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991.

Backround

Calcifying epithelioma of Malherbe, or Pilomatricoma, is considered an uncommon cutaneous neoplasia, normally occurring in children as a solitary, firm, asymptomatic, hard, subcutaneous, slowly growing nodule on the face, neck, or proximal upper extremity. In literature, two Pilomatricoma ultrasound patterns are described: the totally calcified nodule and the hypoechoic nodule with internal calcific foci. High frequency ultrasound has not yet been applied for routine diagnosis of Pilomatricoma. The aim of the study was to retrospectively identify specific ultrasound features.

Methods

We retrieved 124 histologically Pilomatricoma cases: 28 patients with 32 lesions were preoperatively evaluated with ultrasound.

Results

22/32 have shown a solid formation, hypoechoic, with a sharp outline. Of these 22, 10 lesions were completely calcifying and 12 partially calcified. In 3/32 lesions with uncertain diagnosis, ultrasounds showed a complex/mixed pattern with pseudo-fluid areas and microspots. 7/32 lesions with US different diagnosis included 3 complex lesions, 2 cystic lesions and 2 solid nodular lesions.

Conclusion

In addition to well-known ultrasound patterns (completely calcified and partially calcified) we identified three new, not yet described, patterns that constitute the 31% of the cases: complex, pseudocistyc and pseudotumoral.  相似文献   
992.
The role of different factors in influencing the risk of seizures during multiple sclerosis (MS) is not known. To perform a systematic review and meta-analysis of risk factors for epilepsy during MS. Pubmed, Google scholar, and Scopus databases were searched. Articles published in English (1986–2016) were included. Nine studies were included (3 retrospective cohort and 6 case–control) enrolling 2845 MS patients (217 with epilepsy; 7.6%). MS patients with epilepsy had a younger age at onset compared to MS patients without seizures (difference in means = ?5.42 years, 95% CI ?7.19 to ?3.66, p < 0.001). Mean EDSS value at inclusion tended to be higher in patients with epilepsy, without reaching statistical significance (difference in means = 0.45, 95% CI ?0.01 to 0.91, p = 0.054). No differences were observed in sex distribution (OR = 0.94, 95% CI 0.51–1.72, p = 0.83) and clinical form (OR = 1.03, 95% CI 0.33–3.21, p = 0.96). Two studies evaluated presence and number of cortical lesions as a risk factor for epilepsy in MS using different MRI techniques: in one study, cortical lesions were more frequently observed in patients with epilepsy (OR = 7.06, 95% CI 2.39–20.8; p < 0.001). In the other, cortico-juxtacortical lesions were more frequently observed in patients with epilepsy (OR = 2.6, 95% CI 1.0–6.5; p = 0.047). Studies about risk factors for epilepsy during MS are heterogeneous. Compared to MS patients without seizures, patients with epilepsy have an earlier MS onset and a higher EDSS score after similar disease duration. Clinical form of MS and sex do not predict the appearance of seizures.  相似文献   
993.
In previous work, we demonstrated that NF‐κB p50 acts as crucial regulator of adult hippocampal neural progenitor cells (ahNPC). Indeed, NF‐κB p50 knockout (KO) mice are characterized by remarkably reduced hippocampal neurogenesis. As a follow up to that work, herein we show that when cultured in vitro, ahNPC from wild type (WT) and p50KO mice are not significantly different in their neurogenic potential. This observation prompted us to investigate cell‐autonomous and noncell‐autonomous consequences of p50 absence on neuronal fate specification of ahNPC. In particular, we focused our attention on astrocytes, known to provide soluble proneurogenic signals, and investigated the influence of WT and p50KO astrocyte conditioned media (ACM) on WT and p50KO ahNPC differentiation. Interestingly, while WT ACM promoted both neuronal and astroglial differentiations, p50KO ACM only supported astroglial differentiation of WT ahNPC. By using a LC–MS/MS approach, we identified some proteins, which are significantly upregulated in p50KO compared with WT astrocytes. Among them, lipocalin‐2 (LCN‐2) was recognized as a novel astroglial‐derived signal regulating neuronal fate specification of ahNPC. Interestingly, LCN‐2 proneurogenic effect was greatly reduced in p50KO NPC, where LCN‐2 receptor gene expression appeared downregulated. In addition to that, we demonstrated p50KO NPC unresponsiveness to both neuronal and astroglial fate specification signals from WT and p50KO ACM, and we identified a reduced expression of α2δ1, a thrombospondin‐1 receptor, as another phenotypic change occurring in ahNPC in the absence of p50. Altogether, our data suggest that dysregulated NPC‐astrocyte communication may contribute to a reduced hippocampal neurogenesis in p50KO mice in vivo. GLIA 2016 GLIA 2017;65:169–181  相似文献   
994.
The laboratory rat (Rattus norvegicus) is a key tool for the study of medicine and pharmacology for human health. A large database of phenotypes for integrated fields such as cardiovascular, neuroscience, and exercise physiology exists in the literature. However, the molecular characterization of the genetic loci that give rise to variation in these traits has proven to be difficult. Here we show how one obstacle to progress, the fine-mapping of quantitative trait loci (QTL), can be overcome by using an outbred population of rats. By use of a genetically heterogeneous stock of rats, we map a locus contributing to variation in a fear-related measure (two-way active avoidance in the shuttle box) to a region on chromosome 5 containing nine genes. By establishing a protocol measuring multiple phenotypes including immunology, neuroinflammation, and hematology, as well as cardiovascular, metabolic, and behavioral traits, we establish the rat HS as a new resource for the fine-mapping of QTLs contributing to variation in complex traits of biomedical relevance.  相似文献   
995.
Little is known about the clonal structure or stem cell architecture of the human small intestinal crypt/villus unit, or how mutations spread and become fixed. Using mitochondrial DNA (mtDNA) mutations as a marker of clonal expansion of stem cell progeny, we aimed to provide answers to these questions. Enzyme histochemistry (for cytochrome c oxidase and succinate dehydrogenase) was performed on frozen sections of normal human duodenum. Laser‐capture microdissected cells were taken from crypts/villi. The entire mitochondrial genome was amplified using a nested PCR protocol; sequencing identified mutations and immunohistochemistry demonstrated specific cell lineages. Cytochrome c oxidase‐deficient small bowel crypts were observed within all sections: negative crypts contained the same clonal mutation and all differentiated epithelial lineages were present, indicating a common stem cell origin. Mixed crypts were also detected, confirming the existence of multiple stem cells. We observed crypts where Paneth cells were positive but the rest of the crypt was deficient. We have demonstrated patches of deficient crypts that shared a common mutation, suggesting that they have divided by fission. We have shown that all cells within a small intestinal crypt are derived from one common stem cell. Partially‐mutated crypts revealed some novel features of Paneth cell biology, suggesting that either they are long‐lived or a committed Paneth cell‐specific long‐lived progenitor was present. We have demonstrated that mutations are fixed in the small bowel by fission and this has important implications for adenoma development. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
996.

Background and purpose:

Members of the calcin family, presently including imperatoxin A, maurocalcin, opicalcins and hemicalcin, are basic, 33-mer peptide activators of ryanodine receptors (RyRs), the calcium channels of the sarcoplasmic reticulum (SR) that provide the majority of calcium for muscle contraction. Here we describe hadrucalcin, a novel member of this family.

Experimental approach:

Hadrucalcin was isolated from the venom of Hadrurus gertschi. Amino acid sequence and mass were determined by Edman degradation and mass spectrometry respectively. A cDNA library was constructed to generate clones for DNA sequence determination. Biological activity of native toxin was confirmed with [3H]ryanodine binding, by using SR vesicles from cardiac and skeletal muscle, and with single skeletal (RyR1) and cardiac (RyR2) channels reconstituted in lipid bilayers. Hadrucalcin was applied to intact ventricular myocytes to investigate effects on calcium transients. The secondary structure of hadrucalcin was computer-modelled by using atomic coordinates from maurocalcin, a structurally similar peptide.

Key results:

Hadrucalcin is distinguished from previously described congeners by two additional amino acids in its primary sequence and the lack of prominent amphipathicity. Hadrucalcin activated RyRs with high affinity (EC50= 37 nmol·L−1), induced a long-lasting subconductance state on RyR1 and RyR2, and rapidly (lag time ∼2 s) penetrated ventricular cardiomyocytes, eliciting discharge of internal calcium stores and spontaneous contractions.

Conclusions and implications:

Hadrucalcin is a cell-permeant, powerful activator of RyRs, which has translational potential for targeted delivery of drugs to RyR as novel therapeutic intervention in arrhythmogenic disease.  相似文献   
997.
Background  Many techniques have excellent results at 2 years of follow-up but some matters regarding their long-term efficacy have arisen. This is why bariatric surgery results must be analyzed in long-term follow-up. The aim of this study was to extend the analysis over 5 years, evaluating weight loss, morbidity, and mortality of the surgical procedures performed. Methods  This was a retrospective cohort study of the different procedures for morbid obesity practiced in our Department of Surgery for morbid obesity. The results have been analyzed in terms of weight loss, morbidity improvement, and postoperative morbidity (Bariatric Analysis And Reporting Outcome System). Results  One hundred twenty-five patients were operated on open vertical banded gastroplasty (VBG), 150 patients of open biliopancreatic diversion (BPD) of Scopinaro, 100 patients of open modified BPD (common limb 75 cm; alimentary limb 225 cm), and 115 patients of laparoscopic Roux-en-Y gastric bypass (LRYGBP). Mean follow-up was: VBG 12 years, BPD 7 years, and LRYGBP 4 years. An excellent initial weight loss was observed at the end of the second year of follow-up in all techniques, but from this time an important regain of weight was observed in VBG group and a discrete weight regain in LRYGBP group. Only BPD groups kept excellent weight results so far in time. Mortality was: VBG 1.6%, BPD 1.2%, and LRYGBP 0%. Early postoperative complications were: VBG 25%, BPD 20.4%, and LRYGBP 20%. Late postoperative morbidity was: protein malnutrition 11% in Scopinaro BPD, 3% in Modified BPD group, and no cases reported either in VBG group or LRYGBP group; iron deficiency 20% VBG, 62% Scopinaro BPD, 40% modified BPD, and 30.5% LRYGBP. A 14.5% of VBG group required revision surgery to gastric bypass or to BPD due to 100% weight regain or vomiting. A 3.2% of Scopinaro BPD with severe protein malnutrition required revision surgery to lengthen common limb to 100 cm. A 0.8% of LRYGBP required revision surgery to distal LRYGBP (common limb 75 cm) due to 100% weight regain. Conclusions  The most complex bariatric procedures increase the effectiveness but unfortunately they also increase morbidity and mortality. LRYGBP is safe and effective for the treatment of morbid obesity. Modified BPD (75–225 cm) can be considered for the treatment of superobesity (body mass index > 50 kg/m2), and restrictive procedures such as VBG should only be performed in well-selected patients due to high rates of failure in long-term follow-up.  相似文献   
998.
MAP kinase-interacting kinase 1 and 2 (Mnk1 and Mnk2) are protein-serine/threonine kinases that are activated by ERK or p38 and phosphorylate eIF4E, which is involved in cap-dependent translation initiation. However, Mnk1/2 double knockout (Mnk-DKO) mice show normal cell growth and development despite an absence of eIF4E phosphorylation. Here we show that the tumorigenesis occurring in the Lck-Pten mouse model (referred to here as tPten−/− mice) can be suppressed by the loss of Mnk1/2. Phosphorylation of eIF4E was greatly enhanced in lymphomas of parental tPten−/− mice compared with lymphoid tissues of wild-type mice, but was totally absent in lymphomas of tPten−/−; Mnk-DKO mice. Notably, stable knockdown of Mnk1 in the human glioma cell line U87MG resulted in dramatically decreased tumor formation when these cells were injected into athymic nude mice. Our data demonstrate an oncogenic role for Mnk1/2 in tumor development, and highlight these molecules as potential anticancer drug targets that could be inactivated with minimal side effects.  相似文献   
999.
1000.
The methylphenidate transdermal system (MTS) provides a novel method of delivery for methylphenidate, a well-studied and effective medication for attention-deficit/hyperactivity disorder. The MTS achieves two major goals. First, the delivery system allows for administration throughout the day with a single patch, thus improving adherence. Second, it is the first approved attention-deficit/hyperactivity disorder medication that is not administered orally, thus bypassing gastrointestinal absorption and first-pass metabolism through the enteric circulation. In this article, we review the current data on MTS, including preclinical, clinical and post-marketing studies, and compare efficacy and tolerability to currently available treatments.  相似文献   
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