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1.
AIMS: To evaluate the currently available evidence for the effectiveness of bisphosphonates in children with low bone mineral density (BMD) and fragility fractures associated with juvenile idiopathic arthritis (JIA), and the safety of bisphosphonates in JIA and other conditions. METHODS: Literature databases were searched using a structured search strategy. The effectiveness review included any studies of children with JIA treated with bisphosphonates. The safety review also included studies of osteogenesis imperfecta. Quantitative data analysis was not undertaken because of the heterogeneity of the studies; findings were summarised using tables and narrative synthesis. RESULTS: Ninety four studies were identified. Sixteen studies (78 JIA children) were included in the effectiveness review: one randomised controlled trial, three controlled cohort studies, 11 case series, and one case report. At baseline, children had low BMD below the expected values for age and sex matched children. In all studies, treatment with bisphosphonates increased BMD compared with baseline: the mean percentage increase in spine BMD ranged from 4.5% to 19.1%. Overall, studies were heterogeneous and of variable quality. A total of 59 papers were included in the safety review; treatment durations were up to three years. The most common side effect was a flu-like reaction with intravenous treatment. This occurred during the first infusion and was transient; the symptoms were managed with paracetamol and did not occur during subsequent cycles. CONCLUSIONS: Bisphosphonates are a promising treatment for low BMD and fragility fractures in children with JIA. However, the quality of the current evidence is variable and better studies are needed to more clearly assess their role.  相似文献   
2.
目的:观察非程控降温、-80℃冻存的方法对自体外周血十细胞(APBSC)的保存效果。方法:以6%羟乙基淀粉(HES)、5%二甲基亚砜(DMSO)及4%人血白蛋白(ALB)的混合物为冷冻防护剂,将APBSC直接置于-80℃下保存,冻存前反复苏后测定APBSC的CFU-GM、BFU-E;观察移植后造血功能重建情况。结果:13例患者白细胞在十3~+7天下降至(0.0~0.1)×10/L,白细胞(0.0~0.2)×109/L持续时间3~6天,于+9~+11天恢复至1.0X109/L以上.中性粒细胞绝对值(ANC)于+9~+11天达到0.5X109/L。血小板在+3~+7天下降至(2.0~21)×109/L,于+8~+15天恢复至20×109/L以上。CFU-GM、BFU-E回大率分别为76.5%、78.4%。结论:非程控降温、-80℃冻存是一简便、经济、有效的自体外周血于细胞保存方法。  相似文献   
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4.
Two human parathyroid hormone-related protein (hPTHrP) fragments were tested for effects on maternofetal transfer of 45Ca and Mg across the in-situ perfused rat placenta at 21 days of gestation (term = 23 days). The fetal placental circulation was perfused with a Mg-free Krebs-Ringer solution and the unidirectional maternofetal clearance (Kmf) of 45Ca and Mg compared with that of 51Cr-EDTA, the latter being employed as a paracellular diffusional marker. Placental perfusion with hPTHrP(1-34) (100 ng/ml) or hPTHrP(75-86)amide (50 ng/ml) did not significantly alter the Kmf of 45Ca or that of Mg. In separate rats, however, hPTHrP(1-34) but not hPTHrP(75-86)amide stimulated marked placental cyclic AMP (cAMP) release, the peak response of 63 +/- 7 pmol/min occurring 10 min after the beginning of the peptide perfusion. A lower dose of hPTHrP(1-34) (4 ng/ml) produced a similar peak release of cAMP, as did [Nle8,21, Tyr34]-rPTH(1-34)amide (4 ng/ml) and the adenylate cyclase agonist forskolin (17 mumol/l). Forskolin also rapidly increased the Kmf of 45Ca but not that of Mg or 51Cr-EDTA. The present study indicates that hPTHrP does not acutely affect maternofetal transfer of Ca or Mg across the perfused rat placenta. The data also question the role played by cAMP in the stimulatory actions of forskolin on placental Ca transport.  相似文献   
5.
A survey of bacteria contamination of hospital staff apparel in use in Anambra State, Nigeria, was carried out to determine the extent of contamination by clinically important bacteria. Of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. The potentially pathogenic bacteria isolated were Salmonella spp, Proteus vulgaris, Shigella dysenteriae, Pseudomonas aeruginosa and Staphylococcus aureus. The isolation of clinically important bacteria from the apparel suggests the need for improved infection control measures.  相似文献   
6.
The effect of nutritional status on the morbidity and mortality of major gastrointestinal surgery for benign disease was studied in 32 patients. Malnutrition was defined as a serum albumin less than 3.5 g/dl and a recent weight loss greater than 10%, in addition to any two of the following: weight for height, midarm circumference or triceps skin-fold thickness less than 10th percentile. The morbidity and mortality in the 17 malnourished patients was 59% and 29%, respectively, compared with 20% and 7% in 15 well-nourished patients matched for age and operative procedure (p less than 0.05). After operation, the mean duration of inadequate oral nutritional intake period (IONIP, defined as a caloric intake greater than 60% requirement) was 11.9 days +/- 2.9 (SEM) in well-nourished patients compared with 30.5 days +/- 3.7 in the malnourished group. The longer IONIP in malnourished patients was a consequence of the higher morbidity in this group, thus warranting the consideration of supportive (postoperative) parenteral nutrition in malnourished patients who undergo major gastrointestinal surgery for benign disease.  相似文献   
7.
目的:研究大鼠急性肺栓塞模型肺组织中衰老标记蛋白质30(SMP-30)的表达变化及其对Fas诱导的细胞凋亡的影响。方法:建立大鼠急性肺栓塞模型,分别在急性肺栓塞后1、8、24和48 h进行支气管肺泡灌洗,然后开胸取出肺组织。常规提取肺组织的总RNA和总蛋白,以正常组为对照,采取半定量RT-PCR的方法研究SMP-30在mRNA水平表达的变化;采用Western blotting方法进一步验证SMP-30在蛋白水平表达的变化;采用免疫组织化学方法检测大鼠肺组织中SMP-30以及肺泡巨噬细胞中IL-8在肺栓塞前后表达的变化及其组织分布情况;采用TUNEL法研究急性肺栓塞后组织细胞的凋亡情况;最后采用ELISA法检测急性肺栓塞后肺泡灌洗液中sFasL的浓度变化。结果:在大鼠急性肺栓塞后的不同时点,SMP-30的mRNA水平和蛋白水平均逐渐降低,在24和48 h下降最为明显。免疫组化研究表明SMP-30主要分布在支气管黏膜上皮细胞和肺泡上皮细胞,急性肺栓塞后SMP-30在上述细胞内的表达均明显降低。TUNEL染色发现随着SMP-30表达的降低,肺组织内出现明显的细胞凋亡现象,同时肺泡灌洗液中sFasL的浓度升高,肺泡巨噬细胞内IL-8的表达也明显升高。结论:大鼠急性肺栓塞后肺组织内SMP-30的表达明显降低,可能促进Fas-FasL细胞凋亡系统的活化。  相似文献   
8.
Generalized arterial calcification of infancy (GACI) is a rare disorder caused by ENPP1 or ABCC6 variants. GACI is characterized by low pyrophosphate, arterial calcification, and high mortality during the first year of life, but the natural course and possible differences between the causative genes remain unknown. In all, 247 individual records for patients with GACI (from birth to 58.3 years of age) across 19 countries were reviewed. Overall mortality was 54.7% (13.4% in utero or stillborn), with a 50.4% probability of death before the age of 6 months (critical period). Contrary to previous publications, we found that bisphosphonate treatment had no survival benefit based on a start-time matched analysis and inconclusive results when initiated within 2 weeks of birth. Despite a similar prevalence of GACI phenotypes between ENPP1 and ABCC6 deficiencies, including arterial calcification (77.2% and 89.5%, respectively), organ calcification (65.8% and 84.2%, respectively), and cardiovascular complications (58.4% and 78.9%, respectively), mortality was higher for ENPP1 versus ABCC6 variants (40.5% versus 10.5%, respectively; p = 0.0157). Higher prevalence of rickets was reported in 70.8% of surviving affected individuals with ENPP1 compared with that of ABCC6 (11.8%; p = 0.0001). Eleven affected individuals presenting with rickets and without a GACI diagnosis, termed autosomal recessive hypophosphatemic rickets type 2 (ARHR2), all had confirmed ENPP1 variants. Approximately 70% of these patients demonstrated evidence of ectopic calcification or complications similar to those seen in individuals with GACI, which shows that ARHR2 is not a distinct condition from GACI but represents part of the spectrum of ENPP1 deficiency. Overall, this study identified an early mortality risk in GACI patients despite attempts to treat with bisphosphonates, high prevalence of rickets almost exclusive to ENPP1 deficiency, and a spectrum of heterogenous calcification and multiple organ complications with both ENPP1 and ABCC6 variants, which suggests an overlapping pathology. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by US Government employees and their work is in the public domain in the USA.  相似文献   
9.
Trimethylaminuria (fish odour syndrome) is diagnosed from an increase in urinary excretion of trimethylamine with decreased trimethylamine oxide. We report a new quantitative stable isotope dilution gas chromatography-mass spectrometry procedure for the analysis of these metabolites using solid-phase microextraction (SPME). Both polydimethylsiloxane and mixed Carboxen-polydimethylsiloxane SPME fibres were found to be suitable for the headspace extraction of TMA. This new sampling technique could have wide application for the analysis of volatile and semi-volatile compounds by metabolic screening laboratories.  相似文献   
10.
目的检测哮喘患者外周血中IL-4及其变异体IL-4δ2的表达,探讨其在哮喘发病机制中的作用。方法采用半定量RT-PCR技术,检测10例哮喘患者IL-4及其变异体的表达,并与正常健康人群进行比较。结果哮喘患者IL-4表达较健康人群高,而且IL-4和IL-4δ2的比值远远高于健康人。结论IL-4和IL-4δ2表达的相对性可能在哮喘发病机制中具有重要作用,其可能是Th2细胞在不同临床疾病中功能多样性的原因之一。  相似文献   
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