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排序方式: 共有663条查询结果,搜索用时 15 毫秒
1.
A systematic examination was performed for environmental food contamination by Salmonella in poultry farms, broiler chickens, broiler processing plants and meat on the market. Salmonella was isolated from 219 of 1197 samples and the serotypes showed a wide distribution. (Table 1-1). S. hadar accounted for 37.1% (96) of all isolations (259). The contamination rate of broiler chickens on arrival at broiler processing plants is relatively low. However, in the broiler processing plants, containers, processing machinery, cooling water and slaughters were highly contaminated by Salmonella, S. hadar being the most prominent serotype in the plants. 64% of chicken meat on the market was contaminated by Salmonella, S. hadar being the second most prominent serotype. 11% of the pork and none of the beef or horseflesh was contaminated by Salmonella. These results indicate that poultry is the main source of S. hadar infection in humans. However, no S. hadar was isolated from cultures of 119 samples of feed for chickens from each delivery (Table 1-1). Thus, as the main source of infection by S. hadar of broiler chickens, an association with the feed seems to be ruled out. S. hadar was isolated at three of 18 poultry farms within Shizuoka Prefecture. Follow-up studies were performed at the three poultry farms which revealed that in two of them, Salmonella was completely eradicated on completion of disinfection. In the other one farm, which is still being disinfected, various strains of Salmonella including S. hadar still survived. We conclude that the main cause of the problem is the magnification of contamination of Salmonella-free material during the process at the broiler processing plants.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Eighty-three hips in 66 patients with nontraumatic avascular necrosis of the femoral head (ANFH) showing evidence of severe collapse or secondary osteoarthritic changes were treated with surgical implantation of bipolar hip prostheses either with or without cement fixation of femoral stems. The cases were observed for more than three years (range, three to ten years seven months; average, five years seven months) and assessed in terms of functional and roentgenographic results. These data were compared with the results of classic hemiarthroplasties using fixed head prostheses (Austin-Moore-type with curved or straight stem) that were performed at the authors' institutions before 1980. The results confirm that the clinical outcome is improved with use of the bipolar prosthesis. Satisfactory results (a score of 80 or greater on a hip function scoring system proposed by the Japanese Orthopaedic Association) were maintained throughout the follow-up period in most cases (71 of 83 hips) with the bipolar prosthetic replacements. In a group of patients with unsatisfactory results (12 hips), proximal migration of prosthetic head was seen in two cases. The incidence of proximal migration of bipolar heads, including those exhibiting minimal movement, was significantly lower when compared with that observed in an Austin-Moore-type head-fixed prosthesis group (7/83 versus 12/19) during a comparable postoperative follow-up period. It is noteworthy that the proximal migration of the bipolar head was not progressive, and, in most cases observed more than five years, the cartilaginous spaces of acetabulum were preserved, whereas in the Austin-Moore-replaced group, the migration was evident and progression occurred within three years of surgery.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
We assessed the results of Chiari pelvic osteotomy in 64 hips with early osteoarthritis in terms of acetabular labral detachment detected pre-operatively by arthrography. At an average follow-up of four years, assessment by the Merle d'Aubigńe score showed 83% excellent or good results. These satisfactory results were achieved in only half the cases with a detached labrum, but in nearly all cases with normal or torn acetabular labra. Other factors such as the acetabular index, the level and angle of osteotomy, and the displacement following osteotomy did not affect the results. Chiari pelvic osteotomy is a worthwhile procedure for early osteoarthritis in selected cases, but a detached acetabular labrum increases the risk of clinical failure.  相似文献   
4.
The left ventricular assist device (LVAD) is usually used in patients with end-stage heart failure as a bridge to transplantation. Recently, some studies have reported functional recovery with the use of an LVAD, although the mechanisms responsible for recovery are not fully understood. We investigated the functional recovery of the infarcted, failing rat heart in response to mechanical unloading after heterotopic transplantation. Heart failure was induced in Lewis rats by ligating the left anterior descending artery. After 4 weeks, the infarcted hearts were harvested and heterotopically transplanted. The transplanted infarcted heart was removed after 2 weeks of unloading and examined for hypertrophy and fibrosis, as well as for mRNA levels encoding for brain natriuretic peptide, sarco(endo)plasmic reticulum Ca(2+)-ATPase2a (SERCA2a), and beta1- and beta2-adrenergic receptors. Normal and infarcted rats without transplantation served as control animals. The infarcted heart was hypertrophied as evidenced by an increase in heart weight and myocyte diameter. After unloading the infarcted heart for 2 weeks, there was a decrease in heart weight and myocyte diameter. However, the percentage of myocardial fibrosis increased after unloading. The mRNA expression of brain natriuretic peptide and the beta2-adrenergic receptor significantly improved after mechanical unloading. The levels of SERCA2a mRNA tended to increase after unloading. In conclusion, unloading the failing, infarcted heart can help normalize left ventricular hypertrophy and cardiac gene expression. This unloading model appears to partially mimic the conditions of hemodynamic support with an LVAD in heart failure patients and potentially offers insights into the mechanisms of functional recovery.  相似文献   
5.
The urethral duct and vagina are formed from the urogenital sinus (UGS) during the early neonatal period in mice. Neonatal estrogen exposure results in hypospadias, or the malpositioning of vaginal and urethral openings, with wide cleft clitoris. We sought to characterize diethylstilbestrol (DES) influence on UGS morphogenesis and hypospadias formation. Newborn (day 0) and 1–4‐day‐old female mice (ICR/Jcl) were given (s.c.) oil or 3.0 μg DES. Animals were killed 24 hr later; then hypospadias formation and epithelial apoptosis and proliferation within the developing UGS were assessed. DES did not alter normal UGS morphogenesis by day 1, in comparison with controls. However, hypospadias formation was observed in DES‐treated mice by day 3. In these mice, the distal dorsal urethral duct appeared to fuse with and open into the lower vaginal solid cord region. Further, DES treatment produced a gradual significant increase in dorsal urethral epithelial apoptosis (P < 0.05) just prior to and during fusion and hypospadias formation. DES‐induced urethral epithelial and sinus cord proliferation appeared significantly increased (P < 0.05) and unchanged, respectively, just prior to fusion. By day 5, DES‐treated mice exhibited wide cleft clitoris. In addition, if DES was given on day 3 or 5, a gradual, distinct caudal shift in the vaginal‐urethral junction was observed compared to mice treated on days 0–2. Although hypospadias was not induced when neonates were given DES on day 7, these mice continued to display early vaginal opening. Dose‐response analysis indicated that 0.03 μg DES for 5 days is the lowest known critical dose for hypospadias induction. We have shown for the first time that DES‐induced hypospadias onset may primarily be the result of changes in developing dorsal urethral epithelial cell apoptotic and proliferative activity, and that the location of DES‐induced hypospadias formation is dependent on age at time of exposure. Anat Rec 266:43–50, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
6.
Corneal disease is the most common cause of bilateral blindness in the world. Visual loss in this condition is often due to changes in morphology and function of the corneal epithelial surface. Corneal disease-1 (corn1) and corn1(2J) are spontaneous mouse mutants that develop irregular thickening of the corneal epithelium, similar to that observed in human corneal surface disease. These autosomal-recessive mutations cause an increase in the rate of proliferation of the corneal epithelial cells. Here, we report that the phenotypes in both mutants are caused by mutations within the destrin gene (also known as actin-depolymerizing factor). By positional cloning, we identified a deletion encompassing the entire coding sequence of the destrin gene in corn1 mice, and a point mutation (Pro106Ser) in the coding sequence of destrin in corn1(2J) mice. In situ analysis showed that destrin is highly expressed in the corneal epithelium. Consistent with the cellular roles for destrin, an essential regulator of actin filament turnover that acts by severing and enhancing depolymerization of actin filament, we observed that the corn1 mutations increased the content of filamentous actin in corneal epithelial cells. Our results suggest an in vivo connection between remodeling of the actin cytoskeleton and the control of cell proliferation, and a new pathway through which an aberrant actin cytoskeleton can cause epithelial hyperproliferation.  相似文献   
7.
BACKGROUND: Intermittent delivery of warm cardioplegia provides a bloodless surgical field, but it is clinically important to evaluate the periods of normothermic ischemia. The aims of this study are to compare intermittent antegrade warm blood cardioplegia (IAWBC) with intermittent antegrade cold blood cardioplegia (IACBC) groups in terms of myocardial protection, and also to evaluate whether the length of ischemic time in the IAWBC group has an effect on myocardial dysfunction. METHODS: This study is based on a retrospective review of patients who underwent elective coronary artery bypass surgery: 162 consecutive patients with IAWBC and 107 consecutive patients with IACBC. RESULTS: The creatinine kinase peak was smaller in the IAWBC group compared with the IACBC group (p<0.0001). The cardiac index after cardiopulmonary bypass was higher in the IAWBC group (p<0.02), and the amount of inotropic support required to wean from cardiopulmonary bypass was less in the IAWBC group compared with the IACBC group (p<0.0001). CONCLUSIONS: IAWBC with 30 minutes of ischemia provides to be clinically acceptable myocardial protection for coronary bypass surgery.  相似文献   
8.
The KEYNOTE‐659 study evaluated the efficacy and safety of first‐line pembrolizumab plus S‐1 and oxaliplatin (SOX) (cohort 1) or S‐1 and cisplatin (SP) (cohort 2) for advanced gastric/gastroesophageal junction (G/GEJ) cancer in Japan. Herein, we update the results of cohort 1 and describe the results of cohort 2. This open‐label phase IIb study enrolled patients with advanced programmed death‐ligand 1 (PD‐L1)‐positive (combined positive score ≥ 1) human epidermal growth factor receptor 2 (HER2)‐negative G/GEJ adenocarcinoma. The primary end‐point was the objective response rate (ORR). Other end‐points were duration of response (DOR), disease control rate (DCR), progression‐free survival (PFS), overall survival (OS), and safety. One hundred patients were enrolled. In cohorts 1 and 2, median follow‐up time was 16.9 and 17.1 months; ORR (central review), 72.2% and 80.4%; DOR, 10.6 and 9.5 months; DCR (central review), 96.3% and 97.8%; median PFS (central review), 9.4 and 8.3 months; and median OS, 16.9 and 17.1 months, respectively. Treatment‐related adverse events (TRAEs) occurred in all patients, including peripheral sensory neuropathy (94.4%, cohort 1), decreased neutrophil count (82.6%, cohort 2), nausea (59.3% and 60.9% in cohorts 1 and 2), and decreased appetite (61.1% and 60.9% in cohorts 1 and 2). Grade 3 or higher TRAEs were reported by 59.3% (cohort 1) and 78.3% (cohort 2), including decreased platelet count (14.8%, cohort 1) and decreased neutrophil count (52.2%, cohort 2). Pembrolizumab in combination with SOX or SP showed favorable efficacy and safety in patients with PD‐L1‐positive, HER2‐negative G/GEJ adenocarcinoma.  相似文献   
9.
The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA). Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including 3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed.  相似文献   
10.
Whole-genome sequencing of non-H2S-producing Salmonella enterica serovar Typhimurium and S. enterica serovar Infantis isolates from poultry meat revealed a nonsense mutation in the phsA thiosulfate reductase gene and carriage of a CMY-2 β-lactamase. The lack of production of H2S might lead to the incorrect identification of S. enterica isolates carrying antimicrobial resistance genes.  相似文献   
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