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141.
Isolation of macrophages (Hofbauer cells) from human term placenta and their prostaglandin E2 and thromboxane production 总被引:2,自引:0,他引:2
Wetzka B; Clark DE; Charnock-Jones DS; Zahradnik HP; Smith SK 《Human reproduction (Oxford, England)》1997,12(4):847-852
Placental macrophages (Hofbauer cells) are located close to trophoblast
cells and fetal capillaries, which makes them ideal candidates for
involvement in regulatory processes within the villous core. Their
production of various cytokines and prostaglandin (PG) synthesizing enzymes
has previously been shown immunohistochemically. Hofbauer cells were
isolated from human placenta after term deliveries by Ficoll and Percoll
gradient centrifugation. Remaining trophoblast cells were removed with
anti-epidermal growth factor (EGF)-receptor-coated Dynabeads followed by
differential adherence. The identity of isolated cells was investigated by
immunohistochemistry with anti-CD68, which showed that >90% cells were
positive. After a 36 h recovery period in either 20% O2 or 5% O2, fresh
medium was applied and PGE2 and thromboxane (TXA2) production analysed by
enzyme immunoassay at 4, 8, and 24 h. PGE2 and TXA2 were both produced by
placental macrophages with PGE2 synthesis being predominant. Concentrations
of both could be stimulated by lipopolysaccharide with maximum effect after
24 h. Culture in low oxygen caused decreased PGE2 concentrations, whereas
TXA2 production remained unchanged. In conclusion, the presented isolation
protocol allows further study of Hofbauer cell function. This study also
presents novel findings regarding the prostaglandin production of term
Hofbauer cells under normal and hypoxic conditions.
相似文献
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143.
SUMMARY It has been suggested that two types of insomnia, sleep onset insomnia and early morning awakening insomnia, may be caused by delays and advances respectively of circadian rhythms. Evidence supports the circadian rhythm phase delay of sleep onset insomniacs. The present study investigated the phase timing of circadian rhythms of early morning awakening insomniacs compared with a group of age matched good sleepers. A 24-h bed rest laboratory session was used to evaluate the endogenous core body temperature and urinary melatonin rhythms. Objective and subjective sleepiness were also measured every 30 min across the session with 10 min multiple sleep latency tests and Stanford Sleepiness Scale. Maximum and minimum phases of each individual's rhythm were identified using two-component cosine curve fitting. Compared with the good sleepers, the insomniacs had significant phase advances of 2 4 h for the temperature and melatonin rhythms. However, the 0-4 h advances of the sleepiness rhythms were not significant. This latter unexpected result was explained on the basis of variability of sleepiness measures. It was suggested that early morning awakening insomnia arises from phase advanced circadian rhythms which evoke early arousal's from sleep. 相似文献
144.
硬膜外注射一定量液体冲击治疗腰椎术后近期疼痛26例 总被引:1,自引:0,他引:1
0 引言 我科近年来 ,对腰椎手术后近期出现疼痛患者 ,行硬膜外注射大容量等渗盐水 ,利多卡因及地塞米松治疗 ,取得良好效果 .1 对象和方法1.1 对象 患者 2 6 (男 2 2 ,女 4)例 ,年龄 38~ 5 2岁 . 2 5例术前诊断为椎间盘突出症 ,行椎间盘摘除术 ,1例为椎管狭窄 ,行椎管减压术 . 2 1例术后 7d左右出现术前症状 ,并逐渐加重 ,其疼痛症状超过术前 ,经 X线检查未见特殊病变 . 4例术后 10 d以上出现术前症状 ,但症状比术前略有改善 ,X线检收稿日期 :2 0 0 0 -0 5 -31; 修回日期 :2 0 0 0 -0 8-2 6作者简介 :张捍平 (196 4-) ,男 (汉族 ) ,… 相似文献
145.
Jurgen EM Mourik Mark Lubberink Floris HP van Velden Reina W Kloet Bart NM van Berckel Adriaan A Lammertsma Ronald Boellaard 《Journal of cerebral blood flow and metabolism》2010,30(2):381-389
The aim of this study was to validate in vivo the accuracy of a reconstruction-based partial volume correction (PVC), which takes into account the point spread function of the imaging system. The NEMA NU2 Image Quality phantom and five healthy volunteers (using [11C]flumazenil) were scanned on both HR+ and high-resolution research tomograph (HRRT) scanners. HR+ data were reconstructed using normalization and attenuation-weighted ordered subsets expectation maximization (NAW-OSEM) and a PVC algorithm (PVC-NAW-OSEM). HRRT data were reconstructed using 3D ordinary Poisson OSEM (OP-OSEM) and a PVC algorithm (PVC-OP-OSEM). For clinical studies, parametric volume of distribution (VT) images were generated. For phantom data, good recovery was found for both OP-OSEM (0.84 to 0.97) and PVC-OP-OSEM (0.91 to 0.98) HRRT reconstructions. In addition, for the HR+, good recovery was found for PVC-NAW-OSEM (0.84 to 0.94), corresponding well with OP-OSEM. Finally, for clinical data, good correspondence was found between PVC-NAW-OSEM and OP-OSEM-derived VT values (slope: 1.02±0.08). This study showed that HR+ image resolution using PVC-NAW-OSEM was comparable to that of the HRRT scanner. As the HRRT has a higher intrinsic resolution, this agreement validates reconstruction-based PVC as a means of improving the spatial resolution of the HR+ scanner and thereby improving the quantitative accuracy of positron emission tomography. 相似文献
146.
ObjectiveTo determine the status of Wolbachia subgroup and phylogenetic relationships in Indian mosquitoes.MethodsRecently we reported Wolbachia infection in eight out of twenty field-caught mosquito species of India, using wsp specific primers. DNA extracted from these mosquito species were used for PCR amplification and sequencing.ResultsWolbachia A harboured in Aedes albopictus and Culex gelidus belongs to the subgroup AlbA whereas Wolbachia B harboured in Aedes albopictus and Culex quinquefasciatus belongs to the subgroup Pip and of Culex vishnui belongs to subgroup Con. However, Wolbachia harboured in Armigeres subalbatus, Armigeres kesseli, Culex sitiens and Toxorhynchites splendens could not be placed into any known subgroup and may represent other unknown strains of Wolbachia. Our phylogenetic analysis revealed eight novel Wolbachia strains, four in the A group and four in the B group. Most of the Wolbachia strains present in Indian mosquitoes belong to the Albo, Pip and Con groups.ConclusionsThe similarities and differences between Wolbachia strains infecting different mosquito species are fundamental for estimating how easily mosquitoes acquire new infections. 相似文献
147.
Laubert T Hildebrand P Roblick UJ Kraus M Esnaashari H Wellhöner P Bruch HP 《European journal of medical research》2010,15(9):390-396
Purpose
Diverticula of the esophagus represent a rare pathological entity. Distinct classifications of the disease imply different surgical concepts. Surgery should be reserved for symptomatic patients only. Minimally invasive surgery (MIS) for treatment of esophageal diverticula encompasses rigid and flexible intraluminal endoscopy, thoracoscopy and laparoscopy. We here give an overview on the pathogenesis of esophageal diverticula, the minimally invasive surgical techniques for treatment and the recent literature. Additionally, we present our own experience with MIS for midthoracic diverticula.Methods
We analyzed the cases of patients who underwent MIS for midthoracic diverticula with regard to preoperative symptoms, perioperative and follow-up data.Results
Three patients (two female, one male, age 79, 78 and 59 years) received thoracoscopic surgery for midthoracic diverticula. All patients reported of dysphagia and regurgitation. In two patients pH-investigation showed pathological reflux but manometry was normal in all patients. Operating time was 205, 135 and 141 minutes. We performed intraoperative intraluminal endoscopy in all patients. There were no intraoperative complications and although no surgical complications occured postoperatively one patient developed pneumonia which advanced to sepsis and lethal multi organ failure. Upon follow-up the two patients did not have recurrent diverticula or a recurrence of previous symptoms.Conclusions
Surgery for diverticular disease of the esophagus has been associated with high rates of morbidity and mortality. Despite the lethal non-surgical complication we encountered, with regard to recent publications minimally invasive apporaches to treat patients with symptomatic esophageal diverticula entail lower rates of complications with better long term results in comparison to open surgery. 相似文献148.
149.
150.
There has been an increasing amount of work worldwide in search for tests not only to be able to absolutely diagnose acute pancreatitis, but more importantly to prognosticate patients at admission. While the tests are still within the realm of research laboratories and involve complex computing and analytical methods, we believed that the already widely practiced methods of scoring needed to be verified in the Indian context. And, hence, the study. 相似文献