首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   213篇
  免费   12篇
儿科学   40篇
妇产科学   17篇
基础医学   25篇
临床医学   12篇
内科学   36篇
皮肤病学   3篇
神经病学   19篇
特种医学   13篇
外科学   27篇
综合类   2篇
预防医学   10篇
眼科学   1篇
药学   6篇
肿瘤学   14篇
  2024年   1篇
  2023年   1篇
  2022年   5篇
  2021年   4篇
  2020年   2篇
  2019年   1篇
  2018年   5篇
  2017年   3篇
  2016年   6篇
  2015年   11篇
  2014年   4篇
  2013年   8篇
  2012年   12篇
  2011年   16篇
  2010年   6篇
  2009年   5篇
  2008年   6篇
  2007年   11篇
  2006年   7篇
  2005年   6篇
  2004年   7篇
  2003年   12篇
  2002年   7篇
  2001年   3篇
  2000年   5篇
  1999年   7篇
  1998年   10篇
  1997年   4篇
  1996年   2篇
  1993年   1篇
  1992年   4篇
  1991年   6篇
  1990年   6篇
  1989年   5篇
  1988年   1篇
  1987年   5篇
  1986年   1篇
  1985年   2篇
  1984年   4篇
  1983年   2篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1976年   3篇
  1974年   1篇
  1971年   1篇
  1970年   2篇
排序方式: 共有225条查询结果,搜索用时 641 毫秒
1.
During a 16 month period, seven patients were admitted to our trauma center with "blow-in" fractures of the orbital roof. This injury results from a significant direct blunt force applied to the supraorbital region of the frontal bone with transmission of energy to the thin orbital plate of this bone and displacement of bone fragments downward into the superior orbit. High resolution CT with multiplanar reformation and three-dimensional display proved very useful in identifying and characterizing the bone and soft tissue abnormalities found in our patients. Our experience suggests that CT demonstration of supraorbital frontal bone fractures and/or frontal lobe cerebral contusions is an indication for thin section CT of the entire orbit, even when there is no evidence of a superior orbital rim fracture. Demonstration of an orbital blow-in fracture should prompt careful clinical assessment of the globe, optic nerve, and extraocular muscles to identify and appropriately manage underlying injuries to these structures.  相似文献   
2.
We evaluated polymorphonuclear leucocyte (PMN) chemotaxis and cortisol levels in cord blood from 15 healthy term infants delivered by caesarean section and from 15 healthy vaginally delivered term infants. Mean neutrophil chemotaxis was significantly higher in infants delivered by caesarean section (78.3±23.4m) than in vaginally delivered infants (57.8±16.6 m;P=0.01). Mean blood cortisol level was significantly lower in infants delivered by caesarean section (9.14±2.76 g/dl) than in infants born by vaginal delivery (20.71±6.98 g/dl;P=0.0001). No relationship was found between PMN chemotaxis and blood cortisol level. The higher neutrophil chemotactic activity observed in infants delivered by caesarean section could be related to general maternal anaesthesia.  相似文献   
3.
Introduction. Recently, the identification of the SEN virus as a possible etiological agent of parental transmission hepatitis led to the study of the prevalence of such pathogen agents, particularly SENV-H, in our population. This paper compares the rate prevalence in high-risk subjects, such as dialysis patients, and low-risk subjects, such as blood donors. Material and Methods. The study was carried out on SEN virus DNA extracted from serum of dialysis patients and blood donors, and the presence of viral genomes was performed by the nested PCR method. Results. The results showed a higher prevalence in male blood donors, supporting the hypothesis of an epidemiological role for sexual and also parental transmission, as is clearly demonstrated by the high prevalence in dialysis patients. The result reduced the importance of the possible etiological role of the SEN virus due to the high percentage of positivity in healthy population, and it induces one to consider poorly significant the pathogenicity of such viral agents. Conclusion. For this instance, the authors, in agreement with the phylogenically related TT virus, described SEN viruses as absolutely not pathogens and considered them as “simple guests.”  相似文献   
4.
5.
High mobility group box ‐1 (HMGB1) represents a common causal agent for various types of diseases, including infective pathologies. This study aimed to investigate the role of HMGB1 in β‐thalassemia major (TM) by evaluating its diagnostic and prognostic role. Fifty‐one TM patients and 30 healthy subjects (HS) were enrolled. Receiver operating characteristics (ROC) analysis was employed to calculate the area under the curve (AUC) for HMGB1 to determine the best cut‐off values capable of identifying infectious episodes. Adjusted risk estimates for infective events were calculated using univariate followed by multivariate Cox proportional hazard regression analysis. Serum HMGB1 levels were higher in TM patients than in HS (14·6 ± 8·7 vs. 2·08 ± 0·9 ng/ml, P < 0·0001). Patients who underwent splenectomy were characterized by lower levels of HMGB1, when compared with patients with an intact spleen (10·2 ± 8 vs. 19·1 ± 7 ng/ml, P = 0·004). ROC analyses revealed an AUC for serum HMGB1 of 0·801, with a sensitivity and specificity of 92·3% and 68·2% to detect an infectious episode. Low HMGB1 levels predicted high risk of infective events (HR: 0·81; P = 0·006). HMGB1 represents a prognostic marker for TM patients and a predictive factor for infectious events.  相似文献   
6.
OBJECTIVES: To provide epidemiological data about psychological and sexual functioning during menopausal transition in a large Italian non-clinical sample, and to investigate their correlation with life events. METHODS: The study design was a cross-sectional postal survey of a menopausal sample of women recruited from the General Registry Office in Ferrara's province. The sample was composed of four thousand and seventy-three women; they were sent a questionnaire designed on the basis of the Women's Health Questionnaire (WHQ). Together with the WHQ, the subjects filled out a personal file to define social status, cultural level, family's characteristics, recent menstrual cycles, gynaecological history and operations, drug assumption, life events in the last year, and lifetime depression. RESULTS: One thousand three hundred and forty-five women provided usable questionnaires. Factor analysis resulted in eight clusters: somatic symptoms, depressive symptoms, depressed mood with anxiety symptoms, cognitive difficulties, anxiety, sexual functioning, vasomotor symptoms and sleep problems. Mood and sexual function were impaired through the menopausal transition, with depressive and sexual symptoms being higher in the post-menopausal group compared to the pre-menopausal one. Therefore, the correlation between the two was greater in the pre- and peri-menopausal period. CONCLUSION: Depressive and sexual symptoms presented greater severity in the post-menopausal group. Both clusters of symptoms were strongly associated with life events. The parallel course of the two clusters could be related with a common pathoplastic action of life events, both on sexual symptoms and on depressive symptoms, occurring right at the time that a woman has to face the transition into menopause.  相似文献   
7.
Introduction

Single-shot devices have been developed to simplify pulmonary vein isolation (PVI). Randomized studies of the second-generation cryoballoon (CB 2nd) demonstrated excellent results. There are limited data comparing results of circular pulmonary vein ablation catheter (PVAC) with conventional RF ablation or CB for PVI.

Objective

Using a sequential registry cohort and a prospective randomized study, we aimed to compare the acute and long-term results of CB 2nd and PVAC Gold.

Methods

In the registry, consecutive patients with paroxysmal atrial fibrillation (AF) undergoing their first PVI were included. The preferred method used was PVAC Gold in 2014 and CB 2nd in 2015. Subsequently, a randomized study (PVAC vs. CB 2nd) was performed. Ablation success was measured as freedom of AF or atrial tachycardias (AT) off antiarrhythmic drugs.

Results

In the registry cohort, PVAC Gold was used in 60 patients and CB 2nd in 56 patients (age 66?±?11 years, 52% male, LAD 43?±?6). In the randomized study, 20 patients were treated with PVAC Gold and 22 with CB 2nd (age 67?±?9; 43% men, LAD 40?±?7 mm). During a mean follow up of 13.2?±?3.6 months, success was 54% in PVAC Gold patients and 81% in CB 2nd cases (p?=?0.001). In the randomized study 12 months success was 50% versus 86%, p?<?0.05. Complications occurred rare in both groups.

Conclusions

Our registry data and the randomized study both suggest superiority of PVI using CB 2nd as compared with PVI using PVAC Gold.

  相似文献   
8.
Surgical excision followed by histopathological examination is the gold standard for melanoma screening. However, the color-based inspection of hematoxylin-and-eosin-stained biopsies does not provide a space-resolved quantification of the melanin content in melanocytic lesions. We propose a non-destructive photo-thermal imaging method capable of characterizing the microscopic distribution and absolute concentration of melanin pigments in excised melanoma biopsies. By exploiting the photo-thermal effect primed by melanin absorption of visible laser light we obtain label-free super-resolution far-infrared thermal images of tissue sections where melanin is spatially mapped at sub-diffraction 40-μm resolution. Based on the finite-element simulation of the full 3D heat transfer model, we are able to convert temperature maps into quantitative images of the melanin molar concentration on B16 murine melanoma biopsies, with 4·10-4 M concentration sensitivity. Being readily applicable to human melanoma biopsies in combination with hematoxylin-and-eosin staining, the proposed approach could complement traditional histopathology in the characterization of pigmented lesions ex-vivo.  相似文献   
9.
The intermediate state between normal glucose tolerance and overt type 2 diabetes mellitus is associated with micro- and macrovascular diseases, requiring safe and cost-effective treatment measures interventions. A novel source of LC n-3 FAs is Calanus finmarchicus Oil, which showed promising effects on glucose homeostasis in preclinical studies due to anti-obesity effects and/or anti-inflammatory properties. In total, 43 obese patients (BMI: 31.7 ± 5.2 kg/m2) were allocated in the following two groups: (1) Calanus oil group (2 g CO/day) and (2) placebo group (2 g paraffin oil/day). Markers of glucose metabolism, body composition and energy intake were measured at the beginning (t0), after 12 weeks (t12) and 16 weeks (t16). Overall, parameters reflecting abnormal glucose homeostasis and insulin resistance in the liver, including fasting insulin (−2.9 mU/L ± 4.10, p < 0.05), HOMA-IR (−0.9 ± 1.28, p < 0.05) and hepatic insulin resistance index (−1.06 ± 1.72 × 106, p < 0.05) significantly enhanced after a 12-week CO-intervention, while no differences were observed in HbA1c, AUC0–2h Glucose, AUC0–2h Insulin, 2 h plasma glucose and muscle insulin sensitivity index. Our results indicate that Calanus oil causes beneficial effects on glucose metabolism and insulin resistance in obese patients, with clinical relevance to be verified in further studies. In addition, the possible active compounds and their mechanisms of action should be elucidated.  相似文献   
10.
Skin necrosis is the most severe complication arising from hyaluronic acid (HA) injection. To avoid skin necrosis, hyaluronidase should be injected along the course of the involved artery, to allow blood flow restoration. We evaluated the ability of hyaluronidase to degrade a HA filler in two simulated clinical situations—a compression case and an embolization case—to identify differences in the hyaluronidase injection. In the compression case, a bolus of HA filler was directly soaked in hyaluronidase solution; in the embolization case, a vein harvested from a living patient was filled with the same HA filler and then soaked in hyaluronidase. We then evaluated the quantity of HA remaining after 2 hr. While we found hydrolysis of HA in both cases, in the compression case, we detected almost complete hydrolysis, whereas in the embolization case we observed a reduction of the 60%. Our results support the hypothesis that vessel compression can be resolved with only one injection of hyaluronidase, while in the case of vascular embolization, repeated perivascular injections should be performed owing to the reduction of hyaluronidase activity.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号