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   3361篇
  免费   101篇
  国内免费   64篇
儿科学   52篇
妇产科学   3篇
基础医学   221篇
口腔科学   5篇
临床医学   358篇
内科学   58篇
神经病学   260篇
特种医学   630篇
外科学   1459篇
综合类   228篇
预防医学   53篇
药学   69篇
  1篇
中国医学   19篇
肿瘤学   110篇
  2024年   2篇
  2023年   38篇
  2022年   74篇
  2021年   102篇
  2020年   104篇
  2019年   99篇
  2018年   131篇
  2017年   117篇
  2016年   99篇
  2015年   117篇
  2014年   220篇
  2013年   188篇
  2012年   130篇
  2011年   192篇
  2010年   137篇
  2009年   170篇
  2008年   147篇
  2007年   175篇
  2006年   126篇
  2005年   152篇
  2004年   122篇
  2003年   86篇
  2002年   78篇
  2001年   69篇
  2000年   78篇
  1999年   65篇
  1998年   56篇
  1997年   62篇
  1996年   34篇
  1995年   36篇
  1994年   33篇
  1993年   41篇
  1992年   31篇
  1991年   31篇
  1990年   22篇
  1989年   19篇
  1988年   18篇
  1987年   22篇
  1986年   16篇
  1985年   13篇
  1984年   8篇
  1983年   4篇
  1982年   12篇
  1981年   8篇
  1980年   6篇
  1979年   11篇
  1978年   10篇
  1977年   10篇
  1974年   2篇
  1970年   2篇
排序方式: 共有3526条查询结果,搜索用时 812 毫秒
81.
82.

Background

In 1999, the Japanese Orthopaedic Association decided to develop a new Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). The final version of the JOACMEQ, comprising 24 questions and five domains (cervical spine function (CF); upper extremity function (UF); lower extremity function (LF); bladder function (BF); and quality of life (QOL)), was established after three nationwide investigations. The fourth investigation, reported in this paper, was performed to confirm the responsiveness of the questionnaire.

Methods

A total of 137 patients with cervical myelopathy were included in the study. Each patient was interviewed twice using the JOACMEQ before and after treatment. At the second interview, the patients self-rated their condition in five domains for “worse,” “somewhat worse,” “no change,” “somewhat better,” or “better,” and these scores were defined as the external assessment rating. The difference of the points in five domains between the first and the second interview was calculated against each external assessment. Based on the results, substantial clinical benefit (SCB) thresholds for the JOACMEQ were determined.

Results

The statistically significant median values of the acquired points were 17.5 for CF, 16.0 and 21.0 for UF, 27.0 and 20.5 for LF, 13.0 for BF, and 29.0 for QOL. After consideration of the results, the committee decided that an acquired point ≥20 could be interpreted as representing an SCB threshold for the JOACMEQ.

Conclusion

We have concluded that a treatment can be judged to be effective for a patient if 1) The patient give all answers for the questions necessary to calculate the functional score of a domain and an increase of ≥20 points is obtained for that score, or 2) The functional score after treatment is > 90 points even if the answer for the unanswered questions was supposed to be the worst possible choice.  相似文献   
83.
Background contextVertebral hemangiomas (VHs) are called benign tumors but are actually just vascular malformations. The diagnosis and treatment for aggressive VHs is still controversial, due to their rarity.PurposeTo evaluate the safety and efficiency of the present diagnostic methods and treatment choices.Study designA retrospective study of aggressive VHs with neurologic deficit.Patients sampleA total of 29 consecutive aggressive VH cases were diagnosed and treated in our department since 2001.Outcome measuresWe routinely took anteroposterior and lateral spinal roentgenograms, computed tomography, and magnetic resonance images.MethodsTrocar biopsy is indicated in suspected malignant cases. Radiotherapy was usually our first choice if the neurologic deficit was mild or developed slowly. Surgery was indicated if the neurologic deficit was severe or developed quickly or if the radiotherapy was not effective.ResultsThis series included 12 males and 17 females, and the mean age at diagnosis was 44.0 years (range, 21–72 years). Ten patients had radiculopathy, 1 had cauda equina syndrome, and 18 cases had myelopathy. Twenty-one cases had lesions in the thoracic spine, 5 in the lumbar, and 3 in the cervical region. Eleven cases had untypical image findings, including five cases with pathologic vertebral fracture. The neurologic compression came from only epidural soft tumor mass in 18 cases, whereas it came from both bony compression and soft lesion in the other 11 cases. Ten cases had radiotherapy alone, but two failed and had surgery later. Twenty-one cases had surgery. In the 12 cases having surgical decompression without vertebroplasty, the average estimated blood loss was 1900 mL, and it was 1093 mL for the eight cases having decompression with vertebroplasty. The average follow-up was 51.1 months (range, 24–133 months). There was no recurrence in those cases with radiotherapy, whereas three had local recurrence in those six cases treated by surgical decompression alone without radiotherapy.ConclusionsIn aggressive VHs, epidural soft-tissue compression was usually the main reason for neurologic deficit. In cases with rapid progressive and/or severe myelopathy, posterior decompression and stabilization could be combined with intraoperative vertebroplasty to reduce blood loss.  相似文献   
84.
探讨酸枣仁及其常见伪品的性状鉴别,确保临床用药的安全、有效。取酸枣仁及其常见伪品,对外观性状进行比对讨论发现酸枣仁及其伪品在外观性状有明显区别。性状鉴别方法能有效地识别酸枣仁及其伪品。  相似文献   
85.
Minimally invasive procedures have been increasing in spine surgery, and interest in robotic systems has inclined. In this study, we aimed to evaluate feasibility of a robotic-assisted thoracic spine interbody fusion in a swine model. Neurosurgeons performed the surgical procedures with robotic surgery certificates on the Da Vinci Xi Surgical System. Surgical approaches were applied using four ports while the swine was in the left lateral position. The surgical procedure was accomplished in 70 min including positioning and preparation of robotic system (20 min), placement of ports and thoracic dissection and confirmation of level with the C-arm system (10 min), discectomy and cage insertion (15 min), control of cage position via the C-arm system and closure (10 min). This study showed the anterior thoracic approach with robotic surgery is safe and feasible with providing a wide working area and high image quality.  相似文献   
86.

Background Context

Red flags are questions typically ascertained by providers to screen for serious underlying spinal pathologies. The utility of patient-reported red flags in guiding clinical decision-making for spine care, however, has not been studied.

Purpose

The aim of this study was to quantify the sensitivity and specificity of patient-reported red flags in predicting the presence of serious spinal pathologies.

Study Design

This was a retrospective nested case-control study.

Patient Sample

This study consisted of 120 patients with International Classification of Diseases, Ninth Revision, Clinical Modification codes for spinal pathologies and 380 randomly selected patients, from a population of 4,313 patients seen at a large tertiary care spine clinic between October 9, 2013 and June 30, 2014.

Outcome Measures

The presence of patient-reported red flags and red flags obtained from medical records was verified for chart review. The spinal pathology (ie, malignancy, fractures, infections, or cauda equina syndrome) was noted for each patient.

Methods

The sensitivity and specificity of patient-reported red flags for detecting serious spinal pathologies were calculated from data obtained from the 500 patients. Youden's J was used to rank performance. Agreement between patient-reported red flags and those obtained from medical record review was assessed via Cohen's kappa statistic.

Results

“History of cancer” was the best performing patient-reported red flag to identify malignancy (sensitivity=0.75 [95% confidence intervals, CI 0.53–0.90], specificity=0.79 [95% CI 0.75–0.82]). The best performing patient-reported red flag for fractures was the presence of at least one of the following: “Osteoporosis,” “Steroid use,” and “Trauma” (sensitivity=0.59 [95% CI 0.44–0.72], specificity=0.65 [95% CI 0.60–0.69]). The prevalence of infection and cauda equina diagnoses was insufficient to gauge sensitivity and specificity. Red flags from medical records had better performance than patient-reported red flags. There was poor agreement between patient red flags and those obtained from medical record review.

Conclusions

Patient-reported red flags had low sensitivity and specificity for identification of serious pathologies. They should not be used in insolation to make treatment decisions, although they may be useful to prompt further probing to determine if additional investigation is warranted.  相似文献   
87.
88.

Aim

To compare the value of Procalcitonin (PCT) as a marker of surgical site infection to other inflammatory markers, including C-Reactive Protein (CRP), White Cell Count (WCC) and Erythrocyte Sedimentation Rate (ESR) in patients undergoing a number of spinal procedures. This study also aims to describe the biokinetic profile of the above-named markers in patients developing surgical site infection and those remaining infection-free post-operatively.

Methods

200 patients undergoing four routine elective spinal procedures were included for analysis. All patients had blood specimens taken at baseline, day 1, 2, 3, 4 and 5 post-operatively for analysis of PCT, CRP, ESR and WCC levels. All patients were monitored for early surgical site infection. Patients with other sources of infection in the early postoperative period were excluded.

Results

Procalcitonin was the most sensitive and specific marker for the detection of surgical site infection in the immediate post-operative period with sensitivity and specificity of 100% and 95.2% respectively. Although Procalcitonin is an inflammatory marker, extent of surgical physiological insult did not alter its biokinetics as opposed to the other inflammatory markers making it a valuable marker of infection.

Conclusion

Procalcitonin was found to be superior to the other inflammatory markers investigated in this study as a marker for early surgical site infection in patients undergoing spinal surgery.  相似文献   
89.
90.
BackgroundGranulicatella adiacens is a nutritional variant of streptococcus (NVS), which has been rarely reported as an etiologic agent in spondylodiscitis (SD).Material and methodsWe report a case of a 51-year-old male with from chronic low-back pain associated with right sciatica and ipsilateral monoparesis. Spinal MRI showed radiological signs on L1-L2 and L5-S1 discs consistent with SD. We also performed a systematic review of the pertinent literature in order to retrieve all the key information regarding microbiological and clinical features.ResultsIncluding our patients, seven cases with a mean age 56 ± 10.2 years were reported in English literature. Six patients were conservatively managed with antibiotic therapy (66%), whereas three with surgery in combination with antibiotics (33%). An endocarditis was associated in three cases, and a pacemaker infection in one. All patients received targeted antibiotic therapy resulting in a quick improvement of clinical symptoms with favorable outcome. Our case is the only with a skip spontaneous SD, which needed a surgical decompression due to the associated neurological symptoms.ConclusionsThis incidence of SD sustained by Granulicatella adiances could be underestimated due to their particular microbiological conditions requested for their cultures. However, this infection should be suspected in cases of culture-negative SD, especially when associated with endocarditis.  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