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222.
This study investigated the effects of training with voluntary hypoventilation (VH) at low pulmonary volumes. Two groups of moderately trained runners, one using hypoventilation (HYPO, n=7) and one control group (CONT, n=8), were constituted. The training consisted in performing 12 sessions of 55 min within 4 weeks. In each session, HYPO ran 24 min at 70% of maximal O(2) consumption ( [V(02max)) with a breath holding at functional residual capacity whereas CONT breathed normally. A V(02max) and a time to exhaustion test (TE) were performed before (PRE) and after (POST) the training period. There was no change in V(O2max), lactate threshold or TE in both groups at POST vs. PRE. At maximal exercise, blood lactate concentration was lower in CONT after the training period and remained unchanged in HYPO. At 90% of maximal heart rate, in HYPO only, both pH (7.36+/-0.04 vs. 7.33+/-0.06; p<0.05) and bicarbonate concentration (20.4+/-2.9 mmolL(-1) vs. 19.4+/-3.5; p<0.05) were higher at POST vs. PRE. The results of this study demonstrate that VH training did not improve endurance performance but could modify the glycolytic metabolism. The reduced exercise-induced blood acidosis in HYPO could be due to an improvement in muscle buffer capacity. This phenomenon may have a significant positive impact on anaerobic performance.  相似文献   
223.
Few studies reporting long-term results of surgical treatment of hallux rigidus have been published. The aim of this study is to assess the clinical outcome of Valenti procedures in a series of patients with hallux limitus/rigidus with a minimum 10-year follow-up time. We retrospectively evaluated 38 patients (40 feet) who underwent a Valenti procedure with a mean follow-up of 132 ± 19.6 (range 114 to 184) months. All patients were clinically reassessed on the basis of the evaluation of pain (visual analogue scale), function (American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale Assessment and Foot & Ankle Disability Index), and subjective satisfaction. The scores before and after treatment, obtained from clinical recordings and clinical evaluation during the last follow-up visits, were compared. We found significant improvement of the mean values of the visual analogue score (p < .0001), Foot & Ankle Disability Index (p < .0001), and American Orthopaedic Foot and Ankle Society Hallux Metatarsophalangeal-Interphalangeal Scale Assessment (p < .0001) during the latest follow-up visits. The results suggest that the Valenti technique represents a safe, reproducible surgical procedure that allows satisfying long-term results. The few reported complications were essentially the progressive worsening of the joint stiffness, but no sesamoiditis, metatarsal overload, secondary surgeries, or failures were documented.  相似文献   
224.
Background: The aim of the present study is to evaluate the relative abilities of three desensitizing dentifrices to provide rapid relief of dentin hypersensitivity (DH). Methods: Using a double‐mask, randomized design, three dentifrices: 1) containing 8% arginine and 1,450 ppm sodium monofluorophosphate; 2) containing 8% strontium acetate and 1,040 ppm sodium fluoride; and 3) containing 30% microaggregation of zinc‐carbonate hydroxyapatite nanocrystals were compared after 3‐day treatment. Participant's DH was evaluated at baseline and after 3 days using air‐blast, tactile, cold water, and subjective tests. Results: The final sample consisted of 85 individuals: 29 received the arginine‐based dentifrice (group 1), 27 the strontium acetate–based dentifrice (group 2), and 29 the dentifrice based on zinc‐carbonate hydroxyapatite (group 3). All dentifrices were mostly effective to reduce DH: the percentage of score reduction from baseline to 3 days was >30% for all tests (except for subjective test of group 2). The comparison among the three dentifrices showed that, after 3 days, there was an improvement in air‐blast (mean percentage of reduction, 39.2% in group 1, 42.0% in group 2, and 39.2% in group 3), cold water (41.5%, 51.8%, and 50%), tactile (50.3%, 40.1%, and 33.8%), and subjective (33.1%, 17.4%, and 31.4%) test scores, with differences being significant for cold water and subjective tests. For air‐blast and tactile tests, there were no significant differences across groups at 3 days. Moreover, no significant differences at any test were observed in a subset of patients that were followed up to 8 weeks: all dentifrices were all highly efficacious. Conclusions: This study documents that the three tested dentifrices significantly reduced DH after 3‐day treatment, supporting their use in clinical practice. To the best of the authors’ knowledge, this is the first report documenting the rapid relief from DH of a zinc‐carbonate hydroxyapatite dentifrice.  相似文献   
225.
European Spine Journal - A two-staged posterior correction, using a temporary magnetically controlled growing rod (MCGR), was employed to gradually and safely correct severe adolescent idiopathic...  相似文献   
226.
Evidence indicates that oxidative stress refers to a condition where cells are subjected to excessive levels of reactive oxygen species (ROS). Overall vascular function is dependent upon a fine balance between oxidant and antioxidant mechanisms which is required, at least in part, for proper functioning of the endothelium. Considerable experimental and clinical data indicate that the intracellular oxidant milieu is also involved in several redox-sensitive cellular signaling pathways, such as ion transport systems, protein phosphorylation, and gene expression and thus also plays important roles as modulator of vascular cell function, such as cell growth, apoptosis, migration, angiogenesis and cell adhesion. Overproduction of ROS under pathophysiologic conditions is integral in the development of vascular disease. This fact stimulated an intensive search of new pharmacological approaches to improve vascular hemeostasis and, particularly those intended to decrease oxidative stress or augment the antioxidant defense mechanisms.  相似文献   
227.
Chronic interstitial lung disease (ILD) groups a number of diseases with the common feature of radiological pulmonary infiltration, typical functional syndrome, and diffuse involvement of the deep pulmonary parenchyma identified histologically. Correlations between histological and radiological findings have enabled progress in both fields, leading to better interpretation of the radiological findings and optimizing the etiological diagnosis. Besides the signs themselves, their distribution in relation to the normal lung structures is highly contributive. Function tests can be used to quantify the impact on the respiratory system and assess the effect of treatment. Evidence-based criteria will progressively replace the consensual criteria enabling more effective evaluation of treatment in difficult pathological conditions such as idiopathic pulmonary fibrosis.  相似文献   
228.
229.
OBJECTIVE: To assess feasibility, effectiveness and risk of prenatal diagnosis by TA-CVS at 13-14 and 15-20 weeks' gestation. METHODS: CVS was performed transabdominally by free-hand single needle insertion technique under continuous ultrasound visualization on 1844 pregnant women, aged 18 to 48, at 13 to 20 weeks' gestation, whose primary indication was chromosomal anomalies and single gene defects in 85% and 15% of cases, respectively Clinical follow-up of women undergoing TA-CVS at 13 to 20 weeks' was prospectively obtained; the population was split in two groups of 13-14 (series B) and 15-20 weeks' (series C) gestation. Statistical evaluation included a group of TA-CVS cases performed at 11-12 weeks (series A). RESULTS: Sampling was feasible in 98.2%, 99.1% and 95.8% of cases of series A, B and C, respectively. Sampling was successful in all cases of the three series and a second insertion was required in 1.5%, 1.3% and 0.9%, respectively. A trend towards lower fetal loss rate is apparent (1.02%, 0.86%, and 0.46 in series A, B, and C, respectively), although differences were not statistically significant. No post-procedural complications were reported for series B and C, while spotting was present in 1.8% of cases for series A. Karyotyping was totally successful by short term culture and was also available by long term culture in 99% of cases for series A, B and C when the amount of chorionic tissue was more than 15 mg. CONCLUSION: TA-CVS appears highly effective and safe and might be offered as a valuable alternative to early as well as mid-trimester amniocentesis.  相似文献   
230.
Synovial sarcoma of the thoracic spine. A case report   总被引:1,自引:0,他引:1  
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