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A Ascari-Raccagni†‡ MG Righini† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):514-516
BACKGROUND: Repairing dorsal nasal defects is a frequent challenge for dermatologic surgeons, mainly due to the high frequency of basal cell carcinomas on this site. Obvious scars, mismatched skin and distortion of the nasal contour are the surgical hazards that must be avoided in these cases. AIM: Our aim was to perform surgery involving a simple flap in order to repair medium to large defects on the dorsal side of the nose. METHODS: The dorsal horizontal advancement flap was studied in 12 patients, in order to evaluate the benefits and limits of this surgical procedure. RESULTS: The resulting scars on most of our patients were well-camouflaged among their natural skin lines, and there was neither distortion of the alar contour nor the nostril. CONCLUSIONS: This flap is easy to perform and, in selected cases, provides an outstanding alternative to second-intention healing, full-thickness skin grafts, transposition, rotation and pedicle flaps. 相似文献
3.
A method for the accurate determination of anti-hapten cytotoxic T lymphocyte precursors: correction for apparent 'anti-self' reactivity 总被引:1,自引:0,他引:1
A method is described for accurately determining the frequency of precursors of hapten specific cytotoxic T cells. The method is based on a standard Poisson analysis of limit dilution cultures, but makes a correction of 'anti-self' reacting clones and for spontaneously arising clones that recognise modified self. These corrections are shown to be especially important when low hapten densities are used, where there may be more than a 10-fold difference between the corrected and uncorrected frequency estimates. Determined levels of antigen specificity and of H-2 restriction are significantly enhanced by application of this method. 相似文献
4.
Piccolino M Vellani V Rakotobe LA Pignatelli A Barnes S McNaughton P 《The European journal of neuroscience》1999,11(11):4134-4138
At the first synaptic level of the vertebrate retina, photoreceptor light responses are transmitted to second order neurones through a chemical synapse based on a tonic release of neurotransmitter modulated by graded changes of presynaptic potential. The possibility that such synapses could work through a Ca2+-independent process had been proposed by previous authors, based on the persistence of transmission process in low Ca2+ media containing Co2+ or Ni2+ ions. Recently, we were able to explain these results within the framework of the classical calcium-hypothesis of synaptic transmission by taking into account the modifications of presynaptic surface potential brought about by changes of divalent cation concentrations. Here we report data showing how a surface-charge hypothesis could account for several apparently paradoxical effects of divalent cation manipulations such as: the enhancement of neurotransmitter release induced by low Ca2+ media; the transmission "unblocking" effect of Zn2+, Co2+ and Ni2+; and the reversal of transmission polarity induced by application of low Ca2+ media containing Cd2+ or Mg2+ ions. 相似文献
5.
D. A. Chaukar S. G. Prabhudesai N. L. Bhambhani K. A. Pathak V. D. Sanghvi 《Indian journal of otolaryngology and head and neck surgery》2006,58(1):92-94
Most thyroid cancers (90–95%) are well differentiated. Well differentiated cancers of the thyroid are usually confined to
the thyroid capsule, making them amenable to isolated thyroid resection. Invasion of the upper aerodigestive tract by these
cancers is infrequent and hypopharyngeal invasion is still rare. We report a 51 year old man with thyroid cancer invading
the hypopharynx, who was successfully managed with complete resection along with a partial pharyngectomy. He is asymptomatic
and disease free eighteen months after surgery. We advocate aggressive surgical extirpation of thyroid carcinoma invading
the upper aerodigestive tract. 相似文献
6.
In recent years, numerous atypical Bluetongue virus (BTV) strains have been discovered all around the world. Atypical BTV strains are phylogenetically distinct from the classical BTV serotypes 1–24 and differ in terms of several biological features. For the first time, the atypical strains BTV-25-GER2018 and BTV-33-MNG3/2016 as well as the re-emerged classical strain BTV-8-GER2018 were evaluated comparatively in a pathogenesis study in goats—the natural host of atypical BTV. A substantial number of in-contact animals were included in this study to detect potential contact transmissions of the virus. After infection, EDTA blood, ocular, nasal and oral swab samples as well as serum were collected regularly and were used for virological and serological analyses, respectively. Our study showed differences in the immunological reaction between the two atypical BTV strains (no group-specific antibody detection) and the classical BTV strain BTV-8-GER2018 (group-specific antibody detection). Furthermore, we observed an increase in the total WBC count (neutrophils and lymphocytes) in goats infected with the atypical BTV strains. No horizontal transmission was seen for all three strains. Our study suggests that the atypical BTVs used in the trial differ from classical BTVs in their immunopathogenesis. However, no evidence of direct contact transmission was found. 相似文献
7.
Botulinum neurotoxin injection surrounding the nose area is frequently used in aesthetic settings. However, there is a shortage of thorough anatomical understanding that makes it difficult to treat wrinkles in the nose area. In this study, the anatomical aspects concerning the injection of botulinum neurotoxin into the nasalis, procerus, and levator labii superioris alaeque muscles are assessed. In addition, the present knowledge on localizing the botulinum neurotoxin injection point from a newer anatomy study is assessed. It was observed that, for the line-associated muscles in the nose region, the injection point may be more precisely defined. The optimal injection sites are the nasalis, procerus, and levator labii superioris alaeque muscles, and the injection technique is advised. We advise the best possible injection sites in association with anatomical standards for commonly injected muscles to increase efficiency in the nose region by removing the wrinkles. Similarly, these suggestions support a more precise procedure. 相似文献
8.
PurposeOptical retina images are scaled based on eye size, which results in a linear scale ratio of 10:1 for human versus mouse and 7:1 for macaque monkey versus mouse. We examined how this scale difference correlates with the structural configuration of synaptic wiring in the rod spherule (RS) between macaque and mouse retinas compared with human data.MethodsRod bipolar cell (BC) dendrites and horizontal cell (HC) axonal processes, which invaginate the RS to form synaptic ribbon-associated triads, were examined by serial section transmission electron microscopy.ResultsThe number of rod BC invaginating dendrites ranged 1∼4 in the macaque RS but only 1∼2 in the mouse. Approximately 40% of those dendrites bifurcated into two central elements in the macaque, but 3% of those dendrites did in the mouse. Both factors gave rise to 10 invagination patterns of BC and HC neurites in the macaque RS but only two in the mouse. Five morphological parameters: the lengths of arciform densities and ribbons, the area of the BC–RS contact, and the surface areas of BC and HC invaginating neurites, were all independent of the invagination patterns in the macaque RS. However, those parameters were significantly greater in the macaque than in the mouse by ratios of 1.5∼1.8.ConclusionsThe primate RS provides a more expansive BC–RS interface associated with the longer arciform density and more branched invaginating neurites of BCs and HCs than the mouse RS. The resulting greater synaptic contact area may contribute to more efficient signal transfer. 相似文献
9.
Antioxidant properties of ursodeoxycholic acid 总被引:5,自引:0,他引:5
Lapenna D Ciofani G Festi D Neri M Pierdomenico SD Giamberardino MA Cuccurullo F 《Biochemical pharmacology》2002,64(11):1661-1667
We have investigated potential antioxidant properties of the clinically relevant bile acid UDCA, which reaches therapeutic concentrations up to 0.09 and 29 mM, respectively, in human plasma and bile. UDCA was an excellent scavenger of OHz.rad; generated by FeCl(3)-EDTA, H(2)O(2) and ascorbate in the deoxyribose oxidation test, showing IC(min) and IC(50) values of 0.02 and 0.2 mM, respectively, and a second-order rate constant for reaction with OHz.rad; of 2+/-0.1 x 10(10)M(-1)s(-1). Notably, the drug could enhance at 1.5 mM concentration the antioxidant capacity of human bile against OHz.rad;-induced deoxyribose oxidation. UDCA also showed antioxidant effects in the deoxyribose test performed with nonchelated iron ions, such as Fe(2+) plus H(2)O(2) (IC(min): 7 mM, IC(50): 20 mM) or Fe(3+) plus H(2)O(2) and ascorbate (IC(min): 0.3 mM, IC(50): 5 mM), and inhibited ferrozine-Fe(2+) and desferrioxamine-Fe(3+) complexes formation with IC(50) values of, respectively, 12 and 0.3 mM, indicating that the drug interacts more with iron(III) than with iron(II). Moreover, UDCA significantly inhibited phospholipid liposome peroxidation induced by the OHz.rad;-generating system FeCl(3)-EDTA, H(2)O(2) and ascorbate (IC(min): 0.75 mM, IC(50): 3 mM), and by peroxyl radicals generated in the aqueous phase by AAPH (IC(min): 8 mM, IC(50): 14 mM). UDCA, even at 25 mM concentration, was ineffective on the lipoperoxidation mediated by Fe(2+) alone, but at the same concentration counteracted significantly that by Fe(3+) plus ascorbate, further pointing to its preferential antioxidant interaction with iron(III).In conclusion, UDCA has direct antioxidant properties, which are especially relevant against Fe(3+)- and OHz.rad;-dependent biomolecular oxidative damage; such properties are evident at therapeutically relevant drug concentrations, suggesting that UDCA could act as an antioxidant in vivo. 相似文献
10.
目的:应用IOL-Master测量大学生近视眼的眼轴长度(AL),水平、垂直角膜屈光力(K1,K2),前房深度(ACD)及角膜直径,探讨大学生近视眼各屈光成分值与屈光度的关系以及大学生近视眼的主要成因。方法:大学生近视患者1059例2118眼,经电脑验光按等效屈光度分为三组:A组低度近视<-3.00D(738眼),B组中度近视-3.00~-6.00D(989眼),C组高度近视>-6.00D(391眼)。采用光学相干生物测量仪(Zeiss,IOL-Master)测量其AL,K1,K2,ACD及角膜直径,计算眼轴长度与角膜曲率的比值AL/CR,数据采用SPSS18.0统计分析。结果:随着近视屈光度的增加,眼轴长度明显增加,两者之间存在显著相关性(P<0.01),且各组间具有显著差异性(P<0.01);K1在A组与B组间差异无显著性(P>0.05),K2在各组间具有差异性(P<0.05),但K1和K2仅与中度近视的屈光度存在相关性(P<0.05);各组AL与K1、K2呈负相关,且有显著统计学意义(P<0.01);ACD在B组与C组间差异无显著性(P>0.05),低度近视的屈光度与ACD存在显著相关性(P<0.01);角膜直径在各组间无显著性差异(P>0.05),且与屈光度无相关性(P>0.05);AL/CR比值3.183±0.132,近视屈光度与AL/CR比值呈负相关(r=-0.761,P=0.000)。结论:轴性近视是大学生近视的主要类型。大学生中度近视是眼轴与角膜屈光力共同作用所致;ACD对大学生近视屈光度影响较小;角膜直径对大学生近视屈光度无影响。 相似文献