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61.

Aim

To analyze women's advancement compared with that of men and to determine whether advancement in hierarchical status differs from advancement in the professional recognition achieved by women from 1996 to 2008.

Methods

A retrospective study was carried in Hospital Clínic in Barcelona. We analyzed data on temporary and permanent positions, hierarchy, promotions, specialty, age, and sex among the participants.

Results

The female-to male ratio among trainee medical specialists was higher than 1 throughout the study period. After completion of specialist training, the proportion of women with temporary contracts more than doubled that of men. Less than 50% of women achieved permanent positions compared with 70% of men. For permanent non-hierarchical and hierarchical positions, the female-to-male ratio gradually decreased from 0.5 to below 0.2. Although more than 50% of trainee specialists were women, the number of female consultants remained 25% lower than that of men. In 2008, the final year of the study, the percentage of women who had achieved the grade of senior consultant was one-third that of men (29.5% of men vs 10.9% of women; p < 0.0001).

Conclusions

The significant differences in medical positions held by men and women illustrate the ‘leaky pipeline phenomenon’, consisting of a disproportionately low number of women achieving leading medical positions. The full potential of the increasing number of women physicians will not be reached without continuing efforts to improve the hospital medicine environment.  相似文献   
62.
Although transplantation of adipose-derived stem cells (ADSC) in chronic myocardial infarction (MI) models is associated with functional improvement, its therapeutic value is limited due to poor long-term cell engraftment and survival. Thus, the objective of this study was to examine whether transplantation of collagen patches seeded with ADSC could enhance cell engraftment and improve cardiac function in models of chronic MI. With that purpose, chronically infarcted Sprague–Dawley rats (n = 58) were divided into four groups and transplanted with media, collagen scaffold (CS), rat ADSC, or CS seeded with rat ADSC (CS-rADSC). Cell engraftment, histological changes, and cardiac function were assessed 4 months after transplantation. In addition, Göttingen minipigs (n = 18) were subjected to MI and then transplanted 2 months later with CS or CS seeded with autologous minipig ADSC (CS-pADSC). Functional and histological assessments were performed 3 months post-transplantation. Transplantation of CS-rADSC was associated with increased cell engraftment, significant improvement in cardiac function, myocardial remodeling, and revascularization. Moreover, transplantation of CS-pADSC in the pre-clinical swine model improved cardiac function and was associated with decreased fibrosis and increased vasculogenesis. In summary, transplantation of CS-ADSC resulted in enhanced cell engraftment and was associated with a significant improvement in cardiac function and myocardial remodeling.  相似文献   
63.
64.
The synthesis of terpolymers can lead to very interesting combinations of monomers, which can affect the solubility of the polymer, its thermal stability or resistance in saline aqueous media. Free-radical inverse microemulsion and solution polymerization techniques were used to prepare water-soluble acrylamide-N-vinylpyrrolidone-(vinylbenzyl)trimethylammonium chloride terpolymers. The formulation of the polymerizable microemulsion was optimized by using the screening of surfactant percentage and HLB concept. The influence of synthesis temperature on the terpolymer composition and molecular weight was investigated. The reactions were carried out at 60, 70, and 75 °C for the microemulsion technique and at 40, 50, and 55 °C for the solution polymerization technique. The reaction products from both processes were water-soluble polymers, and the two techniques reached high conversions and molecular masses. Maximal molecular weights were displayed by terpolymers prepared by the solution method at 40 °C (959, 840 g mol−1) and the inverse microemulsion method at 60 °C (795, 994 g mol−1). According to NMR analysis, the highest amount of (vinylbenzyl) trimethylammonium chloride was incorporated into the terpolymer structure by the inverse microemulsion method. In contrast, the solution method yielded higher contents of acrylamide and N-vinylpyrrolidone. The viscosity properties of the terpolymers in aqueous solutions were directly correlated to their molecular weight and synthesis conditions.

Terpolymers based on acrylamide, N-vinylpyrrolidone and (vinylbenzyl)trimethylammonium chloride (VBTA) were synthesized using inverse microemulsion and solution methods. The microemulsion promoted the incorporation of VBTA in the terpolymer structure.  相似文献   
65.
Targeted sequencing (TS) is growing as a screening methodology used in research and medical genetics to identify genomic alterations causing human diseases. In general, a list of possible genomic variants is derived from mapped reads through a variant calling step. This processing step is usually based on variant coverage, although it may be affected by several factors. Therefore, undercovered relevant clinical variants may not be reported, affecting pathology diagnosis or treatment. Thus, a prior quality control of the experiment is critical to determine variant detection accuracy and to avoid erroneous medical conclusions. There are several quality control tools, but they are focused on issues related to whole‐genome sequencing. However, in TS, quality control should assess experiment, gene, and genomic region performances based on achieved coverages. Here, we propose TarSeqQC R package for quality control in TS experiments. The tool is freely available at Bioconductor repository. TarSeqQC was used to analyze two datasets; low‐performance primer pools and features were detected, enhancing the quality of experiment results. Read count profiles were also explored, showing TarSeqQC's effectiveness as an exploration tool. Our proposal may be a valuable bioinformatic tool for routinely TS experiments in both research and medical genetics.  相似文献   
66.
67.
BackgroundHomologous recombination deficiency (HRD) is a phenotype that is characterized by the inability of a cell to effectively repair DNA double-strand breaks using the homologous recombination repair (HRR) pathway. Loss-of-function genes involved in this pathway can sensitize tumors to poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors and platinum-based chemotherapy, which target the destruction of cancer cells by working in concert with HRD through synthetic lethality. However, to identify patients with these tumors, it is vital to understand how to best measure homologous repair (HR) status and to characterize the level of alignment in these measurements across different diagnostic platforms. A key current challenge is that there is no standardized method to define, measure, and report HR status using diagnostics in the clinical setting.MethodsFriends of Cancer Research convened a consortium of project partners from key healthcare sectors to address concerns about the lack of consistency in the way HRD is defined and methods for measuring HR status.ResultsThis publication provides findings from the group’s discussions that identified opportunities to align the definition of HRD and the parameters that contribute to the determination of HR status. The consortium proposed recommendations and best practices to benefit the broader cancer community.ConclusionOverall, this publication provides additional perspectives for scientist, physician, laboratory, and patient communities to contextualize the definition of HRD and various platforms that are used to measure HRD in tumors.  相似文献   
68.
69.
Aortic valve replacement with pulmonary autograft was first performed by Donald Ross in 1967. Initially, the procedure was not widely accepted, by Cardiologists and Cardiac surgeons fundamentally due to its complexity and demanding surgical technique, and because innumerous series two cardiac valves were at risk. The results published in the last 10-15 years established the pulmonary autograft as one of the best methods of aortic valve replacement, especially in pediatric patients and young adults. In the present article, we reviewed present indications and contraindications, and our clinical experience with 26 patients (pediatrics and adults). Analysis of the first 22 the patients with a minimum of 6 months of follow-up (180-620 days) was performed. Follow-up is complete (100%). Mean age was 31.4 +/- 12.6 years. Five patients were pediatrics (<= 14 years). Three patients (11%) with previous percutaneous procedures and 4 patients (14%) with previous surgical procedures. There was no early or late mortality. In the last follow-up, 19 of 22 (86.36%) had no autograft insufficiency (>= grade 1), and in one patient it was moderate (grade 2). The 2 remaining patients developed severe autograft insufficiency (grade 4) and were reoperated on, with satisfactory postoperative outcome. Mean maximal gradient was 7.85 +/- 5 mmHg at 18 months (3-29). Patients with preoperative aortic stenosis showed a significant reduction in myocardial mass index (208.7 +/- 32 a 95.8 +/- 28.8 g/m2) at 18 months. In these patients, septal and posterior wall thickness decreased significantly, in the first month. Two pediatric patients have developed transpulmonar gradient > 50 mmHg. One of them underwent successful stent implantation. We have not observed significant homograft insufficiency in any of our patients. All our patients remain asymptomatic (functional class I) without medical treatment. We have not observed either thromboembolic or haemorrhagic episodes, nor endocarditis. No patient is receiving anticoagulants. Clinical and echocardiographic mid term results in pulmonary autograft and homograft in our series, are excellent after the Ross procedure.  相似文献   
70.
Escherichia coli heat‐labile enterotoxin (LT) exhibits a broad range of immunomodulatory activities, including the induction of lymphocyte‐programmed cell death. In previous studies, we have demonstrated that in vivo LT promotes apoptosis of immature T and B cells through the stimulation of endogenous glucocorticoids. In the present study, we show that the extrinsic cell‐death pathway as well as the apoptosis‐inducing factor do not participate in the LT‐induced elimination of thymocytes. In contrast to developing lymphocytes, LT promotes the death of mature lymphocytes by both glucocorticoid‐ and Fas death receptor/Fas ligand‐dependent mechanisms. However, the dependency of these mechanisms in the LT‐induced cell‐death activity seems to be different among CD4+ and CD8+ T cells. Altogether, our study shows that the same bacterial toxin can induce apoptosis of lymphoid cells through several mechanisms depending on the status of differentiation of these cells.  相似文献   
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