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71.
72.
PURPOSE: To evaluate the therapeutic effect of iodine-131-labeled metaiodobenzylguanidine (131I-MIBG) and unlabeled MIBG in patients with carcinoid tumor. MATERIALS AND METHODS: A therapeutic dose of 7.4 GBq (200 mCi) 131I-MIBG infused over 4 hours was administered to 30 patients with either carcinoid syndrome (n = 20) or tumor symptoms such as pain and fever due to carcinoid tumor (n = 10). In general, two courses were given, 6 weeks apart. Due to radioactivity, patients had to be isolated for 5 to 7 days. Subsequently, we studied the effect of unlabeled MIBG based on the possible pharmaceutic activity of MIBG and to avoid the isolation procedure. A doseescalation study of 8.5, 17, and 34 mg/m2 MIBG infused over 4 hours at 4-week intervals was performed in 20 patients with carcinoid syndrome who were not suitable for treatment with the radioactive compound. RESULTS: Following 131I-MIBG treatment, symptomatic responses were observed in 60% of patients (median duration, 8 months; maximum, 2 years). Side effects were mild and rapidly reversible in 16 patients, and were related to the isolation procedure in seven of these patients. Unlabeled MIBG resulted in symptomatic improvement in 60% of patients (median duration, 4.5 months). Side effects, which included changes in blood pressure, were mild and transient. Symptomatic responses were not accompanied by biochemical responses. CONCLUSION: Both MIBG treatment regimens were equally effective in the palliation of symptoms, but duration of response tended to be much longer with the radioactive compound. However, the unlabeled compound provided a simpler treatment, eg, in elderly patients and those in poor condition, without the need for isolation.  相似文献   
73.
Patients with cirrhosis of the liver have increased hepatic and gastrointestinal lymph flow that may contribute to the formation of ascites and pleural effusions. Increased lymph flow, which is due to postsinusoidal portal hypertension, causes a high rate of flow through the thoracic duct. Because of the high flow rates, disrupted lymphatic vessels in patients with cirrhosis of the liver may fail to close, a situation that results in chylous ascites, pleural effusions, or chylous fistulas. Chylous fistulas deplete proteins, fluid, and lymphocytes and thus lead to volume depletion and coagulopathy. Herein we describe an unusual case in which a high-output traumatic thoracic duct-cutaneous fistula developed in a patient with cirrhosis and led to volume depletion and coagulopathy. Correction of the portal hypertension with placement of a transjugular intrahepatic portosystemic shunt led to closure of the fistula and normalization of accompanying metabolic abnormalities.  相似文献   
74.
Recordings of multiunit sympathetic activity were made in muscle branches of the peroneal nerve in 22 healthy subjects at rest in recumbent position. Nerve activity was quantitated in terms of burst incidence (number of pulse synchronous sympathetic bursts per 100 heart beats or per min). In a separate session, 4-45 months later, blood was drawn from an antecubital vein for noradrenaline analysis. Both sympathetic activity and plasma concentrations of noradrenaline varied widely between subjects and both parameters increased with age. There was a significant positive correlation between a subject's level of sympathetic activity and his plasma concentration of noradrenaline. It is suggested that overflow of transmitter from sympathetic terminals in muscles contributes significantly to plasma levels of noradrenaline at rest.  相似文献   
75.
The murine L5178Y (LY) lymphoma sublines, LY-R (radiation resistant) and LY-S (radiation sensitive) display a difference in susceptibility to camptothecin (CPT): LY-S cells are less sensitive to killing by this inhibitor of topoisomerase I than LY-R cells. Post-treatment (CPT present until 3 h after irradiation) sensitizes only LY-S cells. In agreement with this, only in LY-S cells is the relative number of DNA-protein cross-links formed after treatment with CPT + X higher than expected for additivity of X-ray and CPT-induced damage. The pattern of changes in the labelling indices and cell cycle distribution in cells that underwent combined treatment is essentially like that seen for single-agent treatment: for LY-S cells like that for radiation, for LY-R cells like that for CPT. We found no direct relation between the patterns of cell cycle distributions and the enhancement of the lethal effect of X-irradiation by CPT post-treatment. The sublines are not markedly differentially sensitive to beta-lapachone, which modifies topoisomerase I activity, and not sensitized to X-rays by post-irradiation treatment with the drug.  相似文献   
76.
We have identified alterations in the responses of muscarinic and metabotropic receptors in rat hippocampus that persist for at least 15 days after central fluid percussion injury. This study compares the effect of lateral fluid percussion and central fluid percussion on these responses. Moderate injury was obtained by displacement and deformation of the brain within the closed cranial cavity using a fluid percussion device positioned either centrally or laterally. Carbachol and (+/-)-1-aminocyclopentane-trans-1,3-dicarboxylic acid (trans-ACPD)-stimulated polyphosphoinositide (PPI) hydrolysis was assayed in hippocampus from injured and sham-injured controls at 15 days following injury. At 15 days after central fluid percussion traumatic brain injury (TBI), the response to carbachol was enhanced by 30% and the response to trans-ACPD was enhanced by 75% compared to sham-injured animals. At 15 days after lateral fluid percussion TBI the response to trans-ACPD was enhanced by 40% both ipsilateral and contralateral to the side of injury. In contrast, the response to carbachol was enhanced by 29% contralateral to the side of injury but was diminished by 12% ipsilateral to the side of injury. Cresyl violet staining shows no hippocampal cell death after central fluid percussion injury or on the side contralateral to lateral fluid percussion injury but on the ipsilateral side cell death was identified in hippocampal area CA3. Thus, abnormal hippocampal cell signaling through the phosphoinositide pathway occurs in the absence of cell death and may contribute to cognitive impairment.  相似文献   
77.
78.
Happle syndrome is an X-linked dominant disorder with presumed lethality in hemizygous males; familial occurrence is rare. We describe a family with Happle syndrome affecting individuals in 3 generations. A man in this family is the first known male patient with Happle syndrome. He is severely affected; this may be due to his 47,XXY karyotype.  相似文献   
79.
Atrial natriuretic peptide (ANP) is produced and secreted by atrial cells. We measured calf capillary filtration rate with prolonged venous-occlusion plethysmography of supine healthy male subjects during pharmacologic infusion of ANP (48 pmol/kg/min for 15 min; n = 6) and during placebo infusion (n = 7). Results during infusions were compared to prior control measurements. ANP infusion increased plasma [ANP] from 30 +/- 4 to 2,568 +/- 595 pmol/l. Systemic hemoconcentration occurred during ANP infusion: mean hematocrit and plasma colloid osmotic pressure increased 4.6 and 11.3%, respectively, relative to preinfusion baseline values (p < 0.05). Mean calf filtration, however, was significantly reduced from 0.15 to 0.08 ml/100 ml/min with ANP. Heart rate increased 20% with ANP infusion, whereas blood pressure was unchanged. Calf conductance (blood flow/arterial pressure) and venous compliance were unaffected by ANP infusion. Placebo infusion had no effect relative to prior baseline control measurements. Although ANP induced systemic capillary filtration, in the calf, filtration was reduced with ANP. Therefore, pharmacologic ANP infusion enhances capillary filtration from the systemic circulation, perhaps at upper body or splanchnic sites or both, while having the opposite effect in the leg.  相似文献   
80.
Exposure to irradiation or chemotherapy as well as prolonged exposure to risk factors, such as alcohol and tobacco, may induce a second primary carcinoma of the oesophagus. To estimate the potential risk of previous treatment regimens, we performed a case-control study. In the Tumour Registry of The Netherlands Cancer Institute, from 1955, 27 cases of squamous cell carcinoma of the oesophagus were identified following treatment for malignant lymphoma (n = 11), breast cancer (n = 8) and lung cancer (n = 8). The median interval was 6.6 years (range 1-16). Preferably 3 controls from the same tumour registry were matched to each case on the basis of sex, age, primary tumour, location of primary treatment (academic or general hospital), calendar year at diagnosis of primary tumour and duration of follow-up. Clinical data and details of treatment were obtained from the medical records. In patients who had smoked for more than 5 years, there was a 3.2-fold increased risk of oesophageal carcinoma (P = 0.04); for those with a regular alcohol intake the relative risk was 3.3 (P = 0.01). There was no significant relationship between irradiation of the mediastinum and subsequent risk for oesophageal cancer. The number of chemotherapy-treated patients was too small to calculate the relative risk associated with cytostatic drugs. In conclusion, oesophageal cancer as second primary cancer is extremely rare. Risk factors include the well known abuse of alcohol and tobacco. No significant relationship with previous mediastinal irradiation could be demonstrated.  相似文献   
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