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991.
992.
Although reactive hyperemia index (RHI) predicts future coronary events, associations with intravascular ultrasound (IVUS)-assessed coronary plaque structure have not been reported. This study therefore investigated associations between RHI and IVUS-assessed coronary plaques. In 362 patients RHI was measured by noninvasive peripheral arterial tonometry and coronary plaque components (fibrous, fibrofatty, necrotic core, and dense calcium) were identified by IVUS in 594 vessel segments of the left anterior descending, circumflex, and/or right coronary arteries. RHI values <1.67 were considered abnormal. Analysis of variance was used to detect independent associations between RHI and plaque composition. Patients with an abnormal RHI had greater plaque burden (41% vs 39% in patients with normal RHI, p = 0.047). Compared to patients with normal RHI, plaque of patients with abnormal RHI had more necrotic core (21% vs 17%, p <0.001) and dense calcium (19% vs 15%, p <0.001) and less fibrous (49% vs 54%, p <0.001) and fibrofatty (11% vs 14%, p = 0.002) tissue. After adjustment for age, gender, cardiovascular risk factors, and drug therapy, abnormal RHI remained significantly associated with fibrous (F ratio 14.79, p <0.001), fibrofatty (F ratio 5.66, p = 0.018), necrotic core (F ratio 14.47, p <0.001), and dense calcium (F ratio 10.80, p = 0.001) volumes. In conclusion, coronary artery plaques of patients with abnormal RHI had a larger proportion of necrotic core and dense calcium. The association of an abnormal RHI with a plaque structure that is more prone to rupture may explain why these patients exhibit a greater risk of coronary events.  相似文献   
993.
Rhinoliths are nasal stones that result from mineralisation of salts around an endogenous or exogenous nidus within the nasal cavity. They are uncommon nasal masses and usually unilateral and single, situated in the floor of the nose. The patient typically presents with nasal obstruction, facial pain and foul-smelling nasal secretion. To the best of our knowledge, the occurrence of squamous cell carcinoma with rhinolithiasis has not been previously reported in the English-language literature. In this article, we present a 63-year-old man, who had unilateral rhinolithiasis with squamous cell carcinoma within the nasal cavity.  相似文献   
994.
The aim of this study was to investigate the effects of the application of gaseous ozone and Nd:YAG laser on glass‐fibre post bond strength. Forty‐two madibular premolar roots were cut, endodontically instrumented and irrigated with 2.5% NaOCl. Post spaces were prepared and roots were divided into three groups (n = 14). The antimicrobial pretreatment was conducted as follows: gaseous ozone, Nd:YAG laser and control (no additional disinfection methods). Scanning electron microscope analysis was made for each group (n = 2). A resin cement was used for luting the posts. For push‐out test, each root was cut horizontally (two cervical, two middle and two apical). Statistical analyses were performed with one‐way anova (α = 0.05). Fracture types were observed. There was no statistically significant difference between the groups (P > 0.05). There were statistically significant differences in cervical and apical segments of laser and control groups (P < 0.05). The disinfection of the post spaces with Nd:YAG laser and ozone had no adverse effects on bond strength of glass‐fibre post.  相似文献   
995.
The present review article is a summary of several previously published articles focusing on the aetiology behind deviations in the dental development such as malformation, agenesis, eruption deviations and abnormal resorption. The previous findings have not been compiled before and are documented in a series of new cases in this article. The evaluation of aetiology is based on histological knowledge about early dental development and new knowledge about the periodontal membrane. The article describes the different deviations in the dentition based on an analysis of ectodermal mucosa, innervation and ectomesenchyme. Focus is on the developmental fields in the jaws, determined by the course of the peripheral nerves.The article documents that the innervation of the jaws and teeth is an important aetiological factor behind deviations in dental development and dental eruption. The association of deviations in teeth with deviations in skin is also documented and demonstrated in agenesis, dental malformations and eruption deviations. Furthermore, the interrelationship between findings in the primary and permanent dentitions is described, specifically in resorption.The analysis distinguishes between deviations in a limited field and deviations occurring generally in the dentition. Furthermore, the bilateral occurrence of deviations in contralateral fields is described.Conclusively, the article presents advice regarding conditions that should be included in aetiology-based diagnostics.  相似文献   
996.
Oral Diseases (2012) 18 , 802–808 Objective: The aim of conducting this study was to evaluate the effect of zoledronic acid (ZA) on the new bone formation (NBF) after the insertion of a titanium dental implant, which is very popular treatment in dentistry. Study Design: Twelve New Zealand white rabbits were used in this study. The rabbits were divided in two groups. ZA was systemically administered to the study group. Titanium implants were placed to the left and right tibias of the rabbits. Results: The data from the ZA group revealed a statistically significant increase in the bone mineral content and the bone mineral density. A non‐decalcified histomorphometric examination conducted on the study group revealed a significant increase of NBF and bone‐implant contact (BIC) at 2 and 4 weeks. Conclusion: A single dose of systemic ZA administration increases the rate of NBF and augments the quality of the bone.  相似文献   
997.
Editorial     
It has been proven that the jaw rehabilitation not only has a crucial role in treatment of both trismus and mandibular hypomobility but also in the rehabilitation of surgical conditions of the temporomandibular joint and the jaw.(1) Today, the commercially available jaw motion rehabilitation systems are specifically designed to treat these conditions.(2) These systems utilize repetitive passive motion and stretching to restore mobility and flexibility of the jaw musculature, associated joints and connective tissues. Major advantages of these systems are that they reduce patients' anxiety by allowing them to control the extent and length of each stretching and provide passive motion for effective jaw rehabilitation therapy allowing patients to perform their necessary therapy while continuing in their daily life.(3) However, these systems are very expensive and mostly unavailable in our country. So, a new alternative jaw motion rehabilitation device 'The Okbite' was developed recently in our hospital (Fig. 1). It is simply adapted from the commercially available nasal specula. The blades of the specula are cut distally and metal bite pads are attached to these sites. The lower bite pad was placed posteriorly and curved anatomically. This device can be produced in a custom-made form according the occlusal pattern and the size of the mandible of the patient. The metal bite pads are covered with plaster bandage by the patient for a soft bite. In our practice, we used this device for the rehabilitation of total temporomandibular joint prosthesis, temporomandibular gap arthroplasties and temporomandibular joint disorders with great success. It costs nearly 1/50 of the commercially available jaw motion rehabilitation systems with almost equal outcomes of pain relief and total mouth opening. The major disadvantage of this system is that it can mimic the anatomical motion pattern of the mandible to a limited extend. We propose the application of this Okbite system, which provides jaw rehabilitation in such conditions.  相似文献   
998.
The current treatment philosophy is to prevent and detect dental disease at the earliest stage in order to avoid invasive treatment. With the current understanding of the nature of dental disease and its process, the treatment philosophy is now changing to a more conservative approach and the concept of minimal intervention is gaining popularity in modern dentistry throughout the world. It is now established that demineralized but non-cavitated enamel and dentine can be healed and traditional surgical approach of drilling and filling may no longer be necessary as this only treats the symptoms of the disease and not the cause. However, when surgical intervention is indicated, the least invasive techniques such as preventive resin restoration and minimal cavity preparation are utilized. The aim of this article is to give dental professionals an overview of the concepts of minimal intervention dentistry and recent innovations in dental technology in both the diagnosis and treatment of dental caries.  相似文献   
999.
Elucidation of the molecular mechanisms of leukemogenesis is important for a better understanding of the prognosis of acute lymphoblastic leukemia (ALL). Studies have shown that the expression of upregulated gene 4 (URG4), which promotes cell growth and survival, is increased in different types of carcinomas including hepatocellular carcinoma, gastric cancer and osteosarcoma. Similarly, higher expression of URG4 and cyclin D1 gene might promote proliferation of the blast cells by causing escape from the G1 checkpoint and entry into the S phase. This study reports the high expression level of URG4 in 2 high-risk ALL patients for the first time in the literature. In conclusion, the higher expression of URG4 in our 2 patients suggests that URG4 might be involved in leukemogenesis. Future studies with a large number of high-risk ALL patients and cell culture studies are needed to demonstrate the exact role of URG4 in leukemogenesis.  相似文献   
1000.
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