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21.
Reconstructive methods following pancreaticoduodenectomy in our department are discussed and evaluated in this study. Between January 1980 and November 1990 fifty-two consecutive patients underwent pancreaticoduodenectomy because of pancreas head disease. Thirty-one patients underwent pancreaticojejunostomy and twenty-one had pancreaticogastrostomy as reconstructive procedures. Mortality rate was 6% in pancreaticojejunstomy versus zero in pancreaticogastrostomy. Six patients had leakage from the pancreaticojejunostomy, but only one patient had necrosis of the gastric stump and leakage from the pancreaticogastrostomy. This case had previous distal gastrectomy done for gastric ulcer. The residual stomach might not have been large enough, and the blood supply of the gastric stump might not have been adequate for pancreaticogastrostomy. Except for this case, none was observed with leakage from the pancreatic anastomosis in the pancreaticogastrostomy group. No statistical significance in operating time or blood loss was observed between the two methods. The pancreaticogastrostomy cases without complications had significantly less loss of body weight than those with pancreaticojejunostomy at the date of discharge (p < 0.05). It is concluded that pancreaticogastrostomy is the safer reconstructive method following pancreaticoduodenectomy, although it may not be indicated in patients with prior gastrectomy.  相似文献   
22.
CONTEXT: Mouse knockout models have clearly demonstrated the critical importance of IGF-I and IGF receptor type 1 (IGF-IR) for embryonic growth as well as postnatal growth. OBJECTIVE: We hypothesized that mutations of IGF-IR gene might predispose to short stature in children born with intrauterine growth retardation (IUGR). PATIENTS: Twenty-four children with unexplained IUGR (birth weight < -1.5 SD) and short stature (<-2.0 SD) were screened for abnormalities of the IGF-IR gene. METHODS: Direct DNA sequencing was used to identify IGF-IR gene mutations. Unprocessed IGF-IR proreceptor in fibroblasts was detected by immunoblot analysis. Functions of mutated IGF-IR in fibroblasts were evaluated by IGF-I binding, and IGF-I-stimulated DNA synthesis and beta-subunit autophosphorylation. RESULTS: We found the following results: 1) a heterozygous mutation (R709Q) changing the cleavage site from Arg-Lys-Arg-Arg to Arg-Lys-Gln-Arg was identified in a 6-yr-old Japanese girl (case 1) and her mother who also had IUGR with short stature (case 2); 2) fibroblasts from case 2 contained more IGF-IR proreceptor protein (189 +/- 26% of normal) and less mature beta-subunit protein (63 +/- 12%); 3) [125I]IGF-I binding to fibroblasts from case 2 was reduced, compared with normal control (0.61 +/- 0.16 x 10(6) vs. 1.14 +/- 0.12 x 10(6) sites per cell; P < 0.05); and 4) both IGF-I-stimulated [3H]thymidine incorporation and IGF-IR beta-subunit autophosphorylation were low in fibroblasts from case 2, compared with those of control (P < 0.05). CONCLUSIONS: These findings strongly suggest that this mutation leads to failure of processing of the IGF-IR proreceptor to mature IGF-IR and causes short stature and IUGR.  相似文献   
23.
Four new briarane-type diterpenoids, brianodins A-D ( 1- 4), were isolated from a soft coral, Pachyclavularia sp., and the structures and relative stereochemistry of 1- 4 were elucidated on the basis of spectroscopic data. The absolute configurations of 3 and 4 were assigned by the MTPA method. Brianodin A ( 1) showed a modest cytotoxicity.  相似文献   
24.
BACKGROUND: Although Bcl-2 is well known to have anti-apoptotic activities in vitro and in vivo, the role of Bcl-2 relating to liver regeneration remains controversial. The aim of this study was to document the effect of Bcl-2 expression on liver regeneration in rats undergoing a partial hepatectomy. MATERIAL AND METHODS: Adult male Wistar rats (n = 4/group) at 72 h before undergoing a 70% partial hepatectomy (PH) were administered 1 x 10(9) plaque-forming units of adenovirus vector encoding either human Bcl-2 (group 1) or LacZ (group 2) intravenously and were sacrificed at 0, 12 h, and at 1, 2, 3, 7, 14, and 21 days postoperatively. In group 3, normal saline was injected instead of adenovirus vector. Liver regeneration was monitored by measuring the restituted liver mass and proliferating cell nuclear antigen (PCNA) immunostaining. The incidence of apoptosis in the liver was analyzed by the immunohistochemical detection of single-stranded DNA at 14 and 21 days postoperatively. RESULTS: The restituted liver mass showed significantly higher values in group 1 (26.1 +/- 7.2%) than in group 2 (14.7 +/- 6.8%) and 3 (13.6 +/- 5.0%) at 1 day after PH (P < 0.05). The PCNA labeling index was significantly higher in group 1 (47.2 +/- 9.9%) than in groups 2 (19.0 +/- 7.8%) and 3 (19.2 +/- 15.2%) at 1 day after a partial hepatectomy (P < 0.05). The hepatocyte growth factor (HGF) mRNA expression was significantly lower in group 1 than in group 2 at 12 h after PH (P < 0.05). The number of single-stranded DNA-positive cells decreased significantly more in group 1 (5.67 +/- 1.53 positive cells/10 fields per tissue) than those in group 2 (18.33 +/- 7.57 positive cells/10 fields per tissue) at 14 days after PH. CONCLUSIONS: These results thus indicated that an overexpression of anti-apoptotic protein Bcl-2 does not necessarily have an anti-apoptotic effect on liver regeneration but appears to have a pro-proliferative effect in the early phase of liver regeneration.  相似文献   
25.
Administration of galanin-like peptide (GALP) leads to a decrease in both total food intake and body weight 24 h after injection, compared to controls. Moreover, GALP induces an increase in core body temperature. To elucidate the mechanism by which GALP exerts its effect on energy homeostasis, urethane-anesthetized rats were intracerebroventricularly injected with GALP or saline, after which oxygen consumption, heart rate, and body temperature were monitored for 4 h. In some cases, animals were also pretreated with the cyclooxygenase (COX) inhibitor, diclofenac, via intracerebroventricular (i.c.v.) or intravenous (i.v.) injection. c-Fos expression in the brain was also examined after injection of GALP, and the levels of COX and prostaglandin E2 synthetase (PGES) mRNA in primary cultured astrocytes treated with GALP were analyzed by using qPCR. The i.c.v. injection of GALP caused biphasic thermogenesis, an effect which could be blocked by pretreatment with centrally (i.c.v.), but not peripherally (i.v.) administered diclofenac. c-Fos immunoreactivity was observed in astrocytes in the periventricular zone of the third ventricle. GALP treatment also increased COX-2 and cytosolic PGES, but not COX-1, microsomal PGES-1, or microsomal PGES-2 mRNA levels in cultured astrocytes. We, therefore, suggest that GALP elicits thermogenesis via a prostaglandin E2-mediated pathway in astrocytes of the central nervous system.  相似文献   
26.
Reconstruction of the obliterated vesicourethral junction is both complex and difficult. Here, we report an innovative method using a mobilized bulbar urethra as a continent valve. Three patients with major problems at the vesicourethral junction underwent continent valve reconstruction. In cases 1 and 2, in which there were problems at the anastomosing site after radical prostatectomy, the bladder wall was closed, wedge resection of the midline pubic bone was performed, and a fully mobilized bulbar urethra was implanted submucosally into the anterior bladder wall. In case 2, augmentation cystoplasty using an ileal segment was required due to the small capacity of the bladder. In case 3, in which there was posterior urethra disruption associated with pelvic fracture, the bulbar urethra was implanted into the bladder wall in the same manner as in cases 1 and 2 without pubectomy. The postoperative follow‐up periods were 48, 36, and 12 months, respectively. In all patients, urinary management was achieved by self‐catheterization postoperatively, and the patients were satisfied with their status. This newly devised continent valve construction using a bulbar urethra is effective for reconstruction of the obliterated vesicourethral junction, which markedly improves patients' quality of life.  相似文献   
27.
We studied the activities of clarithromycin and fluoroquinolones (gatifloxacin, sitafloxacin, levofloxacin) in combination with other antimycobacterial drugs against extracellular and intramacrophage Mycobacterium avium complex (MAC). Clarithromycin potentiated the activities of rifampicin and rifalazil against both extracellular and intramacrophage MAC. In contrast, all the test quinolones exhibited antagonistic effects against extracellular MAC when combined with either clarithromycin or rifamycins. Such an antagonism was not observed for the activity of these combinations against intramacrophage MAC. Combined effects were observed with combinations of these fluoroquinolones with either ethambutol or streptomycin. Similar profiles were seen for the activities of two-drug combinations of clarithromycin or fluoroquinolones with other drugs against intramacrophage MAC isolated from pulmonary and disseminated MAC infections.  相似文献   
28.
We describe a 68-year-old man who underwent hyperbaric oxygen (HBO) therapy to manage radiation necrosis of the brain, which developed after two treatments with stereotactic radiosurgery (SRS) to the same lesion. The necrosis was subsequently treated with steroids alone for 2 months; however, he progressed clinically and radiographically. Improvement again was noted with the reinstitution of HBO therapy. This case suggests that HBO therapy is an important therapeutic option in the treatment of brain radiation necrosis caused by SRS.  相似文献   
29.
We investigated the pathway of differentiation in a case of mucinous carcinoma of the skin (MCS) arising on the right temple of a 70-year-old man. Histopathologic findings of the tumor showed evidence of apocrine-type differentiation such as distinctive decapitation secretion. Additionally, by employing a panel of antibodies, the immunohistochemical staining pattern of tumor cells was shown to be compatible with that of apocrine glands. Although the differentiation of this neoplasm remains controversial, the findings in our case suggest apocrine differentiation.  相似文献   
30.
Although cathepsin D has been implicated in prostate cancer invasion and metastasis, the distribution of this enzyme in normal human prostate is unknown. We investigated immunohistochemically the distribution of cathepsin D granules in normal prostatic tissues with or without androgen ablation. We also examined the cancer tissues after androgen ablation and the hyperplastic tissues. Changes in the distribution pattern of the larger cathepsin D-positive granules (apoptotic bodies) were observed in the normal prostate as well as in the normal tissue of the anti-androgen-treated cancer specimens. While the apoptotic bodies were denser in the proximal duct of the normal adult prostate, they were more abundant in the normal peripheral acini of the anti-androgen-treated cases. There were few apoptotic bodies in the adenoma tissues, but many in the hormonally treated cancer tissues. These results showed that the distribution pattern and density of cathepsin D granules well reflected the status of the human prostatic cells in relation to age, hormonal environment and hyperplastic or neoplastic change.  相似文献   
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