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51.
Wei Lv PhD Tao Chen ME Yifan Zeng BE Weihong Liu BE Chuying Huang BE 《Journal of Cosmetic Dermatology》2023,22(9):2565-2578
Background
Deep-learning object detection has been applied in various industries, including healthcare, to address hair loss.Methods
In this paper, YOLOv5 object detection algorithm was used to detect hair follicles in a small and specific image dataset collected using a specialized camera on the scalp of individuals with different ages, regions, and genders. The performance of YOLOv5 was compared with other popular object detection models.Results
YOLOv5 performed well in the detection of hair follicles, and the follicles were classified into five classes based on the number of hairs and the type of hair contained. In single-class object detection experiments, a smaller batch size and the smallest YOLOv5s model achieved the best results, with an map of 0.8151. In multiclass object detection experiments, the larger YOLOv5l model was able to achieve the best results, and batch size affected the result of model training.Conclusion
YOLOv5 is a promising algorithm for detecting hair follicles in a small and specific image dataset, and its performance is comparable to other popular object detection models. However, the challenges of small-scale data and sample imbalance need to be addressed to improve the performance of target detection algorithms. 相似文献52.
Yongheon Kim BE Hyunseon Yu MS Sunghwan An MD Donghoon Ha BE Byungjo Jung PhD 《Journal of Cosmetic Dermatology》2023,22(11):2982-2988
Objective
Although focused ultrasound modalities have achieved positive clinical results in noninvasive skin rejuvenation, they presented various side effects and particularly severe pain during treatment. This study introduces a microfocused ultrasound (MFU) device, ULTIGHT, to overcome the severe pain issue, providing quasi-facial lifting.Materials and Methods
Transducer surface was imaged with a scanning electron microscope. The energies of four treatment cartridges were measured using an ultrasound power meter. In vitro experiments were performed to quantitatively evaluate the MFU thermal zones (MFUTZs) and treatment line (TL) of 10 MFUTZs. Ex vivo experiments were performed to evaluate the MFUTZs and temperature rise in tissue. Clinical trials using eight volunteers were performed to qualitatively evaluate facial lifting.Results
The MFU transducer clearly showed a smooth and no air gap surface. ULTIGHT produced 10 discrete MFUTZs in a TL of length 10 mm. In ex vivo tissue, discrete linear MFUTZs were clearly observed at lower number of TLs; however, they started to aggregate at higher number of TLs. The temperature rise was linearly increased as a function of the number of treatments. A single MFUTZ resulted in a temperature rise of 3°C–10°C that could cause hyperthermia for body temperature. In the clinical trials, the volunteers showed quasi-facial lifting right after treatment on the lower facial region.Conclusions
ULTIGHT provides relatively low energy, which may be advantageous or disadvantageous depending on clinical applications. Additionally, it has the advantage of being pain-free even without anesthetic during treatment, providing quasi-facial lifting right after treatment. 相似文献53.
54.
Role of nitric oxide in regulation of coronary blood flow during myocardial ischemia in dogs 总被引:6,自引:0,他引:6
Masafumi Kitakaze Md Koichi Node MD Tetsuo Minamino MD Hiroaki Kosaka MD Yoshiro Shinozaki BE Hidezo Mori MD Michitoshi Inoue MD Masatsugu Hori MD Takenobu Kamada MD 《Journal of the American College of Cardiology》1996,27(7):1804-1812
Objectives. This study was undertaken to examine whether nitric oxide released in ischemic myocardium decreases the coronary vascular resistance and attenuates the severity of contractile and metabolic dysfunction.Background. Endothelium-derived relaxing factor, recently identified as nitric oxide, is a potent relaxant of coronary smooth muscle.Methods. The left anrterior descending coronary artery was perfused through an extracorporeal bypass tube placed in the carotid artery in 56 open chest dogs. After hemodynamic stabilization, we occluded this bypass tube to decrease coronary blood flow to one third of the control flow. Thereafter, we maintained a constant coronary perfusion pressure(40.9 ± 3.1mm Hg).Results. Under ischemic conditions, the coronary arteriovenous differences in nitrate and nitrite (end products of nitric oxide) increased (from 3.5 ± 0.4 [mean ± SEM] to 12.9 ± 2.1 μmol/liter, p < 0.01).
0-Monomethyl
-arginine (3 μg/kg body weight per min, intracoronary) decreased the coronary arteriovenous differences in nitrate and nitrite (5.0 ± 0.9 μmol/liter, p < 0.05) and coronary blood flow (from 29.8 ± 0.5 to 18.1 ± 1.1 ml/100 g per min, p < 0.001). Fractional shortening (from 3.7 ± 1.0 to −1.3 ± 0.7%, p < 0.001) and lactate extraction ration (from −44.0 ± 4.1 to −59.2 ± 4.9%, p < 0.005) of the perfused area also decreased. These values were restored by the concomitant administration of
-arginine. Blood flow to the endomyocardium was decreased relative to the epimyocardium. A reduction in coronary blood flow and worsening of myocardial contractile and metabolic functions due to the administration of
G-monomethyl
-arginine during ischemia were observed in denervated hearts. A reduction in coronary blood flow in ischemic myocardium was observed with the administration of
W-nitro-
-arginene methyl ester as well, although neither
W-nitro-
-arginine methyl ester nor
G-monomethyl
-arginine changed coronary blood flow and myocardial contractile and metabolic functions in the nonischemic myocardium. The cyclic guanosine monophosphate content of epicardial coronary artery increased due to myocardial ischemia; this increased was attenuated with
G-monomethyl
-arginine treatment.Conclusions. We conclude that endogenous nitric oxide predominantly decreases the coronary vascular resistance of ischemic endomyocardium, thereby improving myocardial contractility and metabolic function. 相似文献
55.
Impact of Insurance Provider on Overall Costs in Failed Back Surgery Syndrome: A Cost Study of 122,827 Patients 下载免费PDF全文
56.
The Influence of Skin Redness on Blinding in Transcranial Direct Current Stimulation Studies: A Crossover Trial 下载免费PDF全文
57.
58.
Laura BE Kienhorst Hein JEM Janssens Matthijs Janssen 《World Journal of Rheumatology》2014,4(3):62-71
Gout is a common disease caused by the deposition of monosodium urate(MSU) crystals in patients with hyperuricemia, and characterized by very painful recurrent acute attacks of arthritis. The gold standard for diagnosing gout is the identification of MSU crystals in synovial fluid by polarization light microscopy. Arthritis attacks can be treated with anti-inflammatory medications, such as non-steroidal anti-inflammatory drugs, colchicine, oral prednisone, or intra-articular or intramuscular glucocorticoids. To prevent gout uric acid lowering therapy with for example allopurinol can be prescribed. When gout is adequately treated, the prognosis is good. Unfortunately, the management of gout patients is often insufficient. Gout is associated with dietary factors, the use of diuretics, and several genetic factors. Comorbidities as hypertension, chronic kidney disease, cardiovascular diseases, the metabolic syndrome, diabetes, obesity, hyperlipidemia, and early menopause are associated with a higher prevalence of gout. Xanthine oxidase and chronic systemic inflammation seem to play an important role in the pathophysiology of the association between gout and cardiovascular diseases. To prevent cardiovascular diseases goutpatients must be early screened for cardiovascular risk factors. 相似文献
59.
Sherifa A Hamed Yaser BE Elserogy Madleen A Abdou Mostafa M Abdellah 《World Journal of Psychiatry》2012,2(2):33-42
AIM: To determine the prevalence and risks of suicidality in a group of patients with epilepsy.
METHODS: Included were 200 adult patients and 100 matched healthy subjects. The clinical interview using The Diagnostic and Statistical Manual of Mental Disorders (4th edition), Beck Depression Inventory (2nd edition) (BDI-II), Hamilton Anxiety Rating Scale (HAM-A), Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and Eysenck Personality Questionnaire-Revised Rating Scale testings were used for diagnosis and assessment of severity of psychiatric symptoms. Blood concentrations of serotonin, catecholamines and dopamine were also measured.
RESULTS: Suicidality was reported in 35% (compared to 9% for controls), of them 80%, 72.86%, 55.71% and 52.9% had depression, anxiety, obsession and aggression respectively. Patients with suicidality had higher scores of BDI-II (P = 0.0001), HAM-A (P = 0.0001), and Y-BOCS (P = 0.037) and lower scores of psychotic (P = 0.0001) and extroversion (P = 0.025) personality traits. Regardless the presence or absence of suicidality, patients with epilepsy had low serotonin (P = 0.006), noradrenaline (P = 0.019) and adrenaline (P = 0.0001) levels. With suicidality, significant correlations were identified between: (1) age and scores of BDI-II (r = 0.235, P = 0.0001) and HAM-A (r = 0.241, P = 0.046); (2) age at onset and concentrations of noradrenaline (r = -0.502, P = 0.024); (3) duration of illness and scores of BDI-II (r = 0.247, P = 0.041), Y-BOCS (r = 0.270, P = 0.025) and neurotic personality trait (r = -0.284, P = 0.018); and (4) doses of antiepileptic drugs and scores of psychotic personality traits (r = -0.495, P = 0.006 for carbamazepine; r = -0.508, P = 0.0001 for valproate).
CONCLUSION: This is the first study which systematically estimated the prevalence and risks of suicidality in a homogenous group of patients with epilepsy. This study emphasizes the importance of epilepsy itself as a risk for suicidality and not its treatment. 相似文献
60.
Reliability and Validity of the PAQ‐C Questionnaire to Assess Physical Activity in Children 下载免费PDF全文