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排序方式: 共有610条查询结果,搜索用时 15 毫秒
1.
Dr. H. Ptok R. Steinert F. Meyer K.-P. Kröll C. Scheele F. Köckerling I. Gastinger H. Lippert 《Der Chirurg》2006,77(8):709-717
BACKGROUND: The laparoscopic resection of rectal cancer shows morbidity and oncological safety comparable to the open approach, but morbidity increases after conversion to open resection. No oncological long-term results are available for the latter patients. METHODS: From 01/01/2000-31/12/2002, patients with curatively resected rectal cancer enrolled in a observational study were evaluated for morbidity, mortality, tumor- and local recurrence rate, paying attention to patients with conversion from laparoscopic to open resection. RESULTS: 237 (3.3%) of 7,189 patients underwent laparoscopic resection (ITT). These patients showed significantly more T1/2 tumors (P<0.001) in earlier UICC stages (P<0.001) than open resected patients. 35 (14.8%) of 237 laparoscopic procedures were converted. Compared with patients receiving complete laparoscopic or open resection, these patients showed significantly higher frequencies of intraoperative (P<0.001) and general postoperative complications (P=0.003) as well as the highest overall morbidity (P=0.031). After a median follow-up of 30.1 months, the highest 5-year local recurrence rate was found in the converted group (16.0%). The laparoscopically resected patients showed a local recurrence rate of 3.3%, patients with open resection of 12.4% (P=0.082). The disease-free survival rate did not differ between the groups (P=0.585). CONCLUSION: Laparoscopic resection of rectal cancer provides oncological results similar to open resection. After conversion, the short and oncological long-term outcomes were worse. Considering a conversion rate of 15%, only a strict indication for the laparoscopic approach can be allowed, and laparoscopic resection should be performed at centers. 相似文献
2.
Using a simple mathematical model, we calculated the risk for a patient undergoing penetrating keratoplasty to receive a cornea from a human immunodeficiency virus-infected donor despite negative results on serologic testing of donor serum. This error in serologic testing occurred when false-negative results were obtained from the enzyme-linked immunosorbent assay used to screen donor corneas for human immunodeficiency virus exposure. The average risk of transplanting an infected cornea was low, 0.03%, but increased by a factor of ten when donor tissue from donors at high risk for AIDS was used. Current screening procedures are probably adequate to prevent transmission of human immunodeficiency virus, but increased vigilance for high-risk donor populations may be appropriate. 相似文献
3.
CD97, but not its closely related EGF-TM7 family member EMR2, is expressed on gastric,pancreatic, and esophageal carcinomas 总被引:2,自引:0,他引:2
Aust G Steinert M Schütz A Boltze C Wahlbuhl M Hamann J Wobus M 《American journal of clinical pathology》2002,118(5):699-707
CD97 expression is related closely to the dedifferentiation and tumor stage in thyroid carcinomas. We systematically examined the role of CD97 and its closest relative, EMR2, in normal and malignant gastric, esophageal, and pancreatic tissue. The normal tissues were EMR2-, whereas CD97 was expressed slightly in the parietal cells of gastric mucosa and in exocrine pancreatic cells. Interestingly, intralobular and interlobular pancreatic ducts were CD97+. All tumors were EMR2-. CD97 was expressed by 44 of 50 gastric, 14 of 18 pancreatic, and 10 of 13 esophageal carcinomas. Of the 44 gastric cancers, 27 showed disseminated or scattered tumor cells at the invasion front with stronger CD97 expression than tumor cells located in solid tumor formations. There was no correlation between CD97 levels in the tumors or soluble CD97 in the serum samples and the clinicopathologic features of the patients. Taken together, significant numbers of gastric, esophageal, and pancreatic carcinomas are CD97+, whereas its homolog, EMR2, does not have any role in such tumors. 相似文献
4.
Manfred Rtzsch Stefan Zschoche Volker Steinert Klaus Schlothauer 《Macromolecular chemistry and physics.》1986,187(7):1669-1679
Structural investigations on maleic anhydride (MAn) copolymers with ethene, propene and styrene, their products of hydrolysis, and their methyl half-esters by means of 13C NMR spectroscopy are presented. The spectra of 2,3-diethylsuccinic acid and its anhydrides in the erythro- and threo-configuration and of butylsuccinic acid and its anhydride were obtained and compared with the spectra of the copolymers. In each case the results show the formation of both threo(trans)- and erythro(cis)-structures. At a polymerization temperature of 60°C the proportions were 88% threo to 12% erythro for ethene/MAn copolymers and 80% threo to 20% erythro for propene/MAn copolymers, a ratio which was confirmed also by the hydrolyzed forms. Copolymerization at 150°C leads, in the case of propene/MAn, to 67% threo and 33% erythro. The production of ethene/MA copolymer via the copolymerization of ethene and fumaric acid half-ester and its saponification to ethene/fumaric acid leads to a ratio of 38% threo to 62% erythro. These results are in accordance with the thermal stabilities of the configurations. In the case of styrene/MAn copolymer it is not possible to obtain a unique interpretation of the configurations from the spectra. For the conversion of propene/MAn and styrene/MAn copolymers by means of methanol to half-esters it can be derived from the 13C NMR spectra how many of the half-ester moieties are obtained in the neighbourhood of the methyl and phenyl groups, respectively, of the olefin. 相似文献
5.
Aust G Sittig D Steinert M Lamesch P Lohmann T 《Clinical and experimental immunology》2002,127(3):479-485
The mechanisms by which T cells accumulate in the thyroid and support the autoimmune process in patients with Graves' disease (GD) are poorly understood. Chemokines and their receptors may be involved in this process. We have analysed the expression of CXCR3 and CCR5 as Th1-specific chemokine receptors, CCR3 as a marker for Th2 cells, CXCR4 (expressed on unprimed, naive T cells) and CCR2 (known to be involved in autoimmunity) on peripheral blood (PBL) and thyroid-derived lymphocytes (TL) using flow cytometry. Chemokine receptor expression on PBL of GD patients (n = 16) did not differ from that of normal controls (n = 10). In GD, CXCR3+ (67.3 +/- 4.0% versus 45.7 +/- 2.1%) and CCR5+ T cells (42.5 +/- 3.4% versus 18.8 +/- 2.1%) showed a significant enrichment in the TL compared to PBL. The positive cells were contributed mainly by the CD4+CD45R0+ subset. TL are mostly primed CD45R0+ T cells, but surprisingly, they had significantly higher levels of CXCR4+ cells among TL (96.2 +/- 1.0%) compared to PBL (66.8 +/- 4.2%). However, CXCR4 has been induced during in vitro isolation of TL. There was no correlation between chemokine receptors and the level of TSH-receptor and thyroid peroxidase autoantibodies. CCR3+ and CCR2+ cells remained unchanged in TL compared to PBL. We could confirm the results using RT PCR and immunohistology. In summary, TL showed a different chemokine receptor pattern compared to PBL from the same patient. This indicates a role for CXCR3 and CCR5 in the recruitment of T cells to the thyroid in GD. 相似文献
6.
7.
There is a large body of literature about increased figures for violence in schizophrenic in-patients and out-patients. The therapeutic efficacy of neuroleptics in coping with violent behaviour in schizophrenics is well documented. However, little data is available about the treatment given to schizophrenics who behave violently. We performed an extensive chart review in an unselected sample of n = 138 patients with schizophrenic or schizoaffective disorder (ICD10) and first admission between 1990 and 1993, including in-patient episodes in the first two years after first admission. Staff records were reviewed for all notes on aggressive behaviour (threats, physical aggression against persons and objects, selfdirected aggression) and coercive measures. For each incident, the number of days after the beginning of neuroleptic treatment was coded. 258 inpatient treatment periods with an average length of 78.5 days were evaluated; 226 lasted more than one week. 142 aggressive incidents were observed, of these 66% within the first week of neuroleptic treatment, 9% within the second. The day-by-day decline of aggressive incidents after the start of neuroleptic treatment was highly significant (trend-test: Spearman rank correlation r=0.964; df=5; t<-8.1; p<0.001). The results support the assumption that the increased figures for violence by schizophrenics are, at least in part, due to the lack of adequate treatment. 相似文献
8.
Background: Intellectual curiosity can be defined as a desire for knowledge that leads to exploratory behavior and consists of an inherent and stable trait (i.e. trait curiosity) and a variable context-dependent state (i.e. state curiosity). Although intellectual curiosity has been considered an important aspect of medical education and practice, its relationship to medical education has not been empirically investigated. The purpose of this exploratory study was to describe medical students’ intellectual curiosity across a four-year undergraduate program.Methods: We employed a cross-sectional design in which medical students, across a four-year undergraduate program at McGill University, completed the Melbourne Curiosity Inventory as a measure of their state and trait intellectual curiosity. A Mixed Models ANOVA was used to compare students across year of training.Results: Four hundred and two out of 751 students completed the inventory (53.5%). Trait curiosity was significantly higher than state curiosity (M?=?64.5, SD?=?8.5 versus M?=?58.5, SD?=?11.6) overall, and within each year of training.Conclusions: This study is the first to describe state and trait intellectual curiosity in undergraduate medical education. Findings suggest that medical students’ state curiosity may not be optimally supported and highlight avenues for further research. 相似文献
9.
Herbert Benson M.D. Roger F. Steinert B.A. Martha M. Greenwood B.A. Helen M. Klemchuk B.A. Norman H. Peterson 《Behavioral medicine (Washington, D.C.)》2013,39(1):37-44
Abstract A previous investigation has demonstrated that the practice of a meditational technique elicits a wakeful, hypometabolic state. Measurement of O2 consumption and CO2 elimination was made by sampling techniques; mean values of these parameters were calculated from 6–10 minute samples. The present study extends this investigation, using a recently developed method of continuous measurement of O2 consumption and CO2 elimination. Continuous measurement of these parameters permitted the determination of mean values for the entire experimental periods as well as for selected intervals and permitted the examination of the sequence of respiratory changes. The present study reports statistically significant decreases in O2 consumption of 5 percent and CO2 elimination of 6 percent for the entire 20 minutes of the meditation period. These are lower than the sample values of 16 percent and 15 percent reported in the previous study. However, when selected intervals of the meditation period are examined, decreases in O2 consumption and CO2 elimination are comparable to those previously reported. The results are consistent with the difference between the discontinuous sampling measurement method originally employed and the continuous measurement method of the present investigation. 相似文献
10.