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41.
L. Bon C. Lucchetti 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,102(2):259-271
We evoked both ear and eye movements in area 8b, the rostral area of frontal cortex, in two monkeys. In some sites it was possible to evoke only ear movements or only eye movements; in other locations we evoked both ear and eye movements by varying the intensity of electrical stimulation. The electrically evoked ear movements were forward, or backward, or oblique (upward-forward; upward-backward). In two penetrations the ear movements were bilateral, in the other penetrations they were contralateral. Ipsilateral ear movements were not observed. The evoked eye movements were mainly fixed-vector saccades, contralateral and with an upward orientation of about 45°. If we considered only the sites where the threshold was equal to or lower than 50 A, the stimulation of this area evoked mainly ear movements. In addition we recorded the electrical activity of 195 neurons. Of these neurons: 74% (145/195) discharged before ear movements (ear cells); 20% (40/195) discharged before ear and eye movements (ear-eye cells); 5% (10/195) discharged only before eye movements (eye cells). Ninety-one percent (132/145) of ear cells presented a preferred direction; 90% (36/40) of ear-eye cells presented a preferred direction for ear movements, and 15% (6/40) presented a preferred direction for eye movements. Eighty-five percent (34/40) of cells did not present a preferred direction for visually guided saccades and were active when the monkey made saccades toward the unlit targets (checking saccades). Our results show that a field of area 8b is related to ear movements and to eye-ear movements. The findings that it is possible to obtain both ear and eye movements with low-intensity currents and that there are cells firing for the two types of movements suggest that area 8b may be involved in the orientation and coordination of both ear and eye. This area might be considered a rostral extension of supplementary eye field (SEF) or a different region. However, based on its distinct functional characteristics and connectivity, it is probably better regarded as a separate field. Regardless, the combination of 8b and SEF may constitute a cortical center for orienting processes. 相似文献
42.
目前临床检验中的固相化学法主要是多层膜法(Multiple Layer-Film),它集当代化学、光学、酶学、化学计量和计算机技术于一体,并已作为定量分析法达到常规湿化学法的测定水平。由于其具有准确度高、精密度高;标本量少;不需配制试剂操作简便、快速,可随时随地进行.无废液产生等优点,更适用于实验动物特别是小动物的体内生化成份测定。本项研究目的在于应用囿相化学法的优点以新西兰大耳兔为实验动物模型对兔血清中的ALT、AST、GLU、TB、BUN和Ca^2 进行分析测定,并应用临床化学分析法的选择和评价原理,在重复性实验、稀释实验、回收实验和方法比较实验等方面进行丁固相化学法对实验动物血清中生化成分测定的可行性实验探讨。 相似文献
43.
Bánkfalvi Á Piffkó J Öfner D Dreier R Böcker W Werner K 《Pathology oncology research : POR》1996,2(1-2):71-77
Until recently the only way to rescue masked epitopes in routinely processed surgical pathological material was enzymatic
digestion. The use of heat for antigen retrieval, first by microwave irradiation, represents an important breakthrough in
immunohistochemistry. With the acceptance of microwave oven pretreatment, various modified techniques and alternative heating
methods have also been proposed. Wet autoclave pretreatment for tissue proteolysis is a highly reliable alternative to the
microwave antigen retrieval technique. It provides uniform heating of the slides, hence an even enhancement of staining intensity
in a variety of formalin-sensitive antigens, and it also offers consistent interlaboratory results. The method has been introduced
in routine diagnostic immunohistochemistry for the detection of estrogen-and progesterone receptors, L26-, Ki-67- and bcl-2
antigens and variable types of cytokeratins (1/5/10/11, 8, 13, 19). Experimentally, wet autoclaving can be used very successfully
for the immunophenotyping of p53 and mdm2 expression, for the detection of adhesion molecules (CD44, integrins) and some anti-inflammatory
molecules (annexins), among others. It has produced a substantial improvement in the visualisation of silver-stained nucleolar
organizer regionsassociated proteins (AgNORs) in routine paraffin sections and along with modified silver staining and standardized
AgNOR parameters assessed by image analysis. Wet autoclaving-based AgNOR staining has been proposed by a European multicentric
study group as the standardized method for AgNOR analysis in archival material. 相似文献
44.
Pekka Honkavaara Ilmari Pyykkö Eeva-Marja Rutanen 《Journal canadien d'anesthésie》1996,43(11):1108-1114
Purpose
To assess the effect of the menstrual cycle on post-operative retching and vomiting (R& V) after middle ear surgery, and the efficacy of prophylaxis against R& V in female patients with transdermal scopolamine during either general or local anaesthesia and with intravenous ondansetron during general anaesthesia. 相似文献45.
Jan Abrahamsen Ove A. Nedergaard 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):161-165
Summary The aim of the present investigation was to examine whether or not presynaptic facilitatory -adrenoceptors are detectable on the postganglionic nerves in the rabbit isolated ear artery. Strips of rabbit central ear artery were incubated with 3H-noradrenaline (10–7 mol/l; 30 min or 10–6 mol/l; 60 min). Subsequently, they were washed repeatedly with physiological salt solution. The strips were subjected to electrical-field stimulation (S1–S8) and the resultant 3H-overflow was determined.When the ear artery was stimulated with 150 pulses (0.5 ms; 3 Hz; 225 mA), isoprenaline (10–9–10–6 mol/l) either alone or in the presence of either rauwolscine (10–6 mol/l) or phentolamine (10–6 mol/l) did not alter the stimulation-evoked 3H-overflow. This was also the case in the presence of rauwolscine (10–6 mol/l) plus either the selective phosphodiesterase inhibitor ICI 63 197 (3 × 10–5 mol/l) or forskolin (10–6 mol/l). When the ear artery was stimulated with 300 pulses (1 ms; 5 Hz; 225 mA), isoprenaline had no effect on the stimulation-evoked 3H-overflow. This was also the case when phentolamine (10–6 mol/l) was present. Propranolol (10–7–10–5 mol/l) did not alter the stimulation-evoked 3H-overflow. In some experiments, the stimulation current was reduced to 175 mA in order to obtain similar reference release (S3) values despite the presence of rauwolscine (150 pulses; 0.5 ms; 3 Hz). Even then, isoprenaline (10–9–10–6 mol/l) did not change stimulation-evoked 3H-overflow. The results suggest that postganglionic sympathetic nerves in rabbit central ear artery do not possess presynaptic facilitatory -adrenoceptors.
Send offprint requests to J. Abrahamsen at the above address 相似文献
46.
Otological trauma resulting from the Soho Nail Bomb in London, April 1999 We report the otological effects of the April 1999 Soho Nail Bomb on 17 patients. Twenty‐one (62%) tympanic membranes were perforated (pars tensa only); 78% closed spontaneously within 6 months. The mean size of the perforation in the tympanic membrane nearer to the blast was significantly larger than the opposite side [33% ± 8.3 (mean ± SD) and 13% ± 4.1 respectively; P = 0.02]. All patients reported hearing losses that were mixed conductive and sensorineural but mainly high‐frequency sensorineural (4, 6 and 8 kHz, pure tone average 42.3 dB ± 20.5). The sensorineural hearing loss correlated inversely with the distance from the explosion but not with the size of perforation. There was no significant difference in the hearing loss between the ear facing the blast and the opposite ear. Fifteen patients (88%) had temporary tinnitus. No patient complained of any vestibular symptoms. The otological effects of a nail bomb in an enclosed space have not been previously reported. Furthermore, an inverse correlation between hearing loss and distance from the explosion and a significant difference in perforation size facing the blast, compared with the opposite side, are also presented for the first time. The high spontaneous closure rate of perforations and minimal ongoing disability from sensorineural losses favour conservative management in most cases. 相似文献
47.
48.
49.
Abstract: This report describes an infant with clinical features consistent with the yellow nail syndrome (YNS), a rare autosomal dominant disorder. He presented at birth with congenital lymphoedema and was referred at 6 months of age for investigation of recurrent cough and wheeze. He had clinical and radiological evidence of bilateral pleural effusions and a pericardial effusion. Following a lung biopsy and pericardial window these were shown to be manifestations of his lymphatic abnormality. He also had persisting middle ear effusions causing conductive deafness requiring hearing aids and secondary immunodeficiency requiring regular immunoglobulin infusions. 相似文献
50.
目的:预测盐酸洛美沙星滴耳剂有效期,用以扩大洛美沙星的临床应用,增加耳科用药。方法:采用紫外分光光度法剧定制剂含重.用经典恒温法和Weibull概率法探讨其德定性。结果:紫外分光光度法测定制剂含量平均回收率为99.80% ,RSD为0.66%。经典恒温法预测本制剂在pH为5~6, 25 ℃ 贮存时有效期为5.16年,Weibull概率法预测其有效期为4.98年。结论:紫外分光光度法测定盐酸洛美沙星滴耳剂快速简便,精密度好,可靠性高。在无阳光直射条件下室温贮存本制剂稳定性好。 相似文献