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   9297篇
  免费   535篇
  国内免费   153篇
耳鼻咽喉   475篇
儿科学   57篇
妇产科学   850篇
基础医学   570篇
口腔科学   611篇
临床医学   1057篇
内科学   480篇
皮肤病学   109篇
神经病学   85篇
特种医学   479篇
外科学   1806篇
综合类   1421篇
预防医学   446篇
眼科学   54篇
药学   564篇
  5篇
中国医学   266篇
肿瘤学   650篇
  2024年   19篇
  2023年   127篇
  2022年   317篇
  2021年   366篇
  2020年   340篇
  2019年   325篇
  2018年   304篇
  2017年   324篇
  2016年   326篇
  2015年   296篇
  2014年   669篇
  2013年   575篇
  2012年   571篇
  2011年   584篇
  2010年   502篇
  2009年   519篇
  2008年   498篇
  2007年   486篇
  2006年   445篇
  2005年   368篇
  2004年   315篇
  2003年   238篇
  2002年   194篇
  2001年   174篇
  2000年   157篇
  1999年   135篇
  1998年   102篇
  1997年   92篇
  1996年   88篇
  1995年   78篇
  1994年   69篇
  1993年   43篇
  1992年   44篇
  1991年   35篇
  1990年   29篇
  1989年   24篇
  1988年   21篇
  1987年   30篇
  1986年   18篇
  1985年   31篇
  1984年   15篇
  1983年   11篇
  1982年   12篇
  1981年   14篇
  1980年   12篇
  1979年   13篇
  1978年   13篇
  1976年   6篇
  1973年   5篇
  1972年   2篇
排序方式: 共有9985条查询结果,搜索用时 125 毫秒
1.
Patients undergoing sentinel node biopsy (SLNB) for early oral squamous cell carcinoma (OSCC) who harbour occult metastases (pN+ve) may be at greater risk of mortality due to prolonged overall treatment times than those identified as pN+ve on elective neck dissection (ELND). A retrospective comparative survival analysis was therefore undertaken to test this hypothesis. Patients were identified from the South Glasgow multidisciplinary team (MDT) database. Group 1 comprised 38 patients identified as pN+ve, or who were false negative, on sentinel lymph node biopsy (SLNB). Group 2 comprised 146 patients staged pN+ve on ELND. The groups were compared with the Kaplan Meier method and Cox proportional hazards model. In addition, a matched-pair analysis was performed. A unique and specifically designed algorithm was deployed to optimise the pairings. No difference in disease-specific or overall survival was found between the groups. Patients undergoing SLNB as the initial neck staging modality in early OSCC and are identified as pN+ve do not appear to be at a survival disadvantage compared with those staged with ELND.  相似文献   
2.
3.
ObjectivesMap regional lymph node metastases for lateralized oral cavity squamous cell carcinoma (OCSCC) and evaluate factors associated with regional metastases and recurrence.Materials and methodsRetrospective cohort study of 715 patients with lateralized OCSCC surgically treated in 1997–2011. Analysis was performed using log-rank, Kaplan-Meier, and multivariable logistic and Cox regression.ResultsRegional metastases were identified in ipsilateral levels IIA (24%), IB (18%), III (13%), V (9%), IV (7%), IA (2%) and IIB (1%) and the contralateral neck (3%). Lymphovascular invasion (LVI) (Hazard Ratio [HR] 2.2, 95% Confidence Interval [CI] 1.2–3.9) and T category (T3 vs. T1: HR 4.1, 95% CI 1.9–9.3; T4 vs. T1: HR 2.3, 95% CI 1.2–4.3) were associated with regional metastases. Most (71%) isolated regional metastatic recurrences were in undissected levels of the neck, including 58% in levels IV and V. Tumors of the hard palate (HR 4.3, 95% CI 1.2–16.1), upper alveolus (HR 3.2, 95% CI 1.0–4.7) or with LVI (HR 2.0, 95% CI 1.0–3.9) were associated with isolated regional recurrence. For upper alveolar/hard palate tumors, depth of invasion (DOI) ≥4 mm (P = .003) and LVI (P = .04) were associated with regional metastases.ConclusionsFor lateralized OCSCC, elective neck dissection of level IIB or the contralateral neck may rarely be needed, but additional surgical or radiation treatment of levels IV and V may be considered based on patient risk factors, including T category 3–4 or LVI. For upper alveolar/hard palate tumors, DOI ≥4 mm is an appropriate threshold for elective neck dissection.  相似文献   
4.
AimsTo demonstrate a new laparoscopic sign “Sharma's Parachute sign” in abdominopelvic tuberculosis in women with infertility.MethodsA total of 104 women who were diagnosed to have abdominopelvic tuberculosis, on endometrial sampling or on laparoscopy were enrolled in this ongoing study on tuberculosis in infertility. A new laparoscopic “Sharma's parachute sign” was looked for in these cases on laparoscopy.ResultsThe mean age, pairty and duration of infertility was 27.6 years, 0.58 and 4.1 years respectively. Menstrual dysfuction were common especially hypomenorrhoea (34.61%), oligomenorrhoea (36.53%) along with constitutional symptoms and abdomino pelvic pain or lump. Diagnosis of abdominopelvic tuberculosis was made by identification of acid fast bacilli (AFB) on microscopy or culture of endometrial aspirate or peritoneal biopsy or positive gene Xpert or positive polymerase chain reaction (PCR) or histopathological demonstration of epithelioid granuloma on endometrial or peritoneal biopsy, various laparoscopic findings on pelvic and abdominal organs were tubercles and shaggy areas (white deposits, caseous nodules encysted ascites, abdominal and pelvic adhesions, tubal findings (hydrosalpinx, pyosalpinx, beaded or calcified tubes). A new “Sharma's parachute sign”in which ascending colon was totally adherent to anterior abdominal wall with its mesocolon looking like an open parachute with small caseous nodule was seen in 11 (10.5%) cases.ConclusionDiagnostic laparoscopy is an important investigation for abdominopelvic tuberculosis showing various adhesions including new parachute sign.  相似文献   
5.
6.
7.
IntroductionLymph node yield (LNY) in neck dissection has been identified as a prognostic factor in oral cavity cancer. The purpose of this study was to investigate the impact of additional use of optical imaging on LNY in therapeutic ND in oral cancer.MethodsConsecutive patients with oral squamous cell carcinoma with clinical neck metastasis planned for primary tumor resection were randomized to conventional neck dissection or near-infrared fluorescence (NIRF)-guided neck dissection, respectively. In the intervention group, patients were injected with ICG-Nanocoll prior to surgery. Intraoperatively, an optical hand-held camera system was used for lymph node identification. Also, NIRF imaging of the neck specimen was performed, and optical signals were pinned with needle markings to guide the pathological examination. The endpoint of the study was LNY per neck side in levels Ib-III.Results31 patients were included with 18 neck sides in the control group and 18 neck sides in the intervention group for evaluation. During NIRF-guided ND, individual lymph nodes could be identified by a bright fluorescent signal and individual tumor-related drainage patterns could be observed in the neck. The LNY in the intervention group was significantly higher compared to the control group (p = 0.032) with a mean of 24 LN (range: 12–33 LN in levels Ib-III compared to 18 LN (range: 10–36 LN) in the control group, respectively.ConclusionsNIRF-guided ND significantly improved the nodal yield compared to the control group. Intraoperative real-time optical imaging enabled direct visualization of tumor-related drainage patterns within the neck lymphatics.  相似文献   
8.
9.

Background

Available models for predicting lymph node invasion (LNI) in prostate cancer (PCa) patients undergoing radical prostatectomy (RP) might not be applicable to men diagnosed via magnetic resonance imaging (MRI)-targeted biopsies.

Objective

To assess the accuracy of available tools to predict LNI and to develop a novel model for men diagnosed via MRI-targeted biopsies.

Design, setting, and participants

A total of 497 patients diagnosed via MRI-targeted biopsies and treated with RP and extended pelvic lymph node dissection (ePLND) at five institutions were retrospectively identified.

Outcome measurements and statistical analyses

Three available models predicting LNI were evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision curve analyses. A nomogram predicting LNI was developed and internally validated.

Results and limitations

Overall, 62 patients (12.5%) had LNI. The median number of nodes removed was 15. The AUC for the Briganti 2012, Briganti 2017, and MSKCC nomograms was 82%, 82%, and 81%, respectively, and their calibration characteristics were suboptimal. A model including PSA, clinical stage and maximum diameter of the index lesion on multiparametric MRI (mpMRI), grade group on targeted biopsy, and the presence of clinically significant PCa on concomitant systematic biopsy had an AUC of 86% and represented the basis for a coefficient-based nomogram. This tool exhibited a higher AUC and higher net benefit compared to available models developed using standard biopsies. Using a cutoff of 7%, 244 ePLNDs (57%) would be spared and a lower number of LNIs would be missed compared to available nomograms (1.6% vs 4.6% vs 4.5% vs 4.2% for the new nomogram vs Briganti 2012 vs Briganti 2017 vs MSKCC).

Conclusions

Available models predicting LNI are characterized by suboptimal accuracy and clinical net benefit for patients diagnosed via MRI-targeted biopsies. A novel nomogram including mpMRI and MRI-targeted biopsy data should be used to identify candidates for ePLND in this setting.

Patient summary

We developed the first nomogram to predict lymph node invasion (LNI) in prostate cancer patients diagnosed via magnetic resonance imaging-targeted biopsy undergoing radical prostatectomy. Adoption of this model to identify candidates for extended pelvic lymph node dissection could avoid up to 60% of these procedures at the cost of missing only 1.6% patients with LNI.  相似文献   
10.
PurposeInjuries of both pelvic ring and acetabulum as rare very few articles are available in literature. There are no set protocols in defining the injury let alone defining early and definitive management strategies. This article is an attempt to encompass all available data to give us guidelines in managing these injuries.MethodsAn extensive literature review was carried out on PubMed/Medline, google scholar and Embase databases was done with the eligibility criteria of 1) Case series with a minimum of 20 cases. 2) The patient’s outcome reported. 3) Full article available. 4) Article in English. 5) Minimum Jadad score of 3. As per PRISMA guidelines the search was done and gradually filtered down to relevant articles which were 8 in number.ResultsThe incidence of these injuries range from 5 to 16%. The transverse acetabular fracture pattern is the commonest followed by associated both column fractures. There is equal propensity of Anteroposterior compression and lateral compression injuries. The injury mechanism appears to transmitted lateral force from the greater trochanter inwards with an implosion injury causing acetabular and pelvic injury as a continuum. The initial management is similar to managing pelvic ring injuries with focus on patient resuscitation, hemodynamic stabilization and temporary stabilization. The injury severity score and the mortality rates are comparable to isolated unstable pelvic ring injuries. Definitive management focuses on fixing the posterior pelvic ring first followed by the acetabular fracture and then the anterior pelvic ring. The displacement rates and outcome is worse than isolated acetabular injuries or pelvic injuries.ConclusionCombined Pelvic and acetabular injuries are complex injuries which need to be managed initially as we manage pelvic injury and later as we fix as an acetabular fracture meticulously.  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