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   1582篇
  免费   71篇
  国内免费   11篇
耳鼻咽喉   54篇
儿科学   126篇
妇产科学   57篇
基础医学   129篇
口腔科学   107篇
临床医学   173篇
内科学   309篇
皮肤病学   69篇
神经病学   96篇
特种医学   77篇
外科学   225篇
综合类   23篇
预防医学   30篇
眼科学   33篇
药学   80篇
中国医学   3篇
肿瘤学   73篇
  2024年   2篇
  2023年   18篇
  2022年   18篇
  2021年   44篇
  2020年   21篇
  2019年   51篇
  2018年   37篇
  2017年   31篇
  2016年   56篇
  2015年   65篇
  2014年   85篇
  2013年   98篇
  2012年   123篇
  2011年   130篇
  2010年   77篇
  2009年   60篇
  2008年   125篇
  2007年   138篇
  2006年   129篇
  2005年   107篇
  2004年   94篇
  2003年   85篇
  2002年   35篇
  2001年   14篇
  2000年   6篇
  1999年   5篇
  1998年   4篇
  1997年   3篇
  1996年   1篇
  1995年   1篇
  1993年   1篇
排序方式: 共有1664条查询结果,搜索用时 62 毫秒
101.
OBJECTIVE: Intoxication is one of the most common causes of admissions to emergency department in pediatric age group. Incidence of iron poisoning gradually increased because of wide spread use of iron containing drugs. METHOD: In this report, we present five cases of iron ingestion who were admitted to our emergency department within a year. RESULT: Whole bowel irrigation in addition to gastric lavage with an iron dose of over 50 mg/kg as well as deferoxamine treatment for patients in whom clinical and laboratory indications are present. CONCLUSION: The prompt recognition and treatment of children with acute iron poisoning is the single and the most critical point for decreasing the morbidity and mortality associated with iron containing products.  相似文献   
102.
103.
104.
We conducted three prospective studies of Haemophilus influenzae in different groups of children. Pharyngeal swab samples were taken (i). from 1382 healthy infants and children between 0 and 10 years of age (group 1), attending well child clinics (n=438), day care centres (n=440) and elementary schools (n=504), and (ii). from 322 children aged 2-10 years (group 2), clinically diagnosed as having upper respiratory tract infection. Pharyngeal swab samples and sinus aspirates were obtained from 49 children between 2 and 9 years of age (group 3), clinically diagnosed as having sinusitis. H. influenzae was isolated in similar rates from 315 (22.7%) of children in group 1, 72 (22.3%) of children in group 2 and 12 (24.4%) of children in group 3. Serotype b comprised 7, 5.2 and 2% of all H. influenzae isolates for group 1, 2 and 3, respectively. Production of beta-lactamase was detected in 1.0% of H. influenzae type b isolates in group 1, 1.2 and 6.1% of all isolates in group 2 and 3, respectively. There were no beta-lactamase negative ampicillin-resistant strains.  相似文献   
105.
OBJECTIVE: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. METHODS: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. RESULTS: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. CONCLUSION: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia.  相似文献   
106.
Novel benzoylalanine-derived ketoamides were prepared and evaluated for calpain I inhibition. Derivatives carrying vinylbenzyl amino residues in the P(2)-P(3) region inhibited calpain in nanomolar concentrations and thus represent a novel class of nonpeptidic calpain inhibitors. Selected examples exhibited an improved pharmacokinetic profile including improved water-solubility and metabolic stability. In particular, these calpain inhibitors showed oral bioavailability in rats as demonstrated by N-(1-benzyl-2-carbamoyl-2-oxoethyl)-2-[E-2-(4-diethylaminomethylphenyl)ethen-1-yl]benzamide (5d). The closely related derivative N-(1-carbamoyl-1-oxohex-1-yl)-2-[E-2-(4-dimethylaminomethylphenyl)-ethen-1-yl]benzamide (5b) was evaluated for neuroprotective efficacy after experimental traumatic brain injury in a fluid percussion model in rats. When administered after injury, 5b reduced the number of damaged neurons by 41%, and this result would be in line with the suggested neuroprotective efficacy of calpain inhibition.  相似文献   
107.
Epididymis and vas deferens form part of the male internal genital tract and are dependent on androgens for their growth and development. To better understand the molecular action of androgens during male genital tract development, protein expression profiles were generated using two-dimensional gels, for rat epididymides and vasa deferentia isolated on embryonic days (E) 17-21. Proteins that were differentially expressed between E17 and E21 were cut from the gels, digested into tryptic peptides and analyzed on a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer. Using this approach, 20 proteins could be identified that were regulated in time and were categorized into cytoskeletal proteins, nuclear proteins, transport proteins, chaperones, and enzymes (mainly glycolytic). Furthermore, epididymides and vasa deferentia isolated on E19 were cultured in vitro in the absence or presence of 10 nm of the synthetic androgen R1881, for 9, 24, and 48 h. Under these conditions, regulation and posttranslational modification were observed for glyceraldehyde 3-phosphate dehydrogenase, triosephosphate isomerase, heterogeneous nuclear ribonucleoprotein A2/B1 and heterogeneous nuclear ribonucleoprotein A3, similar to the observed changes in vivo. In addition, posttranslational modification of RhoGDI1 (also named RhoGDIalpha) was found in response to androgen. Androgen-induced posttranslational modification of RhoGDI1 and glycolytic enzymes may be an important functional link between signaling pathways and cytoskeletal rearrangements in control of growth and development of the male internal genital tract.  相似文献   
108.
109.
Abstract – There are few reports on treatment of necrotic pulps with mineral trioxide aggregate (MTA) for apexification. Five immature teeth with necrotic pulps were treated with the use of an apical plug of MTA for apexification. All teeth were central incisors that had premature interruption of root development caused by a previous trauma. According to the treatment protocol, the root canals were rinsed with 5% NaOCl; then calcium hydroxide paste was placed in the canals for 1–6 weeks. The apical portion of the canals were filled with MTA. The rest of the canals were obturated with lateral condensation of the gutta‐percha applied with a canal sealer. At 6 months, 1 year and 2 year follow‐up periods the clinical and radiographic appearance of the teeth showed the resolution of the periapical lesions and continued root end development in all except in the one case in which the MTA was extruded out the apex. MTA can be considered a very effective option for apexification with the advantage of reduced treatment time, good sealing ability and high biocompatibility.  相似文献   
110.
Congenital dermal sinus of the cervical spine in an adult.   总被引:1,自引:0,他引:1  
Congenital dermal sinuses are epithelium-lined tracts that extend from an opening in the skin through deeper tissues. Most dorsal congenital dermal sinuses are located in the lumbosacral area; a cervical location is unusual. This report describes a 24-year-old woman who presented with neck pain of 6 months' duration. A dimple in the skin over her cervical spine and a stunted right foot (0.5 cm shorter than the left) were detected on physical assessment. Neurological examination revealed increased deep tendon reflexes in her lower extremities. Magnetic resonance imaging showed a dermal sinus extending from the dimple site to the spinal cord near the C4-C5 vertebrae. Laminectomies were performed at C3-C4 and the tract was totally excised. The patient's neck pain completely resolved and her deep tendon reflexes were normal at 12 months after surgery. Tethered spinal cord alone does not necessarily demand surgery; however, if a congenital dermal sinus is present then surgery is indicated to prevent spinal infection. Even if there are no neurological symptoms, the tract must be surgically removed and the cord must be fully released to prevent future infectious or neurological complications.  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