再障的20例患儿的临床资料,分别按照实验室检查、疗效及误诊原因进行回顾性分析。结果在所有再障患儿中,误诊为ITP者占16%,在被诊断为ITP时:(1)多数患儿已经出现明显的外周血二系或三系下降,而并非单纯血小板减少。(2)5例患儿行骨髓检查,但结果并不符合ITP骨髓象。(3)绝大部分患儿未进行必要的血小板抗体检查,或检查结果并不典型。(4)按ITP进行糖皮质激素和大剂量免疫球蛋白治疗,疗效欠佳,未能进一步检查以核实诊断。(5)所有患儿均不符合ITP诊断标准,经过进一步检查均符合再障诊断标准。经抗胸腺细胞免疫球蛋白、环胞素A和雄性激素等治疗后,参照再障疗效标准,总有效率和显效率分别为75%和62%。结论再障和ITP均存在明显的血小板减少和出血倾向,ITP发病率明显高于再障,临床容易发生误诊。因此,临床上发现血小板降低,在考虑ITP诊断时,必须同时考虑可导致血小板减少的其他疾病的可能性,严格参照中华医学会制定的"再生障碍性贫血诊断标准"和"特发性血小板减少性紫癜诊断标准",以明确诊断和进行必要的鉴别诊断。  相似文献   
80.
AIM: To evaluate the effects of reduced glutathione (GSH) and niacin combination on protein oxidative stress, endoplasmic reticulum (ER) stress, glycation, and aggregation of the αβ crystalline in human lens epithelial (HLE) cells treated with high glucose levels. METHODS: HLE cells were cultured and exposed to 25 mmol/L glucose to promote high glucose conditions. Groups of cells were co-treated with three different combinations of dosages: 10 μmol/L GSH+25 μmol/L niacin (P1), 30 μmol/L GSH+25 μmol/L niacin (P2), and 100 μmol/L GSH+25 μmol/L niacin (P3). After 72h incubation, protein carbonyl content (PCC) and glucose reactive protein (GRP78) content were assessed using ELISA examinations. After two-week incubation, advanced glycation end products (AGEs) were also assessed and the expression of αβ crystalline was measured using Western blot examination. RESULTS: PCC and GRP78 levels in the co-treated groups were not significantly reduced compared to control (P>0.05). In contrast, there was a significant decrease of the AGEs levels in all groups co-treated with GSH and niacin when compared with the control group (P<0.05). In addition, the αβ crystalline expression increased after high dose glucose administration, but decreased in all groups co-treated with GSH and combinations of GSH and niacin. CONCLUSION: Combinations of GSH and niacin inhibit the aggregation of proteins and prevent glycation in hyperglycemic HLE cells. This study shows that this combination may play an active role in preventing diabetic cataract mainly from the AGEs pathway.  相似文献   
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