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61.
Suicide has been reported as the second or third most common cause of death in children and adolescents all over the world. The aim of the study was to investigate the general properties of suicide in childhood and adolescents, and to evaluate the results in the light of literature. Reports of autopsies performed between 2001 and 2005 in the Morgue Department of the Council of Forensic Medicine in Istanbul (n = 16853) were examined retrospectively. Deaths between 0–18 years of age doubtlessly considered as suicide were included in the study. Childhood and adolescent (0–18 years) deaths comprised 10.4% (n = 1761) of all medico-legal autopsy cases. 136 cases of suicidal origin were evaluated in terms of age, gender, and method of suicide. The ages ranged between 7 and 18, with a mean of 15.54 ± 2.691(SD). The most common method of suicide was hanging (59.2%) in both genders. Older adolescents (16–18 age group) constituted the overwhelming number (63.2%, n = 86) of all cases. Seven cases of 10 years of age and below were determined, and hanging was the method of suicide in five of these cases. In order to prevent childhood suicides, families and society should be aware of their responsibilities.  相似文献   
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IntroductionThis study aimed to evaluate the effect of manual strangulation of the uterine isthmus on the amount of blood loss during cesarean section.Material and methodsThis is a prospective randomized controlled trial. A total of 118 participants were enrolled in the study. Manual strangulation of the uterine isthmus just after placental removal was performed during cesarean section in group I (n = 57; the strangulation group). Strangulation was not performed in group II (n = 61; the control group). Preoperative and postoperative venous blood hemoglobin, capillary hemoglobin, and absorbed blood levels during the operation were compared between the two groups.ResultsThe median age of the patients was 28.5 (19–41). The median body mass index of the patients in the study was 27 (21–42). There were no significant differences in the demographic characteristics of the patients between the groups. The median difference between the preoperative and postoperative 4–6 h capillary hemoglobin values was significantly lower in the strangulation group (2.0 (0–9)) than in the control group (3.0 (0–8)). The amount of absorbed blood during the operation was also significantly lower in the strangulation group (164.5 ml (69–1310)) than in the control group (230 ml (35–3223)).ConclusionsManual uterine strangulation of the uterine isthmus immediately after the removal of the placenta may induce a 30% decrease in blood loss during cesarean section.  相似文献   
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OBJECTIVES: This study investigated the effect of silicon coating (SiO2) by magnetron sputtering on bond strength of two different titanium ceramics to titanium. METHODS: Sixty cast titanium specimens were prepared following the protocol ISO 9693. Titanium specimens were divided into two test and control groups with 15 specimens in each. Test groups were silicon coated by the magnetron sputtering technique. Two titanium ceramics (Triceram and Duceratin) were applied on both test (coated) and control (uncoated) metal specimens. The titanium-ceramic specimens were subjected to a three point flexural test. The groups were compared for their bond strength. SEM and SEM/EDS analyses were performed on the delaminated titanium surfaces to ascertain bond failure. RESULTS: The mean bond strength of Ti-Duceratin, Ti-Triceram, Si-coated Ti-Duceratin and Si-coated Ti-Triceram were 17.22+/-2.43, 23.31+/-3.18, 23.21+/-3.81 and 24.91+/-3.70 MPa, respectively. While the improvement in bond strength was 30% for Duceratin, it was statistically insignificant for Triceram. An adhesive mode of failure was observed in the Duceratin control group. In the silicoated Duceratin specimen, the bonded ceramic boundaries were wider but less than in the silicoated Triceram specimen. In the coated Triceram specimen, the ceramic retained areas were frequent and the failure mode was generally cohesive. SIGNIFICANCE: Silicon coating was significantly effective in both preventing titanium oxide layer formation and in improving bond strength for Duceratin. However, it was of less value for Triceram.  相似文献   
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Transgenic expression of activated AKT1 in the murine prostate induces prostatic intraepithelial neoplasia (PIN) that does not progress to invasive prostate cancer (CaP). In luminal epithelial cells of Akt-driven PIN, we show the concomitant induction of p27(Kip1) and senescence. Genetic ablation of p27(Kip1) led to downregulation of senescence markers and progression to cancer. In humans, p27(Kip1) and senescence markers were elevated in PIN not associated with CaP but were decreased or absent, respectively, in cancer-associated PIN and in CaP. Importantly, p27(Kip1) upregulation in mouse and human in situ lesions did not depend upon mTOR or Akt activation but was instead specifically associated with alterations in cell polarity, architecture, and adhesion molecules. These data suggest that a p27(Kip1)-driven checkpoint limits progression of PIN to CaP.  相似文献   
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OBJECTIVE: The objective of this study was to evaluate the effectiveness of inactivated influenza vaccine in preventing acute otitis media (AOM) and otitis media with effusion (OME) in children aged 6 to 60 months who attend day care. STUDY DESIGN: This prospective, single-blind study was conducted in 8 day care centers in Ankara, Turkey. One hundred nineteen (61 vaccinated and 58 unvaccinated against influenza) healthy children were examined at study entry and at 6-week intervals for 6 months by the same 2 otorhinolaryngologists who were blinded about the vaccination status of the children. The frequency of AOM and OME is compared between the 2 groups and the effect of influenza season on frequency of episodes was evaluated. Based on national influenza laboratory data, the influenza season was determined to be the period between December 15, 2003, and January 31, 2004. RESULT: The frequencies of AOM, OME and total otitis media episodes in vaccinated children were 2.3%, 22.8% and 25.2%, respectively, and these frequencies were 5.2%, 31.1% and 36.3% in the unvaccinated group. The difference was statistically significant (P < 0.01). This difference was especially prominent in the influenza season (P < 0.05). CONCLUSION: Influenza vaccine is effective in reducing AOM and OME episodes in 6- to 60-month-old day care children, especially during influenza season.  相似文献   
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BACKGROUND: Keratinocyte damage and lichenoid-interface reaction are the two major pathologic findings in lichen planus (LP). Matrix metalloproteinases (MMPs) are proteinases that participate in extracellular matrix (ECM) degradation and may play an important role in basal membrane (BM) damage in LP. Fibronectin (FN) mediates a variety of cellular interactions with ECM and plays important roles in cell adhesion, migration, growth and differentiation. OBJECTIVE: To determine MMP-2, MMP-3, MMP-9 and FN expressions in LP and discuss the possible associations. MATERIALS AND METHODS: Skin biopsy samples of 55 patients with LP and 11 normal skin were investigated. Five discoid lupus erythematosus (DLE) and 5 chronic dermatitis (CD) samples were also examined for comparison. Immunochemical stainings were performed for MMP-2, MMP-3, MMP-9 and fibronectin. RESULTS: Weak or absent expressions of MMP-2 and MMP-3 in epidermis; and dense MMP-9 expression in dermal inflammatory infiltrate cells were detected in LP. FN expression was lost in epidermal basal layer and papillary dermis. CONCLUSION: Loss of MMP-2, MMP-3 and FN in LP can be explained with the destruction of the epidermal basal layer. Similar expressions of MMP-2 and MMP-3 both in LP and DLE implied that these MMPs may be involved in the pathogenesis of interface dermatitis.  相似文献   
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