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1.
Adolescence is a vulnerable period for developing anxiety-related mental disorders such as post-traumatic stress disorder (PTSD), which requires a long-term course of therapy when a traumatic event has been experienced during childhood. However, the biological mechanism underlying these age-dependent characteristics remains unclear. In the present study, we used early adolescent, late adolescent and adult (4-, 8-, and 15-week old) male mice to examine age differences in fear memory, fear extinction, and spontaneous recovery of fear. We also measured the activation of extracellular signal-regulated kinase (ERK) 2 in the dorsal hippocampus (dHip) and the basolateral amygdala (BLA) following a spontaneous recovery test. Our major findings were as follows: (1) early adolescent and adult mice did not recover the fear response; only late adolescent mice recovered the fear response. (2) The ERK2 in the dHip was more activated after the spontaneous recovery test in late adolescent mice than in adult mice, and the ERK2 in the BLA was more activated after the spontaneous recovery test in adult mice than in late adolescent mice. These results suggest that there exists a unique period in which spontaneous recovery occurs and that these late adolescent behavioral signatures may be related to alteration in the ERK2 phosphorylation in the dHip and BLA.  相似文献   
2.
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging.  相似文献   
3.
Laparoscopic cholecystectomy and time-course changes in renal function   总被引:13,自引:3,他引:10  
Background: Recently, the retraction method has been used to reduce intraabdominal pressure (IAP) during laparoscopic surgery. The purpose of this study was to determine the serial changes in renal function during laparoscopic cholecystectomy (LC) using the retraction method. Methods: Urine output, effective renal plasma flow (ERPF), and glomerular filtration rate (GFR) were measured serially in seven patients who underwent LC with 12 mmHg pneumoperitoneum (High-IAP group) and five who underwent LC using the retraction method with 4 mmHg pneumoperitoneum (Low-IAP group). Results: Urine output, ERPF, and GFR were decreased during pneumoperitoneum in the High-IAP group, whereas no significant changes in any of these parameters were observed in the Low-IAP group. Conclusions: Our findings demonstrate that reduction of IAP to 4 mmHg using the retraction method prevents the transient renal dysfunction caused by prolonged 12 mmHg pneumoperitoneum during LC, suggesting that the retraction method reduces the risk of perioperative renal dysfunction during laparoscopic surgery. Received: 26 March 1996/Accepted: 27 July 1996  相似文献   
4.
Clinical effect of LM-001, a prostaglandin synthetic inhibitor developed from a drug delivery system, was evaluated in 54 patients with pain from urinary tract stones (stone pain) and 32 with vesical urgency after an operation on bladder or prostate. LM-001, felbinac ethyl incorporated in lipid microsphere, wes intravenously administered at the onset of stone pain or vesical urgency. Of 54 with stones and 32 with urgency, 53 and 29 were eligible for response, respectively. The symptoms improved or disappeared in some cases just after the administration and in the majority of patients within 15 minutes, in 49 of 53 patients with stone pain. Further, the effectiveness lasted over 24 hours in 26 of the 49 responding to this agent. On one hand, improvement or disappearance of vesical urgency was recognized in 25 of 29 patients, and the effectiveness was observed shortly after injection in 16 and lasted over 24 hours in 13 cases. Toxicities of this drug were investigated in 54 patients with stone pain and 32 with urinary urgency. Side effects consisted of pain at the injection site in 4, a slight fall of blood pressure in 1, slight visual disturbance in 1, body heat sensation in 1, leukocytosis in 3 and elevation of alkaline phosphatase in 1. These symptoms were transient and disappeared without use of any agent. LM-001 is concluded to be a useful drug for controlling stone pain and vesical urgency since an immediate effect, long durability and high response rates were obtained without severe side  相似文献   
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7.
Carnitine status in Reye and Reye-like syndromes   总被引:4,自引:0,他引:4  
Fourteen children with the following Reye and Reye-like syndromes were studied to determine each patient's carnitine status: valproate-induced Reye-like attack, ornithine transcarbamylase deficiency, systemic carnitine deficiency, methylmalonic acidemia, and propionic acidemia. Reduced free carnitine and increased serum and urine acylcarnitine levels were found in all patients except for 2 with Reye syndrome, in whom serum creatinine levels were mildly elevated and serum free carnitine levels were not reduced. The renal free carnitine reabsorption rate was reduced in all cases. The free carnitine content of autopsied liver samples were reduced in 2 Reye syndrome patients, 2 OTC deficiency patients, and in a single systemic carnitine deficiency patient. The observed secondary free carnitine deficiency may be a factor in the pathogenesis of Reye and Reye-like syndromes.  相似文献   
8.
Isolated ultrafiltration, hemodialysis & peritoneal dialysis (Tx) were recently used in the treatment of intractable heart failure (HF). We examined the relation between the response of HF to Tx and the residual kidney functions. Tx was carried out in 17 patients (Pts) with HF who did not respond to aggressive medical treatment. Ten Pts (R) responded to Tx and 7 Pts (N) did not. Serum urea nitrogen (UN), creatinine (Cr), uric acid (UA), sodium (Na), potassium (K), and chloride (Cl) concentrations on admission and before Tx were not different between R and N. Urine UN, Cr, Na, K, and Cl on admission and before Tx were also not significantly different. Fractional sodium excretions (FENa), renal failure indices (RFI), and urine/plasma Cr ratios (U/P Cr) on admission were 2.0 +/- 1.6, 2.7 +/- 2.2, and 30.5 +/- 20.0 in R and 5.9 +/- 4.2, 8.2 +/- 6.0 and 11.5 +/- 3.8 in N. They were significantly different (p less than 0.05). However, these did not differ before and after Tx. These data show that FENa, RFI and U/P Cr might be useful indices in predicting the responsiveness of intractable HF to Tx.  相似文献   
9.
Prolidase was highly purified from human liver and erythrocytes. NaDodSO4/acrylamide gel electrophoresis revealed that these preparations contained a major protein with MW = 56,000. The mass of prolidase was estimated on gel filtration to be MW = 97,000, for both enzyme preparations. A monoclonal antibody was raised against the liver enzyme and a specific antiserum against the erythrocyte enzyme. The monoclonal antibody (EP-2) recognized prolidase from erythrocytes and liver, in equal proportions. The antiserum also recognized the enzyme from erythrocytes and liver. Immunoprecipitation studies with these antibodies suggested only a single species of prolidase in erythrocytes and liver. Using an immobilized monoclonal antibody (EP-2) as an immunoadsorbent, prolidase was partially purified from crude extracts, and the protein of the partially purified enzyme was identified by immunoblotting using antiserum. A protein band with a MW = 56,000 was demonstrated specifically when crude extracts from the liver and erythrocytes were examined using NaDodSO4/acrylamide gel electrophoresis. The subunit protein was absent in erythrocytes from a patient with prolidase deficiency. We propose that the absence of the subunit is one cause of the prolidase deficiency.  相似文献   
10.
Using immunoaffinity chromatography, two species of apo-AI containing lipoproteins (AILp); lipoprotein containing apo-AI and apo-AII (Lp-AI/AII), and lipoprotein containing apo-AI, but no apo-AII (Lp-AI) were isolated from 13 female patients on continuous ambulatory peritoneal dialysis (CAPD), then characterized. The results were compared with findings obtained in agematched normolipidemic (control I) and mild hypertriglyceridemic (control II) female subjects. In comparison with control I: In AILp, the levels of total cholesterol (TC), cholesteryl ester (CE) and phospholipid (PL), and the levels of apoE were significantly lower in the CAPD patients while the levels of triglyceride (TG) and apo-CIII were significantly higher in these patients. The levels of apo-AI and apo-AII did not differ between the CAPD and control subjects. In Lp-AI/AII, changes of TC, CE, PL, TG, and apolipoproteins were similar to those of AILp, except for the ratio of apo-AI/apo-AII and the level of apo-CII, which was higher in the CAPD patients. In Lp-AI, changes of TC, CE, PL, and TG were also similar to those of AILp and Lp-AI/AII, but the apo-AI level was significantly lower in the CAPD patients. In comparison with control II: In AILp, the levels of PL, apo-AI, apo-AII, and apo-E were significantly lower in CAPD patients, but the apo-CIII levels were significantly higher. In Lp-AI/AII, the levels of PL and apo-E were significantly lower in CAPD patients.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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