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Data on coronary flow reserve (CFR) in patients with syndrome X are still controversial. Further, noninvasive evaluation of epicardial and microvascular flow reserves in these patients has never been performed. In 17 patients with syndrome X and in 17 age- and gender-matched control subjects, CFR in the mid left anterior descending coronary artery (LAD) was evaluated by transthoracic color and pulse-wave Doppler using a 7-mHz probe (Sequoia, Siemens). Peak diastolic LAD flow was calculated at rest and at peak adenosine (140 microg/kg/min intravenously in 90 seconds). Myocardial contrast echocardiography (MCE) was performed at rest and during adenosine use by real-time cadence pulse sequencing and intravenous SonoVue (Bracco; 5 ml at 1 ml/min) and microvascular blood volume (A), velocity (beta), and flow (Axbeta) by replenishing curves (y = A[1 - e(betat)]). CFR was measured by Doppler echocardiography as an adenosine/rest velocity ratio and by MCE as a microvascular volume, velocity, and flow adenosine/rest ratio. Compared with controls, patients with syndrome X demonstrated lower LAD CFR and velocity and flow microvascular flow reserves (p <0.01, <0.005, and <0.005, respectively). In patients with syndrome X, those with angina and ST-segment depression during adenosine testing had even lower LAD CFR and velocity and flow microvascular flow reserves compared with those with no symptoms (p <0.0001, <0.0001, and <0.005, respectively). LAD CFR demonstrated a significant linear correlation with velocity microvascular flow reserve (r = 0.92, p <0.0001) and flow microvascular flow reserve (r = 0.77, p <0.0001). In conclusion, CFR in the LAD, successfully evaluated by transthoracic Doppler echocardiography and MCE, is significantly decreased in patients with syndrome X and even more in those with angina pectoris and ST-segment depression during adenosine testing. Thus, noninvasive evaluation of CFR by echocardiography is feasible and provides information on the severity of microvascular impairment.  相似文献   
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BACKGROUND: Cardiac abnormalities develop in patients with acromegaly as a consequence of effects of GH/IGF-I on the heart and related cardiovascular risk factors. OBJECTIVE: To evaluate the possible contribution of postoperative variations in blood pressure (BP), glucose tolerance and insulin sensitivity to the cardiac improvement reported in patients who have been cured of acromegaly. DESIGN: Thirty-one patients with acromegaly were studied before and 6 Months after successful transsphenoidal surgery, defined by normal age-related IGF-I concentrations and glucose-suppressed GH concentrations <1 microg/l. METHODS: Cardiovascular parameters were assessed by Doppler echocardiography and 24-h ambulatory blood pressure monitoring. Insulin sensitivity indexes were calculated on the basis of fasting and post-load glycaemia and insulinaemia and referred to as HOMA(ISI) and OGTT(ISI), respectively. RESULTS: Successful surgery was confirmed to improve left ventricular mass index (LVMI) and diastolic filling significantly. Mean 24-h systolic BP values decreased (P=0.009) and BP rhythm was restored in 12 of 15 patients with a blunted preoperative profile. Glucose tolerance normalized in patients with preoperative glucose intolerance (n=7) or diabetes mellitus (n=3). HOMA(ISI) and OGTT(ISI) increased (P=0.0001 for each parameter), indicating a marked improvement in insulin sensitivity. The postoperative reduction in LVMI correlated with increased insulin sensitivity (P<0.001 for both indexes), but not with other parameters. Improved diastolic filling correlated with the reduction in LVMI. CONCLUSIONS: Successful surgery in patients with acromegaly induces a significant improvement in haemodynamic and metabolic risk factors. This study suggests a direct link between insulin resistance and acromegalic cardiomyopathy.  相似文献   
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Objective

To assess morphology and blood flow of the proper palmar digital arteries (PPDA) by Color Doppler Ultrasonography (CDUS) and its relationship with nailfold videocapillaroscopy (NVC), skin blood perfusion and digital arteries pulsatility of hands in SSc patients and healthy controls.

Methods

CDUS, NVC, Laser Doppler Perfusion Imaging (LDPI) and photoplethysmography (PPG) were performed in 36 systemic sclerosis (SSc) patients and 20 healthy controls.

Results

CDUS was pathologic in 69% of patients with SSc and in none of healthy controls (p < 0.0001). SSc patients with low vascular damage (early capillaroscopic pattern) have a normal morphology of PPDA, but the blood flow, evaluated by peak systolic velocity (PSV) and end diastolic velocity (EDV), is reduced and vascular resistance, measured by resistive index (RI) and pulsatility index (PI), increased. At this stage the LDPI mean perfusion and digital artery pulsatility, evaluated by PPG, were reduced. The US changes appear with microvasculare damage progression (active and late capillaroscopic patterns), while the PPDA blood flow progressively decreases (PSV and EDV decreased, RI and PI increased). The macrovascular damage correlates with disease duration. Anti-topoisomerase I represents an independent predictive factor for macrovascular damage. We not observed any association between digital ulcer history, pulmonary fibrosis and US findings.

Conclusion

PPDA blood flow dysfunction is already present in early disease. Structural macrovascular damage progresses with worsening of SSc microangiopathy.  相似文献   
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OBJECTIVES: The purpose of this study was to investigate whether a direct relation can be demonstrated between myocardial perfusion defects detected during dobutamine stress test (DST) by cardiovascular magnetic resonance (CMR) and impairment of coronary microvascular dilatory function in patients with cardiac syndrome X (CSX). BACKGROUND: Despite the fact that coronary microvascular dysfunction has been shown in most patients with CSX, the ischemic origin of CSX remains debated. No previous study assessed whether a strict relation exists between abnormalities in myocardial perfusion and coronary microvascular dysfunction in CSX patients. METHODS: Eighteen CSX patients (mean age 58 +/- 7 years, 7 men) and 10 healthy control subjects (mean age 54 +/- 8 years, 4 men) underwent myocardial perfusion study by gadolinium-enhanced CMR at rest and at peak DST (maximal dose 40 microg/kg/min). Coronary flow response (CFR) to adenosine (140 microg/kg/min in 90 s) in the left anterior descending (LAD) coronary artery was assessed by high-resolution transthoracic echo-Doppler and expressed as the ratio between coronary flow velocity at peak adenosine and at rest. RESULTS: At peak DST, reversible perfusion defects on CMR were found in 10 CSX patients (56%) but in none of the control subjects (p = 0.004). The CFR to adenosine in the LAD coronary artery was lower in CSX patients than in control subjects (2.03 +/- 0.63 vs. 3.29 +/- 1.0, p = 0.0004). The CSX patients with DST-induced myocardial perfusion defects in the LAD territory on CMR had a lower CFR to adenosine compared with those without perfusion defects in the LAD territory (1.69 +/- 0.5 vs. 2.31 +/- 0.6, p = 0.01). A significant correlation was found in CSX patients between CFR to adenosine and a DST perfusion defect score on CMR in the LAD territory (r = -0.45, p = 0.019). CONCLUSIONS: Our data concurrently show DST-induced myocardial perfusion defects on CMR and reduced CFR in the LAD coronary artery territory in CSX patients, thus giving strong evidence that a dysfunction of coronary microcirculation resulting in myocardial perfusion abnormalities is present in these patients.  相似文献   
38.
It is well known that physical activity can aggravate the intensity of the headache, but the pathophysiological relationship between exertion and aura is still unknown. Anecdotal reports describe episodes of migraine preceded by head trauma and visual symptoms, migraine prodrome symptoms after unusually strenuous running with no subsequent head pain or recurrent attacks of hemiplegic migraine induced only by exertion. We describe the cases of three young men with recurrent episodes of migraine with aura occurring in the locker room shortly after a football match. Since the symptoms could mimic important pathologies in approximately 10% of these of headaches, it was mandatory to exclude a secondary form of headache in these patients. Several theories exist regarding the cause of primary exertional headache, but the pathogenesis of migraine triggered by physical activity has still not been identified. The present International Classification of Headache Disorders does not mention sport/exercise-induced migraine with aura episodes as primary headache. Since there are many cases described in the literature of migraine with aura triggered only by exercise, it may be helpful to specify, in the typical aura with migraine headache comments, that in some cases it can be exclusively triggered by sport/exercise.  相似文献   
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This study aimed at determining the causes of failure of the different proposed strategies to ensure improvement of medication-overuse headache (MOH) patients, since they have not been investigated so far, especially with regard to aspects related to cognitive and behavioural aspects of symptomatic drugs overused by them. One hundred and twenty in-patients, 82 females (68.3 %), median age 49 (42–56) years, affected by MOH were admitted to the study and treated with abrupt discontinuation of the medication overused, a 6-day in-patient detoxification regimen and an immediate start of personalized prophylactic treatment, then followed for 1 year. Leeds Dependence Questionnaire (LDQ), among all the clinical variables, was administered at baseline and at 1-year follow-up visit to assess substance dependence. Of the 120 patients enrolled, 68 (56.7 %) were successfully detoxified (Responder-group), while 52 (43.3 %) were not (Non-Responder-group). At baseline, the mean LDQ total score was slightly higher in the Non-Responder group than in the Responder group (12.08 ± 2.14 vs. 11.94 ± 1.98). Although this difference was not significant at baseline (p > 0.05), the LDQ total score was significantly different (p < 0.001) at the 1-year follow-up visit between the responder group (7.8 ± 2.3) and the Non-Responder group (12.1 ± 2.1). Moreover, the pattern of the responses of the patients in the responder group differed from that of the Non-Responder-group in the items relating to the compulsion to start, compulsion to continue, primacy of effect, constancy of state and cognitive set. The results showed that patients of the Non-Responder group showed a drug dependence pattern similar to that previously described in addicts. Conversely, in patients who positively responded to the procedure, drug-abuse behaviour seemed to be a consequence of chronic headache, reflecting the need for daily analgesic use to cope with everyday life.  相似文献   
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In the last few years,the advent of next generation sequencing(NGS) has revolutionized the approach to genetic studies,making whole-genome sequencing a possible way of obtaining global genomic information.NGS has very recently been shown to be successful in identifying novel causative mutations of rare or common Mendelian disorders.At the present time,it is expected that NGS will be increasingly important in the study of inherited and complex cardiovascular diseases(CVDs).However,the NGS approach to the genetics of CVDs represents a territory which has not been widely investigated.The identification of rare and frequent genetic variants can be very important in clinical practice to detect pathogenic mutations or to establish a profile of risk for the development of pathology.The purpose of this paper is to discuss the recent application of NGS in the study of several CVDs such as inherited cardiomyopathies,channelopathies,coronary artery disease and aortic aneurysm.We also discuss the future utility and challenges related to NGS in studying the genetic basis of CVDs in order to improve diagnosis,prevention,and treatment.  相似文献   
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