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41.
Calcitriol deficiency and phosphate retention are two main factors in the pathogenesis of renal hyperparathyroidism. In spite of normal serum levels, phosphate may have an important role even in moderate RI. The aim of this study was to evaluate the effect of dietary phosphorus restriction on serum levels of calcitriol in patients with moderate RI. We studied 21 patients (7 F/14 M); mean age 61.7 +/- 15 years old; corrected creatinine clearance 51.4 +/- 14 ml/m. Serum PTH, calcitriol 25(OH)D3, calcium, phosphorus and urinary excretion of calcium and phosphorus were measured before and after 30 days on phosphorus restricted diet (700 mg/day). RESULTS: [table: see text] CONCLUSIONS: Our patients with moderate RI have elevated serum levels of PTH while calcitriol was in the lower normal range. Dietary phosphorus restriction resulted in a significant decrease in PTH levels and a significant increase in serum calcitriol concentrations. The levels of 25(OH)D3 did not change in this study.  相似文献   
42.

Introduction and objectives

Current therapeutic options for severe aortic stenosis (AS) include transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). Our aim was to describe the prognosis of patients with severe AS after the decision to perform an intervention, to study the variables influencing their prognosis, and to describe the determinants of waiting time > 2 months.

Methods

Subanalysis of the IDEAS (Influence of the Severe Aortic Stenosis Diagnosis) registry in patients indicated for TAVI or SAVR.

Results

Of 726 patients with severe AS diagnosed in January 2014, the decision to perform an intervention was made in 300, who were included in the present study. The mean age was 74.0 ± 9.7 years. A total of 258 (86.0%) underwent an intervention: 59 TAVI and 199 SAVR. At the end of the year, 42 patients (14.0%) with an indication for an intervention did not receive it, either because they remained on the waiting list (34 patients) or died while waiting for the procedure (8 patients). Of the patients who died while on the waiting list, half did so in the first 100 days. The mean waiting time was 2.9 ± 1.6 for TAVI and 3.5 ± 0.2 months for SAVR (P = .03). The independent predictors of mortality were male sex (HR, 2.6; 95%CI, 1.1-6.0), moderate-severe mitral regurgitation (HR, 2.6; 95%CI, 1.5-4.5), reduced mobility (HR, 4.6; 95%CI, 1.7-12.6), and nonintervention (HR, 2.3; 95%CI, 1.02-5.03).

Conclusions

Patients with severe aortic stenosis awaiting therapeutic procedures have a high mortality risk. Some clinical indicators predict a worse prognosis and suggest the need for early intervention.  相似文献   
43.

INTRODUCTION

Although diverticular disease of the colon is frequent, perforated diverticulitis causing subcutaneous emphysema is a uncommon entity. We wish to present this extremely rare case of perforated colonic diverticulum in the subcutaneous tissue, which is the first one that we have encountered in our practice, along with the accompanying diagnostic and therapeutic issues and a review of the literature.

PRESENTATION OF CASE

We report the case of an 83-year-old man who admitted to the emergency room due to an abdominal subcutaneous emphysema. Physical examination revealed a severe subcutaneous emphysema especially in the left iliac fossa and abdominal pain. An urgent contrast enhanced abdominal CT scan showed multiple diverticula in the sigmoid colon and multiple air bubbles in the subcutaneous tissue. The exploratory laparotomy identified a perforation of diverticular in subcutaneous tissue. Forty centimeters of colon were resected. The subcutaneous emphysema resolved without specific treatment. The postoperative period was uncomplicated.

DISCUSSION

Subcutaneous emphysema of anterior abdomen wall is an obvious physical sign but its etiology is complex to determine and may be potentially lethal. The pathophysiological mechanism involved is the emergence of a pressure gradient between the peritoneum and surrounding structures, causing rupture of the anterior abdominal wall, allowing gas from a perforation to diffuse along tissue planes.

CONCLUSION

This physical sign may be of especial value in elderly patient groups amongst whom perforation may be less clinically obvious. General surgeons should bear in mind this rare complication of colonic diverticulosis.  相似文献   
44.
45.
Nanoporous polymers are becoming increasingly interesting materials for electrochemical applications, as their large surface areas with redox-active sites allow efficient adsorption and diffusion of ions. However, their limited electrical conductivity remains a major obstacle in practical applications. The conventional approach that alleviates this problem is the hybridisation of the polymer with carbon-based additives, but this directly prevents the utilisation of the maximum capacity of the polymers. Here, we report a layer-by-layer fabrication technique where we separated the active (porous polymer, top) layer and the conductive (carbon, bottom) layer and used these “layered” electrodes in a supercapacitor (SC). Through this approach, direct contact with the electrolyte and polymer material is greatly enhanced. With extensive electrochemical characterisation techniques, we show that the layered electrodes allowed a significant contribution of fast faradic surface reactions to the overall capacitance. The electrochemical performance of the layered-electrode SC outperformed other reported porous polymer-based devices with a specific gravimetric capacitance of 388 F·g−1 and an outstanding energy density of 65 Wh·kg−1 at a current density of 0.4 A·g−1. The device also showed outstanding cyclability with 90% of capacitance retention after 5000 cycles at 1.6 A·g−1, comparable to the reported porous polymer-based SCs. Thus, the introduction of a layered electrode structure would pave the way for more effective utilisation of porous organic polymers in future energy storage/harvesting and sensing devices by exploiting their nanoporous architecture and limiting the negative effects of the carbon/binder matrix.  相似文献   
46.
47.
Pentraxin‐3 (PTX3), an acute‐phase protein released during inflammation, aids phagocytic clearance of pathogens and apoptotic cells, and plays diverse immunoregulatory roles in tissue injury. In neuroinflammatory diseases, like MS, resident microglia could become activated by endogenous agonists for Toll like receptors (TLRs). Previously we showed a strong TLR2‐mediated induction of PTX3 in cultured human microglia and macrophages by HspB5, which accumulates in glia during MS. Given the anti‐inflammatory effects of HspB5, we examined the contribution of PTX3 to these effects in MS and its animal model EAE. Our data indicate that TLR engagement effectively induces PTX3 expression in human microglia, and that such expression is readily detectable in MS lesions. Enhanced PTX3 expression is prominently expressed in microglia in preactive MS lesions, and in microglia/macrophages engaged in myelin phagocytosis in actively demyelinating lesions. Yet, we did not detect PTX3 in cerebrospinal fluid of MS patients. PTX3 expression is also elevated in spinal cords during chronic relapsing EAE in Biozzi ABH mice, but the EAE severity and time course in PTX3‐deficient mice did not differ from WT mice. Moreover, systemic PTX3 administration did not alter the disease onset or severity. Our findings reveal local functions of PTX3 during neuroinflammation in facilitating myelin phagocytosis, but do not point to a role for PTX3 in controlling the development of autoimmune neuroinflammation.  相似文献   
48.
IntroductionWithin the context of participatory action research (PAR) at an Intensive Care Unit (ICU), 4 proposals for change were agreed by consensus to improve the attention given to families of critical patients. One proposal was the creation of a guideline for attending to family members, inspired by the participants’ desire to improve the attention given to this group of users.Objectives1) To design a guide that would meet the needs of professionals and users. 2) To reach an agreement on the minimum requirements for attention given to families of critical patients.Materials and methodsQualitative methodology, based on PAR. For each of the initiatives, a working group was created, composed mainly of professionals from the ICU coordinated by a researcher. In the case of the guide, an online community was also created as a working tool to speed up communications among the participants, reducing the number of face-to-face sessions. Participation was voluntary. To draft the guideline, a Clinical Practice Guideline for support the family was made available, which had been translated into Spanish, together with an up-to-date bibliography.ResultsTwenty four professionals were involved. We developed a guide that contained the following sections: introduction, objectives, the experiences and needs of families of patients in the ICU, strategies for action, specific procedures, and hospital resources. We designed strategies for the diffusion and implementation of the guide.ConclusionsThe guide is a useful tool that offers the professionals greater assurances and unifying criteria for action. During subsequent stages of the PAR project, an assessment will be made of the impact on professionals and users.  相似文献   
49.
Abstract: Circadian rhythms disruptions, including abnormalities of circadian phase position and melatonin secretion, have been described in major depression (MD). Arylalkylamine N‐acetyltransferase (AANAT) is a key enzyme of the melatonin pathway involved in circadian oscillations of melatonin levels. We assessed the contribution of AANAT gene variability to susceptibility to MD considering common and rare genetic variations through a sequential sequencing and single nucleotide polymorphism (SNP)‐based genotyping approach in a sample of 445 unrelated patients with MD (257 unipolar MD, 188 bipolar depression) and 440 community‐based screened control subjects. We identified 17 sequence changes, thirteen of which represented novel sequence variations. We did not observe an over‐representation of patients carrying rare variants compared with the healthy controls. Common variants (MAF > 2%) were included in a case–control association analysis that showed significant association after multiple testing correction of two SNPs located in the promoter region of AANAT with MD: rs3760138 (P = 0.00006) and rs4238989 (P = 0.005). Multimarker analysis found significant associations between two three‐marker protective haplotypes and a susceptibility three‐marker haplotype containing the rare alleles of rs3760138‐rs4238989‐rs8150 and MD. We present evidence of the association of genetic variability in the AANAT gene with susceptibility to MD. Our results support the hypothesis that the melatonin‐signaling pathway and circadian clock mechanisms may contribute to the pathophysiology of MD.  相似文献   
50.
Malignancy is one of the comorbidities linked to golimumab, a biological TNF-α blocker. In this systematic review and meta-analysis, we searched different databases and analyzed original publications to elucidate the remaining open question about the real association of malignancies with golimumab therapy. The most frequent cancer in patients treated with golimumab, in association or not with methotrexate, is the lung adenocarcinoma. However, lymphoma is not very commonly represented in these patients. We show that there is no major and evident risk of malignancies associated with golimumab in current scientific literature. An increased risk of malignancies may be associated with golimumab, but this warrants further clinical confirmation. Also, this risk mentioned in different studies must be taken with caution because of number of limits and biases.  相似文献   
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