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991.

Background

Coronary slow flow (CSF) phenomenon is characterized by delayed opacification of coronary vessels in a normal coronary angiogram. Although clinical and pathological features have been previously described, the underlying pathophysiology has not been fully elucidated. We aimed to determine and compare the carotid intima-media thickness (CIMT) values of SCF patients and healthy subjects, and to correlate patients’ values with intimal thickness and TIMI frame counts of their coronary arteries (assessed by intravascular ultrasound).

Methods

The study population consisted of 50 patients with SCF [38(76%) male, aged 53 ± 7 years] and 40 normal subjects [22(55%) male, aged 51 ± 8 years]. CIMT values, intravascular ultrasonographies and TIMI frame counts of the patients, and CIMT of the controls were investigated.

Results

Upon intravascular ultrasonography investigation, the common finding was longitudinally extended massive calcification throughout the epicardial coronary arteries in 44 (88%) of patients. Mean coronary intimal thickness was 0.52 ± 0.1 mm. CIMT was significantly increased in SCF patients than controls (0.84 ± 0.14 vs. 0.66 ± 0.13, p < 0.0001). Besides, CIMT was significantly correlated with coronary intima-media thickness. TIMI frame counts were positively correlated with CIMT and coronary intimal thickness (p < 0.05 and p < 0.05 respectively).

Conclusion

These results support the theory that SCF is the result of coronary atherosclerosis which is the part of systemic involvement.  相似文献   
992.
Inflammatory markers are elevated in acute coronary syndromes, and are also known to play a crucial role in the pathogenesis of neointimal proliferation and stent restenosis. Drug-eluting stents (DESs) have been shown to decrease stent restenosis in different studies. In this study, we aimed to investigate the effect of treatment with DESs on systemic inflammatory response in patients with unstable angina pectoris who underwent percutaneous coronary intervention (PCI). We compared plasma high-sensitivity C-reactive protein (hsCRP), human tumor necrosis factor α (Hu TNF-α), and interleukin 6 (IL-6) levels after DES (dexamethasone-eluting stent [DEXES], and sirolimuseluting stent [SES]) implantation with levels after bare metal stent (BMS) implantation. We performed PCI with a single stent in 90 patients (62 men; 59 ± 9 years of age; n = 30 in the BMS group, n = 30 in the DEXES group, n = 30 in the SES group) who had acute coronary syndrome. Plasma hsCRP, Hu TNF-α, and IL-6 levels were determined before intervention and at 24 h, 48 h, and 1 week after PCI. The results were as follows. Plasma hsCRP levels at 48 h (11.19 ± 4.54, 6.43 ± 1.63 vs 6.23 ± 2.69 mg/l, P = 0.001) after stent implantation were significantly higher in the BMS group than in the DES group; this effect persisted for 7 days (P = 0.001). Plasma Hu TNF-α levels at each time point were higher in the SES group than in the BMS and DEXES groups (P < 0.05). The time course of Hu TNF-α values was similar in all groups. Although IL-6 levels at baseline and at 24 and 48 h showed no statistically significant difference between the study groups, postprocedural values at 7 days were slightly statistically significant in the SES group (P = 0.045). Drug-eluting stents showed significantly lower plasma hsCRP levels after PCI compared with BMSs. This may reflect the potent effects of DESs on acute inflammatory reactions induced by PCI.  相似文献   
993.
It has been reported that some patients with Type 2 diabetes mellitus (DM) have latent autoimmune diabetes in adults (LADA) and may show different clinical characteristics than those with Type 2 DM. We aimed to determine the ratio and clinical features of LADA in patients with diagnosed initially as Type 2 DM. We measured glutamic acid decarboxylase antibodies (GADA) in 54 patients, diagnosed clinically with Type 2 DM. Of 54 patients, 17 (31%) were GADA positive. GADA-positive patients had significantly earlier diabetes onset age (P<.001), lower BMI (P<.05), and lower serum C-peptide value (P<.001) than did those who were GADA negative. A higher proportion of the GADA-positive patients were receiving insulin therapy (P<.01). With respect to the duration of DM, familial history of DM, and the levels of blood pressures, fasting plasma glucose, and HbA1c, there was no difference between the two groups. Nephropathy and retinopathy were more frequent in GADA-positive than in GADA-negative patients. The prevalence of neuropathy was comparable between the two groups. GADA was negatively associated with BMI, C-peptide levels, and diabetes-onset age, but positively related to retinopathy, nephropathy, and insulin treatment. This study indicated that the important portion of the patients who were initially diagnosed as Type 2 DM may have LADA. In Type 2 diabetic patients who have lower BMI and diagnosis of diabetes in relatively younger age, the possibility of LADA should be taken into consideration. The higher prevalence of nephropathy and retinopathy in GADA-positive patients also suggests the importance of early diagnosis and strict metabolic control in these patients.  相似文献   
994.
995.
Mammalian airways protect themselves from bacterial infection by using multiple defense mechanisms including antimicrobial peptides, mucociliary clearance, and phagocytic cells. We asked whether airways might also target a key bacterial cell-cell communication system, quorum-sensing. The opportunistic pathogen Pseudomonas aeruginosa uses two quorum-sensing molecules, N-(3-oxododecanoyl)-l-homoserine lactone (3OC12-HSL) and N-butanoyl-l-homoserine lactone (C4-HSL), to control production of extracellular virulence factors and biofilm formation. We found that differentiated human airway epithelia inactivated 3OC12-HSL. Inactivation was selective for acyl-HSLs with certain acyl side chains, and C4-HSL was not inactivated. In addition, the capacity for inactivation varied widely in different cell types. 3OC12-HSL was inactivated by a cell-associated activity rather than a secreted factor. These data suggest that the ability of human airway epithelia to inactivate quorum-sensing signal molecules could play a role in the innate defense against bacterial infection.  相似文献   
996.
OBJECTIVE: To determine the effects of the thermolabile methylene tetrahydrofolate reductase (MTHFR) mutation on the presence and extent of coronary atherosclerosis in a population with low plasma folate. METHODS: 242 consecutive patients undergoing coronary angiography were prospectively evaluated for conventional risk factors, plasma homocysteine, vitamin B-12, and folate, and MTHFR genotype. The severity of coronary atherosclerosis was determined by the Leaman score. RESULTS: Mean (SD) plasma homocysteine was 15.6 (10) micromol/l in controls and 18.5 (11) micromol/l in patients with coronary artery disease (p > 0.05). Plasma homocysteine concentrations above 15 micromol/l were a risk factor for coronary artery disease (p = 0.03, risk ratio 2.1, 95% confidence interval (CI) 1.07 to 4.4). Homocysteine remained an independent risk factor on multivariate analysis when conventional risk factors were taken into account (p = 0.04). Homocysteine concentrations above 15 micromol/l were correlated with the extent of atherosclerosis (p = 0. 04, risk ratio 3.2, 95% CI 1.3 to 8.2). Homocysteine had no effect on other lipid variables (p > 0.05). Plasma folate was 15.8 (7.2) nmol/l in controls and 11.5 (2.9) nmol/l in patients with coronary artery disease. Plasma folate concentrations below 12.9 nmol/l (5.7 ng/ml) conferred a risk for coronary artery disease (p = 0.03, risk ratio 2.42, 95% CI 1.05 to 5.59). When the MTHFR genotype was determined, the TT genotype was present in 7.4% of patients and 5.2% of controls (p > 0.05). The prevalence of alleles was within the Hardy-Weinberg equilibrium (TT 7, CT 40, CC 53, chi2 = 2.3, p = 0.3). The highest homocysteine concentrations were found in patients with the TT genotype and folate below the median of the population (p = 0. 01). The extent of coronary atherosclerosis judged by the Leaman score was significantly higher in patients with the TT genotype (p = 0.03). CONCLUSIONS: Plasma homocysteine over 15 micromol/l was a significant risk factor for the presence and extent of coronary artery disease. The mean plasma folate of the population was low and correlated negatively with homocysteine. Although TT genotype was not an independent predictor of coronary artery disease, it was an important predictor of the extent of coronary atherosclerosis and plasma homocysteine, especially in the presence of plasma folate values below the median of the population. These findings may have important implications for folate replacement in patients with the TT genotype.  相似文献   
997.
Transanal endoscopic microsurgery is a minimally invasive technique for the treatment of rectal lesions which was introduced by Buess. In this report the first clinical experience of transanal endoscopic surgery was performed by a single incision laparoscopic surgical port adapted through the anal canal. In single port surgery, the single incision laparoscopic surgical port has to be stitched around anal orifice. There is no need to use a fixation apparatus. In transanal endoscopic microsurgery procedure, a rigid rectoscope 40 mm in diameter is introduced into the anus by stretching anal sphincter. A single incision laparoscopic surgical port can be disposed through the anal canal where there is no harmful cause because it is made an elastic. The dissection in the transanal endoscopic microsurgery procedure needs specific equipment to improve the surgery; however we could complete the surgical dissection using standard laparoscopic devices with articulated ones. The other factor makes single port surgery easier than transanal endoscopic microsurgery procedure is insufflation. It is easy and controlled way to be insufflated by a particular pump and cheaper than any insufflators. Furthermore, in the operating room, the patient's position on the table was not a limiting factor. As a conclusion, we report that for selected patients, single port surgery can be performed using a single incision laparoscopic surgical port as an adjusted surgical technique. It gives safe and feasible way to remove benign and malign polyps and tumors up to 20 cm in the rectum.  相似文献   
998.
The early and long-term results of polytetrafluoroethylene (PTFE) grafts in different anatomical locations were evaluated in 14 patients with Buerger's disease (thromboangiitis obliterans). During a 10-year period, 2160 patients with peripheral vascular disease were treated and, in 258, the diagnosis of Buerger's disease was made. Fourteen of these 258 patients underwent revascularization with PTFE grafts. In a follow-up period, up to 8 years patency rates were as follows: aorto/ilofemoral bypass 80%, femoropopliteal bypass 40%, femorocrural bypass 50% with a cumulative patency rate of 57.1%, and limb salvage rate of 88.9%. Because of the diverse nature and small number of the operations, the numerical results are not amenable to statistical analysis, but 88.9% limb salvage rate is satisfying in Buerger's disease. To the best of our knowledge, this is the first report on the use of PTFE grafts in Buerger's disease and it validates limb salvage even below the inguinal ligament.Presented at the 37th Annual World Congress, International College of Angiology, Helsinki, Finland, July 1995  相似文献   
999.
Pulmonary artery aneurysms (PAAs) are well known causes of mortality and morbidity in Beh?et disease (BD). However, pulmonary artery involvement in BD is not limited to PAA; the other main type of pulmonary artery involvement is pulmonary artery thrombus (PAT), with or without associated PAA. In addition, other types of lung disease like nodules and cavities in the lung parenchyma are frequently associated with pulmonary artery involvement, and can be misinterpreted as being due to infection. We surveyed the clinical, radiologic, and laboratory characteristics and outcome of 47 BD patients with pulmonary artery involvement and the associated findings, all seen and followed at a single dedicated tertiary care center.We identified 47 (41 male, 6 female) patients in whom pulmonary artery involvement was diagnosed, who were registered in the multidisciplinary clinic at Cerrahpasa Medical Faculty between January 2000 and December 2007. Mean age at diagnosis was 29 ± 8 years, and mean disease duration to the onset of pulmonary artery involvement was 3.6 ± 4.8 years. Hemoptysis was the most common presenting symptom (79%) followed by cough, fever, dyspnea, and pleuritic chest pain. Thirty-four of 47 patients (72%) presented with PAA, including 8 with associated PAT. The remaining 13 patients (28%) had isolated PAT. Patients with isolated PAT in general have clinical features similar to patients with PAA. However, hemoptysis was less frequent and voluminous in patients with isolated PAT. Most (91%) of the patients had active disease outside the lungs when they presented with pulmonary artery involvement.Forty (85%) patients had nodules and 6 (13%) had cavities when first seen. Peripheral venous thrombosis was present in 36 of 47 (77%) patients, and intracardiac thrombi in 12 of the 36 (33%) patients. Nodules, cavities, and intracardiac thrombi were mainly present in the acute stages of pulmonary artery involvement.Pulmonary artery involvement is usually multiple, and involves mostly descending branches of the pulmonary artery. Pulmonary artery involvement may disappear, but arterial stenosis or occlusions usually develop at the same location. After a mean follow-up of 7 years, 12 of 47 (26%) patients were dead; patients with larger aneurysms were more likely to die. Sixteen of 47 (34%) patients were symptom free, and the remaining 40% had mild dyspnea (13/47) and/or small bouts of hemoptysis (8/47).Pulmonary artery pressure may be elevated, and may indicate a poor prognosis. Mediastinal lymphadenopathy and mild pleural and pericardial effusions may also be observed. Corticosteroids and immunosuppressive agents are the mainstays of treatment; however, refractory cases may require embolization, lobectomy, cavitectomy, and decortication.  相似文献   
1000.
Cytomegalovirus (CMV) infection is usually asymptomatic in immunocompetent patients. A mononucleosis-like syndrome may develop in some patients. Various organ involvements (eg: encephalitis, meningitis, retinitis, myocarditis, pneumonia, hepatitis, enterocolitis, neuritis), which rarely occur in immunocompetent patients, have also been reported. Cutaneous necrotizing vasculitis caused by CMV infection has been reported very rarely in the literature. Here, a case with a very rare clinical form of CMV infection, presenting with persistent fever and livedo reticularis on the extremities and cutaneous necrotizing vasculitis of the toes, is described, and the relevant literature is reviewed. This case report aims to highlight the possibility of CMV infection to be a cause of cutaneous necrotizing vasculitis.  相似文献   
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