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   586篇
  免费   25篇
  国内免费   1篇
耳鼻咽喉   16篇
儿科学   46篇
妇产科学   16篇
基础医学   50篇
口腔科学   40篇
临床医学   30篇
内科学   82篇
皮肤病学   23篇
神经病学   26篇
特种医学   56篇
外科学   74篇
综合类   10篇
预防医学   11篇
眼科学   94篇
药学   18篇
肿瘤学   20篇
  2024年   2篇
  2023年   2篇
  2022年   9篇
  2021年   13篇
  2020年   12篇
  2019年   6篇
  2018年   20篇
  2017年   10篇
  2016年   17篇
  2015年   19篇
  2014年   21篇
  2013年   25篇
  2012年   35篇
  2011年   31篇
  2010年   20篇
  2009年   28篇
  2008年   45篇
  2007年   54篇
  2006年   40篇
  2005年   46篇
  2004年   29篇
  2003年   22篇
  2002年   20篇
  2001年   13篇
  2000年   14篇
  1999年   7篇
  1998年   5篇
  1997年   7篇
  1996年   7篇
  1995年   5篇
  1994年   5篇
  1993年   3篇
  1992年   8篇
  1991年   7篇
  1990年   3篇
  1989年   1篇
  1988年   1篇
排序方式: 共有612条查询结果,搜索用时 0 毫秒
1.
The jawbones can be sites of various neoplastic conditions. Given the variety of processes affecting this particular anatomical area, formulation of a precise diagnosis can be challenging to clinicians. Limited jaw movement, pain, and facial asymmetry are common signs among patients, especially those with temporomandibular disorder (TMD). This paper reports a case of primary fibrosarcoma affecting the mandible and surrounding structures in a 14-year-old girl presenting signs and symptoms similar to TMD. Her condition was misdiagnosed, and she was treated for TMD over an extended period before the correct diagnosis was made for fibrosarcoma. The patient underwent surgical resection with postsurgical radiotherapy and chemotherapy and now is being followed up. Although malignant lesions are rare in the temporomandibular joint (TMJ) region, dentists are advised to be aware of the condition and to keep in mind that patients who are admitting for TMD can also possibly be affected from neoplasms. Hence, those patients have to be examined meticulously to avoid misdiagnosis and mistreatment.  相似文献   
2.
Postoperative muscle imbalance was prospectively evaluated in 44 patients who underwent conventional scleral buckling operations. Strabismus was present in 27 of 44 patients (61%). Heterotropia resolved spontaneously during the first six postoperative months in nine of 27 patients (33%). Diplopia persisted in six patients (13.6%) and limitation of ductions occurred in 22 of 44 patients (50%). The risk of developing postoperative strabismus was 2.5 times longer if an implant was placed under a rectus muscle. Otherwise, presence, degree, and direction of the duction deficits did not correlate with placement of a local implant under the corresponding rectus muscles or their antagonists. Reoperation, preoperative detachment of macula and size of the local implant were not statistically correlated with extraocular muscle imbalance. We believe that decrease in postoperative swelling and increase in visual acuity that allows phoria adaptation are the main causes of spontaneous resolution.  相似文献   
3.
Abstract Background: Hypoxic-ischemic encephalopathy (HIE) is still a very important cause of neonatal mortality and morbidity. Recently platelet-activating factor (PAF) has been accused of being responsible for the neuronal damage in hypoxic-ischemic brain.
Methods: Therefore, we conducted a study in newborns with perinatal asphyxia to try to show the relationship between the clinical severity and plasma PAF levels.
Results: Mean plasma levels of 19 asphyxiated infants (997.8 ± 363.5 pg/mL) were significantly higher than that of 20 healthy infants (410.2 ± 148.6 pg/mL, P< 0.0001). Patients with clinically severe HIE had significantly higher levels of PAF (1494.2 ± 386.6 pg/mL) when compared with patients with mild HIE (815 ± 114.5 pg/mL) and with moderate HIE (828.3 ± 61.1 pg/mL). There was a significant correlation between plasma PAF concentration and arterial pH and base deficit, but no correlation with platelet and leukocyte counts.
Conclusions: Plasma PAF levels correlating with the severity of HIE is interpreted to mean that high PAF levels may be an indicator of clinical severity and probably the poorer prognosis of patients with HIE.  相似文献   
4.
Testicular tumours have many different manifestations, including hydrocele formation. Herein, we present an extremely rare case of testicular mesothelioma presenting with left hydrocele, but without risk factors. Left radical inguinal orchidectomy was performed, and pathological examination revealed a malignant mesothelioma of the tunica vaginalis of the testis. No infiltration of the spermatic cord was evident, and upon advanced radiological evaluation, no sign of metastasis was detected. Follow-up was still ongoing in our urology outpatient clinic at the time of this report. Although hydrocele is a simple and common condition that is easy to diagnose, a detailed investigation should be performed. Thus, when encountering a patient with hydrocele, the clinician should evaluate the possibility of the presence of an underlying testicular/paratesticular tumour, including a rare one such as mesothelioma of the tunica vaginalis.  相似文献   
5.
Introduction The aim of the study was to demonstrate the possible effects of preoperative intra-articular, intravenous, or intrathecal administration of morphine on postoperative pain management.Materials and methods Sixty patients undergoing arthroscopic menisectomy were included. Spinal anesthesia was performed in the lateral decubitus position with 3 ml of 0.5% hyperbaric bupivacaine, and the patients were randomized into 4 groups. The IVM (intravenous, iv, morphine) group received 3 mg of iv morphine after completion of spinal anesthesia, the ITM (intrathecal morphine) group received 0.3 mg of morphine together with bupivacaine during spinal anesthesia, the IAM (intra-articular morphine) group received 3 mg intra-articular morphine diluted in 10 ml of saline after spinal anesthesia had been induced but 15 min before surgery, while the C (control) group did not receive any drugs in addition to spinal anesthesia. The sensory block level was determined 15 min after spinal anesthesia. Pain at rest (by visual analogue scale, VAS) and pain at 30° of flexion (by verbal rating scale, VRS) were evaluated during each of the first 2 h of the postoperative period and once every 4 h thereafter until 24 h. In each group; the number of patients in need of analgesics, the timing of the first analgesic intake (duration of analgesia), and the cumulative dose of analgesics were recorded.Results The mean duration of analgesia in the IAM group was significantly longer and the mean analgesic intake was significantly lower when compared with the other groups (p<0.05). The mean VAS value of the ITM group at the 4th postoperative hour was significantly lower than that of the other groups. Mean VAS values at 8 and 12 h and mean VRS values at 4 and 8 h were significantly lower in the ITM and IAM groups (p<0.05). The ITM group had the highest rates of nausea, vomiting, pruritus, and headache (p<0.05).Conclusion It was concluded that the preoperative administration of morphine, either intrathecally or intra-articularly, provides postoperative pain relief. Of these two, the intra-articular route seems to be superior in terms of fewer side-effects (nausea, vomiting, and pruritus), longer duration of analgesia, and reduction of total need for analgesics.  相似文献   
6.
It has been suggested that urinary glycosaminoglycans (GAGs) form a natural defense mechanism against urinary tract infections (UTIs). This study investigated whether urinary GAGs play a role in pediatric UTIs, and whether urinary GAG level can be used to differentiate upper UTI from lower UTI. Forty-one children with UTIs (33 girls and eight boys; mean age 5.4+/-3.7 years) and 46 age- and sex-matched healthy children (35 girls and 11 boys; mean age 6.6+/-3.9 years) were included in the study. Urinary GAG levels were measured at the onset of acute infection and after a 10-day course of antibiotic treatment. Group GAG findings were compared, and comparisons were also made with the patients divided according to sex and according to UTI type (upper versus lower). The mean urinary GAG level in the patient group at the onset of acute infection (pretreatment) was significantly higher than the mean level in the control group (132.2+/-104.8 mg/g vs 42.2+/-27.1 mg/g creatinine, respectively; P <0.01). In the patient group, the mean urinary GAG level after antimicrobial therapy was significantly lower than the pretreatment level (75.9+/-52.1 mg/g vs 132.2+/-104.8 mg/g creatinine, respectively; P <0.01). However, the mean post-treatment level was still higher than the mean level in the controls ( P <0.05). There was no significant difference in urinary GAG levels when patients were categorized as upper versus lower UTI ( P >0.05). The study results suggest that GAGs play an important role in the pathogenesis of UTIs in children, and that measurement of urinary GAGs may be a valuable noninvasive method for evaluating UTIs in this patient group. However, this assay cannot be used to differentiate upper UTI from lower UTI in children.  相似文献   
7.
PURPOSE: To determine the interaction of heavy silicone oil with various intraocular lens (IOL) materials and whether heavy silicone oil covers the silicone IOL optic as silicone oil does. SETTING: Department of Ophthalmology, Dokuz Eylul University, Izmir, Turkey. METHODS: The study group comprised 5 poly(methyl methacrylate) (PMMA) IOLs, 4 foldable silicone IOLs, 5 foldable hydrophilic acrylic IOLs, and 5 foldable hydrophobic acrylic IOLs. Each IOL was bathed in balanced salt solution (BSS) for 10 minutes and then placed in heavy silicone oil dyed with Sudan Black for another 10 minutes. Afterward, each IOL was reimmersed in BSS for 5 minutes and examined under the light microscope. Digital images were analyzed to determine the optic area covered with heavy silicone oil. RESULTS: The mean heavy silicone oil coverage was 7.05% +/- 7.88% (SD) (range 1.13% to 20.54%) on PMMA IOLs, 100% on silicone IOLs, 12.17% +/- 11.43% (range 1.25% to 31.52%) on hydrophobic acrylic IOLs, and 34.64% +/- 13.28% (range 12.57% to 44.42%) on hydrophilic acrylic IOLs. Heavy silicone oil coverage of silicone IOLs was statistically significantly greater than the coverage of other IOL materials. CONCLUSION: Heavy silicone oil acted the same as silicone oil and covered the entire surface of silicone IOLs.  相似文献   
8.
9.

PURPOSE

The objective of this study was to compare the light transmittance of zirconia in different thicknesses using various light curing units.

MATERIALS AND METHODS

A total of 21 disc-shaped zirconia specimens (5 mm in diameter) in different thicknesses (0.3, 0.5 and 0.8 mm) were prepared. The light transmittance of the specimens under three different light-curing units (quartz tungsten halogen, light-emitting diodes and plasma arc) was compared by using a hand-held radiometer. Statistical significance was determined using two-way ANOVA (α=.05).

RESULTS

ANOVA revealed that thickness of zirconia and light curing unit had significant effects on light transmittance (P<.001).

CONCLUSION

Greater thickness of zirconia results in lower light transmittance. Light-emitting diodes light-curing units might be considered as effective as Plasma arc light-curing units or more effective than Quartz-tungsten-halogen light-curing units for polymerization of the resin-based materials.  相似文献   
10.
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