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The purpose of our study was to evaluate the use of bleeding-avoidance strategies (BAS) and risk-adjusted bleeding over time in patients ≥80 years of age undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction. We analyzed data from the CathPCI Registry from July 1, 2006 through June 30, 2009. Patients were included if they were ≥80 years old, presented with ST-segment elevation myocardial infarction, and underwent primary PCI. We evaluated trends in use of BAS (direct thrombin inhibitors, vascular closure devices, and radial access) and risk-adjusted bleeding over time. Of 10,469 patients ≥80 years old undergoing primary PCI, 1,002, (9.6%) developed a bleeding complication. Use of direct thrombin inhibitors and vascular closure devices increased over time (12.8% to 24.9% and 29.2% to 32.7%, p <0.01 and <0.05 for trends, respectively). Radial access was extremely uncommon (<1%) and did not change over the course of the study. In multivariable analyses, use of BAS was associated with lower bleeding. However, over the course of the study period, overall risk-adjusted bleeding did not decrease significantly (9.9% to 9.4%, p = 0.14 for trend). In conclusion, patients ≥80 years old undergoing primary PCI are at high risk of bleeding, and despite significant increases in use of BAS, the overall rate of bleeding complications remains high.  相似文献   
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The sural nerve is at risk of iatrogenic injury even during minimally invasive operative procedures to repair the calcaneal (Achilles) tendon. Through 107 cadaveric leg dissections, the data derived from the present study was used to develop a regression equation that will enable surgeons to estimate the intersection point at which the sural nerve crosses the lateral border of the Achilles tendon, an important surgical landmark. In most cases, the sural nerve crossed the lateral border of the Achilles tendon 8 to 10 cm proximal to the superior border of the calcaneal tuberosity. By simply measuring the leg length of the patient (from the base of the heel to the flexor crease of the popliteal fossa), surgeons can approximate the location of this intersection point with an interval length of 0.68 to 1.80 cm, with 90% confidence, or 0.82 to 2.15 cm, with 95% confidence. For example, for a patient with a lower leg length of 47.0 cm, the mean measurement in the present study, a surgeon can be 90% confident that the sural nerve will cross the lateral border of the Achilles tendon 8.28 to 8.96 cm (interval width of 0.68 cm) proximal to the calcaneal tuberosity. Currently, ultrasound and clinical techniques have been implemented to approximate the location of the sural nerve. The results of the present study offer surgeons another method, that is less intensive, to locate reliably and subsequently avoid damage to the sural nerve during calcaneal (Achilles) tendon repair and other procedures of the posterolateral leg and ankle.  相似文献   
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We describe a rapid two-temperature PCR protocol for amplification of genomic DNA applied to the region of the most common mutation (delta F508) of the cystic fibrosis gene. Amplification products are detected as homo- or heteroduplexes on polyacrylamide gels as previously described. Data using two-temperature PCR show complete concordance with allele-specific hybridization after classical three-temperature PCR in 105 normal, carrier and affected individuals. Clinical application is demonstrated in a family which was uninformative by traditional RFLP linkage analysis. Two-temperature PCR may offer advantages of speed and specificity over three-temperature PCR in many clinical and research applications.  相似文献   
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DATA SOURCE: Studies were identified using the Cochrane trials registers of the Oral Health Group and of the Pain, Palliative and Supportive Care Group, along with the Cochrane Central Register of Controlled Trials, Medline, Embase and the Current Controlled Trials Register. Handsearching included several dental journals as well as the bibliographies of relevant clinical trials and review articles for studies outside the journals searched by hand. Authors of the randomised controlled trials (RCT) identified and manufacturers of analgesic pharmaceuticals were contacted in an attempt to identify unpublished or ongoing RCT. No language restriction was applied. STUDY SELECTION: Randomised, parallel-group, placebo-controlled, double-blind clinical trials of paracetamol (acetaminophen) for acute pain following third molar surgery were included. DATA EXTRACTION AND SYNTHESIS: All trials identified were scanned independently and in duplicate by two review authors. Any disagreements were resolved by discussion or, if necessary, a third review author was consulted. The proportion of patients who recorded at least 50% pain relief was calculated for both paracetamol and placebo. The number of patients experiencing adverse events, and/ or the total number of adverse events reported were analysed. RESULTS: Twenty-one trials met the inclusion criteria. A total of 2048 people were initially enrolled in the trials (1148 took paracetamol and 892 the placebo) and of these 1968 (96%) were included in the meta-analysis (1133 took paracetamol, and 835 the placebo). Paracetamol provided a statistically significant benefit when compared with placebo for pain relief and for pain intensity at both 4 and 6 h. Most studies were found to have moderate risk of bias, with poorly reported allocation concealment being the main problem. The risk ratio for pain relief at 4 h was 2.85 (95% confidence interval, 1.89-4.29), and at 6 h was 3.32 (95% confidence interval, 1.88-5.87). A statistically significant benefit was also found between doses of <1000 mg and of 1000 mg, the higher dose giving greater benefit for pain relief and intensity at both timepoints. There was no statistically significant difference between the number of patients who reported adverse events: this was 19% in the paracetamol group and 16% in the placebo group. CONCLUSIONS: Paracetamol is an effective drug to use for postoperative pain following oral surgery, and the reporting of adverse events shows it to be a safe drug: the number-needed-to-treat (NNT) to benefit is three for 1000 mg of paracetamol at 6 h and the NNT to harm is 33. It is most effective at a 1000 mg dose, and can be taken at 6-hourly intervals without compromising safety. It could be considered more readily by dentist and patients both as a first-choice analgesic, or to be taken alternately with other analgesics such as nonsteroidal anti-inflammatory drugs.  相似文献   
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Introduction

An ideal ligature should tighten readily and remain tight. Ligature failure can be a critical complication of invasive procedures in human and veterinary surgical practice. Previous studies have tested various knots but not the constrictor knot.

Methods

A new test bench was employed to compare six ligatures using four suture materials. As tension in a ligature is not readily measured, the study employed a surrogate measurement: the force required to slide a ligature along a rod. Benchmark values tested each suture material wrapped around the rod to establish the ratio between this force and the ligature tension for each material. Each ligature was tested first during tightening and then again afterwards. The benchmark ratios were employed to calculate the tensions to evaluate which ligature and which suture material retained tension best.

Results

The model provided consistent linear relationships between the tension in the suture and the force required to pull the ligature along the rod. The constrictor knot retained tension in the ligature best (55–107% better than the next best ligature). Among the suture materials, polydioxanone had the greatest ability to retain the tension in a ligature and polyglactin the least.

Conclusions

The constrictor knot showed superior characteristics for use as a ligature, and should be introduced into teaching and clinical practice for human and veterinary surgery. The new test bench is recommended for future testing of ligatures as well as objective comparison of suture materials.  相似文献   
30.

Introduction

Stomas often have to be sited in emergencies by trainees who may have had little training in this. Emergency stomas and stomas where the site has not been marked preoperatively by a stoma therapist are more prone to complications. These complications may severely affect a patient’s quality of life. Advice in the literature on how to best site stomas is conflicting. We compared two easy anatomical methods of siting stomas to sites chosen by a stoma therapist and looked at how this site was affected by the patients’ body mass index (BMI).

Methods

Patients undergoing elective colorectal surgery were seen either pre or postoperatively. Each patient’s BMI was recorded and the positions of three different potential stoma positions (site G: the gold standard, marked by a stoma therapist; site S: marked using a pair of scissors against the umbilicus; site H: halfway between the umbilicus and anterior superior iliac spine) were compared.

Results

The two fixed anatomical methods described (method S and method H) both gave poor results. The most common reason for poor siting was the proximity of a skin crease. There was a statistically significant correlation between the patient’s BMI and the laterality of the gold standard site.

Conclusions

The two simple anatomical methods described here do not provide a shortcut to effective siting. A more effective method may be calculating the laterality of the site using the patient’s BMI, and then moving up/down to avoid a skin crease and improve the patient’s view for changing the bag. This deserves further study.  相似文献   
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