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81.
BACKGROUND: The aim of the present investigation is to compare rates, types, causes, and timing of infectious death in incident peritoneal dialysis (PD) and hemodialysis (HD) patients in Australia and New Zealand. STUDY DESIGN: Observational cohort study using the Australian and New Zealand Dialysis and Transplant Registry data. SETTING & PARTICIPANTS: The study included all patients starting dialysis therapy between April 1, 1995, and December 31, 2005. PREDICTOR: Dialysis modality. OUTCOMES & MEASUREMENTS: Rates of and time to infectious death were compared by using Poisson regression, Kaplan-Meier, and competing risks multivariate Cox proportional hazards model analyses. RESULTS: 21,935 patients started dialysis therapy (first treatment PD, n = 6,020; HD, n = 15,915) during the study period, and 1,163 patients (5.1%) died of infectious causes (PD, 529 patients; 7.6% versus HD, 634 patients; 4.2%). Incidence rates of infectious mortality in PD and HD patients were 2.8 and 1.7/100 patient-years, respectively (incidence rate ratio PD versus HD, 1.66; 95% confidence interval [CI], 1.47 to 1.86). After performing competing risks multivariate Cox analyses allowing for an interaction between time on study and modality because of identified nonproportionality of hazards, PD consistently was associated with increased hazard of death from infection compared with HD after 6 months of treatment (<6 months hazard ratio [HR], 1.08; 95% CI, 0.76 to 1.54; 6 months to 2 years HR, 1.31; 95% CI, 1.09 to 1.59; 2 to 6 years HR, 1.51; 95% CI, 1.26 to 1.80; >6 years HR, 2.76; 95% CI, 1.76 to 4.33). This increased risk of infectious death in PD patients was largely accounted for by an increased risk of death caused by bacterial or fungal peritonitis. LIMITATIONS: Patients were not randomly assigned to their initial dialysis modality. Residual confounding and coding bias could not be excluded. CONCLUSIONS: Dialysis modality selection significantly influences risks, types, causes, and timing of fatal infections experienced by patients with end-stage kidney disease in Australia and New Zealand.  相似文献   
82.
A technique which combines the use of rapid maxillary expansion and fixed appliance in growing patients, is presented. The treatment in three patients with Class II division 1 malocclusion and different skeletal patterns is described, and relative advantages highlighted.  相似文献   
83.
FG K?ln 《MedR Medizinrecht》2008,26(5):320-322
Abstrakt  Bedient sich ein Arzt nicht nur vorübergehend der Mithilfe eines Berufskollegen, so erzielt er Einkünfte aus Gewerbebetrieb, wenn er nicht eigenverantwortlich dessen T?tigkeiten überwacht und wenn der Berufskollege auch nicht als Mitunternehmer t?tig ist.  相似文献   
84.
1病例报告女,26岁.因孕5 mo余,右腰腹部间断性疼痛3 d伴高烧,于2004-05-27急诊入本院泌尿外科.患者疼痛难忍,向右下腹放射,间歇性,无恶心呕吐,无尿急、尿频、尿痛,伴发热,体温最高可达40℃,既往无泌尿系患病史.查体: T 40℃,P 110次/min,BP 16/10 kPa,R 21次/min.痛苦面容,心肺正常,右肾区及右输尿管走行区扣击痛.  相似文献   
85.
Orthodontic treatment in a young patient with Beckwith-Wiedeman Syndrome (BWS) is reported and a multidisciplinary approach to the management of this syndrome is reviewed. The patient presented with a tendency to Class III malocclusion, an open-bite and a slight macroglossia, which was treated at an early age by glossotomy. It was decided to monitor growth without treatment and to wait for the best time to begin therapy. It was based only on functional rehabilitation, without any fixed appliances, in which optimum intercuspation of the teeth and the skeletal Class I relationship was achieved and maintained after the retention period of three years. In conclusion the treatment of BWS patients requires a multidisciplinary approach that includes orthodontics, orthopaedics and surgical intervention. It is also necessary to underline the significance of diagnosis at an early age and timely treatment to reduce the development of dento-skeletal alterations.  相似文献   
86.
Cytochrome P4501B1 (CYP1B1) is the most recently identified member of the dioxin-inducible CYP1 family. CYP1B1 is constitutively expressed in most human tissues, including colon and breast, and can activate numerous chemically diverse carcinogens. We evaluated the metabolism of the dietary heterocyclic amine carcinogen 2-amino-1-methyl-6- phenylimidazo[4,5-b]pyridine (PhIP) by microsomes from yeast expressing the human CYP1B1 protein. PhIP metabolites were analysed by HPLC with fluorescence and absorbance detection. We found that human CYP1B1 metabolizes PhIP to three products: N2-OH-PhIP, a mutagenic activation product; 4'-OH-PhIP, a detoxification product; and 2-OH-PhIP, the mutagenic potential of which is unknown. Metabolite identity was confirmed by co-elution with authentic standards and synchronous fluorescence spectroscopy. The identity of the 2-OH-PhIP standard was additionally confirmed by mass spectrometry. Kinetic studies of the formation of N2-OH-PhIP, 4'-OH-PhIP and 2-OH-PhIP by CYP1B1 indicated apparent Km values of 5.7 +/- 1.3, 2.2 +/- 0.5 and 1.3 +/- 0.2 microM, respectively. Apparent turnover rates were 0.40 +/- 0.03, 0.93 +/- 0.02 and 0.04 +/- 0.00 nmol product/min nmol P450, respectively. At saturating levels of substrate, CYP1B1-mediated formation of the non- mutagenic metabolite 4'-OH-PhIP was favored two-fold over that of the mutagenic metabolite, N2-OH-PhIP and >10-fold over that of 2-OH-PhIP. The formation of N2-OH-PhIP, a potent mutagen implicated in the etiology of human colon and breast cancer, indicates that CYP1B1 may play an important role in PhIP-mediated carcinogenesis.   相似文献   
87.
High-mobility group (HMG) proteins are nonhistone nuclear proteins that play an important role in the regulation of chromatin structure and function. HMGI-C and HMGI(Y) are members of the HMGI family of HMG proteins, and their expression in adult tissues generally correlates with malignant tumor phenotypes. However, HMGI-C and HMGI(Y) dysregulation as a result of specific rearrangements involving 12q15 and 6p21, the respective chromosomal sites in which the HMGI-C and HMGI(Y) genes are located, is also identified in a variety of common benign mesenchymal tumors, such as lipomas and uterine leiomyomata. The general prevalence of HMGI-C and HMGI(Y) protein expression and its correlation with chromosomal alterations in these benign tumors are unknown. We analyzed 95 human tumors (20 lipomas, 21 pulmonary chondroid hamartomas, 26 uterine leiomyomata, and 28 endometrial polyps) representing a selection of the benign lesions in which karyotypic alterations involving the chromosomal regions 12q15 and 6p21 are frequently detected. All cases were successfully karyotyped and some of them analyzed by fluorescent in situ hybridization with probes spanning the HMGI-C and HMGI(Y) genes. The results of this study demonstrate that expression of HMGI-C or HMGI(Y) is a common occurrence in lipomas, pulmonary chondroid hamartomas, leiomyomata, and endometrial polyps; that it correlates with 12q15 and 6p21 chromosomal alterations (p < 0.001); and that it is compatible with rearrangement of the HMGI-C and HMGI(Y) genes. The expression pattern and cellular localization of the immunoreactivity support the view that in biphasic lesions composed of a mixture of both stromal and epithelial cells, such as pulmonary chondroid hamartoma and endometrial polyps, the mesenchymal component is the site of the HMGI genetic alterations.  相似文献   
88.
MR procedures and biomedical implants, materials, and devices: 1993 update   总被引:3,自引:0,他引:3  
Shellock  FG; Morisoli  S; Kanal  E 《Radiology》1993,189(2):587
  相似文献   
89.
Orthodontic space closure in the mandibular arch by protraction of the mandibular second molars, after the extraction of first molars, may sometimes result in loss of incisor anchorage when using conventional orthodontic procedures. The introduction of miniscrews for immediate loading as orthodontic anchorage, has enlarged treatment possibilities. The authors illustrate their clinical experience in an adult patient treated with the extraction of mandibular first molars and the protraction of second and third molars into the extraction sites. Anchorage control was achieved with the surgical insertion of titanium miniscrews for immediate loading in the cortical bone distal to second bicuspids. Space closure was achieved by means of sliding mechanics according to Bidimensional Technique. The position of lower incisors was maintained preventing any detrimental facial effect.  相似文献   
90.
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