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1.
Purpose:It has been reported previously that intravenously administered gadolinium-based contrast agent (GBCA) leaks into the subarachnoid space around the cortical veins at 4 h after injection in all old people over 37 years, but not in younger people up to 37 years of age in 3D-real IR images. The purpose of this study was to investigate whether there was a strict threshold of 37 years of age for the leakage of the GBCA into the subarachnoid space.Methods:The subjects included 190 patients, that were scanned for 3D-real IR images at 4 hours after intravenous injection of GBCA as a diagnostic test for endolymphatic hydrops. The patient’s age ranged from 14 to 81 years. Two experienced neuroradiologists evaluated the images to determine whether the GBCA leakage around the cortical veins was positive or negative. Any discrepancies between the two observers were discussed and a consensus was obtained.A Mann–Whitney U test and receiver operating characteristic (ROC) curve analysis were used to compare the positive and the negative group and to set the age cut-off value for the prediction of GBCA leakage.Results:The GBCA leakage around the cortical veins was negative in 35 patients and positive in 155 patients. The average age was 33 ± 11 years in the negative group, and 55 ± 12 years in the positive group (P < 0.01). In the ROC analysis for the age and leakage of the GBCA, an area under the curve was 0.905 and the cut-off age was 37.317 years (sensitivity of 0.942 and specificity of 0.771).Conclusion:Intravenously administered GBCA leaks into the subarachnoid space around the cortical veins in most patients over 37 years of age. However, it should be noted that it can be found occasionally in patients under 37 years of age.  相似文献   
2.
Because spitzoid melanoma shares many histopathologic features with Spitz nevus, it is one of the most difficult lesions to diagnose in dermatopathology. Uncertainty exists in the medical literature about how to diagnose melanocytic proliferations including Spitz nevus and spitzoid melanoma. A misdiagnosis of a melanoma as Spitz nevus is one of the most frequent causes of malpractice lawsuits in surgical pathology and dermatopathology. This contribution provides a review of the clinical presentation, histopathology, ancillary studies, treatment, and the differential diagnosis of spitzoid melanoma.  相似文献   
3.
Background: Clonidine can effectively reduce pain and/or hypersensitivity. However, the antihypersensitivity effects of clonidine topically applied in cream (CC) have not been investigated. The authors evaluated effects of topical application of CC on pain behaviors and spinal Fos-like immunoreactivity in rats with hypersensitivity.

Methods: Clonidine (30, 100, and 300 [mu]g/g) was prepared in a cream base. In rat models of neuropathic pain, inflammatory pain, and postoperative pain, the authors evaluated effects of CC (0.1 g), topically applied onto the plantar surface of the injured or uninjured paw, on thermal hyperalgesia and mechanical allodynia to von Frey filaments. The authors also evaluated effects of CC on lumbar spinal Fos-like immunoreactivity.

Results: In neuropathic rats, CC applied onto the injured paw reduced thermal hyperalgesia and mechanical allodynia dose dependently, whereas CC applied onto the uninjured paw had no effect. The antihypersensitivity effects of CC were antagonized by intraperitoneal yohimbine (10 mg/kg). Further, CC reduced Fos-like immunoreactivity in neuropathic rats. In contrast, CC in a single dose had no effects on hyperalgesia, allodynia, or Fos-like immunoreactivity in rats with inflammatory or postoperative pain. In rats with postoperative pain, CC repeatedly applied for 6 days reduced thermal hyperalgesia, but not mechanical allodynia, in the postoperative days, whereas it had no effects on hyperalgesia or allodynia in those with inflammatory pain.  相似文献   

4.
Background and Objective: To investigate Photofrin® (PII) and CASPc for photodynamic therapy (PDT) of the ciliary body in rabbits. Study Design/Materials and Methods: PII (10 mg/kg) or CASPc (1 mg/kg) was given by ear vein. Pharmacokinetics were studied in frozen sections by fluorescence microscopy (CCD camera based low light detection system with digital image processing) at 1 and 24 h (8 rabbits;16 eyes). Laser light was delivered (argon pumped dye laser;630 and 675 nm;8 rabbits;16 eyes) by contact fiberoptic. To compensate for iris attenuation, irradiance was 125 mW/cm2 (20, 40, 80, or 160 J/cm2). Controls (4 rabbits;8 eyes) received laser light without photochemicals (OD) and for comparison, continuous wave Nd:YAG laser by fiberoptic (0.8–1.2J;OS). Results: Localization studies showed intravascular distribution with some selective ciliary body distribution at 24 h (PII > CASPc). Rabbits treated with PII or CASPc exhibited variable amounts of gross ciliary body edema, infarction, and necrosis by 24–48 h. This response was not seen in PDT control tissues;damage was seen in the iris and ciliary body, with partial vacuolization of the pigment epithelium. Conclusion: PDT may offer a more selective approach to ciliary body destruction. A small but significant thermal effect was seen during PDT from melanin photon uptake with damage to iris and ciliary body. Thermal damage and potential interaction with ocular visual pigments may limit use of these photochemicals and wavelengths for PDT of the ciliary body © 1995 Wiley-Liss, Inc.  相似文献   
5.
A case of Beh?et disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Beh?et disease.  相似文献   
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7.
A 63-year-old female, with a chief complaint of right chest pain was referred to our hospital because of an abnormal right chest wall shadow on chest X-ray. A rib tumor was suspected based on her chest CT scan. Percutaneous needle biopsy yielded a diagnosis of well-differentiated adenocarcinoma. As metastatic rib tumor was suspected, the primary tumor was sought for. A thyroid gland nodule was recognized by ultrasonography, and the cytological diagnosis was class V. Immunohistological demonstration of the thyroglobulin studies of the rib tumor tissue revealed papillary and trabecular patterns of cell arrangement and the presence of thyroglobulin existence. Definitive diagnosis of metastatic rib tumor from thyroid cancer was established. Immunohistological examination is useful to confirm the diagnosis of metastatic cancer of thyroid origin.  相似文献   
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9.
The effects of nilvadipine on the peripheral circulation in the lower extremities using a duplex system of two-dimensional colour and pulse Doppler ultrasonography were studied in 32 patients with type 2 diabetes mellitus and mild essential hypertension. The patients (19 men and 13 women) were randomly divided into treatment and control groups. The anatomical cross-sectional area and blood flow index of the dorsal pedis artery were determined by colour and pulse Doppler ultrasonography before and 60 min after administration of 4 mg nilvadipine or placebo. Pulse rate and blood pressure were measured simultaneously. There were no significant changes in pulse rate or blood pressure after administration of either drug. Both cross-sectional areas (from 4.3 +/- 0.4 to 5.2 +/- 0.5 mm2, p < 0.05) and blood flow index (from 40.3 +/- 4.3 to 58.8 +/- 9.0, p < 0.05) were significantly increased in the treatment group, whereas there were no significant changes in either measurement in the control group. The findings showed that a single administration of nilvadipine increases blood flow in the dorsal pedis arteries of diabetic patients.  相似文献   
10.
To evaluate the beneficial effects of heparin on flap survival area, an experimental study was carried out on dorsal flaps in rats. Topical applications of heparin, released from a silicone gel sheet onto the critical area (which generally necrosed without treatment), resulted in an increase in the flap survival area and rate as compared to controls (p < 0.01). When heparin was applied topically but solely to an area proximal to the critical area however, no increase in the survival area resulted.  相似文献   
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