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101.
102.
Effect on peripheral nerve vivo with human insulin-like regeneration by transgene in growth factor-1
BACKGROUND: Human insulin-like growth factor (hIGF-1) has been successful in treating peripheral nerve injury, but it is still unclear whether hIGF-1 after transgene in vivo has the effect on promoting the regeneration of peripheral nerve.
OBJECTIVE: To observe the effect of hIGF-1 on the regeneration of peripheral nerve by transgene in vivo with electrophysiology, histological morphology and ultromicro morphology.
DESIGN: A univariate design.
SETTINGS: Jilin Institute of Surgery, China-Japan Friendship Hospital Affiliated to Jilin University; School of Basic Medical Sciences, Jilin University.
MATERIALS: Thirty male adult Wistar rats of grade Ⅱ, weighing 200-250 g, were provided by the Animal Experimental Center of Jilin University [certification number: SCXK-(Ji)20030001]. The rats were raised in the environment at the temperature of 25 ℃ and humidity of 70%. All the rats were randomly divided into hIGF-1-treated group, treatment control group and blank control group, 10 rats in each group. Positive liposomes (mass concentration of 2 g/L) and pcDNA3.1 (mass concentration of 1 g/L) were purchased from Beijing Yuanpinghao Company; pcDNAhIGF-1 (mass concentration of 1 g/L) was provided by Dr. Shen from the School of Public Health of Jilin University. The liposomes were mixed with plasmids with the mass ratio of 1.5 to 10.Operative microscope was made by Jiangsu Zhenjiang Microsurgical Instrument Factory; EMB-5304K electromyogram (EMG) evoked potential meter by Nihon Kohden Corporation. HPIAS-1 000 high-acuity color pathological imaging analytical system (Japan) and JEM-1200EX transmission electron microscope (Japan) were also used.
METHODS: The experiments were carried out in Jilin Institute of Surgery from April to June in 2004. ① All the rats were anesthetized, and the right sciatic nerve was exposed, and it was clipped with a clip at 5 mm below the piriform muscle for 3 times, 10 s for each time. The pressed width was 3 mm, and formed as membrane under operating microscope (×6). Rats in the hIGF-1-treated group were subepineurially injected with the mixture of pcDNAhIGF-1 and positive liposomes (10 μL) immediately, those in the treatment control group were injected with the mixture of pcDNA3.1, positive liposomes and distilled water (10 μL), and those in the blank control group were not given any injection. ② The sciatic nerve functional indexes (SFI) were measured within 56 days postoperatively according to the methods used by Shen et al. ISFI=0 was taken as normal, and ISFI=-100 as completely damaged. EMG evoked potential meter was used to record the electrophysiological changes of the regenerated nerve fibers. The indexes of histological morphology in 5 randomly selected sights were determined with the color pathological imaging analytical system, and the ultrostructures of the regenerated nerve fibers were also observed.
MAIN OUTCOME MEASURES: ① Comparison of the SFI within 56 days postoperatively; ② Comparison of the electrophysiology, histological morphology and ultrastructure of the regenerated nerve fibers 56 days postoperatively.
RESULTS: All the 30 Wistar rats were involved in the analysis of results. ① SFI: The SFI values were gradually increased as time prolonged in all the three groups, and the changes were more obvious after 24 days, the SFI values recovered better at each time point in the hIGF-1-treated group than in the other two groups. ② Eelectrophysiological results of right sciatic nerve: The latency of motor evoked potential (MEP) was close between the treatment control group and the blank control group [(2.55±0.36), (2.65±0.55) ms, P > 0.05], but higher in the hIGF-1-treated group [(2.14±0.22) ms] than in the blank control group (P < 0.01). The amplitude and conduction velocity of MEP in the treatment control group [(6.67±0.69) mV, (29.57±4.06) m/s] were close to those in the blank control group [(6.60±0.59) mV, (29.22±3.20) m/s, P > 0.05], but those in the hIGF-1-treated group [(7.81±0.84) mV, (36.91±4.37) m/s] were larger or faster than those in the blank control group (P < 0.01). ③ Results of the pathological image analysis of the regenerated nerve fibers: The axonal diameter, thickness of myelin sheath of the regenerated nerve fiber and the number of myelinated nerve fiber in the treatment control group [(2.28±0.33) μm, (1.08±0.18) μm2, (71.80±8.25) fibers] were close to those in the blank control group [(2.18±0.29) μm, (1.03±0.15) μm2, (68.60±8.55) fibers] (P > 0.05), and those in the hIGF-1-treated group [(3.03±0.35) μm, (1.65±0.24) μm2, (88.20±8.82) fibers] were obviously larger or more than those in the blank control group (P < 0.01). ④ Ultrastructure of the regenerated nerve fibers of sciatic nerve: In the hIGF-1-treated group, the regenerated fibers of sciatic nerve were more and mature, manifested by thicker nerve fibers, thicker and evener myelin sheath, which were better than those in the other two groups.
CONCLUSION: The results of the quantitative parameters of the electrophysiology, gross histological morphology and ultrostructural changes in the process of repairing damaged peripheral nerve indicate that transgene in vivo with hIGF-1 can promote the neural regeneration after peripheral nerve injury. 相似文献
103.
Until now methods using tetramethylbenzidine (TMB) for electron microscopy (TMB-EM methods) are all unable to provide a maximum demonstration of transported horseradish peroxidase (HRP) while maintaining good ultrastructural tissue preservation. In order to solve this problem, we have attempted to adapt a newly developed, highly sensitive TMB method using sodium tungstate (ST) as the stabilizer (TMB-ST method) for HRP electron microscopic retrograde and anterograde fiber tracing. The present study shows that the TMB-ST method combined with diaminobenzidine-cobalt (DAB-Co) is more sensitive than existing TMB-EM methods and that ultrastructural details are well preserved with this combined method. The resultant reaction product complex after osmication is stable and is observed as characteristic crystal-like structures which are extremely electron dense and often aggregated into clumps. In contrast, the TMB-ST method without the DAB-Co step frequently produces a moderate electron-dense reaction product. Therefore, we recommend the TMB-ST method combined with DAB-Co for HRP electron microscopy. 相似文献
104.
105.
A case of adrenal hemangioma is reported, displayed by computed tomography and confirmed by pathologic investigation. This rare tumor poses a difficult diagnostic challenge and rejoins the problem of incidentally discovered adrenal masses. 相似文献
106.
从蝮蛇毒中提取磷酸二酯酶,用此酶免疫BALB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞Fo融合,以间接ELISA检测杂交瘤细胞培养上清液和小鼠腹水中的特异性抗体,其效价分别为1∶128和1∶51 200.抗原阻断试验结果表明,此抗体对蛇毒磷酸二酯酶具有特异性.该杂交瘤细胞株定为G_8,该株单抗属鼠IgG_(2a)亚型,经体外持续培养6个月,其分泌抗体性能稳定. 相似文献
107.
X Sala-Barangé R Vilana C Ribas M Marquez X Iglesias Gu?u 《Journal de radiologie》1988,69(8-9):539-541
The authors explain the clinical case of a female patient suffering from secondary sterility; she was submitted, among other test, to the H.S.G. in order to study the possibility of a among other tests, to the H.S.G. in order to study the possibility of a cervical failure. The radiological findings obtained of Morgagni's Hydatis, not described previously in literature and their laparoscopic confirmation justify, we believe, its publication. 相似文献
108.
给大鼠应用环孢素(CsA)50mg/kg·d灌胃,共10天,引起高血糖症及血浆和胰腺组织中胰岛素水平下降。同时联合应用川芎嗪(LIG)50mg/kg·d共10天,能有效地防止和(或)减轻CsA引起的上述变化。LIG还有效地减轻了CsA引起的尿血栓素B_2和尿血栓素B_2/6-酮-前列腺素F_(1α)值的升高。结果提示LIG对CsA引起的胰岛β细胞毒性的防护作用可能与调节前列胰素代谢有关。 相似文献
109.
报道我院1958~1992年期间的 Ebstein 畸形82例。平片表现可归纳为球型、方型和不典型4种心脏形态。介绍该畸形的心血管造影方法,所见征象和相应的病理基础。主要造影征象有:1.心脏膈面双切迹征;2.帆样征:3.房化心室:4.三尖瓣闭锁不全。本文结合文献对本病病理,X 线表现进行了系统的讨论,并着重突出了我们的观点。 相似文献
110.
The localization of tachykinin-immunoreactivity in the cat visual cortex (area 17) was investigated using immunohistochemical methods. Strong laminar specificity was observed, with immunoreactivity highest in layer V, followed by layers I, VI, II and III, and the lowest density in layer IV. Most of the immunoreactive product was localized in neuronal processes. A few immunopositive cell bodies were also present. The immunopositive neurons were non-pyramidal, multipolar, or bipolar in shape, and mostly found in layer V. There were particularly dense immunopositive fibers and varicosities around somata in layer V. These may represent tachykinin-containing presynaptic terminals (boutons). The results provide anatomical evidence that tachykinin may primarily affect layer V neurons in the cat visual cortex. 相似文献