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41.
To identify changes induced by chemotherapy in hepatic metastases, 34 patients with metastases underwent magnetic resonance (MR) imaging before the start of systemic chemotherapy and monthly thereafter. The number, size, and morphologic patterns of the lesions and changes in quantitative parameters (signal-to-noise ratio [S/N], contrast-to-noise ratio, and signal intensity ratio) were evaluated and correlated with response to treatment and prognosis. After treatment, seven patients showed a partial response, 18 had stable disease, and nine had progressive disease. No relevant changes in the patterns of the lesions were observed. Quantitative data showed that patients with a good prognosis had an increase in S/N on T1-weighted images and a relative decrease on T2-weighted images; patients with a poor prognosis showed a decrease in S/N on T1-weighted images and an increase on T2-weighted images. The differences between patient groups were significant for both T1- and T2- weighted images. This study demonstrates the value of MR imaging in follow-up of liver metastases and suggests the usefulness of quantitative MR imaging data.  相似文献   
42.
An increase has been observed not only in the absolute number of CT examinations but also in the length of coverage and number of scanning phases, with the result that exposure to ionising radiation from CT is becoming an increasingly serious problem. The extent of the problem is not entirely known and cannot be adequately addressed without proper knowledge of all the phases that leads to the effective dose calculation. In light of the growing awareness of the issue of ionising radiation dose and the possible risk for the individual and the population, there is a need for radiologists, medical physicists and radiographers to play an active role in dose management. In this review, the authors try to delineate the problem in a consequential and multifaceted way: radiation–patient interaction, possible mechanisms of damage, main CT dose units, risk and its quantification in the population, with the aim of optimising the acquisition dose without diagnostic drawbacks. For an “up-to-date” use of CT, radiologists must know the dose concerns for the single patient and population, and use the CT apparatus with the best dose care; substitute CT with other diagnostic techniques when possible, especially in children; reduce the number/extension of scans and phases, and the dose in single scans and single examinations.  相似文献   
43.
Hepatic portal venous gas is an uncommon clinical condition that is often characterized by acute onset of abdominal pain and is associated with a high rate of mortality despite clinical and/or surgical treatment. Radiologic diagnosis is important and usually includes abdominal radiography, ultrasound, and computed tomography. We describe the clinical, computed tomographic, and angiographic data of a patient with sigmoid diverticulitis who developed a massive embolism of the intra- and extrahepatic portal systems due to an enterovascular fistula and was treated with fistula embolization and subsequent sigmoidectomy.  相似文献   
44.
The purpose of this study was to evaluate MRI diagnostic accuracy in rheumatoid arthritis (RA), to compare MRI and radiological findings and to correlate these findings with the clinical and serological profile of the disease. The hands of 24 patients (20 females, 4 males) affected with typical RA (ARA criteria) were studied using a tomograph Magnetom 1.0 T Siemens. Two patients affected with RA refractory to conventional second-line drugs who received a bolus of methylprednisolone (1 g) were studied before and after such treatment. The hands of healthy volunteers were examined as controls. Besides MRI study all patients underwent: (1) radiological examination of the hands performed with a standard technique and (2) clinical and serological investigation aimed at characterizing diseases activity and extent. The radiographic and MRI findings were evaluated by two different observers who found 15 pathological elementary lesions and assigned a MRI and a radiological score to each patient. MRI exhibited significantly higher accuracy than radiography in evaluating rheumatoid soft-tissue changes and in detecting minimal skeletal lesions, while severe skeletal lesions were better detected by radiology. No correlation was found between pathological MRI findings, radiological results and clinical or serological data. A significant drop in soft-tissue effusion was observed after methylprednisolone pulse in two patients. This study confirms MRI potential in the study of rheumatoid joint lesions and in the early detection of minimal soft-tissue changes. Its use appears to be suitable for accurate monitoring of RA patients under specific therapy.  相似文献   
45.
The aim of this study was to compare unenhanced MRI, MnDPDP-enhanced MRI, and spiral CT in the detection of hepatic colorectal metastases. Forty-four patients with hepatic colorectal metastases were examined with unenhanced and MnDPDP-enhanced MRI and with unenhanced and contrast-enhanced spiral CT. The MR examination protocol included baseline T1-weighted spin-echo (SE), T1-weighted gradient-recalled-echo (GRE), and T2-weighted fast-SE sequences; and T1-weighted SE and T1-weighted GRE sequences obtained 30–60 min after administration of 0.5 µmol/kg (0.5 ml/kg) mangafodipir trisodium (MnDPDP). Images were interpreted by three blinded readers. Findings at CT and MRI were compared with those at intraoperative US, which were used as term of reference. Intraoperative US detected 128 metastases. In a lesion-by-lesion analysis, the overall detection rate was 71% (91 of 128) for spiral CT, 72% (92 of 128) for unenhanced MRI, and 90% (115 of 128) for MnDPDP-enhanced MRI. MnDPDP-enhanced MRI was more sensitive than either unenhanced MRI (p<0.0001) or spiral CT (p=0.0007). In a patient-by-patient analysis, agreement with gold standard was higher for MnDPDP-enhanced MRI (33 of 44 cases) than for spiral CT (22 of 44 cases, p=0.0023) and unenhanced MRI (21 of 44 cases, p=0.0013). MnDPDP-enhanced MRI is superior to unenhanced MRI and spiral CT in the detection of hepatic colorectal metastases.  相似文献   
46.

Objective

To investigate the efficacy of gadobenate dimeglumine (Gd-BOPTA) enhanced MR imaging for the detection of liver lesions in patients with primary malignant hepatic neoplasms.

Materials and Methods

Thirty-one patients with histologically proven primary malignancy of the liver were evaluated before and after administration of Gd-BOPTA at dose 0.05 or 0.10 mmol/kg. T1-weighted spin echo (T1W-SE) and gradient echo (T1W-GRE) images were evaluated for lesion number, location, size and confidence by three off-site independent reviewers and the findings were compared to reference standard imaging (intraoperative ultrasound, computed tomography during arterial portography or lipiodol computed tomography). Results were analyzed for significance using a two-sided McNemar''s test.

Results

More lesions were identified on Gd-BOPTA enhanced images than on unenhanced images and there was no significant difference in lesion detection between either concentration. The largest benefit was in detection of lesions under 1 cm in size (7 to 21, 9 to 15, 16 to 18 for reviewers A, B, C respectively). In 68% of the patients with more than one lesion, Gd-BOPTA increased the number of lesions detected.

Conclusion

Liver MR imaging after Gd-BOPTA increases the detection of liver lesions in patients with primary malignant hepatic neoplasm.  相似文献   
47.
Hepatic fatty infiltration generally appears in a widespread form but it can occasionally involve the liver in an irregular way. As regards focal forms, nodular focal fatty infiltration (NFFI) has great importance regarding problems of differential diagnosis with benign and malignant focal pathology of the liver. Except for this aspect, NFFI has little clinical importance as it is mainly asymptomatic. We report a case of an acute bleeding of a big nodule of FFI which required an urgent hepatectomy.  相似文献   
48.

Sarcopenia is characterized by loss of muscle mass, altered muscle composition, fat and fibrous tissue infiltration, and abnormal innervation, especially in older individuals with immune-mediated rheumatic diseases (IMRDs). Several techniques for measuring muscle mass, strength, and performance have emerged in recent decades. The portable dynamometer and gait speed represent the most frequently used tools for the evaluation of muscle strength and physical efficiency, respectively. Aside from dual-energy, X-ray, absorptiometry, and bioelectrical impedance analysis, ultrasound (US) and magnetic resonance imaging (MRI) techniques appear to have a potential role in evaluating muscle mass and composition. US and MRI have been shown to accurately identify sarcopenic biomarkers such as inflammation (edema), fatty infiltration (myosteatosis), alterations in muscle fibers, and muscular atrophy in patients with IMRDs. US is a low-cost, easy-to-use, and safe imaging method for assessing muscle mass, quality, architecture, and biomechanical function. This review summarizes the evidence for using US and MRI to assess sarcopenia.

  相似文献   
49.

Purpose

This paper analyses the methodological and technical aspects of health technology assessment (HTA) as a tool for evaluating health technologies and procedures, with special reference to diagnostic imaging; describes the main experiences with HTA at the international and national level; outlines the most important HTA projects in Italy, and analyses the effects of HTA on health care strategies and policies.

Materials and methods

The work was carried out in three phases. In the first phase, the authors analysed the principles, methods and instruments of HTA; in the second, they evaluated the current status of HTA in different countries; and in the third, they defined the impact of HTA on the decision-making process in health care.

Results

Since the 1970s, technological innovation has been accompanied by the development of methods for the multidisciplinary assessment of the technical, scientific, economic, ethical and social aspects inherent in the use of new technologies. The method is implemented at an international level by a network of public and private bodies that carry out HTA in support of health care policies.

Conclusions

Because the application of HTA is still in its early stages in Italy, it is necessary to promote its development by drawing on consolidated international experiences.  相似文献   
50.
Inflammopharmacology - To evaluate the effect of 4&nbsp;weeks of treatment with Janus kinase inhibitors (JAKis) on central sensitization (CS) and pain catastrophizing, and to determine the...  相似文献   
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