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41.
Background and study aimsSince the introduction of liver transplantation (LTx) in children suffering from liver failure in 1963, many centres around the world have offered this service to children that have no other alternative. The aim of this retrospective study is to analyse the results of paediatric liver transplant in Kuwait over the last decade.Patients and methodsA retrospective chart review was done involving paediatric patients during the time period of 1995–2004. The information collected included patient demographics, indications for liver transplantation, survival of both patient and allograft, and complications.ResultsA total of 16 cases were found and analysed. The mean age was 3.6 years (ranged 5 months–17 years). There were nine boys and seven girls. The most common indications for LTx were biliary atresia and metabolic liver disease. All the liver transplants were done abroad. There were totally nine deceased donor and seven living related cases. The complications were acute cellular rejection in five, hypertension in two, biliary complications in four, cytomegalovirus (CMV) infection in three and post lymphoproliferative disease in two cases. All but one patient are presently alive.ConclusionThe above information demonstrates that LTx in Kuwati children is safe and improves the quality of life for those that would otherwise have no other alternative.  相似文献   
42.
Objective  To evaluate the risk of vascular injury during transobturator approach of cystocele repair.
Design  Dissection of the obturator area by perineal approach was performed after placement of mesh needles used for cystocele mesh repair.
Setting  Surgery school of Paris.
Population or sample  Twenty obturator regions in ten fresh female cadavers.
Methods  Transperineal dissection of the obturator area was conducted in ten fresh female anatomic subjects after inserting anterior Prolift® needles.
Main outcome measures  The vascular anatomy of the obturator region was mapped. Distances between needles and vascular structures of the obturator area were measured three times and averaged for each side.
Results  The anterior cannula-equipped needle perforated the gracilis and the adductor brevis muscles. The mean (SD) distance to the anterior obturator vessels was 21.2 (1.6) mm on the right side and 20.4 (1.5) mm on the left. The posterior needle perforated the adductor magnus. Its distance to the posterior division of the obturator vessels was 1.8 (1.0) mm on the right side and 1.1 (0.9) mm on the left.
Conclusions  During mesh cystocele repair by transobturator approach, the posterior obturator vessels division seems at risk of injury during the posterior needle insertion.  相似文献   
43.
BACKGROUND: In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF). METHODS: We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months. RESULTS: Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53). CONCLUSIONS: In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.  相似文献   
44.
Positively selected CD34(+) hematopoietic stem cells from unrelated donors (UD-HSCT) have been successfully transplanted, but little is known about immune reconstitution in this setting. Here we report a prospective comparison of immune reconstitution in recipients of UD-HSCT and of unmanipulated bone marrow from matched sibling donors (MSD-BMT). T-cell reconstitution occurred more than 100 days later in the UD-HSCT than in the MSD-BMT group. The first T cells after UD-HSCT were almost exclusively CD45RO(+) HLA-DR(+), whereas early-emerging T cells after MSD-BMT more frequently expressed CD62L, CD28, and CD25. In both groups, numbers of CD45RA(+) naive T cells increased after 180 days. After UD-HSCT, the T-cell-receptor (TCR)-repertoire was severely skewed and showed significantly reduced diversity during the first year, but only minor abnormalities were seen after MSD-BMT. TCR-diversity increased simultaneously with the number of naive T cells. In both groups, we observed transient expansions of gammadelta T cells. B cells were reconstituted more rapidly in UD-HSCT than in MSD-BMT recipients, whereas the rapidity of NK-cell reconstitution was similar in the two groups. In summary, T-cell reconstitution was slower after UD-HSCT than after MSD-BMT because of the delayed recovery of early memory-type T cells with reduced TCR-diversity, whereas naive T-, NK-, and B cells were reconstituted similarly in the two groups.  相似文献   
45.
46.
We describe neonatal spontaneous pneumothorax associated with transient tachypnea of the newborn in siblings of two families. Familial spontaneous pneumothorax is extremely rare in neonates. Was our observation just an incidental finding, or is there a familial predisposition to spontaneous pneumothorax? Pediatr Pulmonol. 2003; 36:69–72. © 2003 Wiley‐Liss, Inc.  相似文献   
47.
Background and aims Despite improved techniques, the determination of tumor origin in poorly differentiated adenocarcinomas still remains a challenge for the pathologist. Here we report the use of protein profiling combined with principal component analysis to improve diagnostic decision-making in tumor samples, in which standard pathologic investigations cannot present reliable results. Materials and methods A poorly differentiated adenocarcinoma of unknown origin located in the pelvis, infiltrating the sigmoid colon as well as the ovary, served as a model to evaluate our proteomic approach. Firstly, we characterized the protein expression profiles from eight advanced colon and seven ovarian adenocarcinomas using two-dimensional gel electrophoresis (2-DE). Qualitative and quantitative patterns were recorded and compared to the tumor of unknown origin. Based on these protein profiles, match sets from the different tumors were created. Finally, a multivariate principal component analysis was applied to the entire 2-DE data to disclose differences in protein patterns between the different tumors. Results Over 89% of the unknown tumor sample spots could be matched with the colon standard gel, whereas only 63% of the spots could be matched with the ovarian standard. In addition, principal component analysis impressively displayed the clustering of the unknown case within the colon cancer samples, whereas this case did not cluster at all within the group of ovarian adenocarcinomas. Conclusion These results show that 2-DE protein expression profiling combined with principal component analysis is a sensitive method for diagnosing undifferentiated adenocarcinomas of unknown origin. The described approach can contribute greatly to diagnostic decision-making and, with further technical improvements and a higher throughput, become a powerful tool in the armentarium of the pathologist. UJ Roblick and FG Bader contributed equally to this work and should be recognized as first authors.  相似文献   
48.
Repairing large segmental defects in long bones caused by fracture, tumour or infection is still a challenging problem in orthopaedic surgery. Artificial materials, i.e. titanium and its alloys performed well in clinical applications, are plenary available, and can be manufactured in a wide range of scaffold designs. Although the mechanical properties are determined, studies about the biomechanical behaviour under physiological loading conditions are rare. The goal of our numerical study was to determine the suitability of open-porous titanium scaffolds to act as bone scaffolds. Hence, the mechanical stability of fourteen different scaffold designs was characterized under both axial compression and biomechanical loading within a large segmental distal femoral defect of 30 mm. This defect was stabilized with an osteosynthesis plate and physiological hip reaction forces as well as additional muscle forces were implemented to the femoral bone. Material properties of titanium scaffolds were evaluated from experimental testing. Scaffold porosity was varied between 64 and 80%. Furthermore, the amount of material was reduced up to 50%. Uniaxial compression testing revealed a structural modulus for the scaffolds between 3.5 GPa and 19.1 GPa depending on porosity and material consumption. The biomechanical testing showed defect gap alterations between 0.03 mm and 0.22 mm for the applied scaffolds and 0.09 mm for the intact bone. Our results revealed that minimizing the amount of material of the inner core has a smaller influence than increasing the porosity when the scaffolds are loaded under biomechanical loading. Furthermore, an advanced scaffold design was found acting similar as the intact bone.  相似文献   
49.
In this study, we use classical applied mathematical modelling to employ the 6–12 Lennard-Jones potential function along with the continuous approximation to investigate the interaction energies between a double-stranded deoxyribonucleic acid (dsDNA) molecule and two-dimensional nanomaterials, namely graphene (GRA), hexagonal boron nitride (h-BN), molybdenum disulphide (MoS2), and tungsten disulphide (WS2). Assuming that the dsDNA molecule has a perpendicular distance Δ above the nano-sheet surface, we calculated the molecular interaction energy and determined the relation between the location of the minimum energy and Δ. We also investigated the interaction of a dsDNA molecule with the surface of each nano-sheet in the presence of a circular hole simulating a nanopore. The radius of the nanopore that results in the minimum energy was determined. Our results show that the adsorption energies of the dsDNA molecule with GRA, h-BN, MoS2, and WS2 nano-sheets corresponding to the perpendicular distance Δ = 20 Å are approximately 70, 82, 28, and 26 (kcal mol−1), respectively, and we observed that the dsDNA molecule moves through nanopores of radii greater than 12.2 Å.

Using classical applied mathematical modelling to employ the 6–12 Lennard-Jones potential function along with the continuous approximation to investigate the interaction energy between dsDNA and 2D-nanomaterials, namely GRA, h-BN, MoS2 and WS2 sheets.  相似文献   
50.
BackgroundThe coronavirus diseases of 2019 (COVID-19) pandemic was classified as one of the worst pandemics in the 21st century. Its rapid transmission, unpredicted mortality rate, and the uncertainty surrounding its transmission method have evoked additional fear and anxiety. Nonetheless, to the best of our knowledge, no prior study has explored PTSD prevalence three months after the start of the quarantine procedures in Saudi Arabia nor has examined PTSD prevalence by three different methods.ObjectiveThis observational cross-sectional study aimed to identify the prevalence, severity, and influencing factors of PTSD in different regions of Saudi Arabia three months after the onset of the quarantine procedures related to the COVID-19 pandemic.MethodsThrough the month of June 2020, 1374 people (49.05% men and 50.95% women) completed a 35-item, 10-minute online. The prevalence of PTSD was measured using PCL-S (specific for COVID-19) that assesses the 17 symptoms of PTSD. Resilience was measured using 2-items Arabic version of the Connor-Davidson Resilience Scale 2 (CD-RISC 2).ResultsWe calculated the prevalence by three methods, namely, PTSD cut-off score, criteria, and combined, and the prevalence was 22.63%, 24.8%, and 19.6%, respectively. Female participants showed higher prevalence than male. As well, participants who were either tested positive or suspected of having been infected with COVID-19 showed higher PTSD prevalence. Higher resilience was associated with lower PTSD prevalence.ConclusionsThis was the first study to report PTSD prevalence by three differential methods three months after the onset of the quarantine procedures related to the COVID-19 pandemic in Saudi Arabia. We observed a significant impact of the COVID-19 pandemic in the Saudi population; therefore, great attention should be performed in implementing new procedures that deal with the highlighted risk factors, especially in vulnerable groups, to overcome the psychological impact of the COVID-19 pandemic.  相似文献   
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