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31.
Purpose: The aim of the study was to determine the impact of cataract on the quantitative, non‐invasive assessment of retinal blood flow assessed by bidirectional laser Doppler flowmetry and simultaneous vessel densitometry. Methodology: Ten patients scheduled for extracapsular cataract extraction using phacoemulsification and intraocular lens implantation between the ages of 61 and 84 (mean age 73 years, SD ± 8) were prospectively recruited. Two visits were required to complete the study; one visit prior to extracapsular cataract extraction and one at least 6 weeks after the surgery to allow for sufficient postoperative recovery. The severity of cataract was documented using the Lens Opacity Classification System (LOCS, III) at the first visit. Retinal arteriolar hemodynamics were measured at both visits using the high‐intensity setting of the Canon Laser Blood Flowmeter. Results: All eyes showed no clinical signs of postoperative intraocular inflammation. The quantitative assessment of retinal arteriolar diameter and blood flow were reduced following extracapsular cataract extraction (Wilcoxon signed‐rank test, p = 0.022 and p = 0.028, respectively); however, centreline blood velocity was not significantly changed (Wilcoxon signed‐rank test, p = 0.074). Intraocular pressure was unchanged pre‐ and postcataract extraction. Conclusions: Retinal vessel densitometry assessment in the presence of cataract results in the erroneous elevation of the diameter measurement and thereby the calculation of blood flow. The bidirectional Doppler assessment of blood velocity appears to be more robust to light scatter induced by cataract. Care needs to be exercised in the interpretation of studies of retinal vessel diameter or blood flow that utilize similar densitometry techniques.  相似文献   
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We report a case of successful treatment of a high, stable intertrochanteric fracture (type 1) in a 59-year-old man. He sustained the injury 8 years after the resurfacing procedure. The fracture was fixed using three 6.5-mm cannulated screws, and he has returned to his normal level of activities 8 months after the fixation. We have shown that fixation with cannulated screws may be an acceptable option for treatment of high trochanteric fractures where a stable anatomical reduction can be obtained. We have also included a review of the literature for other reported surgical treatment options of this complication.  相似文献   
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Purpose: Antimicrobial activities of meropenem products on Klebsiella pneumoniae isolates were determined. Methods: 212 non-duplicated Klebsiella pneumoniae isolates were examined for in vitro meropenem susceptibility test by using the following disks, which were made from Meronem (AstraZeneca, UK), Exipenem (Exir, Iran) and Meroxan (DAANA, Iran) powders. MIC50 and MIC90 for meropenem antibiotics were determined.Results: Meronem had good activities against most isolates of Klebsiella pneumoniae, and only a few strains had a rather high MIC. Exipenem and Meroxan showed a similar activity with Meronem. Conclusion: Regarding the comparison of two internal generic meropenem products with the external Meronem product have shown that they are equivalents in terms of microbiological activity, as measured using the disk diffusion and MIC. In developing countries, we suggested preparing disks with antibiotic powders that can be an equivalent function in microbiological activity with standard disks. In addition, since it demonstrated significant antimicrobial activity against the Klebsiella pneumoniae. For use of Exipenem and Meroxan in vivo, it would be better to perform additional testing (activity against different species, stability etc.).  相似文献   
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Echocardiographic Findings of Patients With Retinal Ischemia or Embolism   总被引:2,自引:0,他引:2  
BACKGROUND AND PURPOSE: A potential source of emboli is not detected in more than 50% of patients with retinal arterial occlusive events. Echocardiographic studies are not always included in the diagnostic workup of these patients. The authors studied the diagnostic yield of transthoracic (TTE) and/or transesophageal (TEE) echocardiography in identifying potential sources of emboli in patients with retinal ischemia or embolism. METHODS: In a prospective study, 73 consecutive patients with clinically diagnosed retinal ischemia or embolism received a standardized diagnostic workup including retinal photography, echocardiography, and imaging studies of the internal carotid arteries. TTE was performed in 83.6% of patients, TEE was performed in 5.5% of patients, and both TTE and TEE were performed in 11.0% of patients. Ophthalmological diagnoses consisted of amaurosis fugax (n = 28), asymptomatic cholesterol embolism to the retina (n = 34), and branch or central retinal artery occlusion (n = 11). RESULTS: Echocardiography identified a potential cardiac or proximal aortic source for embolism in 16 of 73 (21.9%) patients, including 8 who also had either atrial fibrillation or internal carotid artery stenosis of more than 50% on the side of interest. Thus, 8 of 73 (11.0%) patients had lesions detected only by echocardiography. The most commonly identified lesions were proximal aortic plaque of more than 4 mm thickness (n = 7, 9.6%) and left ventricular ejection fraction of less than 30% (n = 6, 8.2%). TEE was particularly helpful in identifying prominent aortic plaques. CONCLUSION: Echocardiography frequently identifies lesions of the heart or aortic arch that can act as potential sources for retinal ischemia or embolism. Further studies are needed to evaluate the prognostic and therapeutic relevance of these findings.  相似文献   
36.
OBJECTIVES: We tested the hypothesis that gene therapy using apolipoprotein A-I Milano (apoA-IMilano) is more effective than that using wild-type apolipoprotein A-I (apoA-I) in reducing atherosclerosis. BACKGROUND: Apolipoprotein A-I Milano is a naturally occurring mutant with established antiatherogenic activity; however, its relative antiatherogenic efficacy compared with that of wild-type apoA-I remains unclear. METHODS: We performed bone marrow transplantation in female double-knockout mice lacking both the apoE and apoA-I genes using male donor mice-derived bone marrow that had been transduced with a retroviral vector alone or retroviral vector expressing wild-type apoA-I or apoA-IMilano gene under the control of macrophage-specific scavenger receptor A promoter. Mice were fed a high-cholesterol diet and killed 24 weeks after transplantation, at which time the extent of aortic atherosclerosis was determined. RESULTS: Compared with vector control (n = 12), apoA-IMilano gene therapy (n = 15) reduced aortic atherosclerosis by 65% (p < 0.001) and plaque macrophage immunoreactivity by 58% (p < 0.0001), whereas wild-type apoA-I (n = 11) reduced atherosclerosis by 25% (p = 0.1) and plaque macrophage immunoreactivity by 23% (p < 0.05). The apoA-IMilano gene therapy was significantly more effective in reducing atherosclerosis (p < 0.05) and macrophage immunoreactivity (p < 0.001) compared with wild-type apoA-I. The circulating levels of cholesterol, lipoprotein profile, and apoA-IMilano or wild-type apoA-I were comparable among the groups. Apolipoprotein A-I Milano was more effective than wild-type apoA-I in promoting macrophage cholesterol efflux. CONCLUSIONS: Macrophage-specific expression of the apoA-IMilano gene is more effective than wild-type apoA-I in reducing atherosclerosis and plaque inflammation despite comparable circulating levels of the transgene and lipid profile.  相似文献   
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The objective of the present study was to investigate the concentration of metals (cadmium, lead, chromium, zinc, copper, and iron) were measured in groundwater at 30 sites from the Birjand flood plain of eastern Iran during the November 2010; identify any relationships between metals and pH, total hardness. Metal concentrations in the groundwater samples were decreased in sequence of Zn > Fe > Cu > Cr > Pb > Cd, respectively. The results showed that the overall mean concentrations of Cd, Pb, and Cr were at 0.000, 0.023, and 0.049 mg l−1, respectively. The mean concentration of Cu, Zn, and Fe were 0.109, 0.192, and 0.174 mg l−1, respectively. Results also indicated that there were correlations among Cd, Cu, and Zn metals.  相似文献   
40.
The causes of many sporadic diseases are unexplained; the contribution of recessive loci with reduced penetrance is one possibility that has been difficult to explore. We describe an approach to this problem by first searching for diseases with higher prevalence in populations with high rates of consanguinity, then determining whether disease cases are more commonly the product of consanguinous union than controls in such populations, followed by analysis of genetic linkage in consanguinous cases. We demonstrate the utility of this approach by investigation of congenital heart disease in Iran. We found that patent ductus arteriosus (PDA), a common congenital heart disease, accounts for a higher fraction of congenital heart disease in Iran (15%) than in the United States (2-7%). Moreover, Iranian PDA cases demonstrated a marked increase of parental consanguinity (63%), compared with the general Iranian population (25%) or control cases with tetralogy of Fallot (30%). The recurrence of PDA among siblings was 5%. A genomewide analysis of linkage in 21 unrelated consanguinous PDA cases demonstrated a multipoint logarithm of odds score of 6.27 in favor of linkage of PDA to a 3-centimorgan interval of chromosome 12q24, with 53% of kindreds linked. These findings together establish a recessive component to PDA and implicate a single locus, PDA1, in one third or more of all PDA cases in Iran; they further suggest a role for this locus in PDA worldwide. Finally, these results suggest a general approach to the identification of recessive contributions to sporadic diseases.  相似文献   
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