全文获取类型
收费全文 | 692篇 |
免费 | 36篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 22篇 |
儿科学 | 45篇 |
妇产科学 | 10篇 |
基础医学 | 44篇 |
口腔科学 | 17篇 |
临床医学 | 73篇 |
内科学 | 166篇 |
皮肤病学 | 7篇 |
神经病学 | 47篇 |
特种医学 | 56篇 |
外科学 | 99篇 |
综合类 | 10篇 |
预防医学 | 36篇 |
眼科学 | 43篇 |
药学 | 23篇 |
肿瘤学 | 32篇 |
出版年
2021年 | 9篇 |
2020年 | 10篇 |
2019年 | 10篇 |
2018年 | 12篇 |
2017年 | 14篇 |
2016年 | 16篇 |
2015年 | 16篇 |
2014年 | 17篇 |
2013年 | 28篇 |
2012年 | 39篇 |
2011年 | 40篇 |
2010年 | 23篇 |
2009年 | 25篇 |
2008年 | 42篇 |
2007年 | 37篇 |
2006年 | 49篇 |
2005年 | 39篇 |
2004年 | 27篇 |
2003年 | 21篇 |
2002年 | 19篇 |
2001年 | 8篇 |
2000年 | 8篇 |
1999年 | 18篇 |
1998年 | 11篇 |
1997年 | 10篇 |
1996年 | 13篇 |
1995年 | 8篇 |
1994年 | 16篇 |
1993年 | 10篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 6篇 |
1988年 | 12篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 13篇 |
1984年 | 5篇 |
1983年 | 9篇 |
1982年 | 7篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1976年 | 6篇 |
1972年 | 2篇 |
1971年 | 5篇 |
1969年 | 2篇 |
1965年 | 3篇 |
1963年 | 4篇 |
1962年 | 2篇 |
1956年 | 2篇 |
排序方式: 共有730条查询结果,搜索用时 20 毫秒
51.
OBJECTIVES: The aim of this study was to investigate the effects of environmental light-dark changes on the outcome of mild traumatic brain injury (MTBI) using an experimental rodent model. The functions of endogenous and exogenous melatonin on the outcome of injury were also investigated METHODS: Mild traumatic brain injury was experimentally induced in 56 male Sprague-Dawley rats using a weight-drop device. Animals were divided into four groups of 14 each as follows: (i) sham-operated (trauma only, normal day-night cycle), (ii) treated with melatonin (trauma+melatonin, normal day-night cycle), (iii) darkness-induced (trauma+48 h constant dark), and (iv) treated with melatonin and darkness-induced (trauma+48 h constant dark+melatonin). Melatonin (50 mg/kg) was administered, intraperitoneally, immediately after trauma. EEG recordings were taken at three time periods (pretrauma, immediately after trauma, and 48 h after trauma). Motor functions were tested pretrauma, 24 and 48 h post-trauma. Serum melatonin levels were determined pretrauma and 48 h post-trauma. Tissue samples from right frontal area were taken 48 h after trauma for light and electron microscopic examinations. CONCLUSION: Following MTBI light deprivation alone and light deprivation in combination with exogenously administered melatonin indicated significant neuroprotective effects. Although there may be other important pathways, darkness-induced elevation in endogenous melatonin secretion appears to play an important role in this neuroprotective outcome. 相似文献
52.
OBJECTIVE: The fluoroscopic image from the second plan (oblique) tube of an upper ureteral stone close to the crista iliaca may be superimposed on the pelvic bones during SWL using the Siemens Lithostar with the patient in the prone position. This creates difficulty in imaging and targeting of the stone and can necessitate using ureteral catheters before treatment and/or intravenous contrast injection during SWL. We describe a very simple, yet effective method for easier visualization of the stone under this circumstance. METHODS: Between March 1992 and February 2003, we treated 1561 patients with ureteral stones by SWL with the Siemens Lithostar. The stones were localized in the upper ureter in 841. The image of the stone from the second plan (oblique) tube was superimposed on the pelvic bones in 221 in whom visualization of the stone was hardly possible with the standard prone position. By simply rotating the patient 180 degrees on the table, the superimposition of the image of the stone on the pelvic bone was obviated. This resulted in easier and better imaging of the stone during SWL. It also allowed for a clear and superior image to the treating physician during SWL. The energy and shock waves, utilization of anesthesia, number of treatment sessions, auxiliary measures, and complications were noted. Stone load was recorded in square centimeters (cm(2)). Patients were evaluated by intravenous urogram or KUB and ultrasonography when stone-free or CIRF (nonobstructive and noninfectious insignificant fragments < or =4mm) status was noted at the fluoroscopic control 2 to 4 weeks after the last session. Final CIRF decision was made 10-12 weeks after the last session. SWL was regarded as failure if no fragmentation was noted after the 3rd session. Therapy was continued if fragmentation was noted. RESULTS: The median age was 40 (range 5-85). The mean stone burden was 0.8 (range 0.24-2.9) cm(2). No indwelling ureteral stents were placed in any patients before and during treatment. The mean number of shock waves and energy used for the entire patient population was 2007 and 17.5kV, respectively. The median and average treatment session was 1 and 1.7, respectively. A total of 196 patients (89%) were rendered stone-free. Clinically insignificant residual fragments were present in 18 (8%). SWL was unsuccessful in 7 (3%) patients. These stones were removed by ureterorenoscopy. Intravenous contrast administration was not used to facilitate stone targeting during SWL. Anesthesia, in the form of analgesic sedation, was used in 7 (3%) patients. We did not observe any complications and adverse effects. CONCLUSIONS: The technique described hereby does not have an affect on coupling; it only provides a superior image of the stone to the treating physician. We advocate its application in all patients with upper ureteral stones close to the crista iliaca when the fluoroscopic image of the stone from the second plan (oblique) tube is superimposed on pelvic bones during SWL in prone position. 相似文献
53.
54.
Onal C Yakinci C Kocak A Erguvan R Tekiner A Kutlu R Ozcan C Gul A 《Pediatric neurosurgery》2002,36(2):90-95
Spinal cord injury with or without trauma has been reported in the perinatal period. The prognosis depends primarily on diagnosis of the level, extent and nature of the lesion, established by correlations between clinical, imaging and electrophysiological data. A 25-day-old boy with normal birth weight delivered at term by cesarean section was transferred to In?nü University Turgut Ozal Medical Center because of respiratory distress and brachial diplegia. A suspicious medullary lesion on cervical computerized tomography was confirmed as an intramedullary lesion extending from C3 to D1 on magnetic resonance imaging (MRI). Emergent surgery consisting of exposure of the lesion site and interlaminar direct puncture of the lesion under fluoroscopy revealed that the pathology was an intramedullary hematoma. The partial evacuation of the lesion with direct puncture, the patient's neurological improvement and close follow-up of the patient with ultrasonography, electrophysiology and MRI are discussed in the light of recent literature. 相似文献
55.
Encapsulation of insulin in chitosan-coated alginate beads: oral therapeutic peptide delivery 总被引:3,自引:0,他引:3
Onal S Zihnioğlu F 《Artificial cells, blood substitutes, and immobilization biotechnology》2002,30(3):229-237
Insulin was encapsulated in calcium alginate beads coated with chitosan. Its release from alginate-chitosan and alginate-chitosan-glutaraldehyde beads was studied in artificial gastric (pH 1.2) and intestinal (pH 7.5) fluids. By comparing the release amounts, the ionic interaction between alginate-chitosan matrix with the medium pH's, intestinal fluid was found to be the better. The degradation of released insulin was also searched, even after 6 h incubation, the beads remained stable and the undegraded insulin seemed to be sufficient for the physiological conditions. Consequently, it can be said that the system can be offered for oral delivery of the therapeutic peptide drug insulin. 相似文献
56.
Kural AR Demirkesen O Onal B Obek C Tunc B Onder AU Yalcin V Solok V 《Urologia internationalis》2003,71(2):190-196
INTRODUCTION: The increase in the detection of renal tumors incidentally in earlier stages has enhanced the enthusiasm for nephron-sparing surgery (NSS). PATIENTS AND METHODS: We performed NSS in 76 patients (53 male, 23 female) with a mean age 52.3 between December 1988 and September 2001. Patients were sub-classified into 2 groups as elective or imperative indication group. They were compared regarding surgical technique, time of surgery, pathological analysis, complications, and disease free status. RESULTS: Elective indication group (group I) with a normal contralateral kidney consisted of 50 patients, whereas there were 26 patients in the imperative indication group (group II). Tumors were incidentally detected in 63%; 74% in group I and 42% in group II. Although the mean diameter of the tumor was slightly higher in group II (39.1 vs. 36.3 mm), this difference did not reach statistical significance (p > 0.05). The partial nephrectomy was performed more frequently compared to enucleation in group I (90 vs. 69%, p = 0.050). However, the mean operation time as well as the mean clamping time did not differ significantly between the two groups (p > 0.05). In the histological evaluation tumors were benign in 16 (21%) and malignant in 60 patients. All of the patients but one with renal cell carcinoma had stage T1-T2 disease. Major complications were observed in 14 (18%) and 12 were from group II. Complication rate was significantly higher in group II (p = 0.000). Of 60 patients with renal cell carcinoma, 2 died of unrelated causes. One patient died with multiple visceral metastases. One patient was lost to follow-up. In the remaining 56 patients with a mean follow-up of 37.1 months (1-152), local recurrence or distant metastases were not detected. Serum creatinine levels have remained almost the same compared to preoperative levels (1.2 +/- 0.6 vs. 1.5 +/- 0.9). Overall and cancer-specific survivals were 100 and 100% in group I, 85 and 95% in group II, and 94 and 98% for the entire patient population, respectively. CONCLUSION: NSS is an effective and reliable treatment in low stage renal tumors. It prevents unnecessary nephrectomy in benign lesions that could not be diagnosed preoperatively. However, the patients who underwent NSS with elective indication outcome with better results, compared to those with imperative indication. 相似文献
57.
BACKGROUND: Generalized aggressive periodontitis is described as a clinical entity affecting both deciduous and permanent dentition with extensive alveolar bone loss, mobility, and exfoliation of all or many teeth. Controversy exists on dental implant use to restore missing dentition in younger patients. METHODS: This case report presents a patient diagnosed with aggressive periodontitis who has lost all but 4 of her teeth. Her personal and functional desires led us to include implant therapy in her treatment plan. The hematological data are presented with an analysis of the immunological profile. RESULTS: Dental implants were placed, and following 3 months of osseointegration, an implant-supported prosthesis was completed. The patient was followed up for 36 months. CONCLUSIONS: This case report presents an alternative treatment for rehabilitating dentition in a young patient treated for aggressive periodontitis. Similar case studies may help eliminate some of the controversy that exists regarding the use of dental implants in aggressive periodontitis patients. 相似文献
58.
Atmaca M Tezcan E Kuloglu M Onal S 《European archives of psychiatry and clinical neuroscience》2003,253(1):34-36
Post-traumatic stress disorder (PTSD) has been associated with decreased neopterin levels. In the present study, we evaluated
whether this low neopterin levels would normalize following pharmacotherapy with sertraline in PTSD. Fourteen patients with
PTSD and 14 controls were enrolled in the study. A clinical evaluation and measurements of neopterin levels before and after
sertraline treatment were performed. In addition, all patients were assessed with the Clinician Administered PTSD Scale (CAPS).
The mean neopterin levels were significantly lower in the patient group than control group at baseline and were negatively
correlated with the duration of illness, or severity of illness. Sertraline treatment decreased the symptoms of PTSD; however
this was not accompanied by a significant increase in neopterin production. In conclusion, our results reveal that the failure
for neopterin to normalize through symptom alleviation suggests that either neopterin may be a trait marker of the illness,
or that more sustained treatment is necessary to elevate the neopterin production.
Received: 30 September 2002 / Accepted: 12 December 2002
Correspondence to Dr. Murad Atmaca 相似文献
59.
Environmental exposure to asbestos in eastern Turkey 总被引:1,自引:0,他引:1
Hasanoğlu HC Gokirmak M Baysal T Yildirim Z Koksal N Onal Y 《Archives of environmental health》2003,58(3):144-150
In this study, the authors investigated the prevalence of asbestos-related disorders among the inhabitants of Güzelyurt, a town in Malatya, located in eastern Turkey. The authors examined river bed, white soil, and stucco samples taken from various locales in Güzelyurt, and they confirmed the presence of tremolite and chrysotile asbestos fibers. Subjects (N = 920; 449 males and 471 females) were examined by photofluoroscopy. Eighty-five patients (9.2%) had asbestos-related radiological findings; risk increased with age. Calcified pleural plaques were seen more frequently in individuals > or = 50 yr of age, compared with younger subjects (p < 0.01). Asbestos-related disorders were prevalent in the inhabitants of Güzelyurt, the population of which is exposed environmentally to asbestos--primarily the result of the stuccoing and whitewashing of houses with soil that contains asbestos. 相似文献
60.
Dinah Gould BSc MPHIL PHD RGN RNT Cert ED DipN Pam Smith Bnurs MSc PHD RGN DN HV Cert Ed RNT Susan Payne BA RGN RNT ONC & Thomas Aird BA RGN RNT 《Journal of advanced nursing》1999,29(6):1308-1317
The needs of postregistration students pursuing degree-linked clinical courses have received little attention and there are few insights concerning their aspirations when they enrol on such courses. Thus the aim of this study was to explore postregistration students' perceptions of the specific needs of their patient/client group and to examine how they envisaged the course on which they had just enrolled might help them to meet these needs in addition to their own requirements for professional and personal development. Data were collected by group interview from 62 students enrolling on eight different postregistration courses, all employed in an acute hospital trust. The results were analysed inductively. They indicated that students had internalized the state of the healthcare market and were keenly aware of the need to fulfil the expectations of employers and the public, while fulfilling their own needs for education and pursuing their own professional and career trajectories. They appeared ambitious and yet appeared to demonstrate empathy for patients and their families and felt a tremendous desire to provide care of a high quality through the optimal development of technical expertise. Students' emphasis on the importance of keeping abreast of technological developments should not be lightly dismissed considering its prominent position within the acute areas where they were employed, especially as it did not replace their desire to promote the caring aspects of their work. 相似文献