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   1260篇
  免费   80篇
耳鼻咽喉   15篇
儿科学   51篇
妇产科学   26篇
基础医学   126篇
口腔科学   16篇
临床医学   73篇
内科学   189篇
皮肤病学   89篇
神经病学   156篇
特种医学   30篇
外科学   184篇
综合类   55篇
一般理论   1篇
预防医学   80篇
眼科学   55篇
药学   120篇
中国医学   1篇
肿瘤学   73篇
  2023年   7篇
  2022年   23篇
  2021年   39篇
  2020年   17篇
  2019年   29篇
  2018年   44篇
  2017年   28篇
  2016年   35篇
  2015年   38篇
  2014年   50篇
  2013年   64篇
  2012年   87篇
  2011年   87篇
  2010年   51篇
  2009年   40篇
  2008年   72篇
  2007年   45篇
  2006年   53篇
  2005年   37篇
  2004年   46篇
  2003年   32篇
  2002年   39篇
  2001年   44篇
  2000年   39篇
  1999年   22篇
  1998年   10篇
  1997年   10篇
  1996年   7篇
  1995年   5篇
  1992年   10篇
  1991年   13篇
  1990年   14篇
  1989年   22篇
  1988年   11篇
  1987年   15篇
  1986年   10篇
  1985年   16篇
  1984年   10篇
  1983年   8篇
  1981年   8篇
  1980年   8篇
  1979年   7篇
  1978年   8篇
  1976年   6篇
  1975年   7篇
  1973年   9篇
  1972年   6篇
  1971年   8篇
  1970年   8篇
  1969年   7篇
排序方式: 共有1340条查询结果,搜索用时 15 毫秒
81.
82.
83.
The development of techniques and new tools for environmental acoustic measurements has opened up new ways and means to determine the source location, source ranking and energy flow path. The new tools posses versatile probes for different applications, better digital signal processing facilities and data presentation for sound pressure measurements--the quantity we hear, sound power measurements--the quantity emitted from a source, and the sound intensity measurements--the quantity of propogated sound power. The paper reports the results of real time sound intensity measurement carried out in an industrial complex with a portable sound intensity analyzer equipped with 1/3 octave filters and a dual microphone remote control probe for real time analysis. Extensive sound intensity measurement in the Power Plant, Ammonia Compressor House and Urea Compressor House have been carried out. The results are useful for sound power determination of various sources.  相似文献   
84.
OBJECTIVES: We report the frequency of usage, patient demographics, and outcomes in children treated with continuous venovenous hemofiltration (CVVH) in three pediatric intensive care units (PICUs), with one unit providing combined extracorporeal membrane oxygenation (ECMO) and CVVH. DESIGN: Prospective database analysis. SETTING: Three regional PICUs in the Trent Haemofiltration Network with two general PICUs admitting 450-500 patients annually and the other providing regional cardiac support and a supraregional service for ECMO (600-650 admissions annually with 50 ECMO patients). PATIENTS: Children who underwent CVVH alone or in combination with ECMO or other therapies between January 2000 and December 2002. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 115 children (58 male) treated, with a median age of 18 months (range 1 day to 17 yrs) and median weight of 12 kg (range 1.8-119 kg). In the two PICUs without ECMO, CVVH was undertaken in 2.5% of admissions annually compared with 3% of annual admissions to the PICU with an ECMO service. Fifty-five patients received CVVH alone (group 1), while 53 patients underwent CVVH in conjunction with ECMO (group 2). In addition, five patients received plasmafiltration followed by CVVH, and two patients were treated with combined CVVH and molecular adsorbents recirculating system. Mean duration of therapy in group 1 was 142 hrs (1-840 hrs) and in group 2,231 hrs (3-1104 hrs). Overall patient survival was 43% with 29 of 55 (53%) CVVH patients surviving and 18 of 53 (34%) of those treated with ECMO plus CVVH. CONCLUSIONS: Performing CVVH in a heterogeneous population with large age and weight ranges poses significant clinical and technical challenges. The low frequency of CVVH use, as well as the use of other extracorporeal therapies, also raises problems with maintaining nursing skills. Objective clinical and biochemical markers for commencing CVVH alone or in combination with ECMO remain to be defined.  相似文献   
85.
Hyperpigmentation is a common disorder of the skin, particularly in brown-skinned patients. Melasma is a common cause of facial hyperpigmentation and can be resistant to treatment. A combination of topical creams and gels, chemical peels, and sunscreens may be necessary for significant improvement. Erythema dyschromicum perstans is a dermal pigmentation seen on the trunk and proximal extremities, most commonly presenting in dark-skinned Hispanics. Drug-induced and postinflammatory hyperpigmentation may last for many months after the offending drug or dermatitis has been eliminated. These disorders, including their management, is reviewed in this article.  相似文献   
86.
Purpose: The present study was conducted to investigate the efficacy and toxicity of a cisplatin and 5fluorouracil (5FU) combination in previously treated advanced breast cancer.Methods: Thirtysix women with recurrent metastatic breast cancer were entered on a phase II study of 5FU 1000mg/m2/day given intravenously as a continuous infusion on days 1–3 and cisplatin 30mg/m2/day given intravenously over 1h on days 2–4, repeated every 21 days. All subjects had received one previous chemotherapy regimen for metastatic disease and either progressed during treatment or relapsed after responding to previous chemotherapy. Fourteen patients had also received previous adjuvant chemotherapy, 17 patients had previous radiation therapy, and 29 patients had previous hormonal therapy.Results: Among 32 responseevaluable patients, there were 10 partial remissions (31%) and 1 complete remission (3%), with an overall objective response rate of 34%. Median duration of response was 4 months. Median survival was 10.5 months for responders and 9.5 months for the entire group. Toxicity was mild to moderate in most patients. Overall twelve patients experienced grade 3 toxicity (10 hematologic, 1 mucositis, and 2 nausea). There were no grade 4 or 5 toxicities.Conclusion: Infusional cisplatin and 5FU is a well tolerated and active regimen in women with previously treated advanced breast cancer.  相似文献   
87.
The mutagenic potential of three exocyclic DNA adducts was studied in Escherichia coli and simian kidney cells by incorporating them into single-stranded DNA. Differences in the mutagenic potency of the adducts were observed between hosts: 1,N6-ethenodeoxyadenosine and 3,N4-ethenodeoxycytidine were more mutagenic in simian cells, whereas 1,N2-(1,3-propan-1,3-diyl)-2'-deoxyguanosine was more mutagenic in E. coli. To investigate the cellular response to DNA adducts, a double-stranded DNA vector system was developed. Use of this system showed that 1,N6-ethenodeoxyadenosine blocks DNA synthesis strongly, and DNA synthesis past this adduct was highly accurate in E. coli. The blockage of DNA synthesis was overcome in an error-free manner by the recombination repair mechanism (daughter-strand gap repair).  相似文献   
88.
89.
A case of a 7-year-old boy who presented with a pontine space occupying lesion and had typical findings of acrodysostosis is presented. His 9-year-old sister and 5-year-old brother also showed similar skeletal features. His mother had short stature and a similar facial and limb features but normal radiographs, whereas the father had short stature but normal limbs and face. The pedigree of this family is suggestive of a syndrome caused by a dominant gene. The rarity of this disorder with an interesting pedigree chart prompted us to present this case and highlight the important diagnostic features and inheritance of this condition.  相似文献   
90.
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