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71.
目的探讨动力髋螺钉(DHS)和锁定钢板内固定治疗股骨转子间骨折的临床疗效。方法将50例老年股骨转子间骨折患者根据随机数字表法分为锁定钢板组(25例)和DHS组(25例),比较两组切口长度、手术时间、术中出血量、术后引流量、住院时间、Barthel生活指数、骨折愈合时间、肢体短缩程度、疗效及术后并发症情况。结果两组患者术后均获随访,时间6~12个月。髋关节功能Harris评分:锁定钢板组优14例,良9例,可2例,差0例,优良率23/25;DHS组优9例,良13例,可2例,差1例,优良率22/25;两组比较差异无统计学意义(P0.05)。两组住院时间、Barthel生活指数、术后并发症情况比较差异无统计学意义(P0.05)。锁定钢板组患者在手术时间、切口长度、术中出血量、术后引流量、骨折愈合时间、肢体短缩程度方面与优于DHS组(P0.05)。结论 DHS和锁定钢板内固定治疗股骨转子间骨折均疗效显著,但锁定钢板内固定具有切口小、出血少、手术时间短等优点。  相似文献   
72.
Explosive blast injury has become the most prevalent injury in recent military conflicts and terrorist attacks. The magnitude of this kind of polytrauma is complex due to the basic physics of blast and the surrounding environments. Therefore, development of stable, reproducible and controllable animal model using an ideal blast simulation device is the key of blast injury research. The present review addresses the modeling of blast injury and applications of shock tubes.  相似文献   
73.
The clinical use of conventional ultrasonography (US) in autosomal dominant polycystic kidney disease (ADPKD) is currently limited by reduced diagnostic sensitivity, especially in at-risk subjects younger than 30 years of age. In this single-center prospective study, we compared the diagnostic performance of MRI with that of high-resolution (HR) US in 126 subjects ages 16–40 years born with a 50% risk of ADPKD who underwent both these renal imaging studies and comprehensive PKD1 and PKD2 mutation screening. Concurrently, 45 healthy control subjects without a family history of ADPKD completed the same imaging protocol. We analyzed 110 at-risk subjects whose disease status was unequivocally defined by molecular testing and 45 unaffected healthy control subjects. Using a total of >10 cysts as a test criterion in subjects younger than 30 years of age, we found that MRI provided both a sensitivity and specificity of 100%. Comparison of our results from HR US with those from a previous study of conventional US using the test criterion of a total of three or more cysts found a higher diagnostic sensitivity (approximately 97% versus approximately 82%) with a slightly decreased specificity (approximately 98% versus 100%) in this study. Similar results were obtained in test subjects between the ages of 30 and 40 years old. These results suggest that MRI is highly sensitive and specific for diagnosis of ADPKD. HR US has the potential to rival the diagnostic performance of MRI but is both center- and operator-dependent.  相似文献   
74.

Introduction

The objective of this study was to evaluate the changes of skeletal and dental structures in mild to moderate skeletal Class III children following the use of a new magnetic orthopedic appliance (MOA-III).

Methods

A total of 36 patients (14 boys and 22 girls, mean age 9 years and 5 months) who presented with a mild to moderate skeletal Class III jaw discrepancy were treated with MOA-III. Another group of 20 untreated patients (9 boys and 11 girls, mean age 9 years and 2 months) with the same level of deformity served as the control group. The average treatment time was 6.6 months. Radiographs were taken at the same time intervals for both groups. A paired t test was used to determine the significant differences before and after treatment, and a two-sample t test was used to analyze the differences between the treatment and control groups.

Results

The anterior crossbite in all subjects was corrected after MOA-III therapy. The maxillomandibular relationship showed favorable changes (ANB, Wits, overjet increased significantly, P < 0.001). The maxilla was anteriorly positioned (SNA, ptm-A, ptm-S increased significantly, P < 0.001) with clockwise rotation (PP-FH increased, P < 0.001). The mandible showed a slight downward and backward rotation (SNB decreased, P < 0.05, MP-SN, Y-axis increased, P < 0.05). The length of the mandibular body showed no significant changes (Go-Pg, P?>?0.05). Significant upper incisor proclination and lower incisor retroclination were observed (UI-NA increased, P < 0.001, LI-NB, FMIA decreased, P < 0.001). The upper lip moved forward, and the lower lip moved backward (UL-EP increased, P?<?0.001, LL-EP decreased, P?<?0.05). In the control group, most of the parameters showed normal growth, except for some unfavorable mandibular skeletal and soft tissue changes (Go-Pg, Go-Co, MP-SN, N′-SN-Pg′ increased, P < 0.001). Significant positive changes were induced with the MOA-III appliance compared to the untreated group.

Conclusions

The MOA-III was effective for the early treatment of a mild to moderate Class III malocclusion in children.
  相似文献   
75.
76.
Cross-frequency phase-amplitude coupling (PAC) in neuronal oscillations network plays an important functional role in large scale neuronal communication and neuronal encoding. In the present study, a novel approach named permutation mutual information (PMI) was applied in measuring PAC. It is derived from the permutation entropy based on the mutual information theory, by which the mutual information of permutations of two time series can be evaluated. In order to verify the ability of PMI, a numerical test was performed by using both simulation data and experimental data. The performances of PMI were compared with that of two well-known methods, which were the mean vector length (MVL) and the modulation index (MI). It was found that the performance of PMI was similar to that of MI when measuring PAC intensity, but the coupling sensitivity of PMI was the highest among all these three approaches. Moreover, there was the lowest sensitivity in the MVL measurement, suggesting that MVL was a more conservative approach in detecting the existence of PAC. In addition, an ROC analysis showed that PMI performed better in measuring PAC compared to that of others. Furthermore, the experimental data, obtained from rats’ hippocampal CA3 regions, were analyzed by using the three approaches. The result was essentially in line with that of the simulation performances. In a word, the results suggest that PMI is a better choice for assessing PAC under the certain conditions.  相似文献   
77.
BACKGROUND: Human umbilical cord mesenchymal stem cells (hUC-MSCs) have low immunogenicity and it is unclear whether insulin producing cells (IPCs) that differentiate from hUC-MSCs have low immunogenicity. OBJECTIVE: To investigate the immunogenicity of IPCs differentiating from hUC-MSCs in vitro and after IPCs transplantation into the host. METHODS: (1) The hUC-MSCs were induced to differentiate into IPCs according to the modified scheme. Flow cytometry assay was used to detect the immunophenotype and apoptotic rate of IPCs in a cytotoxicity test. (2) Cell counting kit-8 was used to detect the proliferative capacity of human peripheral blood mononuclear cells in the one-way mixed lymphocyte assay. (3) The IPCs were then transplanted into the abdominal cavity and left renal capsule of mice, and then the infiltration of immune cells was detected by flow cytometry and immunohistochemistry. RESULTS AND CONCLUSION: The IPCs highly expressed HLA-ABC and lowly expressed HLA-DR, CD40 and CD80. The apoptosis rate of IPCs increased with the increase of pre-sensitized splenocytes in the cytotoxicity test. In the one-way mixxd lymphocyte assay, IPCs inhibited the proliferation of human peripheral blood mononuclear cells when the target ratio was 10:1 and 50:1. After IPCs transplantation, the number of lymphocytts was increased in the transplanttd si. In summary, our results show that IPCs that differentiatt from hUC-MSCs maintain low immunogenicity in vitro, but have some immunogenicity after transplantation into the host due to microenvironment changes. © 2018, Journal of Clinical Rehabilitative Tissue Engineering Research. All rights reserved.  相似文献   
78.

Background

Trichothiodystrophy nonphotosensitive 1 (TTDN1) is a disease with mental retardation, brittle hair. Some cases of the diseases are caused by mutations of the MPLKIP gene.

Methods

We carefully identified the clinic characteristics, the sulfur level and pattern of the hair shafts of a female patient of with the symptom of hypergonadotropic hypogonadism, and of her parents and brother whose are healthy. We also collected the blood sample of the patient and performed the exon sequencing. One G insertion in MPLKIP was identified after analyzing the obtained exon sequencing profile. The G insertion sites in the patient, her parents and brother, were verified using Sanger sequencing. The G insertion in MPLKIP were compared to the dbSNP.

Results

The female patient of TTDN1 carries a homozygous G insertion (rs747470385) in the MPLKIP gene. The parents and brother of the patient are heterozygous carriers of the same mutation, but are healthy. The hair shafts of the patient had a tiger-tail pattern with relatively low sulfur levels. To the best of our knowledge, this is the first report that autosomal recessive inheritance of the G insertion in the MPLKIP gene results in TTDN1.

Conclusion

Our results indicate that the homozygotic G insertion in MPLKIP results in the TTDN1 with hypergonadotropic hypogonadism, while heterozygous carriers of the same mutation have no symptoms and healthy. These results provide novel insights into the association of mutations in MPLKIP and TTDN1 with hypergonadotropic hypogonadism.
  相似文献   
79.
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