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61.
To investigate the efficacy of Er,Cr:YSGG (erbium,chromium:yttrium scandium gallium garnet) laser irradiation in root canal preparation and to evaluate its effect on eruption of rat incisors after disturbance of the enamel organ in the pulp, 20 canals of lower left incisor teeth were prepared by K-files followed by Er,Cr:YSGG laser irradiation, and 20 canals of right incisors were subjected to K-files only (control). At 1 week after irradiation, both sides of incisors erupted at the same level from the gingival margin. Histological findings showed that laser irradiation produced a slightly larger damage in the pulp than that of control. Scanning electron microscope observation revealed that laser-treated surface revealed a rough, irregular, and very clean surface; there was almost no evidence of debris or smear layer, and dentinal tubules were opened. Adequate power of Er,Cr:YSGG laser irradiation is effective in root canal preparation without disturbance of the eruption.  相似文献   
62.

Background

Prior reports have suggested that the design of the Promus Element stent is prone to longitudinal stent deformation (LSD). However, little is known about the clinical and angiographic outcomes of Promus Element stent axial deformations when implanted in unrestricted coronary lesions.

Method and Results

Two independent reviewers retrospectively evaluated the procedure steps of 961 Promus Element stent (833 de novo lesions in 494 consecutive patients) implanted in unrestricted coronary lesions, between February 2012 and March 2013, and compared the prevalence, predictors, and the mid‐term clinical and angiographic outcomes between lesions with and without stent deformation. Fifteen stents (1.56%) with LSD were observed (95% confidence interval [CI]: 0.78–2.34%). The proximal edge of the stent was deformed in 13 stents (86.6%). Ostial stenting (Adjusted Odds ratio [OR]: 9; 95%CI: 2.27–33.3; P = 0.002), and bifurcation lesions (Adjusted OR: 3; 95%CI: 1.03–8.8; P = 0.04) were independently associated with the occurrence of stent deformation. LSD led to unplanned stenting in (53%, 8 of 15) of the deformed stents, which consumed larger contrast volume and longer fluoroscopy time. At 8‐month follow‐up, there was no significant difference in binary restenosis rate and target lesions revascularization between both groups (P = 0.98, and P = 0.56, respectively), while death occurred in six patients of the non‐LSD group (1.36%, 6 of 440) and none in the LSD group. All patients of the LSD group had no major adverse clinical events at 8‐month follow‐up.

Conclusions

Axial stent deformation in Promus Element platform is an infrequent event, occurs following manipulation of the interventional tools. Other than unplanned stenting, the LSD was not associated with any adverse clinical events at 8‐month follow‐up.
  相似文献   
63.
64.
目的:对目前昭和大学齿学部基础研究中常用的Nd∶YAG激光工作参数进行超微结构水平研究。方法:应用脉冲Nd∶YAG激光对经根管器械预备后的36枚离体单根管牙根尖孔区予以未涂墨或涂墨20pps1W/2s、2W/1s、3W/05s各接触式照射1次~3次,以扫描电镜观察根管壁的结构改变。结果:当工作参数为20pps1W/2s或2W/1s未涂墨1次~3次照射或涂墨1、2次照射时或3W/05s未涂墨3次照射或涂墨1次~3次照射时,Nd∶YAG激光不仅能清除根尖孔区根管壁上的碎屑及玷污层,而且不致破坏根尖孔狭部结构。结论:本实验在超微结构方面为脉冲Nd∶YAG激光对根尖孔区照射选择适宜的工作参数提供了可靠依据,Nd∶YAG激光可望成为根管治疗学的新手段。  相似文献   
65.
OBJECTIVE: The purpose of this study was to evaluate the intensity of fluorescent light reflected from cavity wall dentin, after dentin stained by an experimental caries detecting liquid was removed. BACKGROUND DATA: The conventional caries detecting liquid tends to penetrate dentin too deeply. On the other hand, DIAGNOdent has gradually gained recognition and established itself as a caries detection device using a laser beam. METHOD: An experimental caries staining liquid or the conventional caries staining liquid was applied in the same cavity to observe for differences in dye penetration. Intensity of fluorescence reflected from treated dentin was measured by DIAGNOdent. RESULTS: The mean DIAGNOdent value after removing the tooth substance stained by the experimental liquid was 17.9+/-4.1, compared with 7.7+/-2.7 by conventional one. CONCLUSION: Light intensity evaluation of laser-induced fluorescence suggested that the experimental caries detecting liquid did not penetrate the dentin which should be preserved, hence avoiding overtreatment.  相似文献   
66.
67.
Tumor suppressor in lung cancer-1 (TSLC1) is an intercellular adhesion molecule of the immunoglobulin superfamily. There is little information regarding the developmental expression profiles. In an attempt to clarify the distribution of TSLC1 proteins in mouse embryos tissue by immunohistochemistry, it was found that the TSLC1-specific signals were detected in the tooth germ as early as bud stage. The signals of TSLC1 were in the enamel epithelium at the cap stage, and became restricted to ameloblasts during the transition to and throughout the bell stage. In contrast, the signals for E-cadherin, which is important in odontogenesis, were distributed in all the components of the ectoderm-derived germ at any stage. In addition, E-cadherin preferred to locate on the basal membrane of ameloblasts, whereas TSLC1 preferred the lateral. And in further contrast, all the ameloblastomas examined were positive for E-cadherin (18/18) whereas all but one was negative for TSLC1 (1/18). These results indicate that TSLC1 is a novel interameloblast adhesion molecule that may be downregulated during ameloblastic tumorigenesis.  相似文献   
68.
OBJECTIVE: The purposes of this study were to investigate cavity surfaces morphologically, and compare microleakage at cavities prepared by Er:YAG laser after composite resin restoration versus conventional mechanical treatment in human primary teeth in vitro. BACKGROUND DATA: There have been few reports on microleakage at cavities prepared by Er:YAG laser irradiation. MATERIALS AND METHODS: A total of 30 cavities (class V) in human primary teeth were used. Half of the cavities were prepared by an Er:YAG laser system at 300 mJ pulse energy and 4 Hz, and the other half were prepared with a high-speed diamond bur. Five cavities from each group were investigated by scanning electron microscopy (SEM) and histopathological examination. Remaining cavities were filled with a composite resin without an acid-etching technique and then subjected to microleakage test in 0.6% rhodamine B solution under thermocycling. RESULTS: Microleakage (score: 2.45 +/- 1.07) at cavities prepared by laser was significantly less than that by bur (score: 1.30 +/- 0.95; p < 0.05). SEM observation showed that, compared with the relatively flat appearance of cavities prepared by bur, cavity margins prepared by laser were irregular but there was almost no smear layer at the cavity walls. CONCLUSION: It can be concluded that cavity surfaces prepared by Er:YAG laser are irregular, but microleakage at cavities prepared by the laser after filling with composite resin is better than that by mechanical bur using the dye penetration method.  相似文献   
69.
A 69-year-old female suffering from third-degree atrioventricular block with syncope underwent permanent pacemaker implantation. However, she developed shortness of breath 2 months after the implantation. Blood tests revealed elevated levels of LDH, CRP, BNP, and SIL-2R. Transthoracic echocardiography showed thickened left and right atrial walls with mild pericardial effusion. A diagnosis was made based on a CT scan and histology. Although most primary cardiac malignant lymphomas are associated with a poor prognosis, the patient was treated successfully with chemotherapy.  相似文献   
70.
Enhanced locomotory activity (ELA), such as wandering, is a normal behavior that occurs at the end of the larval stage in lepidopteran (butterflies and moths) insects. Baculovirus infection can also induce ELA in lepidopteran larvae. The belief is that the virus induces this behavior to increase its transmission [Goulson, D. (1997) Oecologia 109, 219-228]. Here we show that a baculovirus-encoded protein tyrosine phosphatase (PTP) gene (ptp) induces ELA that is activated by light. ELA was induced in silkworm Bombyx mori infected with the baculovirus B. mori nucleopolyhedrovirus (BmNPV) beginning at approximately 3.75 days postinfection (p.i.) and continued until 4.75 days p.i. The intensity of the ELA was dramatically reduced immediately before death at 5.25 days p.i. Light activated the intensity of the ELA by approximately 3-fold, and larvae with ELA showed positive phototropism. ELA was not induced in larvae of B. mori infected with a BmNPV ptp knockout mutant (BmPTPD). However, when a silkworm-derived ptp gene (Bmptp-h) was inserted into BmPTPD, ELA was partially recovered. Bmptp-h was identified from silkworms at 2 days after the start of the natural wandering stage. The deduced amino acid sequence of Bmptp-h showed 48.2% identify (80.7% similarity) to the deduced amino acid sequence of BmNPV ptp. On the basis of the high homology and larval stage at which Bmptp-h was isolated, we postulate that the modern baculovirus may have acquired its ptp gene from an ancestral host and that this gene was selectively maintained because it increases virus transmission.  相似文献   
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