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1.
AIM:To evaluate the outcome of chronic hepatitis B(CHB)in children with or without malignancies.METHODS:Twenty four children(15 boys and 9 girls)with malignancies,followed up by the pediatric gastroenterology outpatient clinic for CHB between January 2000 and December 2013,were enrolled in the study(Group 1).Group 2 was formed with twenty five children(11 girls and14 boys)diagnosed with CHB without malignancies.The data from the patients’records were compared between the two groups.RESULTS:Hepatitis B e antigen(HBe Ag)/anti HBe seroconversion was observed in 3 patients(12.5%)in group 1 and 15 patients(60%)in group 2,with annual seroconversion rates of 1.61%and 16.6%,respectively,and the difference was significant(P0.01).One patient(6.6%)in Group 1 and 9 patients(53%)in Group 2 showed HBe Ag/anti HBe seroconversion after treatment and the difference between the two groups was significant(P0.06)Loss of hepatitis B surface antigen was observed in one patient in each of group1 and 2.No clinical,laboratory and imaging findings of liver disease were observed in any of the patients at the end of the study.CONCLUSION:HBe Ag/anti HBe seroconversion rate was lower in patients who had recovered from cancer.  相似文献   
2.
BACKGROUND: Severe congenital neutropenia (SCN), also known as Kostmann syndrome, was originally reported as an autosomal recessive disease of neutrophil production. The disease is characterized by a maturation arrest of neutrophil precursors at the promyelocytic stage of differentiation and by extremely low levels of mature neutrophils in peripheral blood. METHODS: A 6-year-old male presented with a complaint of gingival swelling and bleeding, and swelling at the left side of his face. Upon clinical examination, severe inflammation of all gingival tissues was apparent, and a periapical abscess with mobility was noted on the left mandibular second molar. Medical and dental histories revealed numerous recurrent bacterial infections associated with oral and non-oral tissues. His medical history with recurrent infections led us to evaluate his 3-year-old sister to determine the status of her oral health. Inflammation of her oral tissues and recurrent bacterial infections were apparent. Their consanguineous parents were in good health. To assist in identifying possible systemic diseases underlying the inflammatory situation in the siblings, consultations were requested from the Pediatric Hematology Department at Selcuk University and Pediatric Oncology Department at Gulhane Military Medical Academy. RESULTS: Based on absolute neutrophil count (< or =200/mm(3)) and bone marrow aspiration findings consistent with early maturation arrest in myelopoiesis, the cases were diagnosed as SCN. No chromosomal abnormality was detected upon cytogenetic examination. Sequencing analysis also revealed no mutation in the neutrophil elastase or growth factor independent-1 (GFI-1) genes in these patients. Severe periodontal disease, attachment loss, and mobility for over 50% of the deciduous teeth were noted. Within 6 months, the male sibling lost all of his deciduous teeth due to periapical and periodontal infections. His sister presented with tooth mobility for all mandibular incisors. Monthly visits, including scaling, polishing, and 0.2% chlorhexidine digluconate irrigation were performed to support their oral hygiene and to avoid recurrent oral infections. We have been able to stabilize these patients' periodontal conditions during a 2-year follow-up period. CONCLUSION: This case report emphasizes the role of periodontists and pediatric dentists in the diagnosis of diseases linked with neutrophil and other systemic disorders and highlights the need to optimize the health of oral tissues with regular appointments.  相似文献   
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BACKGROUND: Papillon-Lefèvre Syndrome (PLS) is an autosomal recessive disease characterized by palmoplantar hyperkeratosis and severe periodontitis affecting both primary and secondary dentitions. Cathepsin C (CTSC) gene mutations are etiologic for PLS. The resultant loss of CTSC function is responsible for the severe periodontal destruction seen clinically. METHODS: A 4-year-old female (case 1) and her 10-year-old sister (case 2) presented with palmoplantar skin lesions, tooth mobility, and advanced periodontitis. Based on clinical findings, the cases were diagnosed with PLS. Mutational screening of the CTSC gene was conducted for the cases, and their clinically unaffected parents and brother. Biochemical analysis was performed for CTSC, cathepsin G (CTSG), and elastase activity in neutrophils for all members of the nuclear family. The initial treatment included oral hygiene instruction, scaling and root planing, and systemic amoxicillin-metronidazole therapy. RESULTS: CTSC mutational screening identified a c.415G>A transition mutation. In the homozygous state, this mutation was associated with an almost complete loss of activity of CTSC, CTSG, and elastase. Although monthly visits, including scaling, polishing, and 0.2% chlorhexidine digluconate irrigation were performed to stabilize the periodontal condition, case 1 lost all her primary teeth. In case 2, some of the permanent teeth could be maintained. CONCLUSIONS: This report describes two siblings with a cathepsin C gene mutation that is associated with the inactivity of cathepsin C and several neutrophil serine proteases. The failure of patients to respond to periodontal treatment is discussed in the context of these biological findings.  相似文献   
5.
Two hundred eight patients, who applied to the Department of Pedodontics, Dental School, Dicle University between 1995 and 1998, were evaluated in terms of permanent teeth fracture. The aim of this retrospective study was to investigate the probable causes of the trauma, the effects of age and gender on dental trauma, prevalence of fracture types, and distribution of fracture type according to arch. It was observed that the falls or collisions were the main causes. It was also determined that the age group most frequently suffering fractures was ages 9 to 11 years. The majority of the patients were male. The enamel-dentin-pulp-type fracture and those causing the tooth to become nonvital were the most prevalent, and the majority of the fractures were observed in maxillary central teeth.  相似文献   
6.
PURPOSE: The purpose of this study was to evaluate the clinical performance of surface-retained adhesive composite fixed partial dentures reinforced by an ultra-high molecular weight polyethylene (UHMWP) fiber (Ribbond THM). MATERIALS AND METHODS: Twenty-three surface-retained fiber reinforced composite (FRC) fixed partial dentures (FPD) were placed by two operators in 23 patients, each with a single missing tooth. The restorations included prefabricated composite resin pontics, and no preparations were done on the lingual surfaces of the abutment teeth. The patients were recalled for examinations every year for up to 3 years. Restorations were evaluated directly using the modified Ryge criteria. The minimum observation period was 1 year and the maximum observation period was 3 years. RESULTS: At baseline, 23 restorations were graded as Alpha for all parameters. At one year and two years (n = 21), three Bravos for wear resistance and surface texture/gingival inflammation and two Bravos for color match were observed. Twenty-one of 23 restorations were retained at the end of two years (91.3%) and 78.3% were retained after a maximum of 3 years. CONCLUSION: The results of this clinical study suggestthat UHMWP FRC FPDs are quite acceptable at least forthree years. However, further clinical investigations are still needed for improved long-term clinical performance.  相似文献   
7.
STATEMENT OF PROBLEM: The degree to which pulpal pressure may affect bond strength of complete cast crowns is unknown. PURPOSE: The aim of this in vitro study was to evaluate the effect of simulated pulpal pressure on the tensile bond strength of complete cast crowns luted with 2 different cements. MATERIAL AND METHODS: Forty-eight human mandibular canine teeth were cleaned and stored in saline solution. The crowns were prepared by 1 investigator, and standardization of the preparation was accomplished by fixing a dental handpiece in a parallelometer. Uniform grooves, 0.5 mm in depth, were prepared with burs with depth guides. The complete crowns were prepared with a 0.5-mm shoulder margin. Teeth were randomly divided into 2 groups of 24 teeth each (Group I and Group II). In Group I, bonding and tensile test procedures of the teeth were carried out under simulated pulpal pressure (15 cm of saline solution). In Group II, simulated pulpal pressure was not used. The roots were removed 1 mm below the cementoenamel junction to create direct communication with the pulp chamber. The remaining pulpal tissues were carefully removed, and crowns were embedded in acrylic resin. The acrylic resin was then penetrated by a stainless steel tube that connected the pulp chamber and the barrel of a disposable plastic 5-ml syringe. The pulp chambers were filled with physiological saline solution under elevated pressure to locate the area of greatest permeability on the dentinal surface. Crowns were cast (Co-Cr alloy) with a 20-mm bar to allow testing of the bond strength. Each of the 2 groups were further divided into 2 luting cement groups of 12 each (Group I, A and B, and Group II, A and B). Group IA/IIA and Group IB/IIB specimens were luted with a polycarboxylate luting cement (Poly-F Plus) and an adhesive luting cement (Superbond C&B), respectively. After storage in distilled water for 24 hours, all specimens were subjected to a tensile bond test in a universal testing machine at a crosshead speed of 0.5 mm/min until failure. The maximum load at fracture (Newton) was recorded. The results were then evaluated with 2-way analysis of variance and Tukey's honestly significant difference tests (alpha=.05). RESULTS: Simulated pulpal pressure increased the bond strength of cast complete crowns cemented with an adhesive luting agent (P=.01). No significant difference was found in the bond strength of complete cast crowns cemented with polycarboxylate cement with or without pulpal pressure. Superbond C&B adhesive luting agent showed significantly higher bond strength values for Group I (388.9+/-32.7) and Group II (300.9+/-66.8), when compared with polycarboxylate cement for Group I (221.3+/-17.3) and Group II (186.8+/-38.5) (P=.001). CONCLUSION: Simulated pulpal pressure had a positive effect on the retention of complete cast crowns when cemented with Superbond C&B adhesive luting agent. Superbond C&B significantly increased the retention of crowns in either the presence or absence of pulpal pressure.  相似文献   
8.
Provisional restorations are generally necessary to restore lost function and esthetics during the implant integration period. This article describes the fabrication of an esthetic, economic, and conservative bonded provisional fixed partial denture for a patient restored with implants. A reinforcing polyethylene ribbon was used to bond the natural lateral incisors to the adjacent teeth. An acceptable esthetic outcome was obtained, and the result was satisfactory to the patient.  相似文献   
9.
The purpose of this in vitro study was to evaluate two commonly used gutta-percha solvents for their effectiveness in dissolving several types of root canal sealers. Seven different sealers (AH26, AH Plus, Diaket, Roekoseal, Sankin Apatite Root Sealer, Sealapex, and Sultan U/P) were used in this study. After mixing according to the manufacturers' directions, each material was syringed into 30 glass capillary tubes, and a total of 210 tubes were placed in a humidifier at 37 degrees C for one week to allow the materials to set completely. Each group of 30 tubes, obturated with one type of sealer, was then randomly divided into three subgroups, including 10 tubes each. Chloroform was used in the first ten tubes from each sealer group. Halothane was used for the second group. In the last group, the sealer was removed with files, without using any solvent. The time necessary to pass a file through to the end of the tube was recorded for each sample in seconds. Results were analyzed using one-way analysis of variance. Sealapex did not set at all unless in contact with air. Roekoseal did not adhere to the glass capillary tubes, and was therefore easily removed from the tube in all samples. AH26 and AH Plus root canal sealers tightly adhered to the tube walls, so none of the techniques were effective in removing them from the tubes within 30 min. Diaket root canal sealer was easily removed using solvents (P < 0.05). There was no advantage in using solvents to remove Sankin Apatite Root Sealer (P > 0.05). Solvents were found to be very effective in dissolving the Sultan U/P root canal sealer (P < 0.05).  相似文献   
10.
STATEMENT OF PROBLEM: Inlay-retained resin-bonded fixed partial dentures (RBFPDs) are conservative prosthetic restorations; however, their resistance to fracture is not clear. PURPOSE: The purpose of this study was to compare fracture loads of posterior complete coverage metal-ceramic restorations with all-ceramic inlay-retained RBFPDs. MATERIAL AND METHODS: Thirty-two posterior ceramic RBFPD restorations were divided into 4 groups (n=8): (1) Complete metal-ceramic fixed partial dentures (MC-FPDs) fabricated of Ni-Cr-based alloy (Wirolloy) and veneered with a ceramic (IPS d.SIGN) as the control group; (2) inlay-retained metal-ceramic (MC RBFPDs) with the same materials as the control; (3) inlay-retained lithium disilicate (LD) glass-ceramic (IPS Empress 2) RBFPDs; and (4) inlay-retained zirconia-based (Z) ceramic (Cercon) RBFPDs. Control specimens were prepared to receive conventional complete MC-FPDs designed to include a 1.3-mm-circumferential, 90-degree flat shoulder with rounded angles. Inlay-retained RBFPD specimens were prepared with 2-mm occlusal reduction but without bevels at the occlusal or gingival margins. Specimens were loaded and fracture loads (N) measured at fracture with a universal testing machine at a crosshead speed of 1.0 mm/min and 250 kgf load cell. Data were analyzed with 1-way ANOVA and Duncan test (alpha=.001). RESULTS: Fracture loads (mean +/- SD) were greatest for control specimens (1318.43 +/- 211.00 N) and Z-RBFPD (1247.70 +/- 262.51 N) specimens as compared to MC-RBFPD or LD-RBFPD (P < .001). MC-RBFPD exhibited the next highest fracture loads (958.01 +/- 194.29 N), and LD-RBFPD exhibited the significantly lowest values (303.23 +/- 92.54 N) of the materials tested (P < .001). CONCLUSION: Inlay-retained zirconia-based ceramic RBFPDs demonstrated the greatest fracture resistance among all inlay-retained restorations tested.  相似文献   
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