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81.
Clinical and pathological characteristics of scirrhous carcinoma of the stomach were studied in 106 cases treated by gastrectomy between 1973 and 1983. The male to female ratio was 0.58. The percentage of scirrhous carcinomas to all gastric carcinomas resected in the same period was three times higher in females than males. The age distribution of the patients suggested that there were two peaks in the forties and sixties in the male, and in the thirties and fifties in the female. The incidence of scirrhous carcinoma in all types of gastric carcinoma was significantly higher in the twenties, thirties and forties compared to the lowest incidence in the seventies. In the female group the primary lesion had a tendency to be adjacent to the fundic gland area and to avoid intestinal metaplasia. In the male the opposite was recognized. Cancer nests with single cells or only several cells were common in this type of carcinoma. These findings suggest that there might be two biologically different scirrhous carcinomas both in the male and the female, the appearance of single carcinoma cells might be favored by female sex hormones and young ages, and not only the original gastric mucosa but also mucosa with intestinal metaplasia could be precursors of single carcinoma cells.  相似文献   
82.
We conducted a nationwide molecular epidemiological study of Clostridium difficile infection (CDI) in Japan investigated the correlation between the presence of binary toxin genes and CDI severity. This is the first report on molecular epidemiological analyses for CDI in multiple university hospitals in Japan, to our knowledge. We examined 124,484 hospitalized patients in 25 national and public university hospitals in Japan between December 2013 and March 2014, investigating antimicrobial susceptibilities and toxin-related genes for C. difficile isolates from stools. Epidemiological genetic typing was performed by PCR-ribotyping and repetitive sequence-based (rep)-PCR to examine the genetic similarities. The results detected toxin A-positive, toxin B-positive, binary toxin-negative (A+B+CDT?) detected from 135 isolates (80.8%) and toxin A-negative, toxin B-positive, binary toxin-negative (A??B+CDT?) in 23 (13.8%). Toxin A-positive, toxin B-positive, and binary toxin-positive (A+B+CDT+) were seen in 9 isolates (5.4%). Vancomycin (n = 81, 37.7%) or metronidazole (n = 88, 40.9%) therapies were undertaken in analyzed cases. Ribotypes detected from isolates were 017/subgroup 1, 070, 078, 126, 176, 449, 475/subgroup 1, 499, 451, 566 and newtypes. Rep-PCR classified 167 isolates into 28 cluster groups including 2–15 isolates. In addition, 2 pairs of strains isolated from different institutions belonged to the same clusters. Seven out of 9 (77.8%) of the patients with binary toxin producing strains had “mild to moderate” outcome in evaluated symptoms. In conclusion, we found that binary toxin did not show regional specificity and had no relevance to severity of CDI.  相似文献   
83.
The principle of empirical therapy for patients with intra-abdominal infections (IAI) should include antibiotics with activity against Enterobacteriaceae and Bacteroides fragilis group species. Coverage of Pseudomonas aeruginosa, Enterobacter cloacae, and Enterococcus faecalis is also recommended for hospital-associated IAI. A nationwide survey was conducted to investigate the antimicrobial susceptibility of pathogens isolated from postoperative IAI. All 504 isolates were collected at 26 institutions and referred to a central laboratory for susceptibility testing. Lower susceptibility rates to ciprofloxacin and cefepime were demonstrated in Escherichia coli. Among E. coli, 24.1% of strains produced extended-spectrum β-lactamase (ESBL). Carbapenems, piperacillin/tazobactam, cephamycins/oxacephem, aminoglycosides, and tigecycline had high activity against E. coli, including ESBL-producing isolates. Among E. cloacae, low susceptibility rates to ceftazidime were demonstrated, whereas cefepime retained its activity. P. aeruginosa revealed high susceptibility rates to all antimicrobials tested except for imipenem. Among B. fragilis group species, low levels of susceptibility were observed for cefoxitin, moxifloxacin, and clindamycin, and high susceptibility rates were observed for piperacillin/tazobactam, meropenem, and metronidazole. Ampicillin, piperacillin, and glycopeptides had good activity against E. faecalis. Imipenem had the highest activity against E. faecalis among carbapenems. In conclusion, we suggested the empirical use of antimicrobials with the specific intent of covering the main organisms isolated from postoperative IAI. Piperacillin/tazobactam, meropenem, or doripenem, are appropriate in critically ill patients. Combination therapy of cefepime (aztreonam in patients with β-lactam allergy) plus metronidazole plus glycopeptides, imipenem/cilastatin or cephamycins/oxacephem plus ciprofloxacin plus metronidazole are potential therapeutic options.  相似文献   
84.
85.
The discovery of the gene for cystic fibrosis (CF), the cystic fibrosis transmembrane conductance regulator (CFTR), brought about a new era in the study of this disease. Identification of the molecular target has yielded a flood of data that add to our understanding of the pathogenesis, diagnosis and treatment of CF. The CFTR protein is a cAMP-regulated Cl(-) channel with multiple functions in epithelial cells. In the exocrine pancreas the CFTR plays a key role in the apical Cl(-), HCO(3)(-), and water transport in duct cells. The severe loss of functions, caused by mutations of the CFTR gene, leads to pathological lesions of the pancreas. Over 1200 CFTR mutations and polymorphisms have been identified and their diversity may explain the high level of heterogeneity in the CF phenotype. Mutation analyses of the CFTR gene have revealed a spectrum of CFTR-related diseases that do not fit the classical CF picture but are associated with dysfunction of CFTR, such as chronic pancreatitis.  相似文献   
86.
Proliferative response of peripheral blood mononuclear cells (PBMC) to glutamic acid decarboxylase (GAD), which has been reported in patients with type 1 diabetes, was measured in type 2 diabetes, especially in patients with antibodies to GAD initially diagnosed as having type 2 diabetes (anti-GAD+ type 2 diabetes). We studied 12 patients with type 1 diabetes, 22 with anti-GAD+ type 2 diabetes, 31 with type 2 diabetes who were negative for anti-GAD (anti-GAD+ type 2 diabetes), and 30 healthy control subjects for cellular responses in vitro to GAD. The mean stimulation index (SI) in response to GAD was significantly higher in type 1 diabetes than in anti-GAD+ type 2 diabetes or healthy controls (1.47+/-0.35 vs. 1.11+/-0.35, P<0.05, and 1.06+/-0.07, P<0.05, respectively). The mean  相似文献   
87.
The identity of the cellular mechanisms through which nitroglycerin (glyceryl trinitrate, GTN) elicits nitric oxide (NO)-based signaling to dilate blood vessels remains one of the longest standing foci of investigation and sources of controversy in cardiovascular biology. Recent evidence suggests an unexpected role for mitochondria. We show here that bioconversion by mitochondria of clinically relevant concentrations of GTN results in activation of guanylate cyclase, production of cGMP, vasodilation in vitro, and lowered blood pressure in vivo, which are eliminated by genetic deletion of the mitochondrial aldehyde dehydrogenase (mtALDH). In contrast, generation of vasoactivity from alternative nitro(so)-vasodilators is unaffected. In mtALDH(-/-) mice and their isolated vascular tissue, GTN bioactivity can still be generated, but only at substantially higher concentrations of GTN and by a mechanism that does not exhibit tolerance. Thus, mtALDH is necessary and sufficient for vasoactivity derived from therapeutic levels of GTN, and, more generally, mitochondria can serve as a source of NO-based cellular signals that may originate independently of NO synthase activity.  相似文献   
88.
Objective : A hallmark of the systemic response to an inflammatory stimulus is the release of polymorphonuclear leukocytes (PMNs) from the bone marrow. This study was designed to measure the release of PMNs from the bone marrow and to determine their sequestration in the lung after an intravenous injection of either endotoxin (n = 5) or saline (n = 5). Methods and Results : The thymidine analogue 5′-bromo-2-deoxyuridine (BrdU) was used to pulse label dividing PMNs in the bone marrow of rabbits (n = 13), and immunohistochemistry and morphometry were used to detect the release of BrdU-labeled PMNs into the circulation and to determine their sequestration in the lung. Endotoxin treatment caused a drop in the circulating PMN counts (3.3 ± 0.08 at baseline to 0.12 ± 0.02 × 109/L at 1 hour after endotoxin), which was followed by a neutrophilia at 8 hours (6.3 ± 1.1 × 109/L, p < 0.01), an increase in circulating band cells (0.12 ± 0.01 at baseline to 2.18 ± 0.4 × 19/L at 8 hours, p < 0.001), and an increase in the percentage of BrdU-labeled PMNs (0.01% ± 0.004% at baseline to 26.1% ± 3.2% at 8 hours, p < 0.001). Endotoxemia caused an arteriovenous difference in BrdU-labeled PMNs across the lung (35.9% ± 2.9% versus 26.1% ± 3.1%, mixed venous versus arterial, p < 0.02). Morphometric studies showed that endotoxin caused sequestration of PMNs in the lung (2.2 ± 0.4 versus 1.0 ± 0.2 × 1010, endotoxin versus saline, p < 0.03) with preferential retention of BrdU-labeled PMNs (0.79 ± 0.21 versus 0.039 ± 0.016 × 1010, endotoxin versus saline, p < 0.05). The percentage of BrdU-labeled PMNs in the alveolocapillary walls was higher than in circulating blood (64.01% ± 4.3% versus 26.1% ± 3.2%, p < 0.01) in the endotoxin group. In vitro filtration of cells through 5-mm pore size filters showed that circulating BrdU-labeled PMNs, 8 hours after endotoxin, were preferentially retained in the filters (p < 0.01). Conclusions : We conclude that endotoxemia stimulates the bone marrow to release mature and immature PMNs. Compared to PMNs released from the bone marrow during normal turnover, these PMNs are less deformable and preferentially sequester in the lung microvessels.  相似文献   
89.
We used the Japanese Ministry of Health and Welfare criteria for acute pancreatitis to obtain a “prognosis score” for disease severity in 63 individuals with severe pancreatitis and we assessed the usefulness of these scores. To convert the Japanese criteria into a score, we excluded the CT grade classification, assigned a value of 1 point to the prognostic factors designated , and a value of 0.5 points to the prognostic factors designated , and added the number of points to obtain the “prognosis score”. The results showed a clear difference in prognosis between patients who had scores of 1.5 or less and those whose scores were 2.0 or more. These prognosis scores were useful both in rating the efficacy of treatment and in selecting the method of treatment in the early stage. To confirm the value of these scores, it will be necessary to accumulate more cases prospectively and to conduct additional assessments.  相似文献   
90.
OBJECTIVE: Insulin resistance has been implicated as an important initiating factor in coronary atherosclerosis. However, associations between insulin resistance and specific morphologic features of atherosclerotic coronary arteries remain unclear. We ultrasonographically evaluated the morphologic features of atherosclerotic coronary arteries in nondiabetic patients with insulin resistance. METHODS: Before intervention, 90 patients with 105 culprit lesions underwent intravascular ultrasound examination through which vessel area, lumen area and plaque area were evaluated. Expansive remodeling (lesion vessel area more than 5% greater than at the proximal reference segment) and constrictive remodeling (lesion vessel area more than 5% less than at the distal reference segment) were also evaluated. Insulin resistance was determined by homeostasis model assessment and defined as values above the 75th percentile (that is, 1.71). RESULTS: Insulin-resistant patients numbered 23, while nonresistant patients numbered 67. Culprit lesions in the insulin-resistant group showed larger vessel area (18.16 +/- 6.94 compared with 13.64 +/- 4.28 mm, P = 0.0001) and plaque area (16.64 +/- 6.78 compared with 12.05 +/- 4.12 mm, P = 0.0001) and more frequently showed expansive remodeling (56% compared with 14%, P < 0.0001) and calcific plaque (33% compared with 12%, P = 0.01). Multivariable logistic regression analysis identified only insulin resistance (odds ratio, 4.9, P = 0.008) as an independent predictor of expansive remodeling. CONCLUSIONS: Insulin resistance independently predicted expansive remodeling, underscoring the importance of insulin resistance in coronary atheroscrelosis.  相似文献   
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