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41.
ObjectiveTo investigate the presence of statistically significant geographical clusters of tuberculosis (TB) using Geographical Information System and spatial scan statistics in Dehradun, India.MethodsThe spatial scan statistic implemented with a software program, SaTScan v6.1, was used to test the presence of statistically significant spatial clusters of TB and to identify their approximate locations (P< 0.05 for primary clusters and P<0.1 for secondary clusters). Geographical Information System was used for geographical analysis.ResultsSignificant high rate spatial clusters were identified in seven wards of the Dehradun Municipal area.ConclusionsThere is sufficient evidence about the existence of statistically significant TB clusters in seven wards of Dehradun, India. The purely spatial scan statistics methodology used in this study has a potential use in surveillance of TB for detecting the true clusters of the disease.  相似文献   
42.
3D Computed Tomographic Angiography (CTA) is a noninvasive volumetric imaging technique increasingly used for evaluation of vascular system. The introduction of Multidetector CT (MDCT) has increased scanning speed, allowing shorter acquisition time, greater volume coverage and decreased contrast requirement while diminishing respiratory motion artifacts. Thin-slice collimation protocols are routinely used which generate isotropic 3D voxels that improve image quality. The ideal CTA study requires scanning at peak vascular enhancement for optimal opacification of arteries with separation of arteries and veins. MDCT has enabled complete lower extremity inflow and runoff studies with a single injection, as well as thin-section CTA covering the entirety of the Carotid arteries and Circle of Willis. Sixteen row MDCT has increased scanning speed further facilitating the development of novel applications such as coronary CTA. CTA when perfomed with MDCT offers a “one scan – many views” option useful in imaging vascular diseases. CTA has important advantages over conventional angiography, such as reduced risk, diminished time and better patient acceptance. With MDCT, 3D CTA is crossing vessel tortuosity and evaluation of vessel fragility.Key Words: Multidetector CT, CT angiography, Volume Rendering  相似文献   
43.

Background  

Since the 1980s the Majengo Observational Cohort Study (MOCS) has examined sexually transmitted infections, in particular HIV/AIDS, in a cohort of sex workers in Majengo, an impoverished urban village in Nairobi, Kenya. The MOCS investigators have faced criticism since the women have remained in the sex trade for the duration of their participation in the study, prompting concerns about exploitation. Yet despite these concerns, the cohort has survived for almost 30 years.  相似文献   
44.
AIM: To clarify the potential of delayed densitometry of late (fixed) contrast in differentiation between tumor and fibrosis in residual mediastinal lesion (RML). MATERIAL AND METHODS: Computed tomography (computed tomograph of the third generation COMATOM CR-3 made in Germany, SIEMENS) has examined 12 patients with mediastinal lymphosarcomas after polychemotherapy. All of them had a RML 3 to 6 cm in diameter. RESULTS: CT has detected 8 cases of the tumor and 4 cases of fibrosis. The criteria of the tumor were the following: increased RML density shortly after the contrast medium introduction and 30 min after urographine introduction (p < 0.01); RML density 30 min after introduction of contrast medium was higher than above the aorta (p < 0.01). Fibrosis in RML was stated if RML density before, at the high of concentration and after introduction of the contrast medium was the same (p > 0.01); aortic density was significantly higher of RML density at the height of the contrast (p < 0.01). CONCLUSION: The above method differentiates the tumor with fibrosis in RML with maximal probability. This facilitates further choice of therapeutic policy in secondary resistant form of primary mediastinal lymphosarcoma.  相似文献   
45.
Eukaryotic genomes possess an elaborate and dynamic higher-order structure within the limiting confines of the cell nucleus. Knowledge of the physical principles and the molecular machinery that govern the 3D organization of this structure and its regulation are key to understanding the relationship between genome structure and function. Elegant microscopy and chromosome conformation capture techniques supported by analysis based on polymer models are important steps in this direction. Here, we review results from these efforts and provide some additional insights that elucidate the relationship between structure and function at different hierarchical levels of genome organization.  相似文献   
46.

Background

The incidence of pseudoaneurysm has increased due to the large number of vascular procedures performed and the widespread use of anticoagulation therapy during procedures. Non-invasive methods for management of pseudoaneurysms comprise of ultrasound guided compression (USGC), thrombin therapy, arterial embolisation and endovascular stent graft insertion. We discuss our experience in the management of fourteen cases of pseudoaneurysms using non surgical techniques.

Methods

During a two year period, fourteen patients presenting with pseudoaneurysms of different regions were treated.

Result

Of the fourteen patients, eleven were iatrogenic and three were attributable to trauma. There were six cases of pseudoaneurysms of the femoral artery following coronary angiography studies. One patient developed pseudoaneurysm of right popliteal artery after external fixation of fracture right tibia and fibula. Three cases of renal artery pseudoaneurysms occurred following percutaneous nephrolithotomy (PCNL). The cases were evaluated using a varying combination of color doppler, multidetector computerised tomography (CT) and angiography. These cases were treated with ultrasound guided compression (USGC), stent graft and coil embolisation. The selection of method was based on the location and size of pseudoaneurysms besides the efficacy of the technique. USGC was performed in seven, of which six were in the femoral artery and one supraorbital. The technique was unsuccessful in three of the seven, wherein stent graft was deployed in the femoral artery. Coil embolisation was utilised in three cases of renal artery pseudoaneurysms following PCNL.

Conclusion

Follow up with color doppler and CT angiography within a week, 6 and 12 months period showed successful regression of pseudoaneurysms in all cases.Key Words: Pseudoaneurysm, Arterial trauma, Ultrasound guided compression, Coil embolisation, Endovascular stent graft  相似文献   
47.
Background: Proliferative vitreo-retinopathy (PVR) is the most common cause of failed repair of a primary rhegmatogenous retinal detachment (RRD). The success rates for the surgery of complicated RRD has doubled with improved vitreous techniques from 35-40% to approximately 65-75% at six months. However, despite these advances, recurrent vitreo-retinal traction leads to re-detachment in more than one-fourths of the initially successful cases. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. One focus has been on the use of intra-vitreal antimetabolites to prevent the occurrence of PVR.  相似文献   
48.
Background: The incidence of pseudoaneurysm has increased due to the large number of vascular procedures performed and the widespread use of anticoagulation therapy during procedures. Non-invasive methods for management of pseudoaneurysms comprise of ultrasound guided compression (USGC), thrombin therapy, arterial embolisation and endovascular stent graft insertion. We discuss our experience in the management of fourteen cases of pseudoaneurysms using non surgical techniques.  相似文献   
49.
Single photon emission computed tomography (SPECT) was performed in 31 patients with cerebral infarction and 13 who had had transient ischemic attacks, using iodine-123-labeled N,N,N'-trimethyl-N'-(2-hydroxyl-3-methyl-5-iodobenzyl)-1,3-propanediamin e (I-123-HIPDM) as the radiopharmaceutical. SPECT scans were compared with computed tomographic (CT) scans. SPECT was as sensitive as CT in detecting cerebral infarction (94% vs. 84%). The abnormalities were larger on the SPECT scans than on the CT scans in 19 cases, equal in seven, and smaller in five (SPECT abnormalities greater than or equal to CT abnormalities in 86% of cases). Fifteen of 30 patients with hemispheric infarction had decreased perfusion (decreased uptake of I-123-HIPDM) to the cerebellar hemisphere contralateral to the cerebral hemisphere involved by the infarction (crossed cerebellar diaschisis). Nine of these 15 patients had major motor deficits, while only one of the 15 without crossed cerebellar diaschisis had a major motor deficit.  相似文献   
50.
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