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   8505篇
  免费   561篇
  国内免费   57篇
耳鼻咽喉   59篇
儿科学   193篇
妇产科学   122篇
基础医学   802篇
口腔科学   170篇
临床医学   756篇
内科学   2156篇
皮肤病学   80篇
神经病学   1176篇
特种医学   278篇
外科学   1559篇
综合类   21篇
一般理论   1篇
预防医学   344篇
眼科学   205篇
药学   453篇
中国医学   13篇
肿瘤学   735篇
  2023年   110篇
  2022年   94篇
  2021年   350篇
  2020年   230篇
  2019年   300篇
  2018年   308篇
  2017年   236篇
  2016年   271篇
  2015年   285篇
  2014年   412篇
  2013年   494篇
  2012年   760篇
  2011年   707篇
  2010年   362篇
  2009年   362篇
  2008年   541篇
  2007年   528篇
  2006年   544篇
  2005年   450篇
  2004年   406篇
  2003年   357篇
  2002年   307篇
  2001年   61篇
  2000年   52篇
  1999年   58篇
  1998年   33篇
  1997年   32篇
  1996年   38篇
  1995年   28篇
  1994年   33篇
  1993年   28篇
  1992年   39篇
  1991年   37篇
  1990年   21篇
  1989年   34篇
  1988年   19篇
  1987年   15篇
  1986年   20篇
  1985年   17篇
  1984年   27篇
  1983年   17篇
  1982年   13篇
  1981年   17篇
  1980年   8篇
  1979年   12篇
  1978年   5篇
  1977年   5篇
  1975年   5篇
  1974年   10篇
  1973年   5篇
排序方式: 共有9123条查询结果,搜索用时 31 毫秒
1.
2.

Background

Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.

Materials and methods

Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.

Results

EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.

Conclusion

This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy.  相似文献   
3.
4.
PurposeTo compare hepatic hypertrophy in the contralateral lobe achieved by unilobar transarterial radioembolization (TARE) versus portal vein embolization (PVE) in a swine model.MethodsAfter an escalation study to determine the optimum dose to achieve hypertrophy after unilobar TARE in 4 animals, 16 pigs were treated by TARE (yttrium-90 resin microspheres) or PVE (lipiodol/n-butyl cyanoacrylate). Liver volume was calculated based on CT before treatment and during 6 months of follow-up. Independent t-test (P < .05) was used to compare hypertrophy. The relationship between hypertrophy after TARE and absorbed dose was calculated using the Pearson correlation.ResultsAt 2 and 4 weeks after treatment, a significantly higher degree of future liver remnant hypertrophy was observed in the PVE group versus the TARE group, with a median volume gain of 31% (interquartile range [IQR]: 16%–66%) for PVE versus 23% (IQR: 6%–36%) for TARE after 2 weeks and 51% (IQR: 47%–69%) for PVE versus 29% (IQR: 20%–50%) for TARE after 4 weeks. After 3 and 6 months, hypertrophy converged without a statistically significant difference, with a volume gain of 103% (IQR: 86%–119%) for PVE versus 82% (IQR: 70%–96%) for TARE after 3 months and 115% (IQR: 70%–46%) for PVE versus 86% (IQR: 58%–111%) for TARE after 6 months. A strong correlation was observed between radiation dose (median 162 Gy, IQR: 139–175) and hypertrophy.ConclusionsPVE resulted in rapid hypertrophy within 1 month of the procedure, followed by a plateau, whereas TARE resulted in comparable hypertrophy by 3–6 months. TARE-induced hypertrophy correlated with radiation absorbed dose.  相似文献   
5.
Transformation is one of the mechanisms of acquisition of foreign genetic material leading to the emergence of multidrug resistant (MDR) bacteria. Recently, human serum albumin (HSA) was shown to specifically increase transformation frequency in the nosocomial pathogen Acinetobacter baumannii. To further assess the relevance of HSA as a possible modulator of A. baumannii transformation in host-pathogen interactions, in this work we examined the effect of different human fluids. We observed a significant increase in transformation frequencies in the presence of pleural fluid, whole blood cells and liquid ascites, and to a lesser extent with urine. The observed effects correlate with both HSA and bacterial content found in the assayed patient fluids. Taken together, these results are in agreement with our previous findings that highlight HSA as a possible host signal with the ability to trigger natural transformation in A. baumannii.  相似文献   
6.

Background

Total ankle replacement (TAR) represents an alternative to fusion for the treatment of end-stage ankle osteoarthritis. The aim of the present study was to retrospectively assess the frequency of infections between TARs with anterior and lateral transfibular approach at 12-months follow-up.

Methods

81 TARs through an anterior approach and 69 TARs through a lateral approach were performed between May 2011 and July 2015. We compared surgical time and tourniquet time, as well as superficial and deep infections frequency during the first 12 postoperative months.

Results

In the anterior approach group, there were 3 (3.7%) deep infections and 4 (4.9%) superficial wound infections. In the lateral approach group, there were 1 (1.4%) deep infection and 2 superficial wound infections (2.9%). There were not statistically significant differences between the groups. There was a significant difference between anterior approach (115 minutes) and lateral approach group (179 minutes) in terms of surgical time (P < 0.001).

Conclusions

The frequency of superficial and deep periprosthetic infections during the first postoperative year was not significantly different in the lateral approach group compared to the anterior approach group, despite the significantly longer surgical time in the lateral transfibular approach group.  相似文献   
7.

Background

In colorectal cancer liver metastases (CRCLM), bevacizumab-based neoadjuvant strategies provide increased pathologic response. We aimed at assessing the activity of perioperative capecitabine, oxaliplatin, irinotecan, and bevacizumab (COI-B regimen) in patients with potentially resectable CRCLM, and investigating biomarkers for early prediction of pathologic response.

Patients and Methods

This was a single-center phase II study enrolling patients with liver-limited, borderline resectable disease and/or high-risk features. Patients received 5 preoperative and 4 postoperative cycles of biweekly COI-B (irinotecan 180 mg/m2 and bevacizumab 5 mg/Kg on day 1, oxaliplatin 85 mg/m2 on day 2, and capecitabine 1000 mg/m2 twice a day on days 2 to 6). The primary endpoint was pathologic response rate in the intention-to-treat population. A Simon 2-stage design was adopted to detect an increase from 30% to 50% with a power of 90%. Dynamic imaging biomarkers (early tumor shrinkage [ETS], deepness of response, maximum standardized uptake volume [SUVmax]/regression index) and next generation sequencing data were explored as surrogates.

Results

From June 2013 to March 2017, 46 patients were enrolled. Pathologic response was achieved in 63% patients (endpoint met), and responders achieved significantly better survival outcomes with respect to non-responders. The most frequent grade 3/4 adverse events were diarrhea and neutropenia (8.7%) in the preoperative phase and thromboembolic events (5.9%) in the postoperative phase. ETS and lower SUV-2 were significantly associated with pathologic response.

Conclusion

The COI-B regimen is a feasible and highly active perioperative strategy in patients with molecularly unselected, potentially resectable CRCLM. ETS and SUV-2 have a promising role as imaging-based biomarkers for pathologic response.  相似文献   
8.
9.
10.
Kidney transplant is currently the elective treatment of choice for end-stage renal disease. Laparoscopic living donor nephrectomy (LLDN) has substantial advantages over open nephrectomy. Chylous ascites (CA) is a rare surgical complication after the LLDN; there are few reports in the literature.We present a case report of a 58-year-old woman who started CA on the 21st day post operation. The recommended initial therapeutic approach to suspend the fat in the diet and place percutaneous drainage was not enough. It was decided to jointly introduce fasting and total parenteral nutrition with the administration of octreotide, resolving the complication completely in 15 days with no need for the patient to undergo surgery.The conservative management, during the first 4 to 8 weeks after the diagnosis is the best option. Surgery is generally recommended if conservative management fails.The prevalence of CA varied between 0% and 6.2% of LLDNs. In our experience of 87 LLDNs, we only presented 1.15% for this complication. There are 62 cases reported in the international literature. The mean presentation was 14 days after LLDN. All patients underwent conservative treatment, and only 15 patients (24%) went to surgery after the failure of conservative management.It would be highly useful, considering the disparity of the prevalence, if the bibliographic reports detail what hemostatic and sealing techniques are used in an LLDN. In this way it would be possible to identify which factor affects a complication like this one.  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