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991.
In this prospective study, we have compared women undergoing laparoscopic cholecystectomy, laparoscopic gynaecological surgery and laparoscopic minor gynaecological procedures (diagnostic, tubal, ligation) (n = 10 in each group) to determine if lower abdominal laparoscopy results in less postoperative pulmonary dysfunction than upper abdominal laparoscopy. Pulmonary testing was performed before operation, and 3 and 6 h after operation, on the first and second days after surgery. After operation, a significant reduction in forced vital capacity, forced expiratory volume in 1 s and peak expiratory flow rate occurred after laparoscopic cholecystectomy at each time. There were no significant changes after minor gynaecologic laparoscopy, whereas laparoscopic gynaecological surgery resulted in minor pulmonary dysfunction on the day of surgery only. We conclude that postoperative pulmonary function was less impaired after gynaecological laparoscopy than after laparoscopic cholecystectomy. This study suggests that the site of surgery is an important determinant of lung dysfunction after laparoscopy.  相似文献   
992.
AIMS: To assess the immunoexpression of cyclin D1 and retinoblastoma in a cohort of oesophageal squamous cell carcinoma cases from South Africa to see whether there is a relation between these two proteins. In addition, protein expression was correlated with clinicopathological features. METHODS: Fifty biopsies and 30 oesophagectomy specimens were immunostained with commercially available antibodies to cyclin D1 and retinoblastoma proteins, following microwave antigen retrieval. RESULTS: Twenty three of the 80 cases (29%) showed cyclin D1 protein expression. However, only five cases had > 50% of the tumour cells displaying immunopositivity. Three of the four cases with lymph node spread were cyclin D1 positive in the primary tumour and the metastasis. Fifty three cases were immunoreactive with the antiretinoblastoma antibody; 29 of these cases showing > 50% of cells with immunolabelling. Of the 23 cyclin D1 positive cases, 18 were also retinoblastoma positive. No correlation was observed between cyclin D1 and retinoblastoma protein expression and age, sex, race, or histological grade. CONCLUSIONS: Cyclin D1 is expressed in a minority of cases of oesophageal squamous carcinomas from South Africa. However, three of four cases with lymph node spread were cyclin D1 positive, thus indicating that cyclin D1 positive tumours may have a greater propensity for spread. In addition, 18 of 23 cyclin D1 positive cases also expressed retinoblastoma protein. These findings suggest a possible relation between cyclin D1 and retinoblastoma proteins in a proportion of cases of oesophageal squamous.  相似文献   
993.
Percentage depth dose data acquired during the revision of BJR Supplement 17: Central Axis Depth Dose Data for Use in Radiotherapy have been reviewed. Coverage of the half value layer (HVL) and field diameter rang was broad, although gaps were apparent at HVLs of 3-5 and 6-7 mm A1 and field diameters > 14 cm. Comparisons of submitted data with that in Supplement 17 indicate a generally even spread of data about the existing PDD values. Most data agreed to within +/- 5% at 2 cm and +/- 15% at 10 cm depth. Systematic discrepancies may be due to the use of different phantom materials. There is evidence that the spread of data is at least partially due to the problems of beam quality specification. The inadequacy of the first HVL as a specifier of beam quality is a well known and a more realistic specifier might be defined in terms of a broad beam dose ratio at defined depths, for a given beam geometry.  相似文献   
994.
995.
Twenty-two registered nurses employed in four long-term care facilities generated data for a study about nursing diagnoses in long-term care (N = 360). Generic outcome objectives were developed as an integral part of the project. The research team also specified exceptions to the outcomes: instances where meeting outcome objectives might not be possible. The outcome objectives and exceptions for the sample's 20 most frequently occurring nursing diagnoses are presented as working statements. The authors expect that these outcome objectives and exceptions will be revised by nurses who use them in practice, basic and continuing education, and research.  相似文献   
996.
Accuracy of diagnoses rendered using a live video telepathology network was assessed for permanent sections of surgical pathology specimens. To determine accuracy, telepathology diagnoses were compared with those obtained by directly viewing the glass slide using a standard microscope. A total of 294 cases were read via both telepathology and glass slide by attending pathologists at a tertiary care medical center. Overall accuracy was defined as exact concordance between diagnoses. Clinically insignificant differences in diagnoses were excluded to determine clinically significant accuracy. For the 285 cases with complete data, the overall accuracy for telepathology was 0.912 (95% confidence interval [CI], 0.872-0.941), whereas the overall accuracy for glass slide readings was 0.968 (95% CI, 0.939-0.985). This difference is statistically significant (p = 0.009). When focusing on clinically significant discrepancies, where the difference in diagnosis might affect therapeutic decisions, the video accuracy was only slightly less than the glass slide accuracy (0.965 [95% CI, 0.934-0.982] vs. 0.982 [95% CI, 0.957-0.994], respectively), but this difference is not statistically significant (p = 0.302). Most of the cases with clinically significant differences involved lesions with inherently high interobserver variation. Certainty of diagnosis did not differ between video and glass slide readings (p = 0.911), but there was an association between certainty of diagnosis and diagnostic accuracy for video (p = 0.003 for clinically significant accuracies). Based on these findings, we recommend when using this telepathology system that only preliminary diagnoses should be given in the following situations: for diagnostic areas with known high interobserver variability; when the consultant has any degree of uncertainty about the presence or absence of the lesion in question; and when there is insufficient experience using telepathology as a diagnostic medium.  相似文献   
997.
We report on a series of alkyl- and alkoxy-substituted 1,4-dihydroquinoxaline-2,3-diones (QXs), prepared as a continuation of our structure-activity relationship (SAR) study of QXs as antagonists for the glycine site of the N-methyl-D-aspartate (NMDA) receptor. The in vitro potency of these antagonists was determined by displacement of the glycine site radioligand [3H]-5,7-dichlorokynurenic acid ([3H]DCKA) in rat brain cortical membranes. In general, methyl is a good replacement for chloro or bromo in the 6-position, and alkoxy-substituted QXs have lower potencies than alkyl- or halogen-substituted QXs. Ethyl-substituted QXs are generally less potent than methyl-substituted QXs, especially in the 6-position of 5,6,7-trisubstituted QXs. Fusion of a ring system at the 6,7-positions results in QXs with low potency. Several methyl-substituted QXs are potent glycine site antagonists that have surprisingly high in vivo activity in the maximal electroshock (MES) test in mice. Among these, 7-chloro-6-methyl-5-nitro QX (14g) (IC50 = 5 nM) and 7-bromo-6-methyl-5-nitro QX (14f) (IC50 = 9 nM) are comparable in potency to 6,7-dichloro-5-nitro QX (2) (ACEA 1021) as glycine site antagonists. QX 14g has an ED50 value of 1.2 mg/kg iv in the mouse MES assay. Interestingly, alkyl QXs with log P values of 0.5 or less tend to be more bioavailable than QXs with higher log P values. QX 14g has 440-fold selectivity for NMDA vs alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, as determined electrophysiologically under steady-state conditions in oocytes expressing rat cerebral cortex poly(A)+ RNA. Overall, 14g was found to have the best combination of in vitro and in vivo potency of all the compounds tested in this and previous studies on the QX series.  相似文献   
998.
We investigated the influence of nutrition and exercise interventions within cognitive/behavioral and public health formats on weight and blood lipid profiles in obese children. Compliance was also examined as well as the relationship of the compliance measures with clinical outcome variables. Three conditions were compared over 16 sessions: nutrition and eating-habit change followed by exercise (NE), exercise followed by nutrition and eating-habit change (EN), and an information control (INFO). NE and EN were presented in a cognitive/ behavioral framework which focused on the development of self-regulation whereas the INFO condition received the same material in a public health/educational model. NE and EN participants evidenced modest, yet significant, reductions in weight and blood lipids, and the impact of these two interventions endured at a five-year follow-up. In contrast, INFO participants displayed stable weight and blood lipids during the course of the program, and most remained morbidly obese at follow-up. Improved nutrition, increased physical activity and fitness were significantly correlated with weight and lipid reductions.  相似文献   
999.
The stability of the hexameric glutamate dehydrogenase from the hyperthermophilic archaeon Pyrococcus furiosus at low pH values has been studied by activity assay, spectroscopic methods, size-exclusion chromatography and ultracentrifugation analysis. The enzyme is exceptionally stable and at pH 2.0 its hexameric assembly is preserved despite the changes observed in its tertiary structure. Below pH 1.7 dissociation into monomers starts and is accompanied by a progressive loss of tertiary interactions. Dissociation intermediate(s) were not detectable. At pH 2.0 the addition of NaCl causes the same structural changes observed upon further addition of protons. The monomeric state of the enzyme at pH 1.0 shows a significant content of native secondary structure and can be unfolded by guanidinium chloride. The role of electrostatic interactions in the high stability of the enzyme structure at low pH values is discussed.  相似文献   
1000.
The current environment in which medicine is taught and practiced requires that medical schools pay increased attention to the faculty member's roles, rewards, career development, and productivity. Medical schools must make strategic decisions about the allocation of resources that can nurture their faculties and support the activities in academic and community settings in which faculty are involved. From 1993 to 1995 Allegheny University of the Health Sciences (formerly Medical College of Pennsylvania and Hahnemann University) designed a comprehensive system for the professional development of faculty. This system is based upon expanded categories of faculty academic activity and scholarship. New programs were implemented to reorient faculty toward conducting and documenting the expanded array of scholarly activities. The main characteristics of the new system are the establishment of formally defined performance expectations, the vertical alignment of the individual faculty member's objectives with the department's mission and the school's mission, and an increasing emphasis upon faculty interdependence, accountability, and use of sound business practices. The authors describe these and other aspects of the design of the new system in detail and report initial results and lessons learned from the system's implementation, evaluation, and dissemination throughout the university. The long-term success of this comprehensive professional development program will be assessed over time by observing how this institution advances its mission in a well-planned and cost-effective manner that retains talented, productive, and professionally fulfilled faculty.  相似文献   
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