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1.
The aim of this study was to determine whether preoperative physiologic factors can account for and be used to predict the development of postoperative dysphagia after laparoscopic Nissen fundoplication. One hundred sixty-three patients with gastroesophageal reflux disease underwent laparoscopic Nissen fundoplication with a median follow-up of 14 months (range 6 to 81 months). Preoperative dysphagia was present in 37% (60 of 163) and was relieved in all but five patients (92%). Female sex (P = 0.01) and the presence of a stricture (P = 0.02) were the only preoperative variables associated with the presence of preoperative dysphagia. Eight percent (8 of 103) of patients without preoperative dysphagia developed new-onset dysphagia, and of these 63% (5 of 8) had a normal lower esophageal sphincter (LES) (pressure >6 mm Hg; length >2 cm; abdominal length >1 cm). New-onset dysphagia was significantly more common in patients with a normal LES (22% [5 of 23] vs. 4% [3 of 80], P = 001). Patients with a normal LES had almost a sixfold increase in the risk of developing dysphagia as those with an abnormal LES (relative risk = 5.8). Only a preoperative normal LES (P = 0.02) or mean LES pressures (P = 0.04) were positively associated with the development of postoperative dysphagia. The severity of this dysphagia also showed a strong positive trend of increasing with mean preoperative LES pressures (P = 0.07). Finally, preoperative LES pressure significantly correlated with postoperative LES pressure (r = 0.48, P = 0.01) and with mean residual LES (nadir) pressure (r = 0.33, P = 0.05) offering insight into the mechanism of this dysphagia. In conclusion, preoperative LES parameters play a role in the development of dysphagia after laparoscopic Nissen fundoplication. Patients with a normal LES or high mean LES pressures are at increased risk for developing this complication and should be informed of this before laparoscopic Nissen fundoplication. Presented at the Forty-Second Annual Meeting of The Society for Surgery of the Alimentary Tract, Atlanta, Ga., May 20–23, 2001.  相似文献   
2.
Protracted or recurrent pain and inflammation in the early neonatal period may cause long-lasting changes in central neural function. However, more research is necessary to better characterize the long-term behavioral sequelae of such exposure in the neonatal period. Objectives: (1) to study whether timing of postnatal exposure to persistent inflammation alters responsiveness to thermal pain in the adult animal; (2) to assess whether animals experiencing early postnatal chronic inflammation display altered anxiety related behavior; (3) to study the importance of genetic background. Newborn mice (outbred strain, CD1 and F1 hybrid strain, B6C3F1) received an injection of Complete Freund's Adjuvant (CFA) or saline on either postnatal day 1 or 14 (PND1; PND14) into the left hind paw. Pain to radiant heat and anxiety were examined in 12-week-old adult animals. Adult baseline PWL was significantly decreased in CD1 mice exposed to CFA on PND 1 and 14 as compared to their saline treated counterparts. B6C3F1 mice exposed to CFA on PND14 showed markedly reduced baseline PWL compared to the PND14 saline group. Persistent inflammation experienced by B6C3F1 mice on PND1 failed to affect baseline adult thermal responsiveness. Adult mice, CD1 and B6C3F1, displayed low anxiety traits only if they had been exposed to persistent inflammation on PND1 and not on PND14. Our research suggests a role for genetic background in modulating long-term behavioral consequences of neonatal persistent inflammation: the data support the hypothesis that pain experienced very early in life differentially affects adult behavioral and emotional responsiveness in outbred (CD1) and hybrid mice (B6C3F1).  相似文献   
3.
硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
4.
Summary In a nationwide incident case-referent study stepwise univariate analysis has revealed several risk determinants for childhood diabetes mellitus. In a multivariate analysis we have determined the set of risk determinants that would independently predict childhood Type 1 (insulin-dependent) diabetes. Possible interactions between the risk determinants and differences in risk profiles with different ages at onset were also examined. Reported familial insulin-treated and non-insulin-treated diabetes were significant risk factors in all age groups, as was also a low frequency of milk intake. The frequency of infections and a high intake of foods rich in nitrosamine tended to interact (OR 11.8, p=0.053) indicating a synergistic effect. A Cox regression analysis revealed that stressful life events during the last year was the only variable that tended to affect the age at onset (p=0.055). This indicated that psychological stress may rather precipitate than induce Type 1 diabetes. A short breast-feeding duration (OR=3.81), and an increased body height (OR=3.82) contributed significantly to the predictive model in only the youngest age group (0–4 years). An increased frequency of infections in the year preceding onset (OR=2.15) and no vaccination against measles (OR=3.33) contributed significantly to the model only in the age group 5–9 years. Various nutrients had different impacts on the risk of developing Type 1 diabetes in different age groups. It is concluded that in the genetically susceptible child, risk factors which are associated with eating habits, frequency of infections, vaccination status, growth pattern and severe psychological stress affect the risk of developing diabetes independently of each other. The set of risk determinants varies with the age at onset. A high frequency of infections and a high frequency of nitrosamine-rich food intake seem to have a synergistic effect on the risk of developing diabetes in childhood.  相似文献   
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7.
Summary At present there are several grading systems for prostatic carcinoma. Most are difficult to reproduce. An objective method of grading seems to be necessary and could make comparisons between various groups of patients easier and grading more reliable.In the present study morphometrically estimated nuclear size and variation in nuclear size are matched with the survival rates of 207 patients who underwent total perineal prostatetomy for cancer. On the basis of morphometrically estimated variation in nuclear size the patients could be divided into two groups with significantly differing survival rates. In this way it was possible to split the group of patients with grade 2 carcinoma (Mostofi's grading system) into two groups of patients with significantly different survival rates. The survival rates in these two groups did not differ significantly from those in the patients with Grade 1 and Grade 3 tumors respectively.The results are discussed in the light of the recent literature on the subject. Morphometry seems to be a valuable tool in grading prostatic cancer.  相似文献   
8.
Recombination of deltaRec to psiJalpha will delete the TCR delta gene, which is thought to play an important role in the bifurcation of the TCR alphabeta versus TCR gammadelta differentiation lineages. We recently detected a DNA-binding protein in human thymocytes, the so- called PJA-BP, which recognizes the psiJalpha gene segment and might be one of the factors involved in the regulation of preferential deltaRec- psiJalpha rearrangements. We now investigate PJA-BP expression and its correlation with TCR delta gene deletion in thymocytes. Our electrophoretic mobility shift assay experiments showed that the PJA-BP is evolutionary conserved in human, murine and simian thymocytes. Using a large series of human hematopoietic malignancies (n = 30), we conclude that PJA-BP expression is thymocyte specific and seems to be restricted to thymocytes committed to the TCR alphabeta lineage. Analysis of seven well-defined human thymocyte subpopulations showed that preferential deltaRec-psiJalpha rearrangements as well as PJA-BP expression can be detected from the immature CD34-/CD1+/CD3- /CD4+/CD8alpha+beta- thymocyte differentiation stage onwards. These experiments indicate that expression of PJA-BP in human thymocytes starts simultaneously with preferential deltaRec-psiJalpha rearrangements, which supports our hypothesis that PJA-BP is one of the factors involved in the preferential recombination of deltaRec to psiJalpha.   相似文献   
9.
The study investigates the correlation between oocyte maturity and fertilization and a variety of hormonal parameters in follicular fluid and ovarian granulosa cells. A methodology for purification of granulosa cells from contaminating blood cells is also established. A total of 63 follicular aspirates were collected at oocyte retrieval from 30 women superovulated using the long luteinizing hormone- releasing hormone (LHRH analogue)/human menopausal gonadotrophin regimen. Oestradiol, progesterone, testosterone and human chorionic gonadotrophin (HCG) were quantified in follicular fluid and granulosa cells were immunostained for human chorionic gonadotrophin. Immunopurification of granulosa cells from contaminating blood cells was performed. HCG in follicular fluid was significantly high in follicles yielding immature (grade 3) oocytes (P=0.002); there was no correlation with fertilization. Aspirates from follicles containing mature (grade 1) oocytes and oocytes that subsequently fertilized had significantly more granulosa cells immunobound to HCG (P < 0.001, P=0.02). Moreover, the immunomagnetic purification technique provided >98% pure population of granulosa cells. The data demonstrate that HCG in follicular fluid and on granulosa cells may help to predict oocyte maturity and fertilization. Furthermore, immunomagnetic beads provide a reliable procedure for the purification of ovarian granulosa cells.   相似文献   
10.
The morphology of cells and the hemagglutinogens isolated from cultures of Bordetella pertussis, Bordetella bronchiseptica, and Bordetella parapertussis were studied by electron microscopy with the negative-staining technique. Cells of all three species had long, thin (3 nm thick), peritrichously arranged fimbriae on the cell surface. Similar structures were found in purified hemagglutinogen preparations together with shorter fimbrial structures 3 nm thick and from 40 to 100 nm long. In one experiment, long, thin fimbriae isolated from B. pertussis were found to be arranged in a crystalline structure on the specimen grid after negative staining. Optical diffraction analysis with a filtering technique performed on micrographs of these structures revealed 12.5-nm-long substructures within individual fimbriae. Further analysis resolved each of these structures into three globules, a central globule 3.5 nm in diameter and two diametrically opposed globules 2.5 nm in diameter. Based on this substructural composition, it is suggested that subunits of the individual fimbriae are connected by fragile regions. The presence of such regions would explain the size heterogeneity of the filamentous structures observed in preparations of hemagglutinogens isolated from cultures of B. pertussis and B. bronchiseptica. The concept that the short filamentous structures present in purified preparations of hemagglutinogens originate from the surface fimbriae present on the cells is supported.  相似文献   
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