全文获取类型
收费全文 | 11545篇 |
免费 | 718篇 |
国内免费 | 56篇 |
专业分类
耳鼻咽喉 | 305篇 |
儿科学 | 288篇 |
妇产科学 | 312篇 |
基础医学 | 1655篇 |
口腔科学 | 439篇 |
临床医学 | 951篇 |
内科学 | 2657篇 |
皮肤病学 | 205篇 |
神经病学 | 1298篇 |
特种医学 | 256篇 |
外科学 | 1056篇 |
综合类 | 21篇 |
一般理论 | 5篇 |
预防医学 | 698篇 |
眼科学 | 132篇 |
药学 | 715篇 |
中国医学 | 41篇 |
肿瘤学 | 1285篇 |
出版年
2024年 | 20篇 |
2023年 | 116篇 |
2022年 | 281篇 |
2021年 | 433篇 |
2020年 | 276篇 |
2019年 | 326篇 |
2018年 | 358篇 |
2017年 | 301篇 |
2016年 | 362篇 |
2015年 | 389篇 |
2014年 | 520篇 |
2013年 | 627篇 |
2012年 | 959篇 |
2011年 | 1069篇 |
2010年 | 543篇 |
2009年 | 464篇 |
2008年 | 806篇 |
2007年 | 738篇 |
2006年 | 659篇 |
2005年 | 684篇 |
2004年 | 614篇 |
2003年 | 562篇 |
2002年 | 490篇 |
2001年 | 71篇 |
2000年 | 50篇 |
1999年 | 70篇 |
1998年 | 93篇 |
1997年 | 63篇 |
1996年 | 45篇 |
1995年 | 51篇 |
1994年 | 34篇 |
1993年 | 37篇 |
1992年 | 32篇 |
1991年 | 22篇 |
1990年 | 17篇 |
1989年 | 22篇 |
1988年 | 16篇 |
1987年 | 9篇 |
1986年 | 16篇 |
1985年 | 9篇 |
1984年 | 10篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1980年 | 7篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1976年 | 4篇 |
1973年 | 4篇 |
1970年 | 3篇 |
1969年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Famà F Gioffrè Florio MA Villari SA Caruso R Barresi V Mazzei S Pollicino A Scarfò P 《Chirurgia italiana》2007,59(4):499-506
Ectopic breast tissue occurs in 0.4-6% of the general population. Usually, these tissues develop along the embryonic milk line but other sites are reported in the literature. Accessory breasts are commonly axillary and may undergo hormonal changes. Some pathologies of normally positioned breasts can occur in ectopic breast tissue, including carcinoma, and therefore require traditional senological flow-charts and imaging strategies. Supernumerary nipples are generally asymptomatic but may sometimes be associated with urological malformations. In our 10-year experience, 208 patients were observed (138 polythelia and 70 polymastia) and 159 surgical procedures were performed, 97 for supernumerary nipple excision and 67 for accessory breast ablation. Five neoplastic lesions and 25 fibrocystic mastopathies were detected in specimens; normal nipple or breast tissue was found in 129. In view of the potentially malignant transformation of accessory breasts, thorough physician evaluation is needed. Surgery is currently suggested in cases of suspected malignancy, in symptomatic cases and for cosmetic problems. 相似文献
82.
Pierpaolo Sileri Vito Maria Stolfi Giampiero Palmieri Alessandra Mele Alessandro Falchetti Sara Di Carlo Achille Lucio Gaspari 《Journal of gastrointestinal surgery》2007,11(12):1662-1668
Stapled hemorrhoidopexy is widely accepted to treat hemorrhoids, but serious complications have been reported. In this prospective
audit, we correlated clinical outcome with pathological findings. From January 2003 to April 2007, 94 patients underwent hemorrhoidopexy.
Macroscopic appearance of the specimen (shape, size, and depth) was recorded. Microscopically, the presence of columnar, transitional,
and squamous epithelium, the involvement of circular/longitudinal smooth muscle, and features of mucosal prolapse were assessed.
Clinical outcome was evaluated by a validated questionnaire. Postoperative pain, secretion, and bleeding durations were 12.7 +/− 10.6,
5.6 +/− 9.6, and 6.3 +/− 8.4 days. Patient’s return to work averaged 16.7 +/− 10.7 days. Fissure, skin tags, and anal strictures
were observed in 23.4%. Seven patients experienced pain for a significantly longer period of time. All specimens contained
columnar mucosa, but 29.8% contained columnar and transitional epithelium and 12.8% contained columnar, anal transitional,
and stratified squamous epithelium. Smooth muscle was observed in 62.7%. Pain was significantly increased if transitional
epithelium was present in the specimen. No correlation or differences were observed if smooth muscle was present, although
postoperative bleeding was more frequent. Hemorrhoidopexy is safe and effective. The specimen should always be sent for pathology
examination. Only columnar epithelium should be present and, although the presence of smooth muscle does not influence the
outcome in terms of functional results, its presence may play a role in postoperative bleeding.
Presented as poster at the Digestive Disease Week, May 2007, Washington, USA 相似文献
83.
Raffaele Pascarella Michele Del Torto Rocco Politano Matteo Commessatti Rossana Fantasia Alessandra Maresca 《Injury》2014
Introduction
Bleeding associated with pelvic fracture mostly comes from the pre-sacral and lumbar venous plexus, or directly from the fracture site. Bleeding as a consequence of arterial lesion is less common (15–20%), and that resulting from lesion of the external iliac artery (EIA) is extremely rare. The mortality rate associated with iliac artery injury ranges from 38% to 72%. Total body CT-scan with contrast medium, angiography or packing can be performed when there is arterial injury. In some cases, embolisation can stop bleeding; however, when there is involvement of the aorta, common iliac artery or EIA, immediate surgery is mandatory. The aim of this study was to report our experience of pelvic fractures associated with EIA lesion.Materials and methods
Six patients with pelvic fracture and associated rupture of the EIA have been observed at our unit from 2004 to 2009. According to Tile classification there were three cases of type C and two cases of type B fracture. One case was a two-column acetabular fracture. Angiography was performed in all cases.Results
Three patients died on the day of trauma: two after angiography, and one after surgery of vascular repair. Three patients survived: two underwent a hemipelvectomy, and one underwent hip disarticulation.Discussion
Haemodynamic instability in patients with pelvic ring fracture is usually because of venous bleeding from the pre-sacral and lumbar plexus, or from the fracture site. Arterial injury is present in around 20% of cases. EIA lesions require immediate surgical treatment to restore blood flow. Depending on the type of injury, vascular surgery can be associated with pelvic fracture stabilisation.Conclusions
Pelvic ring fracture associated with an EIA lesion is extremely rare, with few cases reported in the literature. Angiography is used for diagnosis, and immediate surgical treatment is required to restore blood flow. Associated injuries and open fracture can lead to fatal complications or amputation. Rates of mortality and severe disability are extremely high. 相似文献84.
Paola Berchialla Ezio Nicola Gangemi Francesca Foltran Arber Haxhiaj Alessandra Buja Fulvio Lazzarato Maurizio Stella Dario Gregori 《International wound journal》2014,11(3):246-252
It is important for clinicians to understand which are the clinical signs, the patient characteristics and the procedures that are related with the occurrence of hypertrophic burn scars in order to carry out a possible prognostic assessment. Providing clinicians with an easy‐to‐ use tool for predicting the risk of pathological scars. A total of 703 patients with 2440 anatomical burn sites who were admitted to the Department of Plastic and Reconstructive Surgery, Burn Center of the Traumatological Hospital in Torino between January 1994 and May 2006 were included in the analysis. A Bayesian network (BN) model was implemented. The probability of developing a hypertrophic scar was evaluated on a number of scenarios. The error rate of the BN model was assessed internally and it was equal to 24·83%. While classical statistical method as logistic models can infer only which variables are related to the final outcome, the BN approach displays a set of relationships between the final outcome (scar type) and the explanatory covariates (patient's age and gender, burn surface area, full‐thickness burn surface area, burn anatomical area and wound‐healing time; burn treatment options such as advanced dressings, type of surgical approach, number of surgical procedures, type of skin graft, excision and coverage timing). A web‐based interface to handle the BN model was developed on the website www.pubchild.org (burns header). Clinicians who registered at the website could submit their data in order to get from the BN model the predicted probability of observing a pathological scar type. 相似文献
85.
Lehéricy S Biondi A Sourour N Vlaicu M du Montcel ST Cohen L Vivas E Capelle L Faillot T Casasco A Le Bihan D Marsault C 《Radiology》2002,223(3):672-682
PURPOSE: To determine whether the blood flow abnormalities frequently associated with arteriovenous malformations (AVMs) can alter functional magnetic resonance (MR) imaging evaluation of language lateralization and whether reorganization of language function occurs in patients with brain AVMs. MATERIALS AND METHODS: Eleven patients with left-hemisphere brain AVMs and 10 age-matched control subjects were examined with 1.5-T blood oxygen level-dependent (BOLD) functional MR imaging. Verbal fluency, sentence repetition, and story listening tasks were performed. The functional MR imaging laterality index in the frontal and temporal lobes was defined as the (L - R)/(L + R) ratio, where L and R are the numbers of activated pixels in the left and right hemispheres, respectively. Statistical analyses were performed with Wilcoxon signed rank, Fisher exact, and Kruskal-Wallis tests. RESULTS: Control subjects had left-sided language dominance, although symmetric pixel counts were observed in the frontal lobes in two subjects and in the temporal lobes in one subject. Six patients had left-sided language dominance similar to that observed in control subjects. Five of these patients had AVMs outside frontal or temporal language areas, without flow abnormalities. Five patients had abnormally right-sided asymmetric indexes (below mean control subject value - 2 SDs), which suggested language reorganization (P <.05). Results of Wada examination and/or postembolization functional MR imaging performed in two of these patients showed that the abnormal laterality indexes were at least partly due to severe flow abnormalities that impaired detection of BOLD MR imaging signal intensity. CONCLUSION: These data suggest that flow abnormalities may interfere with language lateralization assessment with functional MR imaging. 相似文献
86.
Two distinct types of depolarizing afterpotentials are differentially expressed in stellate and pyramidal‐like neurons of entorhinal‐cortex layer II 下载免费PDF全文
Two types of principal neurons, stellate cells and pyramidal‐like cells, are found in medial entorhinal‐cortex (mEC) layer II, and are believed to represent two distinct channels of information processing and transmission in the entorhinal cortex–hippocampus network. In this study, we found that depolarizing afterpotentials (DAPs) that follow single action potentials (APs) evoked from various levels of holding membrane voltage (Vh) show distinct properties in the two cells types. In both, an evident DAP followed the AP at near‐threshold Vh levels, and was accompanied by an enhancement of excitability and spike‐timing precision. This DAP was sensitive to voltage‐gated Na+‐channel block with TTx, but not to partial removal of extracellular Ca2+. Application of 5‐μM anandamide, which inhibited the resurgent and persistent Na+‐current components in a relatively selective way, significantly reduced the amplitude of this particular DAP while exerting poor effects on the foregoing AP. In the presence of background hyperpolarization, DAPs showed an opposite behavior in the two cell types, as in stellate cells they became even more prominent, whereas in pyramidal‐like cells their amplitude was markedly reduced. The DAP observed in stellate cells under this condition was strongly inhibited by partial extracellular‐Ca2+ removal, and was sensitive to the low‐voltage‐activated Ca2+‐channel blocker, NNC55‐0396. This Ca2+ dependence was not observed in the residual DAP evoked in pyramidal‐like cells from likewise negative Vh levels. These results demonstrate that two distinct mechanism of DAP generation operate in mEC layer‐II neurons, one Na+‐dependent and active at near‐threshold Vh levels in both stellate and‐pyramidal‐like cells, the other Ca2+‐dependent and only expressed by stellate cells in the presence of background membrane hyperpolarization. © 2015 Wiley Periodicals, Inc. 相似文献
87.
Matthew Bancone BS Alessandra Sacco PhD Kirkwood E. Personius PT PhD 《Muscle & nerve》2016,54(4):763-768
Introduction: Duchenne muscular dystrophy (DMD) is caused by loss of the structural protein, dystrophin, resulting in muscle fragility. Muscle stem cell (MuSC) transplantation is a potential therapy for DMD. It is unknown whether donor‐derived muscle fibers are structurally innervated. Methods: Green fluorescent protein (GFP)–expressing MuSCs were transplanted into the tibials anterior of adult dystrophic mdx/mTR mice. Three weeks later the neuromuscular junction was labeled by immunohistochemistry. Results: The percent overlap between pre‐ and postsynaptic immunolabeling was greater in donor‐derived GFP+ myofibers, and fewer GFP+ myofibers were identified as denervated compared with control GFP– fibers (P = 0.001 and 0.03). GFP+ fibers also demonstrated acetylcholine receptor fragmentation and expanded endplate area, indicators of muscle reinnervation (P = 0.008 and 0.033). Conclusion: It is unclear whether GFP+ fibers are a result of de novo synthesis or fusion with damaged endogenous fibers. Either way, donor‐derived fibers demonstrate clear histological innervation. Muscle Nerve 54 : 763–768, 2016 相似文献
88.
Ines Testoni Michael Wieser Alessandra Armenti Lucia Ronconi Maria Silvia Guglielmin Paolo Cottone Adriano Zamperini 《Zeitschrift für Psychodrama und Soziometrie》2016,15(1):11-23
The study discusses the construct of spontaneity and its causal relationship with psychological well-being. It develops a preview phase of validation of the SAI-R and its correlation with the Clinical Outcomes for Routine Evaluation-Outcome Measure (CORE-OM) and the Beck Depression Inventory (BDI-II) and assumes the hypothesis that a high level of spontaneity is correlated negatively with low level of well-being and positively with depression. The research involved Italian and Austrian participants, consisting of 166 Italian and 146 Austrian university students. The findings suggested a causal relationship between low spontaneity and psychological suffering. The results obtained confirm the hypothesized model, showing significant negative causal relationship. The verification of this theoretical model on non-clinical samples allows us to set the ground for future use in clinical samples. Furthermore, this result encourages the development of further research into the use of SAI-R. 相似文献
89.
Pérez-Guisado J Scilletta A Cabrera-Sánchez E Rioja LF Perrotta R 《Journal of cutaneous and aesthetic surgery》2012,5(1):38-39
Epidermoid cysts represent the most common cutaneous cysts. They are usually small and benign; however, sometimes they can grow to giant epidermoid cists, and occasionally malignancies develop. Giant epidermoid cysts at the earlobe have never been described but in other locations. We describe a case of a giant epidermoid cyst at the earlobe, a location where such a large cyst has never been reported before. The mass was completely resected and the wound of the pedunculated base was sutured with four stitches of nylon 5/0. Histopathology confirmed the presumptive diagnosis of an epidermoid cyst. Six months after the resection, the patient did not have any relapse of the epidermoid cyst. The earlobe is a potential location for giant epidermoid cysts. Although the clinical diagnosis could be enough, due to the possibility of malignancy and to ensure appropriate diagnosis, we consider that all cysts should be sent to the anatomic pathology laboratory for histological evaluation. 相似文献
90.
Predictors of renal and patient outcomes in atheroembolic renal disease: a prospective study 总被引:3,自引:0,他引:3
Scolari F Ravani P Pola A Guerini S Zubani R Movilli E Savoldi S Malberti F Maiorca R 《Journal of the American Society of Nephrology : JASN》2003,14(6):1584-1590
Atheroembolic renal disease (AERD) is part of a multisystemic disease accompanied by high cardiovascular comorbidity and mortality. Interrelationships between traditional risk factors for atherosclerosis, vascular comorbidities, precipitating factors, and markers of clinical severity of the disease in determining outcome remain poorly understood. Patients with AERD presenting to a single center between 1996 and 2002 were followed-up with prospective collection of clinical and biochemical data. The major outcomes included end-stage renal disease (ESRD) and death. Ninety-five patients were identified (81 male). AERD was iatrogenic in 87%. Mean age was 71.4 yr. Twenty-three patients (24%) developed ESRD; 36 patients (37.9%) died. Cox regression analysis showed that significant independent predictors of ESRD were long-standing hypertension (hazard ratio [HR] = 1.1; P < 0.001) and preexisting chronic renal impairment (HR = 2.12; P = 0.02); use of statins was independently associated with decreased risk of ESRD (HR = 0.02; P = 0.003). Age (HR = 1.09; P = 0.009), diabetes (HR = 2.55; P = 0.034), and ESRD (HR = 2.21; P = 0.029) were independent risk factors for patient mortality; male gender was independently associated with decreased risk of death (HR = 0.27; P = 0.007). Cardiovascular comorbidities, precipitating factors, and clinical severity of AERD had no prognostic impact on renal and patient survival. It is concluded that AERD has a strong clinical impact on patient and renal survival. The study clearly shows the importance of preexisting chronic renal impairment in determining both renal and patient outcome, this latter being mediated by the development of ESRD. The protective effect of statins on the development of ESRD should be evaluated in a prospective study. 相似文献