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11.
BACKGROUND: Interferon-gamma, produced by T-helper cells, activates macrophages and increases expression of major histocompatibility complex (MHC) products in acute and chronic rejection. We investigated the role of interferon-gamma in murine heterotopic tracheal allografts. METHODS: Tracheas from BALB/c mice were heterotopically transplanted to BALB/c (12 isografts: 2 weeks [n = 6] and 4 weeks [n = 6], C57BL/6 (12 allografts: 2 weeks [n = 6] and 4 weeks [n = 6]) and C57BL/6 interferon-gamma knockout mice (12 interferon-gamma knockout allografts: 2 weeks [n = 4] and 4 weeks [n = 8]). BALB/c interferon-gamma knockout tracheas were transplanted to C57BL/6 mice (reverse knockout: 4 weeks [n = 6]) and BALB/c interferon-gamma knockout mice (4 weeks [n = 2]). C57BL/6 tracheas were transplanted to Bm12 mice (MHC Class II mismatch allografts: 4 weeks [n = 6]). Conventional histology and immunohistochemistry for CD4, CD8 and CD11b were performed. RESULTS: Minimal (<20%) obliteration was seen at 2 weeks in the allograft groups. No obliteration was seen in the isograft groups. However, all allografts were completely obliterated at 4 weeks. Interferon-gamma knockout allograft combinations displayed severe rejection characterized by intense intra- and extraluminal infiltration by CD4-, CD8- and CD11b-labeled cells. The MHC Class II mismatch allograft group showed normal epithelium and mild sub-epithelial infiltration by CD4+ cells at 4 weeks (CD8-, CD11b-). CONCLUSIONS: Absence of interferon-gamma does not protect the allograft from obliteration. Epithelial destruction by cytotoxic T cells appears to be an important mechanism in the development of obliteration in murine heterotopic tracheal allografts.  相似文献   
12.
13.
AIM: To evaluate the effects of oral continuous 17beta-estradiol plus norethisterone acetate (E2/NETA) replacement therapy on abdominal subcutaneous fat, serum leptin level (SLL) and body composition in postmenopausal women. MATERIALS AND METHODS: A 6-month, prospective, randomized, double-blind and placebo-controlled study was conducted. Forty-three healthy naturally postmenopausal women aged 43-65 years were randomly assigned to receive E2/NETA (2 mg E2 plus 1 mg NETA, n = 22) or placebo (n = 21). Fasting SLL by enzyme-linked immunosorbent assay, subcutaneous abdominal fat thickness (STh) by ultrasound and the anthropometric indices of body weight (BW), body mass index (BMI), waist and hip circumference (WC, HC) and waist-to-hip ratio (WHR) were recorded at the beginning and the end of the study. RESULTS: After 6 months of therapy, BW and SLL increased in the placebo group (p = 0.043 and 0.033, respectively). WC, HC and STh decreased significantly in the E2/NETA group (p = 0.002, 0.006 and 0.000, respectively) and they were also significantly lower in women receiving E2/NETA than in women taking placebo (p = 0.000, 0.034 and 0.000, respectively). At baseline, SLL and STh were positively correlated with all anthropometric indices except WHR. CONCLUSION: Oral continuous combined regimen of E2/NETA significantly reduced central fat accumulation as assessed by WC and STh, and attenuated the increase in SLL. The observed changes in SLL were highly and positively related to changes in STh. The oral continuous combined E2/NETA regimen appears to have protective effects on cardiovascular function and probably on metabolic diseases by its slimming effect upon WC in postmenopausal women.  相似文献   
14.
BACKGROUND: Superficial lymphatic malformations are predominantly developmental malformations of infancy, but they may arise at any age. OBJECTIVE: To describe a patient with a late-onset superficial lymphatic malformation. METHODS: Case report and literature review. RESULTS: A 53-year-old woman was evaluated for a colored lesion that developed spontaneously on the anterior abdominal wall. The lesion was treated by surgical excision. Findings on histopathologic examination of the specimen were consistent with superficial lymphatic malformation. There was no recurrence of the lesion at 4 months after the operation. CONCLUSION: Superficial lymphatic malformations can develop in adults spontaneously without the presence of any predisposing condition. Because the majority of such late-onset malformations reported in the literature are localized lesions similar to the one in our patient, surgical removal with inclusion of subcutaneous tissue usually results in cure without recurrence.  相似文献   
15.
Intravenous Pyogenic Granuloma of the Hand   总被引:1,自引:0,他引:1  
BACKGROUND: Intravenous pyogenic granuloma is the intravasal counterpart of cutaneous pyogenic granuloma. This rare, benign lesion appears clinically as a subcutaneous nodule usually located in the upper extremity or neck in middle-aged people. It is hard to make an exact diagnosis on clinical basis, and there is a risk of recurrence because of undertreatment. OBJECTIVE: To report a case of an intravenous pyogenic granuloma located in the hand and to describe the clinical and histopathologic features of this rare vascular tumor. METHODS: An operation was performed on a 58-year-old female who presented with a small, painless mass in the right palm, and the pathologic examination revealed an intravenous pyogenic granuloma. CONCLUSION: This rare lesion should be differentiated from a regular pyogenic granuloma and should be excised with the vein segment to avoid recurrence.  相似文献   
16.
Methods: Second primary cancers constitute approximately 9–10% of malignancies diagnosed in the United States. We aimed to show the risk and incidance of second primary tumor occuring associated to urologic tumors and show the distrubution of tumors in Tracia region. We retrospectively examined the patients' files with the diagnosis of malignant disease between the years 1985–2000. Hazard function analysis was performed to estimate the relative risk of secondary malignancy occuring. Age, sex and tumor number were examined to find out if they affect on mortality rate. Results: A total number of 25 MPMNs were diagnosed. In 52 percent of the cases the second primary neoplasm developed within six months. The relative risk of development of a second neoplasm is found as increasing 1.111 times per month. The incidence of secondary malignancy occuring in the patients with one tumor was found as 6.31%. Age (p < 0.001) and tumor number (p < 0.001) are found as statistically effective predictor on mortality rate where the sex is not. Conclusions: In the patients with a primary tumor not only the metastasis must be investigated but also second primary tumors should be taken in to consideration. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
17.
Neuroleptic malignant syndrome (NMS) is the rarest and most serious of the neuroleptic-induced movement disorders. We describe a case of neuroleptic malignant syndrome (NMS) associated with the use of ziprasidone. Although conventional neuroleptics are more frequently associated with NMS, atypical antipsychotic drugs like ziprasidone may also be a cause. The patient is a 24-year-old male with a history of schizophrenia who developed signs and symptoms of NMS after 2 days of treatment with an 80-mg/day dose of orally administrated ziprasidone. This case is the earliest (second day of treatment) NMS due to ziprasidone reported in the literature.  相似文献   
18.
We investigated the effects of activated protein C resistance (APCR), Factor V Leiden (FVL) mutation, and high lipoprotein (a) levels in 32 young patients with branch retinal vein occlusion (BRVO) vs 30 controls. No difference between patients with BRVO and controls was found with regard to APCR, FVL mutation, or lipoprotein (a) levels. These factors do not seem important in the etiology of BRVO. The authors have stated that they do not have a significant financial interest or other relationship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
19.
Because chronic Mycoplasma pneumoniae respiratory infection is hypothesized to play a role in asthma, the potential of M. pneumoniae to establish chronic respiratory infection with associated pulmonary disease was investigated in a murine model. BALB/c mice were intranasally inoculated once with M. pneumoniae and examined at 109, 150, 245, 368, and 530 days postinoculation. M. pneumoniae was detected in bronchoalveolar lavage fluid by culture or PCR in 70 and 22% of mice at 109 and 530 days postinoculation, respectively. Lung histopathology was normal up to 368 days postinoculation. At 530 days, however, 78% of the mice inoculated with M. pneumoniae demonstrated abnormal histopathology characterized by peribronchial and perivascular mononuclear infiltrates. A mean histopathologic score (HPS) at 530 days of 5.1 was significantly greater (P < 0.01) than that for controls (HPS score of 0). Serum anti-M. pneumoniae immunoglobulin G was detectable in all of the mice inoculated with M. pneumoniae and was inversely correlated with HPS (r = -0.95, P = 0.01) at 530 days postinoculation. Unrestrained whole-body plethysmography measurement of enhanced pause revealed significantly elevated airway methacholine reactivity in M. pneumoniae-inoculated mice compared with that in controls at 245 days (P = 0.03) and increased airway obstruction at 530 days (P = 0.01). Murine M. pneumoniae respiratory infection can lead to chronic pulmonary disease characterized by airway hyperreactivity, airway obstruction, and histologic inflammation.  相似文献   
20.
100 cases of either sex 96 males and 4 females in their mean age group of 45 year ± 14.51 standard deviation were selected for this study to analyse the Hearing Acuity in the post spinal analgesia period during a period of eight months in the E.N.T department of the J.N. Medical College A.M.U. Aligarh. The size of the needle used for spinal analgesia was 22G and the equipment for Audiometry was the pure tone Audiometer. Pure tone Audiometry was done pre-operatively and then on the 1st, 3rd, 5th and 12th subsequent post-operative days and then after six months. It was found that 12% of the patients showed incidence of mild hearing loss. However, the loss was transient, reversible, within low frequency range (250, 500, 1000 Hz), and no patient suffered from any permanent hearing loss.  相似文献   
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