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Sound exposure data are central for any intervention study. In the case of utilitarian mobility, where studies cannot be conducted in controlled environments, exposure data are commonly self-reported. For short-term intervention studies, wearable devices with location sensors are increasingly employed. We aimed to combine self-reported and technically sensed mobility data, in order to provide more accurate and reliable exposure data for GISMO, a long-term intervention study. Through spatio-temporal data matching procedures, we are able to determine the amount of mobility for all modes at the best possible accuracy level. Self-reported data deviate ±10% from the corrected reference. Derived modal split statistics prove high compliance to the respective recommendations for the control group (CG) and the two intervention groups (IG-PT, IG-C). About 73.7% of total mileage was travelled by car in CG. This share was 10.3% (IG-PT) and 9.7% (IG-C), respectively, in the intervention groups. Commuting distances were comparable in CG and IG, but annual mean travel times differ between  = 8,458 min (σ = 6,427 min) for IG-PT,  = 8,444 min (σ = 5,961 min) for IG-C, and  = 5,223 min (σ = 5,463 min) for CG. Seasonal variabilities of modal split statistics were observable. However, in IG-PT and IG-C no shift toward the car occurred during winter months. Although no perfect single-method solution for acquiring exposure data in mobility-related, naturalistic intervention studies exists, we achieved substantially improved results by combining two data sources, based on spatio-temporal matching procedures.  相似文献   
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OBJECTIVES: The purpose of this study was to measure and analyze the mechanical properties of several composite materials designed for dental restoration. METHODS: The materials were composed of a visible light-curing monomer mixture (either Bis-GMA+TEGDMA or Bis-GMA+HEMA) as a matrix and hydroxyapatite (either microscopic or nanoscopic particles) as a reinforcing filler. The surface of the hydroxyapatite particles was modified by using a coupling agent (citric, malic, acrylic or methacrylic acid). Five specimens of 14 different composites were prepared for each mechanical test: flexural strength, Young's modulus and Vickers hardness. Mean values and standard deviations were calculated, and ANOVA and Student Newman Keuls multiple comparison tests were applied (P < 0.05). RESULTS: The addition of 50-60 wt% of hydroxyapatite particles to the unfilled monomer mixtures led to the increase of both Young's modulus and surface hardness of the material, while the flexural strength decreased. In general, when microscopic instead of nanoscopic hydroxyapatite was used as a reinforcing filler, mechanical properties were favored. The mechanical properties were also improved by adding citric, acrylic or methacrylic acid as a coupling agent. CONCLUSIONS: An adequate surface modification of the hydroxyapatite particles conferred enhanced mechanical properties to the final dental composite. Microscopic-hydroxyapatite particles are preferred to nanoscopic ones.  相似文献   
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The mononuclear cells separated from human blood by Ficoll-Hypaque centrifugation contained and released sialyltransferase, galactosyltransferase, and fucosyltransferase. Granulocytes contained and released lesser amounts of glycosyltransferases, whereas platelets released more fucosyltransferase than sialyltransferase or galactosyltransferase. When mononuclear cells were incubated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), the release of these three glycosyltransferases increased two- to six-fold, and cell suspension glycosyltransferase activities decreased 10-50%. Mononuclear cells were fractionated into lymphocytes and monocytes using baby hamster kidney cells microexudate-coated flasks. TPA stimulated the release of glycosyltransferases from lymphocytes but not from monocytes. The release of glycosyltransferases by TPA-treated mononuclear cells was not further stimulated by reincubation with TPA and was not affected by puromycin, cAMP, or cGMP. Concanavalin A, a mitogenic stimulator of lymphocytes, also stimulated the release of glycosyltransferases from mononuclear cells, but to a lesser extent. TPA did not stimulate the release of 5′-nucleotidase or decrease its activity on the cell pellet. Triton X-100 (0.2%) stimulated the release of glycosyltransferases to the same extent as TPA, but also caused the release of 5′-nucleotidase. [3H]TPA bound specifically and reversibly to mononuclear cells. The possible relationship between glycosyltransferase release and TPA effect on the plasma membrane is discussed.  相似文献   
7.
Mesenchymal stem cells (MSCs) of mammals have been isolated from many tissues and are characterized by their aptitude to differentiate into bone, cartilage, and fat. Differentiation into cells of other lineages like skeletal muscle, tendon/ligament, nervous tissue, and epithelium has been attained with MSCs derived from some tissues. Whether such abilities are shared by MSCs of all tissues is unknown. We therefore compared for three human donors the myogenic properties of MSCs from adipose tissue (AT), bone marrow (BM), and synovial membrane (SM). Our data show that human MSCs derived from the three tissues differ in phenotype, proliferation capacity, and differentiation potential. The division rate of AT-derived MSCs (AT-MSCs) was distinctly higher than that of MSCs from the other two tissue sources. In addition, clear donor-specific differences in the long-term maintenance of MSC proliferation ability were observed. Although similar in their in vitro fusogenic capacity with murine myoblasts, MSCs of the three sources contributed to a different extent to skeletal muscle regeneration in vivo. Transplanting human AT-, BM-, or SM-MSCs previously transduced with a lentiviral vector encoding β-galactosidase into cardiotoxin-damaged tibialis anterior muscles (TAMs) of immunodeficient mice revealed that at 30 days after treatment the frequency of hybrid myofibers was highest in the TAMs treated with AT-MSCs. Our finding of human-specific β-spectrin and dystrophin in hybrid myofibers containing human nuclei argues for myogenic programming of MSCs in regenerating murine skeletal muscle. For the further development of MSC-based treatments of myopathies, AT-MSCs appear to be the best choice in view of their efficient contribution to myoregeneration, their high ex vivo expansion potential, and because their harvesting is less demanding than that of BM- or SM-MSCs.  相似文献   
8.

Background

The aim of the present study was to evaluate whether serum C-reactive protein (CRP) is a useful predictor of early post-operative complications, particularly of intestinal leaks after laparoscopic Roux-en-Y gastric bypass (LRYGB) surgery.

Methods

The present study was a retrospective analysis of a prospectively maintained database with 809 patients who underwent LRYGB from 2002 until 2011. For 410 of these patients, at least one CRP measurement within the first seven post-operative days was available. The diagnostic value was determined by the area under the curve (AUC) of the receiver operating characteristic (ROC) curve.

Results

Forty-nine of 410 patients (12.0?%; 95?% confidence intervals [95?% CI], 9.2?C15.5?%) developed surgery-related complications. Leaks occurred in 17 patients (4.1?%; 95?% CI, 2.6?C6.5?%) at a median of 5?days after surgery. CRP levels 2?days after surgery showed the highest diagnostic value for post-operative complications (AUC, 0.74; 95?% CI, 0.60?C0.89). Sensitivity was 0.53 (95?% CI, 0.31?C0.74) and specificity was 0.91 (95?% CI, 0.79?C0.96) on day 2 (cutoff level, 229?mg/l). The sensitivity for intestinal leaks was 1.00 (95?% CI, 0.51?C1.00).

Conclusion

CRP on post-operative day 2 is a valuable predictor of post-operative complications, in particular intestinal leaks. Radiological imaging studies for intestinal leaks could be restricted to patients with CRP values exceeding 229?mg/l.  相似文献   
9.
ABSTRACT

Background: Logging is recognized as one of the most dangerous industries in the United States (US), ranking among those with the highest occupational injury and fatality rates. Although logging operations in the Southeastern US have lower rates of injuries and fatalities compared to other regions of the US, due in part to the use of large machinery to fell timber as opposed to chainsaw felling, safety hazards continue to persist. The hazards present in the logging cut sites in which loggers operate may result in worker injury, illness, or fatality. Our objective was to develop, deliver, and evaluate a safety management and leadership training among logging contractors and supervisors using mobile tablets as a personal learning environment.

Methods: A safety leadership and management training vignette was developed based on previously collected focus group needs assessment data. A non-random sample of 31 male logging supervisors received the safety leadership and management training on a mobile tablet. Kirkpatrick Levels 1, 2, and 3 training effectiveness evaluations were performed.

Results: A statistically significant large effect size suggests safety knowledge was gained among training participants when comparing post-test scores to pre-test scores (Level-2). Participants rated their training experience favorably (Level-1), and applied knowledge gained from the training throughout their weekly work activities three months after training (Level-3).

Conclusion: Our findings suggest the utilization of mobile learning techniques can be an effective means to deliver safety management and leadership training content to logging contractors and supervisors. Future trainings should be linguistically and literacy-level appropriate, as well as comprehensive in nature, including meaningful and relevant content. Our observations support the use of mobile devices as just one component of a more comprehensive health and safety management program for workers in the logging industry.  相似文献   
10.
Infant regurgitation is common during infancy and can cause substantial parental distress. Regurgitation can lead to parental perception that their infant is in pain. Parents often present in general practitioner surgeries, community baby clinics and accident and emergency departments which can lead to financial burden on parents and the health care system. Probiotics are increasingly reported to have therapeutic effects for preventing and treating infant regurgitation. The objective of this systematic review and meta-analysis was to evaluate the efficacy of probiotic supplementation for the prevention and treatment of infant regurgitation. Literature searches were conducted using MEDLINE, CINAHL, and the Cochrane Central Register of Controlled trials. Only randomised controlled trials (RCTs) were included. A meta-analysis was performed using the Cochrane Collaboration methodology where possible. Six RCTs examined the prevention or treatment with probiotics on infant regurgitation. A meta-analysis of three studies showed a statistically significant reduction in regurgitation episodes for the probiotic group compared to the placebo group (mean difference [MD]: ?1.79 episodes/day: 95% confidence interval [CI]: ?3.30 to ?0.27, N = 560), but there was high heterogeneity (96%). Meta-analysis of two studies found a statistically significant increased number of stools per day in the probiotic group compared to the placebo group at 1 month of age (MD: 1.36, 95% CI: 0.99 to 1.73, N = 488), with moderate heterogeneity (69%). Meta-analysis of two studies showed no statistical difference in body weight between the two groups (MD: ?91.88 g, 95% CI: 258.40–74.63: I2 = 23%, N = 112) with minimal heterogeneity 23%. Probiotic therapy appears promising for infant regurgitation with some evidence of benefit, but most studies are small and there was relatively high heterogeneity. The use of probiotics could potentially be a noninvasive, safe, cost effective, and preventative positive health strategy for both women and their babies. Further robust, well controlled RCTs examining the effect of probiotics for infant regurgitation are warranted.  相似文献   
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