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排序方式: 共有727条查询结果,搜索用时 15 毫秒
1.
Yana Suchy David S Kosson 《Journal of the International Neuropsychological Society》2006,12(4):538-548
Three hypotheses for cognitive deficits among psychopaths were tested: executive dysfunction, left hemisphere activation, and an interaction between the two. Twenty-one psychopathic and 23 nonpsychopathic criminal offenders identified with the Hare Psychopathy Checklist-Revised participated in verbal and visual-spatial tasks during which the level of executive processing demands was manipulated. Consistent with prior research, psychopathic offenders made more errors than controls, but only during the verbal task and only on trials with high executive demand. Within those trials, most errors occurred when set-maintenance demands were the highest. No response latency differences between groups were found. 相似文献
2.
V Vilgrain J Frija C Yana L J Couderc M David J P Clauvel M Laval-Jeantet 《Journal de radiologie》1989,70(3):167-173
Three patients with lymphoid interstitial pneumonia (two HIV 1+ patients with chronic lymphadenopathic syndromes and one with a not-characterized autoimmune disease) have been studied with high-resolution computed tomography (HR-CT). This technique reveals septal lines, small reticulonodular opacities, polyhedral micronodular opacities, "ground-glass" opacities and a dense, subpleural, curved broken line in one patient. The lesions dominate in the bases of the lungs. They are not characteristic for lymphoid interstitial pneumonia. If a patient present with a chronic lymphadenopathic syndrome, the diagnosis of an opportunistic infection should not be automatically made, since the syndrome can be caused by lymphoid interstitial pneumonia. 相似文献
3.
将昆明小鼠随机分为低(0.025)、中(0.05)、高(0.1)剂量组及生理盐水对照组,以2号海洛因经腹腔注射染毒,20天后,取睾丸组织制成石蜡切片.HE染色,光镜下观察生精小管上皮细胞的形态变化,并应用图像分析系统对初级精母细胞的形态参数进行了分析;结果表明,(1)光镜观察 对照组及低剂量组小鼠睾丸组织未见明显的变化;中剂量组小鼠睾丸曲细精管上皮有不同程度的组织改变;高剂量组小鼠生精管壁细胞明显地出现上皮层次减少,精子细胞和精子减少,并发现曲细精管内有脱落的生精细胞;(2)形态定量分析显示 低剂量组及中剂量组各形态参数(中剂量组圆形度除外)较对照组无显著差异;高剂量组初级精母细胞核面积、核灰度与对照组相比无显著差异,细胞面积、细胞周长及浆面积较对照组明显增大(P<0.05).而核浆比例、圆形度较对照组有减小(P<0.05).结果提示 海洛因可明显改变小鼠生殖细胞的形态结构. 相似文献
4.
Aneta Yoneva Katia Georgieva Yana Mizinska Boyko B. Georgiev Stoyanka R. Stoitsova 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2006,51(3):200-208
The ultrastructure of the mature spermatozoon and the spermiogenesis of a cestode belonging to the family Metadilepididae
is described for the first time. The mature spermatozoon of Skrjabinoporus merops is characterized by twisted peripheral microtubules, the presence of a single crested body, periaxonemal sheath and electron-dense
rods, and the absence of intracytoplasmic walls and inclusions (glycogen or proteinaceous granules); no peripheral microtubules
where nucleus contacts the external plasma membrane. Four morphologically distinct regions of the mature spermatozoon are
differentiated. The proximal part (Region I) contains a single crested body, periaxonemal sheath is absent in some (proximal)
sections and is present in others situated closer to the nucleus. The central Region II is nucleated, and is followed by Region
III that contains a periaxonemal sheath. The distal pole, Region IV, is characterized by disintegration of the axoneme. Spermiogenesis
follows the type III pattern (Ba and Marchand 1995) although in S. merops a slight flagellar rotation is observed. The differentiation zone is characterized by the absence of striated roots and intercentriolar
body; two centrioles are present, one of which gives rise to a free flagellum. The latter rotates and undergoes proximodistal
fusion with the cytoplasmic protrusion of the differentiation zone. Spermiological characters of S. merops are similar to those of the families Taeniidae and Catenotaeniidae. The mature spermatozoon differs from those of the Dilepididae
(where the metadilepidid species have previously been classified) by the lack of glycogen. 相似文献
5.
Anfinogenova YJ Baskakov MB Kovalev IV Kilin AA Dulin NO Orlov SN 《Pflügers Archiv : European journal of physiology》2004,449(1):42-55
This study elucidates the role of cell volume in contractions of endothelium-denuded vascular smooth muscle rings (VSMR) from the rat aorta. We observed that hyposmotic swelling as well as hyper- and isosmotic shrinkage led to VSMR contractions. Swelling-induced contractions were accompanied by activation of Ca2+ influx and were abolished by nifedipine and verapamil. In contrast, contractions of shrunken cells were insensitive to the presence of L-type channel inhibitors and occurred in the absence of Ca2+o. Thirty minutes preincubation with bumetanide, a potent Na+,K+,Cl– cotransport (NKCC) inhibitor, decreased Cl–i content, nifedipine-sensitive 45Ca uptake and contractions triggered by modest depolarization ([K+]o=36 mM). Elevation of [K+]o to 66 mM completely abolished the effect of bumetanide on these parameters. Bumetanide almost completely abrogated phenylephrine-induced contraction, partially suppressed contractions triggered by hyperosmotic shrinkage, but potentiated contractions of isosmotically shrunken VSMR. Our results suggest that bumetanide suppresses contraction of modestly depolarized cells via NKCC inhibition and Cl–i-mediated membrane hyperpolarization, whereas augmented contraction of isosmotically shrunken VSMR by bumetanide is a consequence of suppression of NKCC-mediated regulatory volume increase. The mechanism of bumetanide inhibition of contraction of phenylephrine-treated and hyperosmotically shrunken VSMR should be examined further. 相似文献
6.
Noriyuki Masuda Shunichi Negoro Kouji Takeda Nobuhide Takifuji Tomonori Hirashima Takashi Yana Noriaki Kurata Takashi Kuwabara Satoshi Kobayashi Shinzoh Kudoh Kaoru Matsui Minoru Takada Masahiro Fukuoka 《Investigational new drugs》1999,16(3):245-254
(E)-2-deoxy-2-(fluoromethylene)cytidine (FMdC), one of the most potent inhibitors of ribonucleoside diphosphate reductase, was selected for clinical development because of its novel mechanisms of action, and strong antitumor activity against experimental tumor models. This study was designed to determine the toxicities, maximum-tolerated dose (MTD), and pharmacokinetic profile of FMdC. FMdC was given orally for 5 consecutive days every 3 or 4 weeks in patients with advanced solid tumors. The starting dose was 8 mg/m2/day. Pharmacokinetic studies were carried out on days 1 through 5 of the first cycle. Ten patients with non-small cell lung cancer received 15 courses of FMdC at doses which were de-escalated from 8 mg/m2/day to 2 mg/m2/day because of unexpected severe toxicities at the starting dose level. Neutropenia was the dose-limiting toxicity. Thrombocytopenia and anemia were mild. Flu-like symptoms and fever were the common non-hematologic toxicities. The MTD was 4 mg/m2/day, since four of six patients developed grade 3–4 neutropenia. At the 4 mg/m2/day dose level, the mean terminal half-life, maximum plasma concentration (Cmax), plasma clearance, and mean residence time on day 1 were 3.20 h, 15.8 ng/ml, 2.91 l/h/kg, and 4.03 h, respectively. The recommended dose for phase II studies with this schedule is also 4 mg/m2/day for 5 days. Further investigations are necessary to establish optimal dosing schedules and routes for the administration of FMdC. 相似文献
7.
8.
Anthocyanins have poor bioavailability, but the factors affecting this remain unclear. Uptake into cells could impact the bioavailability; therefore, understanding factors affecting anthocyanin uptake is pivotal to improve their bioavailability and reveal the mechanism for their uptake. This study aimed to investigate the effect of anthocyanin structure, pH and glucose on the uptake of anthocyanins by Caco-2 cells. Anthocyanin extract from strawberry and red grape at 10 or 20 µM was added to Caco-2 cells. Anthocyanin toxicity to the cells was firstly examined to ensure the same cell viability. The uptake was carried out at pH 7 and 6.5 to evaluate the effect of pH. Glucose (1 mM) was used to investigate its effect. The results show that anthocyanins toxicity was dependent on the concentration and length of exposure. Anthocyanin uptake was concentration-dependent and affected by their structures, in which cyanidin-3-glucoside uptake was higher than pelargonidin-3-glucoside. No metabolites from Caco-2 cell activity were detected. An increased uptake with a decrease in pH was observed, which may be linked to the increase in anthocyanins stability and may indicate the role of proton co-transporter. This also suggests that the jejunum would be the favourable section of small intestine for anthocyanin uptake. Reduced anthocyanin uptake in the presence of glucose suggested that facilitative glucose transporter could be involved in the uptake of anthocyanins by Caco-2 cells. 相似文献
9.
部分背根切断及针刺对备用背根节神经元血小板源性生长因子表达的影响 总被引:1,自引:1,他引:0
目的:探讨部分去背根及部分去背根后针刺对备用背根节神经元血小板源性生长因子(PDGF)表达的影响。方法:制备猫双侧备用背根节模型,并针刺位于右侧备用根支配区的两组穴位,针刺7d及14d后分别取针刺、非针刺侧备用背根节,行免疫组织化学ABC法显色。分别计数各组阳性神经元总数以及大、中小阳性神经元的数量。结果:PDGF在备用背根节的大、中小神经元均有表达。部分背根切断后,针刺侧、非针刺侧PDGF阳性神经元总数及中小阳性神经元数在7d时较正常显著减少,针刺后7d时,PDGF阳性总数及大神经元数针刺多于非针刺侧,针刺14d时,阳性总数及中小神经元数多于非针刺侧。结论:部分背根切断及针刺可影响PDGF在备用背根节的表达,这种作用显效的时间因不同时相、不同类型的背根节神经元而异。 相似文献
10.
BackgroundLINC00941 has been proved to be related to various tumors, but its relationship with laryngocarcinoma remains vague.MethodsLINC00941 expression in laryngocarcinoma tumor and laryngocarcinoma cells was determined by real time‐quantitative polymerase chain reaction (RT‐qPCR). Besides, the five‐year survival of laryngocarcinoma patients with different LINC00941 expression was analyzed with Kaplan–Meier survival analysis, and the clinical characteristics of laryngocarcinoma patients were also recorded. After transfection, cell viability, cell proliferation, apoptosis, cell cycle, migration, and invasion were detected by cell counting kit‐8 (CCK‐8), colony formation, flow cytometry, cell scratch, and Transwell assays, respectively. Glycolysis was assessed by the colorimetric method. Expressions of proliferation‐associated proteins, migration‐associated proteins, glycolysis‐associated proteins, and phosphatidylinositol 3‐kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signal pathway‐associated proteins were detected by Western blot.ResultsIn laryngocarcinoma tumor tissues and cells, LINC00941 was highly expressed. High expression of LINC00941 decreased the 5‐year survival of laryngocarcinoma patients, and it was positively related to lymph node metastasis and clinical stages. LINC00941 overexpression decreased apoptosis but promoted cell viability, proliferation, cell‐cycle progression, migration, and invasion, and glucose consumption and lactate production in laryngocarcinoma cells. Moreover, LINC00941 overexpression elevated expressions of Ki‐67, PCNA, MMP2, N‐Cadherin, HK2, PFKFB4, and PKM, activated the PI3K/AKT/mTOR signal pathway but reduced E‐Cadherin expression, while LINC00941 silencing had the opposite effects. PKM overexpression reversed the effects of LINC00941 silencing on cellular and glycolytic phenotypes.ConclusionLINC00941 promoted in vitro progression and glycolysis of laryngocarcinoma cells by upregulating PKM via activating the PI3K/AKT/mTOR signaling pathway. 相似文献