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81.
The selective delivery of human recombinant interferon (IFN)- to isolated rat hepatocytes was studied with asialofetuin (AF)-labeled liposomes. AF-liposomes containing buffer solution were initially prepared by the detergent removal method, and IFN- was subsequently encapsulated by the freeze-thawing method without loss of activity. Virtually no free [32P]IFN- was internalized into isolated rat hepatocytes, whereas AF-liposomes containing [32P]IFN- were taken up to a significant degree. Liposomal binding to the hepatocytes (estimated at 4°C) was one-fifth of the uptake (estimated at 37°C). Since the uptake was inhibited by the addition of free AF, AF-liposomes may be taken up by the action of galactose-binding protein on the hepatocytic cell surface. The liposome preparation method reported in this paper provides a useful means for the encapsulation of unstable macromolecules into AF-liposomes. AF-liposomes were found effectively to carry IFN- into hepatocytes in vitro.  相似文献   
82.
Temperature changes and their distribution induced by 13.56-MHz radiofrequency (RF) heating of agar phantom and porcine and rabbit liver were investigated. It was possible to produce selective local heating of approximately 50 degrees C in the RF field of 2 x 2 x 2 cm(3) of the pig or rabbit liver. Coagulation necrosis after heating became pronounced and the margin between the coagulated lesion and normal tissue became clearer with time. Within 1 week after RF heating at 50 degrees C for 20 min, the coagulated area was replaced selectively and totally by necrotic tissue.  相似文献   
83.
OBJECTIVE: The purpose of this study is to evaluate the correlation between the intranodular blood supply revealed by CT during intraarterial injection of contrast medium, mainly using helical CT, and the grade of malignancy of hepatocellular nodules associated with liver cirrhosis as classified by the International Working Party of the World Congress of Gastroenterology. SUBJECTS AND METHODS: We studied 201 histologically proven nodules (101 resected and 100 biopsied nodules), including 47 low-grade dysplastic nodules (low-DNs), 56 high-grade dysplastic nodules (high-DNs), 24 well-differentiated hepatocellular carcinomas (wd-HCCs), and 74 moderately or poorly differentiated HCCs (mp-HCCs), in 139 cirrhotic patients. Findings on CT during arterial portography (n = 201) and CT during hepatic arteriography (n = 74) were reviewed and compared with the histologic diagnosis. RESULTS: CT findings were classified into four types relative to the surrounding liver: type A (isodense), type B (slightly hypodense), type C (partially hypodense), and type D (markedly hypodense) on CT during arterial portography and type I (isodense), type II (hypodense), type III (partially hyperdense), and type IV (hyperdense) on CT during hepatic arteriography. On CT during arterial portography, the distributions of each type were low-DN (n = 47 [A, n = 36; B, n = 8; C, n = 3]), high-DN (n = 56 [A, n = 18; B, n = 20; C, n = 10; D, n = 8]), wd-HCC (n = 24; [B, n = 4; C, n = 13; D, n = 7]), and mp-HCC (n = 74 [D, n = 74]). On CT during hepatic arteriography, the distributions were low-DN (n = 26 [I, n = 18; II, n = 7; III, n = 1]), high-DN (n = 19 [I, n = 6; II, n = 7; III, n = 4; IV, n = 2]), wd-HCC (n = 15 [I, n = 1; III, n = 8; IV, n = 6]), and mp-HCC (n = 14 [IV, n = 14]). We found a statistically significant correlation between the four types and the grade of malignancy of these nodules. CONCLUSION: Findings on CT during arterial portography and CT during hepatic arteriography correlated positively with histologic grading when overlap in appearance between dysplastic nodules and HCCs occurred. The concept revealed in this study can apply to diagnoses made on the basis of Doppler sonography, dynamic CT, and MR imaging.  相似文献   
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By using the microdialysis technique, the concentration of noradrenaline (NA) in the dorsal horn during unilateral hindpaw inflammation was compared between rats receiving bilateral lesions of the locus coeruleus (LC) and non-operated control rats. Bilateral lesions of the LC were made using an anodal current one week before testing. Unilateral hindpaw inflammation was produced by a subcutaneous injection of carrageenan (6 mg in 0.15 ml saline). Under conditions of sodium pentobarbital anesthesia, the microdialysis probe was inserted into the dorsal horn either ipsilateral or contralateral to the site of inflammation. The NA concentration in the dialysate was measured by high-performance liquid chromatography with electrochemical detection. Prior to carrageenan injection, the NA level (baseline level) did not differ between the LC-lesioned and the non-operated groups. After carrageenan injection, in the non-operated rats, the NA level increased significantly compared to the baseline level only in the dorsal horn ipsilateral to the site of inflammation, but not in the dorsal horn contralateral to the site of inflammation. An increase of the NA level was not observed in the LC-lesioned rats and in rats receiving an injection of saline. The result suggests that unilateral hindpaw inflammation produces excitation of descending NA-containing neurons from the LC, resulting in an increase of the NA level in the dorsal horn ipsilateral to the site of inflammation.  相似文献   
86.
This study sought to assess the prevalence and symptomatology of comorbid obsessive-compulsive disorder (OCD) among Japanese subjects who met the DSM-III-R criteria for bulimia nervosa (BN). The Structured Clinical Interview for DSM-III-R Patient Version was used to distinguish 26 BN patients with concurrent OCD from 52 BN patients without OCD. Obsessive-compulsive symptoms in BN subjects with concurrent OCD were evaluated using the Japanese version of the Yale-Brown Obsessive-Compulsive Scale. There were no differences in the prevalence of concurrent OCD between BN subjects with and without a lifetime history of anorexia nervosa. Among BN subjects with concurrent OCD, symptoms related to symmetry and order were most frequently identified, followed by contamination and aggressive obsessions, and checking and cleaning/washing compulsions. Bulimia nervosa subjects with concurrent OCD were more likely than subjects without OCD to have more severe mood and core eating disorder psychopathology. Comorbid OCD is a common phenomenon in Japanese bulimics (33%) similar to that suggested in BN subjects in the Western countries. Obsessive-compulsive symptoms related to symmetry and order were most frequently observed in BN subjects with concurrent OCD, which was a similar finding to that reported among restricting anorexic subjects.  相似文献   
87.
PURPOSE: The prognosis of metastatic renal cell carcinoma is extremely poor. In this type of metastatic tumor cytoreductive surgery of the primary tumor is often performed to confirm the histological type or improve the response to immunotherapy with agents such as interferon or interleukin-2. However, the timing and impact of cytoreductive surgery on the success of immunotherapy require further study. We determined the type of metastatic renal cell carcinoma for which cytoreductive surgery is beneficial. MATERIALS AND METHODS: We retrospectively reviewed the records of 58 patients in whom metastatic renal cell carcinoma was diagnosed at our hospital between 1986 and 1997. Three patients were excluded from study because they were judged to be poor candidates for surgery due to poor performance status. Of the remaining 55 patients 34 consented to cytoreductive surgery of the primary tumor and 21 did not. All except 1 patient were treated with interferon therapy. We evaluated the association of pretreatment serum C-reactive protein and the effect of surgery. RESULTS: We noted no significant difference in age at diagnosis, pretreatment serum immunosuppressive acidic protein, site of metastasis or performance status in 34 patients who underwent cytoreductive surgery and 21 who did not. Of the 21 patients in whom pretreatment serum C-reactive protein was within normal limits (less than 1.0 ng./ml.) no significant difference in disease specific survival was observed in those who did and did not undergo surgery (p = 0.4133). On the other hand, of 34 patients in whom pretreatment serum C-reactive protein was elevated (1.0 ng./ml. or greater) the prognosis was significantly better in those who did versus those who did not undergo surgery (p = 0.0054). Particularly the prognosis in patients in whom postoperative nadir C-reactive protein decreased to within normal limits was markedly better than in those in whom it remained elevated (p = 0.0025). CONCLUSIONS: Our study suggests that cytoreductive surgery is beneficial to patients in whom pretreatment serum C-reactive protein is elevated. Particularly, those in whom serum C-reactive protein decreases to within normal limits may expect longer survival when surgery is combined with postoperative immunotherapy. Currently to our knowledge the prognostic factor that predicts postoperative nadir C-reactive protein has not been identified, indicating that cytoreductive surgery of the primary tumor should be performed in patients with elevated pretreatment C-reactive protein and as performance status permits.  相似文献   
88.
We report a case of ductal carcinoma in situ (DCIS) of the breast detected by ultrasonographic mass screening in a 51-year-old woman. In a mass screening program for breast cancer, physical examination with inspection and palpation, and ultrasonography (US) were performed. A hypoechoic mass with a slightly irregular margin was detected by US in the lateral upper quadrant of the right breast, at a distance 2 cm from the edge of the nipple. The mass was not detected by physical examinations or by mammography (MMG). The mass, which measured 0.8 x 0.5 cm and was examined by fine needle aspiration biopsy (FNAB) under US guidance, was cytologically diagnosed as class X. Modified radical mastectomy (Auchincloss method) was performed with the patient's consent. Pathological examination of the resected specimen revealed DCIS (noncomedo type) and occult multiple foci of malignancy which was considered tracking centripetally underneath the nipple. This case suggests that US and FNAB performed under US guidance are useful in the detection and diagnosis, respectively, of a breast mass. We should take multifocality into consideration, particularly with tendency tracking to the nipple, in the treatment of small breast cancers such as DCIS.  相似文献   
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