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71.

Background

This large osteology study examined the reliability, reproducibility and correlation between previously described tibial tray rotation alignment lines (including Akagi and Dalury lines). In addition, it described a novel inter-eminence line utilising the tibial plateau inter-condylar eminences as a landmark.

Methods

A total of 214 post-medieval (18–19th centuries) skeletal tibia were examined. The inter/intra-observer variation and correlation between reference lines were measured.

Results

Inter-observer reproducibility was excellent and there were no differences between Akagi, Dalury, and inter-eminence lines. Similarly, intra-observer reliability was excellent for Akagi, Dalury, and inter-eminence lines. Qualitative review of tibial inter-condylar eminences suggested that these could be easily identifiable. When taking the medial angle from a medial–lateral reference line, the Akagi line showed a mean of 96.90° (± 10.27), inter-eminence line 94.52° (± 12.84), and Dalury line 88.06° (± 11.75). The angle produced by the Dalury line was significantly different from both the Akagi and inter-eminence lines (P  0.001). The Akagi line and inter-eminence line showed a strong correlation (r = 0.74). The Dalury line showed a weaker correlation with both the Akagi line (r = 0.69) and inter-eminence line (r = 0.40).

Conclusion

This study suggested that tibial rotation lines showed excellent intra/inter-observer reliability and reproducibility. The novel and easily drawn inter-eminence line showed strong correlation with the Akagi line and could be used for tibial tray rotational alignment in total knee arthroplasty.  相似文献   
72.
Cronobacter sakazakii is an opportunistic pathogen that causes neonatal meningitis and necrotizing enterocolitis. Its interaction with intestinal epithelium is important in the pathogenesis of enteric infections. In this study, we investigated the involvement of the inv gene in the virulence of C. sakazakii ATCC 29544 in vitro and in vivo. Sequence analysis of C. sakazakii ATCC 29544 inv revealed that it is different from other C. sakazakii isolates. In various cell culture models, an Δinv deletion mutant showed significantly lowered invasion efficiency, which was restored upon genetic complementation. Studying invasion potentials using tight-junction-disrupted Caco-2 cells suggested that the inv gene product mediates basolateral invasion of C. sakazakii ATCC 29544. In addition, comparison of invasion potentials of double mutant (ΔompA Δinv) and single mutants (ΔompA and Δinv) provided evidence for an additive effect of the two putative outer membrane proteins. Finally, the importance of inv and the additive effect of putative Inv and OmpA were also proven in an in vivo rat pup model. This report is the first to demonstrate two proteins working synergistically in vitro, as well as in vivo in C. sakazakii pathogenesis.  相似文献   
73.
ObjectiveWe explored the germline mutation spectrum and prevalence among 1650 women with breast and uterine cancer (BUC) who underwent multi-gene hereditary cancer panel testing at a single commercial laboratory.MethodsThe combined frequency of mutations in 23 BC and/or UC genes was compared between BUC cases and control groups with (1) no personal cancer history; (2) BC only; and (3) UC only using logistic regression.ResultsFourteen percent (n = 231) of BUC cases tested positive for mutations in BC and/or UC genes and were significantly more likely to test positive than individuals with BC only (P < 0.001), UC only (P < 0.01), or unaffected controls (P < 0.001). Analysis of gene-specific mutation frequencies revealed that MSH6, CHEK2, BRCA1, BRCA2, ATM, PMS2, PALB2 and MSH2 were most frequently mutated among BUC cases. Compared to BC only, BRCA1, MLH1, MSH2, MSH6, PMS2 and PTEN mutations were more frequent among BUC; however, only ATM mutations were more frequent among BUC compared to UC only. All of the more commonly mutated genes have published management guidelines to guide clinical care. Of patients with a single mutation in a gene with established testing criteria (n = 152), only 81.6% met their respective criteria, and 65.8% met criteria for multiple syndromes.ConclusionsWomen with BUC are more likely to carry hereditary cancer gene mutations than women with breast or uterine cancer alone, potentially warranting expanded genetic testing for these women. Most mutations found via multi-gene panel testing in women with BUC have accompanying published management guidelines and significant implications for clinical care.  相似文献   
74.
Objective: Redistribution of cardiac output is responsible for the “brain sparing” effect seen during periods of acute or chronic fetal stress. We investigated the relationship between prelabour cardiac function in fetuses that subsequently developed intrapartum fetal compromise (IFC).

Methods: A blinded, prospective, observational, cohort study, at Mater Mother’s Hospital, Brisbane, Australia. A cohort of 284 women with uncomplicated singleton pregnancies underwent ultrasound every 2 weeks from 36 weeks until delivery. Fetal cardiac output was assessed by conventional Doppler ultrasound and myocardial deformation was measured using velocity vector imaging.

Results: Two hundred and seventy three women were included in the final analysis, of which 19% had an emergency operative delivery for intrapartum fetal compromise (IFC). Global left ventricular strain (?12.1%, interquartile ranges (IQR)???10.3 to ?14% versus 13%, IQR ?11.3 to ?14.2%, p?=?.01) and strain rate (?1.00, IQR 0.85–1.16?s?1 versus ?1.11, IQR ?1.00 to ?1.21?s?1, p??1 versus 1.13?±?0.22?s?1, p?p?p?Conclusion: Lower global left ventricular strain and strain rate and cardiac output are associated with IFC and poorer condition of the newborn. Assessment of fetal cardiac function may be useful for risk stratification for intrapartum fetal compromise in apparently “low risk” term pregnancies.  相似文献   
75.
76.
77.
The occurrence of graft rejection episodes after orthotopic liver transplantation (OLT) despite the use of immunosuppressive drugs designed to suppress T lymphocyte functions, indicates the involvement of other types of cells in this process. The activity of natural killer cells and their killer immunoglobulin-like receptors (KIR) is regulated by human leukocyte antigen (HLA) class I determinants; C and Bw epitopes. Because recipient/donor pairs are usually HLA mismatched, recipient natural killer alloreactivity may be the mediating factor in rejection. In this retrospective study, we have analyzed rejection occurrence and outcome in 66 OLT recipients, 42 with and 24 without C or Bw epitope disparity in the rejection direction. Recipients transplanted from donors with no C epitope disparity had significantly fewer rejection episodes in the first year after transplantation compared with recipients transplanted across C epitope disparity (p = 0.0002). Moreover, this effect was more pronounced when the outcome was analyzed in OLT recipients across negative crossmatching for the anti-HLA class I and II antibodies. In contrast, Bw epitope disparity did not affect the outcome. In conclusion, C epitopes disparity between recipients and donors in the rejection direction appears to influence posttransplant liver outcome. This finding may be helpful in the choice of appropriate liver donor and planning immune suppression.  相似文献   
78.
79.

Introduction

Dietary control of classic phenylketonuria (PKU) needs restriction of natural proteins; adequate protein intake is achieved by adding low phenylalanine (phe) formulae. The adequacy of this diet for normal bone mineralization had not been sufficiently evaluated. Our aim was to evaluate and follow up bone mineral density (BMD) in children and adolescents with PKU within a 2-year time interval to assess the adequacy of a phenylalanine restricted diet for bone mineralization and to search for a possible relationship between BMD, dietary control and blood phenylalanine (phe) concentrations.

Material and methods

Thirty-two patients with classic PKU (3-19 years) were evaluated for their bone mineral status using dual energy X-ray absorptiometry (DEXA) both at the beginning (baseline) and the end (follow-up) of the study.

Results

Low BMD was detected in 31.25% at the start and in 6.25% of patients after 2 years follows-up. No relationship was found between BMD and the duration of diet compliance and phe level as well.

Conclusions

In this study the low BMD detected in our patients was both at baseline and follow-up independent of diet restriction. A yearly DEXA would be highly beneficial for early detection and treatment, thus preventing osteoporosis and decreasing the risk of fractures. We also suggest the importance of searching for new emerging therapies such as enzyme substitution or gene therapy as low protein diet compliance was not enough to maintain normal bone mineral density.  相似文献   
80.

Purpose

Polycystic ovary syndrome (PCOS) is associated with oxidative stress (OS) and serum superoxide dismutase (SOD) activity has been reported with mixed results. The objective of this study was to examine the activity of SOD both in the serum and FF from women with PCOS undergoing ICSI, as well as the expression of Cu/Zn-SOD mRNA in the cells recovered from the FF.

Methods

Forty women undergoing an ICSI trial were divided into: group I, included 20 PCOS cases, group II included 20 age-matched controls with tubal factor infertility. Both groups were similarly stimulated. A total of 204 metaphase II (MII) oocytes were aspirated; (108) from PCOS, and (96) from the control group. SOD activities in the serum and FF, as well as Cu/Zn-SOD (SOD1) mRNAs in follicular fluid (FF) cells were analyzed.

Results

There was a statistically highly significant decrease (p < 0.001) both in the mean serum SOD (45.56 ± 18.06) and FF SOD activity (42.49 ± 11.46) in PCOS than the control group (77.38 ± 7.82), (74.37 ± 6.15) respectively. The mean relative levels of Cu, Zn SOD mRNAs was significantly lower (p < 0.001) in cells isolated from the FF in PCOS (0.36 ± 0.14) than the control group (0.81 ± 0.15). SOD activity in FF had no effects on fertilization rate (p > 0.05), or embryo quality after intracytoplasmic sperm injection (ICSI).

Conclusion

Although decreased SOD activity in FF has no effect on fertilization rate and/or embryo quality, serum SOD activity could be a clinical parameter for determining systemic oxidative stress in PCOS.  相似文献   
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