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41.
Transient left ventricular apical ballooning syndrome is characterized by reversible left ventricular wall motion abnormalities, chest pain or dyspnea, ST-segment elevation, and mild elevation of cardiac enzyme levels in the absence of obstructive coronary artery disease. The pathophysiology of the syndrome is still unknown. The probable mechanism is supposed to be a catecholamine discharge. We report the case of a 66-year-old woman with recently diagnosed pheochromocytoma who presented with chest pain and ST-segment elevation. Coronary angiography revealed normal coronaries and apical dyskinesia at ventriculography. A similar episode of chest pain occurred 4 years ago with same angiographic findings and reversible inferobasal akinesia. In-hospital course was uneventful and the patient was discharged from the hospital 4 days later with treatment of aspirin 1 × 100 mg, metoprolol 1 × 50 mg, lisinopril 1 × 10 mg, and atorvastatin 1 × 20 mg. At 2 years follow-up after the event, the patient remained asymptomatic.  相似文献   
42.
Purpose: To evaluate whether patent foramen ovale (PFO) is a contributing factor to hypoxia in patients with chronic obstructive pulmonary disease (COPD). Methods: Twenty‐one patients over 40 years of age with mild COPD (Forced expiratory volume (FEV1)/Forced Vital Capacity (FVC): > 50%) who had hypoxia (PO2 < 80 mmHg, SaO2 < 95%) that could not be explained by COPD alone were included in this study. Arterial oxygen pressures (PO2) and arterial oxygen saturations (SaO2) were recorded from laboratory evaluations of arterial blood gases. Respiratory function tests were performed to analyze the degree of COPD. Standard and contrast echocardiography was used to calculate pulmonary artery pressure (PAP) levels and to determine patients with a PFO. Results: The mean age of the patients was 64 ± 12 years. Four patients (19%) had a PFO. The mean PO2, mean SaO2, and mean PAP levels were 57.4 ± 6.8 mmHg, 90 ± 3.2%, and 33.8 ± 5.4 mmHg, respectively, in patients without PFO. The mean PO2, mean SaO2, and mean PAP levels were 46.5 ± 13.7 mmHg, 79.3 ± 12.8%, and 42.5 ± 6.5 mmHg, respectively, in patients with PFO. There were no statistically significant differences noted between the two groups in the PO2 levels (P = 0.172) and SaO2 levels (P = 0.065). A comparison of the PAP levels revealed a statistically significant difference between the two groups, with values that were more elevated in the PFO group than in the non‐PFO group (P = 0.031). Conclusion: This study demonstrated that PFO is not a contributing factor to deep hypoxia in COPD patients with lower PO2 and SaO2 levels; however, higher PAP levels were detected in patients with a PFO. Further studies involving a larger number of patients are needed to be conclusive. (Echocardiography 2010;27:687‐690)  相似文献   
43.
Objective: The purpose of the current study was to investigate the possible effects of phototherapy on bone status of term infants evaluated by measurement of tibial bone speed of sound (SOS).

Materials and methods: The phototherapy group (n?=?30) consisted of children who had undergone phototherapy for at least 24?h and the control group (n?=?30) comprised children who had not received phototherapy. Blood samples were obtained from all infants for serum calcium, phosphorus, magnesium, alkaline phosphatase, parathyroid hormone and vitamin D concentrations. The left tibial quantitative ultrasound (QUS) measurements were performed using a commercial device.

Results: There was no statistically significant difference between phototherapy-exposed and nonexposed infants in terms of Ca, P, ALP, PTH and vitamin D levels. Comparison of bone SOS between the phototherapy-exposed and control group revealed no statistically difference. Also, no significant difference in Z-score for SOS was observed between those with or without exposure.

Conclusion: The data of our study indicate that phototherapy treatment has no impact on bone status in the hyperbilirubinemic infants. Although there is no statistically significant evidence of an excess risk of bone damage following phototherapy, studies with larger sample sizes and longer duration of follow-up are needed to gain a better understanding of its effects.  相似文献   
44.
Congenital absence of uterus and vagina, the Mayer-Rokitansky-Küster-Hauser Syndrome (MRKHS), results from defective müllerian duct development during female embryogenesis; it is the second most common cause of primary amenorrhea. Atypical forms of MRKHS (type B) represent a heterogeneous group of disorders with associated anomalies of other organ systems which frequently includes the renal and skeletal systems and several individually occurring malformations.We report two cases with MRKHS in which we diagnosed situs inversus totalis incidentally during radiologic examinations. Abdominal situs inversus describes the mirror-image arrangement of the intra-abdominal organs in the abdominal cavity and it is characterized by the presence of multiple congenital anomalies.In this report we attempt to question whether the association between MRKHS and situs inversus is a rare feature of the müllerian dysgenetic spectrum or whether it is the result of random association.  相似文献   
45.
The aim of this study was to determine left ventricular (LV) morphology and aortic function in power athletes and to compare them with normal subjects. Thirty-two elite male wrestlers and 15 age-matched healthy male controls were included. All subjects underwent echocardiographic examination. Measurements included LV cavity dimension at systole and diastole, wall thickness, diastolic parameters, and aortic diameter, 3cm above aortic valve, at systole and diastole. Left ventricular mass and mass index were found to be higher in the athletes than in control subjects. The aortic distensibility index was found to be reduced in the athletes compared with controls (2.53 ± 0.91 vs 3.94 ± 1.77cm2dyne–1 10–6, P = 0.003), while the aortic stiffness index was significantly higher in the athletes than in controls (9.12 ± 3.23 vs 6.65 ± 2.35, P = 0.02). However, LV end-systolic wall stress was lower in the athletes than in controls. Furthermore, transmitral early (E) and late (A) peak velocity, peak velocity of the myocardial systolic wave (S m), and early (E m) and atrial (A m) diastolic waves at the inferior wall were higher in the athletes than in controls. Reduced aortic distensibility in elite power athletes may be one of the cardiovascular adaptation factors which affect LV hypertrophy.  相似文献   
46.
The angiotensin II receptor, losartan, has been found to inhibit platelet aggregability to some extent in in vitro experiments. There have been conflicting results about the in vivo effects of losartan. We sought to clarify the in vivo effect of losartan on platelet aggregation. Forty patients with grade I essential hypertension were treated with losartan for 3 weeks. Platelet aggregation tests with adenosine diphosphate (ADP) and ristocetin were analyzed and compared before and at the end of the study. Losartan effectively decreased systolic (SBP) and diastolic (DBP) blood pressure. Mean SBP before and after treatment was 159.6 ± 12.8 and 149.2 ± 17.3mmHg, respectively. Mean DBP decreased from 93.7 ± 8.2 to 87.7 ± 10.3mmHg after treatment. The results of the platelet aggregation tests with ADP and ristocetin were not significantly different when both rate and amplitude of maximal aggregation were included. Peak platelet aggregation with ADP regarding the lowest light transmission in the aggregometer was 59.8% ± 24.3% before and 58.3% ± 18.1% after the treatment. The same variables with ristocetin were 66.8% ± 21.6% and 60.8% ± 23.3%, respectively. In vivo effects of losartan on platelet aggregation with ADP and ristocetin were insignificant.  相似文献   
47.
It is known that cold exposure is accompanied by coronary artery vasoconstriction and ischemia in patients with coronary artery disease (CAD). The aim of the present study was to evaluate the response of left ventricular (LV) diastolic and systolic functions, estimated by means of Doppler echocardiography, to cold pressor test (CPT) in patients with CAD. Twenty-five male patients (mean age 50.8 +/- 8.1 years) with documented CAD underwent CPT with Doppler echocardiographic assessment of LV diastolic and systolic functions. According to the development of ischemic response to CPT, all patients were divided into 2 groups: group 1, 10 patients with ischemia and group 2, 15 patients without ischemia during CPT. Cold exposure caused significant increase in blood pressure with no changes in heart rate in all CAD patients. Patients with signs of ischemia during cold exposure had lower transmitral flow velocity during early filling (p < 0.001), prolonged isovolumic relaxation time (p < 0.04), shortened deceleration time of early transmitral flow velocity (p < 0.001), and higher values of Doppler-derived index of myocardial performance (p < 0.0001) than those without ischemic response to CPT. Cold exposure in CAD patients through stimulating of vasoconstriction and ischemia was associated with derangements in LV myocardial performance, manifested by delayed relaxation, impaired stiffness, and reduced contractility.  相似文献   
48.
49.
Isolated TSH deficiency is a rare cause of congenital hypothyroidism. We here report four children from two consanguineous Turkish families with isolated TSH deficiency. Affected children who were screened at newborn age had an unremarkable TSH result and a low serum TSH level at diagnosis. Age at diagnosis and clinical phenotype were variable. All affected children carried an identical homozygous splice site mutation (IVS2 + 5 G--> A) in the TSHbeta gene. This mutation leads to skipping of exon 2 and a loss of the translational start codon without ability to produce a TSH-like protein. However, using specific monoclonal antibodies, we detected a very low concentration of authentic, heterodimeric TSH in serum, indicating the production of a small amount of correctly spliced TSH mRNA. By genotyping all family members with polymorphic markers at the TSHbeta locus, we show that the mutation arose on a common ancestral haplotype in three unrelated Turkish families indicating a founder mutation in the Turkish population. These results suggest that this TSHbeta mutation is among the more common TSHbeta gene mutations and stress the need for a biochemical and molecular genetic workup in children with symptoms suggestive of congenital hypothyroidism, even when the neonatal TSH screening is normal.  相似文献   
50.
Background: Although internal cardioversion (IC) for atrial fibrillation (AF) is effective at restoring sinus rhythm, immediate recurrence (IR) of AF after IC is a major and largely unpredictable clinical problem. The purpose of the study was to determine the role of P wave duration and amplitude in prediction of IR of AF after IC. Forty‐five consecutive patients undergoing IC for chronic AF were evaluated. Material and Methods: After successful IC, 1‐minute ECG recording was obtained in all patients. P wave duration and amplitude in Lead II and V1 were measured using computer. Forty patients (88%) had successful IC. Thirteen patients experienced IR of AF within 1 minute of restoring sinus rhythm. Results and Conclusion: As a result, the incidence of IR of AF after IC was higher in the patients with shorter P wave amplitude (for lead II P < 0.01 , for V1P < 0.01 ) and larger P wave duration (for lead II P < 0.01 , for V1P < 0.05 ).  相似文献   
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