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51.
Summary Pedicled temporoparietal fascial flaps have been used extensively in head and neck reconstruction for many years. Also, the fascia has been grafted, and the skin graft transformed into a vascularized pedicled flap (prefabricated temporoparietal fasciocutaneous flap). On the other hand, some authors have used free temporoparietal fascial flaps for defects that require to be filled in lower and upper extremity wounds. In this case, a free prefabricated temporoparietal fascio-chondro-cutaneous flap having only an arterial inflow was used in eyelid reconstruction.Presented at the 14th Congress of Turkish Plastic and Reconstructive Surgery, Ankara, Turkey, October 1992  相似文献   
52.
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
53.
BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships.  相似文献   
54.
OBJECTIVE: The purpose of the present study was to determine the distribution and level of temperature, in a model of a maxillary canine, the surrounding periodontal tissues, and the bones, during a System B heat obturation technique simulation. STUDY DESIGN: The temperature distribution was determined by using a three-dimensional finite element analysis. The tooth was assumed to have undergone an endodontic treatment before the application. Heat applications of 200 degrees C and 100 degrees C were considered. RESULTS: By using the virtual model and the simulation technique, the maximum temperature in the periodontal ligament was found to be 43.5 degrees C. CONCLUSIONS: Within the assumptions and the limitations of the study, it was determined that the simulation of System B technique created no potentially harmful levels of temperature throughout the maxillary canine model.  相似文献   
55.
Five-day-old Wistar albino rats were injected with kainic acid (KA) or saline i.p. to investigate time-dependent alterations in morphology and number of basic fibroblast growth factor (bFGF) immunoreactive (-ir) astrocytes and neurons in hippocampus at 15, 30, and 90 days after the injections. Sections were stained with cresyl violet for morphological evaluation and bFGF immunohistochemistry was used for quantitative evaluation of bFGF-ir cell density. Fifteen days after KA injection, there was gliosis but no neuronal loss although disorganization in CA1, CA3, CA4 pyramidal layers and neuronal loss were evident 30 and 90 days after the injection. KA injected rats demonstrated significantly increased number of bFGF-ir astrocytes throughout the hippocampus and pyramidal neurons in CA2 after 15 days and decreased number of bFGF-ir cells after 30 and 90 days. The decrease in the number of bFGF-ir astroglia and neurons in long term after KA injection may indicate a decrease in the production of bFGF and/or number of bFGF-ir cells suggesting that protective effects of bFGF may be altered during epileptogenesis in hippocampus.  相似文献   
56.
A new method for the correction of secondary unilateral cleft lip nose   总被引:2,自引:0,他引:2  
Summary In 1982, Dibbell described a procedure to correct this distortion by rotating and advancing the nostril medially and superiorly. We used this method in our department for several years, but as Dibbell himself experienced, we didn't always obtain satisfactory results. Like many authors, I agree that the best approach for proper correction of the secondary unilateral cleft lip nose deformity is the external approach using transcolumellar incisions, because the lower lateral cartilage exposure is inadequate with Dibbell's method. I added the transcolumellar incision similar to Bardach's to solve this problem. In this paper, this combination technique will be presented and contrasted with Dibbell's and Bardach's techniques.  相似文献   
57.
58.
Depth of epidural space in children   总被引:1,自引:0,他引:1  
M. A. Hasan  MB  ChB  DA  FRCA    R. F. Howard  BSc  MB  ChB  FRCA    A. R. Lloyd-Thomas  MB  BS  FRCA   《Anaesthesia》1994,49(12):1085-1087
  相似文献   
59.
本实验就复方硅橡胶栓堵剂(CSR)对家兔输卵管上皮细胞趋微结构的影响进行了观察分析,并测定了上皮细胞内铜元素的含量变化,电镜观察表明:家充输卵管经复方硅橡胶栓堵后,其上皮细胞表面结构、细胞连接、细胞核等超微结构均未发生明显的形态改变:注药侧(右侧〕和对照侧(左侧)输卵管上皮细胞内虽有少数线粒体膨胀,但两组间无论在线粒体数目,膨胀线粒体百分率以及线粒体外膜比表面等方面均无差异(P>0.1),电镜X—时线能谱分析表明:注药侧输卵管上皮细胞内铜元素的相对含量咯高于对照组,而且铜元素多畜集于线粒体内。  相似文献   
60.
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid.  相似文献   
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