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91.
Odontomas are the most common type of odontogenic tumor and are generally asymptomatic. The purpose of this paper was to describe the case of a complex odontoma in a patient who had asymptomatic swelling in the central maxillary region, along with unerupted central and lateral incisors. In this case, surgical excision of the lesion was performed and an iliac bone graft was introduced into the defect area with a titanium mesh covering up the grafted harvesting bone. After 2 years of followup, no recurrence was identified. Patient followup is still in progress to evaluate bone graft resorption, and the patient awaits complete bone development. Oral rehabilitation with an osseointegrated titanium implant is expected in the future. An option of the large complex odontoma treatment is discussed.  相似文献   
92.
This work reports the preparation of several amino alcohols condensed with d-arabinose, d-glucose, and d-galactose derivatives. These compounds were evaluated in vitro for their cytotoxicity and ability to decrease nitric oxide production in J774A.1 cells. Arabinofuranoside derivatives 5a, 5b and 5c showed a significant inhibition of nitric oxide production (>80% at 5 μg/mL), while the galactopyranoside derivative 8d showed a notable nitric oxide inhibitory activity (126% at 0.5 μg/mL).  相似文献   
93.
BACKGROUND: This study evaluated the effect of periodontal therapy plus amalgam overhang removal (PT+AOR) on periodontal status and the presence of Actinobacillus actinomycetemcomitans and Streptococcus mutans and compared two microbiological sampling techniques. METHODS: Molar teeth with Class II overhang restorations were selected as the test group, and homologous sound teeth were selected as the control group. Periodontal probing depth (PD), clinical attachment level (CAL), and plaque and gingival indices were measured, and restorations were evaluated using radiographs and clinical exploration at baseline (T1) and 90 days after PT+AOR (T2). Microbial samples were taken with dental floss and paper points at T1 and T2. S. mutans and A. actinomycetemcomitans were detected using culture and commercial kits. RESULTS: Mean values of plaque and gingival indices did not show statistically significant differences between test and control teeth between T1 and T2. At T2, the mean CAL decreased among test teeth, and the number of test teeth positive for A. actinomycetemcomitans showed a decrease, whereas positive samples for S. mutans increased. At T1, an association between the two sampling techniques for both bacteria was found. At T2, dental floss presented low sensitivity values for A. actinomycetemcomitans, whereas paper points showed low sensitivity for S. mutans. CONCLUSIONS: PT+AOR showed a beneficial effect on clinical parameters and a decrease of A. actinomycetemcomitans. At T1, both sampling techniques showed appropriate results. At T2, the use of paper points was a more sensitive sampling technique for isolate A. actinomycetemcomitans, whereas dental floss was found to be an alternative sampling method for isolate S. mutans.  相似文献   
94.
Acid etching promotes microporosities on enamel surface, which provide a better bonding surface to adhesive materials. The purpose of this study was to comparatively analyze the microstructure of enamel surface after etching with 37% phosphoric acid or with two self-etching primers, Non-rinse conditioner (NRC) and Clearfil SE Bond (CSEB) using scanning electron microscopy. Thirty sound premolars were divided into 3 groups with ten teeth each: Group 1: the buccal surface was etched with 37% phosphoric acid for 15 seconds; Group 2: the buccal surface was etched with NRC for 20 seconds; Group 3: the buccal surface was etched with CSEB for 20 seconds. Teeth from Group 1 were rinsed with water; teeth from all groups were air-dried for 15 seconds. After that, all specimens were processed for scanning electron microscopy and analyzed in a Jeol 6100 SEM. The results showed deeper etching when the enamel surface was etched with 37% phosphoric acid, followed by NRC and CSEB. It is concluded that 37% phosphoric acid is still the best agent for a most effective enamel etching.  相似文献   
95.
96.
PURPOSE: Resistance to topoisomerase (topo) I inhibitors has been related to down-regulation of nuclear target enzyme, whereas sensitization to topo II inhibitors may result from induction of topo II by topo I inhibitors. Here, we evaluated a sequence-specific administration of a topo I inhibitor followed by a topo II inhibitor. EXPERIMENTAL DESIGN: Twenty-five patients with advanced or metastatic malignancies were treated with increasing doses (0.75, 1.0, 1.25, 1.5, 1.75, or 2.0 mg/m(2)) of 9-nitrocamptothecin (9-NC) on days 1 to 3, followed by etoposide (100 or 150 mg/d) on days 4 and 5. At the maximally tolerated dose, 20 additional patients were enrolled. The median age was 60 years (range, 40-84 years). Endpoints included pharmacokinetic analyses of 9-NC and etoposide, and treatment-induced modulations of topo I and II expression in peripheral blood mononuclear cells. RESULTS: Neutropenia, thrombocytopenia, nausea, vomiting, diarrhea, and fatigue were dose-limiting toxicities and occurred in six patients. Despite a median number of four prior regimens (range 1-12), 2 (4%) patients had an objective response and 13 (29%) patients had stable disease. In contrast to the expected modulation in topo I and IIalpha levels, we observed a decrease in topo IIalpha levels, whereas topo I levels were not significantly altered by 9-NC treatment. CONCLUSIONS: Sequence-specific administration of 9-NC and etoposide is tolerable and active. However, peripheral blood mononuclear cells may not be a predictive biological surrogate for drug-induced modulation of topo levels in tumor tissues and should be further explored in larger studies.  相似文献   
97.
98.
Background Nasopalatine duct cyst (NDC) is the most common non-odontogenic cyst in the oral cavity. Clinically it is not difficult to suspect these lesions based on clinical and radiographic appearance. However, the histopathological diagnosis may be difficult due to the broad morphological diversity of these lesions. The objective was to analyze the clinicopathological features of NDCs diagnosed in two oral and maxillofacial pathology services in the Brazilian northeast.Material and Methods A retrospective clinicopathologic study was performed. A total of 18,121 clinical records of oral lesions from two oral and maxillofacial pathology services in Brazil were analyzed (2000-2020). All NDCs cases were revised and demographic, clinical, radiographic, and histopathological data were collected.Results Among 18,121 diagnoses in the oral pathology services, 45 (0.2%) were NDCs. The series comprises 24 males (53.3%) and 21 females (46.7%), with a mean age of 43.2 years-old. Most lesions were asymptomatic (n = 27, 60%) with an mean size of 2.1 cm. Microscopically, the non-keratinized stratified squamous epithelium was the most common (66.7%). However, in 88.9% of cases, the epithelial lining was varied and composed of two or more types of epithelium. There was no significant association between the type of epithelium and the size of the cysts (p = 0.389). Nerve, blood vessels, hemorrhage, and chronic inflammatory infiltrate were commonly observed. In contrast, there was a low frequency of mucous glands, sebaceous glands, cholesterol clefts, and multinucleated giant cells.Conclusions The clinical, radiographic, and microscopic findings observed in this study are similar to those reported in the literature. Due to the morphological diversity of NDC, it is needed to correlate its histopathological features with the clinical and radiographic findings to establish a correct diagnosis. Key words:Oral cavity, oral pathology, nonodontogenic cysts, diagnosis.  相似文献   
99.
The aim of this study was to evaluate the acaricidal activity of eugenol, with different solubilizations and concentrations, on Rhipicephalus microplus and Dermacentor nitens larvae and to determine the lethal time. The study consisted of four experiments, and the mortality was assessed using the larval packet test with adaptations. The mortality observed in the first experiment was 100?% for all the groups treated with eugenol solubilized in different solvents. In the second, the hydroethanolic formulation of eugenol was used, and the mortality rates for R. microplus and D. nitens was 100?% starting from the concentration of 5.0?μl/ml. In the third experiment, the mortality was 100?% for larvae of both R. microplus and D. nitens after 1?h of contact. And in the fourth experiment, the mortality was above 90?% and statistically similar (p?>?0.05) for the four methods the test evaluated.  相似文献   
100.
The acaricidal activity of three thymol formulations was investigated at five concentrations (1.25, 2.5, 5.0, 7.5, and 10.0?mg/ml) on Rhipicephalus microplus larvae, and the behavior of its solubility in these formulations was analyzed. The thymol was dissolved in distilled water plus 1?% dimethylsulfoxide as adjuvant under two heating regimes (water bath in formulation 1 and hot plate in formulation 2) as well as without heating in 50?% ethanol and 50?% water (v/v). The acaricidal activity was assessed by the modified larval packet test, and the solubilization behavior was investigated by ultraviolet–visible spectroscopy, based on the Beer–Lambert law. With formulations 1 and 2, the mortality was greater than 95?% starting at the thymol concentrations of 5.0 and 7.5?mg/ml, respectively, while with formulation 3, this mortality level was reached starting at a concentration of 2.5?mg/ml, showing that the addition of ethanol in the solution enhanced the acaricidal action of thymol. This result was supported by the LC 90 values, which were 3.3, 2.4, and 1.6?mg/ml of thymol for formulations 1, 2, and 3, respectively. This result is related to the better solubility of thymol in the hydroethanolic formulation, since the spectroscopic analysis revealed that the thymol dissolved more completely in this formulation. This fact was evident once the R 2 obtained from the linear regression analysis of the relation absorbance × concentration of the formulations 1, 2, and 3 approached the optimal value (R 2?=?1) in the following sequence: 1, 2, and 3 (0.717, 0.901, and 0.968, respectively).  相似文献   
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