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91.
In this article we review the mechanism of ocular surface staining. Water-soluble dyes are excluded from the normal epithelium by tight junctions, the plasma membranes and the surface glycocalyx. Shed cells can take up dye. A proportion of normal corneas show sparse, scattered time-dependent, punctate fluorescein uptake, which, we hypothesise, is due to a graded loss of the glycocalyx barrier, permitting transcellular entry into pre-shed cells. In pathological staining, there is little evidence of ‘micropooling’ at sites of shedding and the term ‘punctate erosion’ may be a misnomer. It is more likely that the initial event involves transcellular dye entry and, in addition, diffusion across defective tight junctions. Different dye-staining characteristics probably reflect differences in molecular size and other physical properties of each dye, coupled with differences in visibility under the conditions of illumination used. This is most relevant to the rapid epithelial spread of fluorescein from sites of punctate staining, compared to the apparent confinement of dyes to staining cells with dyes such as lissamine green and rose bengal. We assume that fluorescein, with its lower molecular weight, spreads initially by a paracellular route and then by transcellular diffusion. Solution-Induced Corneal Staining (SICS), related to the use of certain contact lens care solutions, may have a different basis, involving the non-pathological uptake of cationic preservatives, such as biguanides, into epithelial membranes and secondary binding of the fluorescein anion. It is transient and may not imply corneal toxicity. Understanding the mechanism of staining is relevant to the standardisation of grading, to monitoring disease and to the conduct of clinical trials. 相似文献
92.
Serving as one of our primary environmental inputs, vision is the most sophisticated sensory system in humans. Here, we present recent findings derived from energetics, genetics and physiology that provide a more advanced understanding of color perception in mammals. Energetics of cis–trans isomerization of 11-cis-retinal accounts for color perception in the narrow region of the electromagnetic spectrum and how human eyes can absorb light in the near infrared (IR) range. Structural homology models of visual pigments reveal complex interactions of the protein moieties with the light sensitive chromophore 11-cis-retinal and that certain color blinding mutations impair secondary structural elements of these G protein-coupled receptors (GPCRs). Finally, we identify unsolved critical aspects of color tuning that require future investigation. 相似文献
93.
Haruno Nishimuro Hirofumi Ohnishi Midori Sato Mayumi Ohnishi-Kameyama Izumi Matsunaga Shigehiro Naito Katsunari Ippoushi Hideaki Oike Tadahiro Nagata Hiroshi Akasaka Shigeyuki Saitoh Kazuaki Shimamoto Masuko Kobori 《Nutrients》2015,7(4):2345-2358
Quercetin is a promising food component, which can prevent lifestyle related diseases. To understand the dietary intake of quercetin in the subjects of a population-based cohort study and in the Japanese population, we first determined the quercetin content in foods available in the market during June and July in or near a town in Hokkaido, Japan. Red leaf lettuce, asparagus, and onions contained high amounts of quercetin derivatives. We then estimated the daily quercetin intake by 570 residents aged 20–92 years old in the town using a food frequency questionnaire (FFQ). The average and median quercetin intakes were 16.2 and 15.5 mg day−1, respectively. The quercetin intakes by men were lower than those by women; the quercetin intakes showed a low correlation with age in both men and women. The estimated quercetin intake was similar during summer and winter. Quercetin was mainly ingested from onions and green tea, both in summer and in winter. Vegetables, such as asparagus, green pepper, tomatoes, and red leaf lettuce, were good sources of quercetin in summer. Our results will help to elucidate the association between quercetin intake and risks of lifestyle-related diseases by further prospective cohort study and establish healthy dietary requirements with the consumption of more physiologically useful components from foods. 相似文献
94.
Antonio Pesce Gaetano Piccolo Francesca Lecchi Nicol Fabbri Michele Diana Carlo Vittorio Feo 《World journal of gastroenterology : WJG》2021,27(36):5989-6003
Laparoscopic cholecystectomy (LC) is one of the most frequently performed gastrointestinal surgeries worldwide. Bile duct injury (BDI) represents the most serious complication of LC, with an incidence of 0.3%-0.7%, resulting in significant perioperative morbidity and mortality, impaired quality of life, and high rates of subsequent medico-legal litigation. In most cases, the primary cause of BDI is the misinterpretation of biliary anatomy, leading to unexpected biliary lesions. Near-infrared fluorescent cholangiography is widely spreading in clinical practice to delineate biliary anatomy during LC in elective and emergency settings. The primary aim of this article was to perform an up-to-date overview of the evolution of this method 12 years after the first clinical application in 2009 and to highlight all advantages and current limitations according to the available scientific evidence. 相似文献
95.
Sympathetic Input to Multiple Cell Types in Mouse and Human Colon Produces Region-Specific Responses
96.
目的 探索制作结构清晰、颜色鲜明、能长期保存的细粒棘球绦虫原头蚴标本的方法。 方法 孔雀绿染色法 :将原头蚴分别用 1%、2 %和 4 %孔雀绿水溶液 ,在室温或 36℃染色 2 4 h、4 8h和 72 h。 结果 4 %孔雀绿水溶液 ,36℃ ,染色 4 8h为最佳条件。染色后原头蚴头钩呈亮绿色 ,而吸盘和实质部分无色透明 ,标本的对比性和立体感强。 结论 用孔雀绿染色法制作原头蚴标本在临床诊断和教学中有实用价值。 相似文献
97.
Balloon-occluded retrograde transvenous obliteration improves liver function in patients with cirrhosis and portal hypertension 总被引:8,自引:0,他引:8
Miyamoto Y Oho K Kumamoto M Toyonaga A Sata M 《Journal of gastroenterology and hepatology》2003,18(8):934-942
BACKGROUND AND AIM: Balloon-occluded retrograde transvenous obliteration (B-RTO) is a novel therapeutic method for the treatment of large gastric fundal varices with spontaneous splenorenal shunt (SRS). However, the effects of B-RTO on liver function remain unknown. METHODS: Fourteen patients with portal hypertension and gastric varices with SRS were studied, consisting of four patients with acute bleeding, five with high-risk varices, and five with refractory portosystemic encephalopathy. Hepatic venous catheterization was performed to evaluate hepatic blood flow and liver function using the continuous indocyanine green (ICG) infusion method. To assess the metabolic activity of the hepatocyte, the intrinsic clearance of ICG was calculated. In all patients, endoscopic study was performed before and 1 week and 1 month after the B-RTO, and followed every 6 months thereafter. After baseline measurements, B-RTO was performed. Four weeks after the B-RTO, the same catheter measurements were repeated. RESULTS: The B-RTO was successful in all patients. Contrast-enhanced computed tomography showed complete obliteration of the SRS prior to the follow-up measurements. Endoscopic eradication of the fundal varices was obtained 6 months after B-RTO in all patients and encephalopathy was improved within 1 week after B-RTO. Following the B-RTO, hepatic blood flow (441 +/- 214 vs 668 +/- 299 mL/min, P < 0.0001) and the intrinsic clearance of ICG (233 +/- 123 vs 285 +/- 148 mL/min, P < 0.05) were significantly increased. Furthermore, intrahepatic resistance decreased after the B-RTO (P < 0.005). CONCLUSION: From short-term assessment, B-RTO increases hepatic blood flow and improves the metabolic activity of the liver in patients with portal hypertension. 相似文献
98.
Nobuko Serizawa Yoshiyuki Takei Hironao Okubo Shunhei Yamasina Nobuyuki Enomoto Nobuhiro Sato 《Hepatology research》2006,34(4):207-213
BACKGROUND/AIMS: Recently liver regeneration by bone marrow transplantation has been proposed as an alternative source of functional liver cells. We investigate commitment of bone marrow cells (BMCs) to liver regeneration and the effect of dalteparin sodium (DS) on regeneration of the damaged liver caused by carbon tetrachloride (CCl(4)) administration in the mice. METHODS: Liver injury was produced in 8-week-old mice by treating with CCl(4) for 4 weeks. Thereafter, mice received a lethal dose of irradiation (10Gy) to whole body, followed by injection of 1x10(7) green fluorescent protein (GFP)-positive BMCs via the tail vein. DS (50IU/kg, intraperitoneally) was administered daily for 28 consecutive days starting at 1 day post-BMC transplantation. Lineage marker analysis of GFP-positive liver cells was performed immunostaining with a CD31 antibody. RESULT: Four weeks after BMC transplantation, GFP-positive cells in the CCl(4)-damaged liver could be detected in the lobule displaying a meshwork architecture extending from the periportal to pericentral regions, a pattern simulating sinusoidal lining. This localization of GFP-positive cells suggested that these cells were closely associated with sinusoidal endothelial cells. By staining the GFP-positive cells for CD31, it was confirmed that the majority of the GFP-positive cells are also positive for CD31. The GFP(+)CD31(+) cells were barely detected in the control group (1.0+/-1.2 per field). In marked contrast, a numerous number of GFP(+)CD31(+) cells were detected in the liver section obtained from the CCl(4)-induced liver damage group (3.8+/-1.3 per field, P<0.05 versus control). The number of GFP(+)CD31(+) cells in CCl(4) plus DS-treated group was further increased to 8.3+/-1.3 per field (P<0.05 versus CCl(4)-induced liver damage group). CONCLUSION: The majority of GFP-positive BMCs was committed to sinusoidal endothelial cells. DS promoted BMC differentiation into sinusoidal endothelial cells in the CCl(4)-damaged liver. 相似文献
99.
BackgroundThis study aimed to investigate the penetration depth of two different dyes after root canal preparation using PIPS and SWEEPS methods.Materials and methodsA total of 60 single-rooted human teeth which were extracted for periodontal reasons were collected and stored in the sterile saline until using in the study. The crowns of the teeth were cut such that the remaining piece was 12 mm long. The root canals were prepared. Teeth were divided randomly into two initial groups (n = 30): indocyanine green solution (ICG) and methylene blue solution. Then, these teeth were divided into final subgroups (n = 10): Er:YAG laser irradiation with PIPS(photon-induced photoacoustic streaming) technique, Er:YAG laser irradiation with SWEEPS(shock-wave enhanced emission photoacoustic streaming) technique, and no irradiation. The penetration depth measurements were done by the stereo microscope in three zones of each specimen.ResultsThe difference between ICG in the control group and PIPS and SWEEPS in the coronal area was not significant. In the middle section the difference between PIPS and the control group was marginally insignificant (P = 0.053). In the methylene blue group, PIPS had significantly higher penetration depth in the apical area compared to the control group (P = 0.004). In the middle section, both PIPS and SWEEPS showed significantly higher penetration than the control group.ConclusionAccording to the results of this study, the laser has the potential to increase the penetration of methylene blue. Root canal preparation with the PIPS technique can increase the dye penetration. However, the SWEEPS technique and the conventional method have a similar outcome in terms of dye penetration. 相似文献
100.
Mihoko Tomida Hidetsugu Tsujigiwa Keisuke Nakano Rina Muraoka Takami Nakamura Norimasa Okafuji Hitoshi Nagatsuka Toshiyuki Kawakami 《International journal of medical sciences》2013,10(10):1321-1326
Background: Bone marrow-derived cells (BMCs) have abilities of cell migration and differentiation into tissues/organs in the body and related with the differentiation of teeth or periodontal tissue including fibroblasts. Then, we examined the effect of orthodontic mechanical stress to the transplanted BMC migration into periodontal tissues using BMC transplantation model.Material and Method: BMC from green fluorescence protein (GFP) transgenic mice were transplanted into 8-week-old female C57BL/6 immunocompromised recipient mice, which had undergone 10 Gy of lethal whole-body-irradiation. Five mice as experimental group were received orthodontic mechanical stress using separator between first molar (M1) and second molar (M2) 1 time per week for 5 weeks and 5 mice as control group were not received mechanical stress. The maxilla with M1 and M2 was removed and was immunohistochemically analyzed using a Dako Envision + Kit-K4006 and a primary anti-GFP-polyclonal rabbit antibody. Immunohistochemically stained was defined as positive area and the pixel number of positive area in the periodontal tissue was compared with the previously calculated total pixel number of the periodontal tissue.Results: The immunohistochemistry revealed that GFP positive cells were detected in the periodontal tissues, both in the experimental and control specimens. The ratio of pixel number in the examination group showed 5.77 ± 3.24 % (mean ± SD); and that in the control group, 0.71±0.45 % (mean ± SD). The examination group was significantly greater than that of control group (Mann-Whitney U test: p<0.001).Conclusion: These results suggest that orthodontic mechanical stress accelerates transplanted BMC migration into periodontal tissues. 相似文献