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   185篇
  免费   10篇
耳鼻咽喉   2篇
儿科学   10篇
基础医学   15篇
口腔科学   30篇
临床医学   6篇
内科学   15篇
皮肤病学   2篇
神经病学   42篇
特种医学   8篇
外科学   52篇
综合类   2篇
预防医学   2篇
眼科学   1篇
药学   7篇
肿瘤学   1篇
  2024年   1篇
  2023年   1篇
  2021年   1篇
  2020年   2篇
  2019年   5篇
  2018年   2篇
  2017年   4篇
  2016年   3篇
  2015年   10篇
  2014年   16篇
  2013年   8篇
  2012年   21篇
  2011年   20篇
  2010年   8篇
  2009年   6篇
  2008年   7篇
  2007年   18篇
  2006年   14篇
  2005年   11篇
  2004年   7篇
  2003年   5篇
  2002年   8篇
  2000年   2篇
  1999年   3篇
  1998年   3篇
  1996年   1篇
  1995年   2篇
  1993年   1篇
  1992年   2篇
  1990年   1篇
  1988年   1篇
  1986年   1篇
排序方式: 共有195条查询结果,搜索用时 31 毫秒
41.
Lumboperitoneal shunting is widely used for the surgical management of pseudotumor cerebri and other pathologies such as communicating hydrocephalus. Although it is a safe method, it could be associated with complications including subarachnoid hemorrhage, subdural and rarely intracerebral hematoma. A 44-year-old female applied to our clinic with complaints of severe headache, retroorbital pain and blurred vision. Lumbar puncture demonstrated cerebrospinal fluid opening pressure of cmH2O. A non-programmable lumboperitoneal shunt with two distal slit valves was inserted due to pseudotumor cerebri. She deteriorated shortly after surgery. Immediate cranial computed tomography scan revealed a right parietal intracerebral hematoma. Development of intracerebral hematoma following lumboperitoneal shunt is a rare complication. We discuss this rare event accompanied by the literature.  相似文献   
42.
Primary meningeal osteosarcomas are rare tumors, with only 19 reported cases in the literature; only 4 of these, including the present case, are in pediatric patients. In this report, the authors present the case of an 8-year-old boy with a history of generalized tonic-clonic seizures who was found to harbor a meningeal osteosarcoma within the sylvian fissure. Initial working diagnoses included meningioma and glioma. After tumor enlargement and progressive symptoms, the patient underwent a large frontotemporal craniotomy and complete resection of the lesion, which recurred 6 and 12 months after the initial surgery and was surgically treated after each recurrence. The rarity of primary meningeal osteosarcomas can make their diagnosis difficult, and histopathological evaluation is mandatory for diagnosis. Because of their fast progression, they must be treated aggressively by means of surgery, chemotherapy, and radiotherapy.  相似文献   
43.
We present the long-term clinical and angiographic follow-up results of 100 consecutive intracranial aneurysms treated with Onyx liquid embolic system (MTI, Irvine, Calif.), either alone or combined with an adjunctive stent, in a single center. A total of 100 aneurysms in 94 patients were treated with endosaccular Onyx packing. Intracranial stenting was used adjunctively in 25 aneurysms including 19 during initial treatment and 6 during retreatment. All aneurysms except two were located in the internal carotid artery. Of the 100 aneurysms, 35 were giant or large/wide-necked, and 65 were small. Follow-up angiography was performed in all 91 surviving patients (96 aneurysms) at 3 and/or 6 months. Follow-up angiography was performed at 1, 2, 3, 4 and 5 years in 90, 41, 26, 6 and 2 patients, respectively. Overall, aneurysm recanalization was observed in 12 of 96 aneurysms with follow-up angiography (12.5%). All 12 were large or giant aneurysms, resulting in a 36% recanalization rate in the large and giant aneurysm group. One aneurysm out of 25 treated with the combination of a stent and Onyx showed recanalization. There was also no recanalization in the follow-up of small internal carotid artery aneurysms treated with balloon assistance only. At final follow-up, procedure- or device-related permanent neurological morbidity was present in eight patients (8.3%). There were two procedure-related and one disease-related (subarachnoid hemorrhage) deaths (mortality 3.2%). Delayed spontaneous asymptomatic occlusion of the parent vessel occurred in two patients, detected on routine follow-up. Onyx provides durable aneurysm occlusion with parent artery reconstruction resulting in perfectly stable 1-year to 5-year follow-up angiography both in small aneurysms treated with balloon assistance only (0% recanalization rate) and large or giant aneurysms treated with stent and Onyx combination (4% recanalization rate). Endosaccular Onyx packing with balloon assistance may not be adequate for stable long-term results in those with a large or giant aneurysm. However, the recanalization rate of 36% in these aneurysms is better than the reported results with other techniques, i.e., coils with or without adjunctive bare stents.  相似文献   
44.
Many types of local flaps are commonly used for the repair of circular skin defects. In this paper, we described that the “North Star” design is useful for aesthetic removal of benign skin lesions.  相似文献   
45.
Atypical midline cleft with duplication of the metopic suture.   总被引:1,自引:0,他引:1  
INTRODUCTION: In contrast to the common clefts of the lip, alveolus and palate, the atypical clefts of the face may come in myriad patterns of clinical expression and are often not easy to define. PURPOSE: In this report, a case of median craniofacial dysraphia is described. PATIENT: At presentation, the 3-month-old male patient had a bilateral complete cleft of the lip, alveolus and palate. The nose was wide and a horn was present on the nasal dorsum. 3-D CT AND MRI REVEALED: Duplication of the metopic suture ending at the wide anterior fontanel; orbital hypertelorism; midline cranial cleft ending just superior to the nasal dorsum; frontoethmoidal encephalocoele and holoprosencephaly. The presence of two metopic sutures was confirmed during surgery. CONCLUSION: The presented case carries the characteristics of the median cleft face syndrome. However, it differs from similar cases in two respects. First, the patient had two metopic sutures, one on either side of the cranial extension of the median cleft. Second, the patient had a bilateral cleft lip in contrast to the expected median cleft lip deformity.  相似文献   
46.

Purpose

Knowledge of the nasopalatine canal (NPC) is necessary for understanding the morphology and pathogenesis of lesions that occur in this region. The purpose of the present study was to analyze the dimensions and anatomic characteristics of the NPC in a pediatric population using cone-beam computed tomography (CBCT).

Study design

Reformatted sagittal, coronal, and axial slices of 368 individual CBCT images were analyzed with regard to dimensions and anatomic features of the NPC.

Results

Funnel shape of the NPC was most commonly found [26.9 % (99)], followed by banana shape [19.6 % (72)]. There was no statistically significant difference (p = 0.317) between girls and boys in terms of NPC shape. The mean width of incisive foramen was found to be 2.53 mm with a significant difference (0.002). The mean NPC length was found to be 10.83 mm and the mean canal length was found to be significantly longer in boys than girls (p < 0.000).

Conclusion

The present study provides new information on the literature concerning the identification of the anatomical structure of NPC. This finding may assist clinicians in understanding the morphology and preventing possible complications in this region.  相似文献   
47.
The toxicity of aminoglycosides including gentamicin (GEN), the most widely used drug in this category, is believed to be related to the generation of reactive oxygen species (ROS) in the kidney. Aminoguanidine (AG) is known as an effective antioxidant and its free radical scavenger effects may protect GEN-induced acute renal failure (ARF). Therefore, this study was focused on investigating the possible protective effect of AG against GEN-induced nephrotoxicity in an in vivo rat model. We investigated the effects of AG on GEN-induced changes in renal tissue malondialdehyde (MDA) levels; nitric oxide (NO) generation; glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities; glutathione (GSH) content; serum creatinine (Cr) and blood urea nitrogen (BUN) levels. Morphological changes in the kidney were also examined using light microscopy. GEN administration to control group rats increased renal MDA and NO levels but decreased GSH-Px, SOD, CAT activities and GSH content. AG administration with GEN injection resulted in significantly decreased MDA, NO generation and increased GSH-Px, SOD, CAT activities and GSH content when compared with GEN alone. Serum levels of Cr and BUN significantly increased as a result of nephrotoxicity. Also, AG significantly decreased Cr and BUN levels. Morphological changes in the kidney, including tubular necrosis, intracellular edema, glomerular and basement membrane alterations were evaluated qualitatively. Both biochemical findings and histopathological evidence showed that administration of AG reduced the GEN-induced kidney damage. We propose that AG acts in the kidney as a potent scavenger of free radicals to prevent the toxic effects of GEN both at the biochemical and histological level.  相似文献   
48.
Erdogan H  Fadillioglu E  Emre MH 《Toxicology》2006,228(2-3):219-228
The aim of this study was to investigate whether the protective effect of endothelin-A (ET(A)) receptor antagonist BQ-123 against renal ischemia reperfusion (I/R) injury is related to nitric oxide (NO) production. Sprague-Dawley rats were divided into six groups: control, I/R, N sup omega nitro-L-arginine methyl ester (L-NAME), BQ, BQ+L-NAME, BQ+L-NAME+L-Arg groups. After urethane anesthesia, 30min renal ischemia and 2h reperfusion were performed in all groups except control group. Mean arterial pressures (MAP) during reperfusion in all L-NAME-treated groups were higher than during pre-ischemia and ischemia, however, MAP at 60th and 120th minute of reperfusion in control and BQ groups were lower than during ischemia. MAP of L-NAME-treated groups were significantly higher than the other groups during reperfusion period. The I/R caused lipid peroxidation and protein oxidation, however, BQ-123 treatment prevented oxidant injury. The inhibition of NO production prevented effect of BQ-123 treatment. Also, BQ-123 treatment caused an increase in superoxide dismutase and catalase activities. Both BQ-123 and L-NAME treatments prevented high xanthine oxidase activity. BQ-123 prevented risen myeloperoxidase activity and L-NAME reversed this effect of BQ-123 just like the addition of L-arginine to the treatment altered the effect of L-NAME. The plasma BUN was affected as increasing manner from L-NAME treatments; on the other hand, plasma Cr and Na concentrations were affected as decreasing manner from BQ-123 treatments. ET(A) receptor antagonist BQ-123 may be revealed a protective agent against renal I/R injury with a possible secondary pathway via its antioxidant effects. We suggest that BQ-123 may mediate the protective effect via a NO-dependent mechanism.  相似文献   
49.
50.
A lambda gt11 yeast genomic library was screened with antibodies directed against yeast RNA polymerases A, B, and C. Thirty-five individual recombinant phages that expressed proteins in Escherichia coli that were antigenically related to RNA polymerases A, B, or C were isolated by using 22 distinct antisera. Thus, all 22 genes for the RNA polymerase subunits were potentially cloned. In three cases (lambda A-43, lambda A-40, and lambda A-34.5), an antigenic protein was expressed in E. coli with the same molecular weight as the corresponding subunit. When lambda A-40 DNA was used to hybrid-select yeast mRNA, the protein translated in vitro was the expected size for the A-40 subunit, further supporting our isolation of the A-40 gene. However, mRNA hybrid selected by lambda A-27 DNA did not code for a protein of the correct size. The lengths of the mRNA that hybridized to phage lambda A-190 or lambda C-160 DNA on RNA blots were in agreement with the predicted sizes of the coding regions of the corresponding genes. As predicted by our previous immunological results, yeast DNA inserts of the lambda A-190 and lambda C-160 clones cross-hybridized to the B-220 subunit gene. The cloned genes for the RNA polymerase subunits will prove to be valuable tools for the study of the function, regulation, and genetics of the yeast RNA polymerases.  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