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1.
BackgroundIn shoulder arthroplasty, bone resorption around the stem can lead to stem loosening and makes surgery difficult at the time of revision. Proximal bone resorption after reverse shoulder arthroplasty can cause instability because of a decrease of deltoid wrapping effect. As factors of the stem itself, such as stem coating, shape, length, and use of bone cement, may also affect bone resorption, a single-stem model should be used to compare bone resorptions between different pathologies and surgical procedures. However, to date, a few reports have compared these differences in detail using a single-stem model. Therefore, we investigated the prevalence and location of humeral bone resorption in a single-stem model.MethodsThe study included 100 shoulders that underwent anatomical total shoulder arthroplasty (TSA) or humeral head replacement (HHR) with a single uncemented humeral stem from 2008 to 2018. The patients were 31 men and 69 women. The mean age at surgery was 72.9 years (range, 41-86 years). The patients were divided into three groups: especially, 25, 61, and 14 shoulders received TSA for primary osteoarthritis without rotator cuff tears (TSA group), HHR using an anatomical head with rotator cuff repair for cuff tear arthropathy (CTA) (HHR group), and HHR using a CTA head without rotator cuff repair (CTA group), respectively. Patients were monitored for a mean of 56 months (range, 12-98 months). The location of bone resorption was divided into seven zones as follows: zone 1, greater tuberosity; zone 2, lateral diaphysis; zone 3, lateral diaphysis beyond the deltoid tuberosity; zone 4, tip of the stem; zone 5, medial diaphysis beyond the deltoid tuberosity; zone 6, medial diaphysis; and zone 7, calcar region. The degree of bone resorption was classified from grade 0 to 4.ResultsBone resorption of grade 3 or higher was significantly more frequent at the greater tuberosity in the HHR and CTA groups (P < .001 and P < .001, respectively) than that in the TSA group. Grade 4 bone resorption was significantly more frequent in the CTA than that in the TSA and HHR groups in zone 1 (P = .016 and P = .041, respectively).ConclusionThe state of attachment of the rotator cuff to the greater tuberosity might affect bone resorption at the greater tuberosity, such as the greater tuberosity after shoulder arthroplasty. In cases of shoulder arthroplasty for arthropathy with rotator cuff tear, performing rotator cuff repair might prevent bone resorption.Level of evidenceLevel IV; Prognosis Study  相似文献   
2.
International Journal of Clinical Oncology - With the development of poly(ADP-ribose) polymerase inhibitors, the treatment of advanced ovarian cancer is changing dramatically. The purpose of this...  相似文献   
3.
To obtain baseline data for cervical cancer prevention in Japan, we analyzed human papillomavirus (HPV) data from 5045 Japanese women aged less than 40 years and diagnosed with cervical abnormalities at 21 hospitals during 2012‐2017. These included cervical intraepithelial neoplasia grade 1 (CIN1, n = 573), CIN2‐3 (n = 3219), adenocarcinoma in situ (AIS, n = 123), and invasive cervical cancer (ICC, n = 1130). The Roche Linear Array was used for HPV genotyping. The HPV type‐specific relative contributions (RCs) were estimated by adding multiple infections to single types in accordance with proportional weighting attributions. Based on the comparison of type‐specific RCs between CIN1 and CIN2‐3/AIS/ICC (CIN2+), RC ratios were calculated to estimate type‐specific risks for progression to CIN2+. Human papillomavirus DNA was detected in 85.5% of CIN1, 95.7% of CIN2‐3/AIS, and 91.2% of ICC. Multiple infections decreased with disease severity: 42.9% in CIN1, 40.4% in CIN2‐3/AIS, and 23.7% in ICC (P < .0001). The relative risk for progression to CIN2+ was highest for HPV16 (RC ratio 3.78, 95% confidence interval [CI] 3.01‐4.98), followed by HPV31 (2.51, 1.54‐5.24), HPV18 (2.43, 1.59‐4.32), HPV35 (1.56, 0.43‐8.36), HPV33 (1.01, 0.49‐3.31), HPV52 (0.99, 0.76‐1.33), and HPV58 (0.97, 0.75‐1.32). The relative risk of disease progression was 1.87 (95% CI, 1.71‐2.05) for HPV16/18/31/33/35/45/52/58, but only 0.17 (95% CI, 0.14‐0.22) for HPV39/51/56/59/66/68. Human papillomavirus 16/18/31/33/45/52/58/6/11 included in a 9‐valent vaccine contributed to 89.7% (95% CI, 88.7‐90.7) of CIN2‐3/AIS and 93.8% (95% CI, 92.4‐95.3) of ICC. In conclusion, our data support the Japanese guidelines that recommend discriminating HPV16/18/31/33/35/45/52/58 genotypes for CIN management. The 9‐valent vaccine is estimated to provide over 90% protection against ICC in young Japanese women.  相似文献   
4.
This study aimed to establish the Japanese Cancer Genome Atlas (JCGA) using data from fresh frozen tumor tissues obtained from 5143 Japanese cancer patients, including those with colorectal cancer (31.6%), lung cancer (16.5%), gastric cancer (10.8%) and other cancers (41.1%). The results are part of a single‐center study called “High‐tech Omics‐based Patient Evaluation” or “Project HOPE” conducted at the Shizuoka Cancer Center, Japan. All DNA samples and most RNA samples were analyzed using whole‐exome sequencing, cancer gene panel sequencing, fusion gene panel sequencing and microarray gene expression profiling, and the results were annotated using an analysis pipeline termed “Shizuoka Multi‐omics Analysis Protocol” developed in‐house. Somatic driver alterations were identified in 72.2% of samples in 362 genes (average, 2.3 driver events per sample). Actionable information on drugs that is applicable in the current clinical setting was associated with 11.3% of samples. When including those drugs that are used for investigative purposes, actionable information was assigned to 55.0% of samples. Germline analysis revealed pathogenic mutations in hereditary cancer genes in 9.2% of samples, among which 12.2% were confirmed as pathogenic mutations by confirmatory test. Pathogenic mutations associated with non–cancerous hereditary diseases were detected in 0.4% of samples. Tumor mutation burden (TMB) analysis revealed 5.4% of samples as having the hypermutator phenotype (TMB ≥ 20). Clonal hematopoiesis was observed in 8.4% of samples. Thus, the JCGA dataset and the analytical procedures constitute a fundamental resource for genomic medicine for Japanese cancer patients.  相似文献   
5.
BackgroundFluoroquinolones are a popular alternative to trimethoprim-sulfamethoxazole for Stenotrophomonas maltophilia infections.ObjectivesTo compare the effects of fluoroquinolones and trimethoprim-sulfamethoxazole on mortality of S. maltophilia infections.Data sourcesPubMed and EMBASE.Study eligibility criteriaClinical studies reporting mortality outcomes of S. maltophilia infections.ParticipantsPatients with clinical infections caused by S. maltophilia.InterventionsFluoroquinolone monotherapy in comparison with trimethoprim-sulfamethoxazole monotherapy.MethodsSystematic review with meta-analysis technique.ResultsSeven retrospective cohort and seven case–control studies were included. Three cohort studies were designed to compare the two drugs, whereas others had other purposes. A total of 663 patients were identified, 332 of which were treated with trimethoprim-sulfamethoxazole (50.1%) and 331 with fluoroquinolones (49.9%). Three cohort studies were designed to compare the effect of the two drugs, whereas the others had other purposes. Levofloxacin was most frequently used among fluoroquinolones (187/331, 56.5%), followed by ciprofloxacin (114/331, 34.4%). The overall mortality rate was 29.6%. Using pooled ORs for the mortality of each study, fluoroquinolone treatment (OR 0.62, 95% CI 0.39–0.99) was associated with survival benefit over trimethoprim-sulfamethoxazole treatment, with low heterogeneity (I2 = 18%). Specific fluoroquinolones such as ciprofloxacin (OR 0.44, 95% CI 0.17–1.12) and levofloxacin (OR 0.78, 95% CI 0.48–1.26) did not show a significant difference in comparison with trimethoprim-sulfamethoxazole. In the sub-group analyses of adult and bacteraemic patients, significant differences in mortality were not observed between fluoroquinolones and trimethoprim-sulfamethoxazole.ConclusionsBased on a meta-analysis of non-randomized studies, fluoroquinolones demonstrated comparable effects on mortality of S. maltophilia infection to trimethoprim-sulfamethoxazole, supporting the use of fluoroquinolones in clinical S. maltophilia infections. Although the pooled analysis of overall studies favoured fluoroquinolones over trimethoprim-sulfamethoxazole, the studies included were observational, and sub-group analyses of certain fluoroquinolone agents did not show statistical differences with trimethoprim-sulfamethoxazole. Randomized clinical studies are needed to address these issues.  相似文献   
6.
A novel polyfunctional benzoxazine monomer, OP‐a , is synthesized from aniline, formaldehyde, and an oligonuclear phenolic compound (OP) with a 4,4′‐dimethylenebiphenyl group as the phenol linker. After thermal curing of OP‐a up to 240 °C, a brown‐colored, transparent polybenzoxazine ( POP‐a ) film is obtained. The mechanical and thermal properties of the POP‐a film are investigated by tensile test, dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). The POP‐a film is extremely tough compared with a typical polybenzoxazine ( PB‐a ) film. The elongation at break of the POP‐a film is 7.6%, which is surprisingly large for the highly cross‐linked thermoset. The high cross‐link density is suggested from the very high storage modulus (over 1 GPa) above the glass transition temperature (T g) observed by DMA. The T g of POP‐a is also improved significantly to T g = 223 °C, which is approximately 50 °C higher than that of PB‐a . Moreover, TGA reveals that the thermal stability of POP‐a is also enhanced.  相似文献   
7.
OBJECTIVES: This study examined toothbrush/dentifrice abrasion of a photo-activated prosthetic composite (dentin and enamel variations) for the purpose of evaluating the influence of polymerization sources on abrasive wear. METHODS: A photo-activated prosthetic composite material (Artglass) was assessed. Dentin and enamel variations were polymerized using a proprietary photo-curing unit with two xenon stroboscopic lamps (UniXS), and other enamel specimens were polymerized either with a laboratory photo-curing unit with three fluorescent tubes or with a high intensity unit with two metal halide lamps. All specimens were stored in water for 14days and subjected to toothbrush/dentifrice abrasion (350g vertical load) using an abrasive slurry (Colgate Fluoriguard) and a toothbrush (Oral-B 40). The amount of vertical loss and the surface roughness of the specimens after 20,000 strokes were determined by profilometer. Average values of groups of five specimens were compared using analysis of variance (ANOVA) and Sheffe's S intervals (p<0.05). RESULTS: When polymerizing with the proprietary unit, the abrasion and surface roughness of the enamel material required respective means of 34.08microm (+/-3.66) and 1.00microm (+/-0.08), and the those of the dentin material required means of 42.02microm (+/-5.62) and 1.23microm (+/-0.20). Both abrasion and surface roughness after toothbrushing of the enamel material were significantly smaller than were those of the dentin material. The abrasion of specimens polymerized with the metal halide unit required a mean of 23.89microm (+/-6.17) and demonstrated minimal wear. CONCLUSIONS: The use of a high intensity metal halide photo-curing unit effectively enhanced the abrasion resistance of the composite. Surfaces of restorations should be covered with the enamel material in order to achieve smoothness and wear resistance.  相似文献   
8.
This study was designed to investigate the relationship between the etched depth, penetration of sealants and marginal seal. Sixty unerupted lower first premolars extracted from patients for orthodontic reasons were thoroughly cleaned and stored in an antiseptic Ringer's solution at 4 degrees C. A "window" on the occlusal of 15 of the premolars, including both mesial and distal pits, was developed by painting nail varnish around the border of the occlusal surfaces. Etching was then done with 35% phosphoric acid for 60 seconds to all 60 premolars. Five of the "window" teeth were evaluated by microradiography to determine the etched depth of the superficial and subsurface enamel. Five were prepared for SEM analysis to observe the change of the superficial etched enamel surface. Another five "window" teeth were embedded in epoxy resin and sectioned parallel to the long axis of the tooth through the fissures in order to observe the subsurface depth of the etch by SEM analysis. The other 45 teeth were divided into three groups of 15 teeth each. Fissures of each group of teeth were sealed using Prisma-Shield (LD Caulk), Concise White Sealant (3M Dental Products) or Teethmate A (Kuraray) sealants and stored in water (37 degrees C) for 24 hours. They were then sectioned and demineralized before being examined by a scanning electron microscope. Photographs of secondary electron image (SEI) were done to gradate the resin-infiltrated enamel and resin tags for these sealants. After SEM observation, the 15 samples of each applied sealant were polished to a high gloss again and placed in a silver nitrate solution for 24 hours before being examined under the SEM equipped with a back-scatter electron detector. Data were then analyzed using the Welch and Student t-tests. Results showed that fissured enamel of unerupted human lower first premolars became porous after etching with 35% phosphoric acid. The low viscosity sealant Teethmate A (approximately 260 mPa.s), penetrated fully and formed a resin-infiltrated layer in enamel beyond the etched depth. However, the high viscosity sealants (Prisma-Shield and Concise White Sealant) did not penetrate enough to ensure that the acid-etched enamel was infiltrated sufficiently by the sealant to insure good marginal seals.  相似文献   
9.
10.
This study determined the hardness, solubility and curing depth of a new photo-activated composite polymerized with three different laboratory photo-curing units for the purpose of evaluating the post-curing properties of the material. A new photo-activated composite material for both direct and indirect applications (DiamondCrown) was polymerized with three photo-curing units equipped with the following light sources: (i) two halogen lamps (DiamondLite-VL. Halogen Light Curing Booth); (ii) two metal halide lamps (Hyper LII) and (iii) two xenon stroboscopic tubes (UniXS II). Knoop hardness, water solubility and curing depth were determined for groups of five specimens according to standardized testing methods. All data were compared using analysis of variance (anova) and Scheffe's S intervals (P < 0.05). The Knoop hardness number (KHN) generated with the metal halide unit (63.3 +/- 2.4 KHN) was statistically (P < 0.05) greater than those produced by the other two curing units. Water solubility values for both the halogen unit (2.5 +/- 0.5 microg mm(-3)) and the metal halide unit (2.5 +/- 0.5 microg mm(-3)) were significantly (P < 0.05) lower than for the xenon unit (3.8 +/- 0.5 microg mm(-3)). Of the three photo-curing units, the metal halide curing-unit consistently exhibited the greatest depth of cure. The composite material appears to be reliable, although its post-curing properties were found to be influenced by the type of curing unit.  相似文献   
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