首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2546篇
  免费   190篇
  国内免费   18篇
耳鼻咽喉   23篇
儿科学   62篇
妇产科学   87篇
基础医学   395篇
口腔科学   63篇
临床医学   299篇
内科学   554篇
皮肤病学   88篇
神经病学   237篇
特种医学   57篇
外科学   223篇
综合类   7篇
一般理论   2篇
预防医学   230篇
眼科学   11篇
药学   155篇
中国医学   2篇
肿瘤学   259篇
  2024年   4篇
  2023年   40篇
  2022年   59篇
  2021年   113篇
  2020年   75篇
  2019年   87篇
  2018年   117篇
  2017年   89篇
  2016年   96篇
  2015年   97篇
  2014年   115篇
  2013年   153篇
  2012年   204篇
  2011年   187篇
  2010年   114篇
  2009年   105篇
  2008年   141篇
  2007年   161篇
  2006年   141篇
  2005年   149篇
  2004年   124篇
  2003年   100篇
  2002年   70篇
  2001年   24篇
  2000年   17篇
  1999年   17篇
  1998年   24篇
  1997年   19篇
  1996年   8篇
  1995年   17篇
  1994年   22篇
  1993年   7篇
  1992年   9篇
  1991年   6篇
  1990年   8篇
  1989年   4篇
  1988年   3篇
  1986年   3篇
  1985年   5篇
  1984年   6篇
  1983年   1篇
  1982年   2篇
  1981年   2篇
  1980年   1篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1974年   2篇
  1967年   1篇
  1963年   1篇
排序方式: 共有2754条查询结果,搜索用时 15 毫秒
81.

Background

Moderately and late preterm infants represent a considerable and increasing proportion of infants cared for in neonatal departments worldwide. Parents of preterm infants are at risk of postpartal depression (PPD) and posttraumatic stress disorder (PTSD), and preterm infants are at risk of developmental impairment.

Aim

This study aimed to assess (1) the incidence of parental PPD and PTSD in moderate to late preterm infants in comparison to full-term infants and (2) the influence of infants' motor repertoire assessed by Prechtl's general movements and illness severity on parental PPD and PTSD.

Subjects

We studied 60 mothers and 56 fathers of 69 preterm infants (born at 32 to 37 weeks of gestation) and 32 mothers and 29 fathers of 34 full-term infants.

Outcome measures

We assessed the incidence of parental PPD, PTSD and perceived social support as well as infants' illness severity and motor repertoire at birth, term and 3 months corrected age.

Results

Preterm mothers and fathers had significant higher depression scores after birth compared to full-term parents (p = 0.033 and 0.021). Preterm fathers also had higher traumatization scores compared to full-term fathers (p = 0.007). Probable or possible PPD/PTSD was not associated with infant's illness severity or quality of motor repertoire. No differences in motor development were found between preterm and full-term infants.

Conclusion

Moderate to late preterm infants' parents are at increased risk for PPD irrespective of infants' motor repertoire or illness severity.  相似文献   
82.
83.
84.
Objective. To analyze whether the intestinal mucosa in rheumatoid arthritis (RA) is immnunologically abnormal and whether sulfasalazine (SSZ) possesses any local intestinal immunoregulatory effect. Methods. Lymphocyte subpopulations and HLA—DR expression were evaluated in biopsy specimens from the duodenal—jejunal mucosa and in peripheral blood samples obtained from 17 patients with RA, both before and after 16 weeks of SSZ treatment. The same mucosal assays were also performed in 7 controls. Results. The mucosa of the small intestine in RA patients showed no differences in morphology, HLA—DR expression, or the amounts and distribution of CD3+, CD4+, CD8+, and γ/δ+ lymphocytes compared with the control group. However, there was a reduction in mucosal CD3+ and γ/δ+ lymphocyte numbers after SSZ therapy, which did not correspond to a change in peripheral blood CD3+ lymphocyte number. SSZ treatment also tended to diminish the peripheral blood CD4+:CD8+ cell ratio (P = 0.05). Conclusion. No signs of inflammation or immunologic abnormalities were seen in RA duodenal-jejunal mucosa. In this part of the intestine, however, SSZ exerted immunoregulatory effects that were not encountered in the peripheral blood.  相似文献   
85.
MALT1 is a key mediator of NF-κB signaling and a main driver of B-cell lymphomas. Remarkably, MALT1 is expressed in the majority of pancreatic ductal adenocarcinomas (PDACs) as well, but absent from normal exocrine pancreatic tissue. Following, MALT1 shows off to be a specific target in cancer cells of PDAC without affecting regular pancreatic cells. Therefore, we studied the impact of pharmacological MALT1 inhibition in pancreatic cancer and showed promising effects on tumor progression. Mepazine (Mep), a phenothiazine derivative, is a known potent MALT1 inhibitor. Newly, we described that biperiden (Bip) is a potent MALT1 inhibitor with even less pharmacological side effects. Thus, Bip is a promising drug leading to reduced proliferation and increased apoptosis in PDAC cells in vitro and in vivo. By compromising MALT1 activity, nuclear translocation of c-Rel is prevented. c-Rel is critical for NF-κB-dependent inhibition of apoptosis. Hence, off-label use of Bip or Mep represents a promising new therapeutic approach to PDAC treatment. Regularly, the Anticholinergicum Bip is used to treat neurological side effects of Phenothiazines, like extrapyramidal symptoms.  相似文献   
86.
Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system.  相似文献   
87.
88.
89.
Medulloblastomas are malignant embryonal brain tumours that may harbour mutations in histone‐modifying genes, while mutations in histone genes have not been detected to date. We here describe the first SHH medulloblastoma with H3 K27M mutation. This may have diagnostic implications as H3 K27M mutations are the hallmark of diffuse midline gliomas, H3 K27M mutant, WHO grade IV. Medulloblastomas arise in midline structures and thus must not be mistaken for DMG when using an antibody detecting the H3 K27M mutation.  相似文献   
90.
Cardiac allograft vasculopathy (CAV) causes heart failure after heart transplantation (HTx), but its pathogenesis is incompletely understood. Notch signaling, possibly modulated by everolimus (EVR), is essential for processes involved in CAV. We hypothesized that circulating Notch ligands would be dysregulated after HTx. We studied circulating delta‐like Notch ligand 1 (DLL1) and periostin (POSTN) and CAV in de novo HTx recipients (n = 70) randomized to standard or EVR‐based, calcineurin inhibitor‐free immunosuppression and in maintenance HTx recipients (n = 41). Compared to healthy controls, plasma DLL1 and POSTN were elevated in de novo (P < .01; P < .001) and maintenance HTx recipients (P < .001; P < .01). Use of EVR was associated with a treatment effect for DLL1. For de novo HTx recipients, a change in DLL1 correlated with a change in CAV at 1 (P = .021) and 3 years (P = .005). In vitro, activation of T cells increased DLL1 secretion, attenuated by EVR. In vitro data suggest that also endothelial cells and vascular smooth muscle cells (VSMCs) could contribute to circulating DLL1. Immunostaining of myocardial specimens showed colocalization of DLL1 with T cells, endothelial cells, and VSMCs. Our findings suggest a role of DLL1 in CAV progression, and that the beneficial effect of EVR on CAV could reflect a suppressive effect on DLL1. Trial registration numbers— SCHEDULE trial: ClinicalTrials.gov NCT01266148; NOCTET trial: ClinicalTrials.gov NCT00377962.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号