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71.
72.
Wainwright AM Williams JR Carr AJ 《The Journal of bone and joint surgery. British volume》2000,82(5):636-642
We assessed the inter- and intraobserver variation in classification systems for fractures of the distal humerus. Three orthopaedic trauma consultants, three trauma registrars and three consultant musculoskeletal radiologists independently classified 33 sets of radiographs of such fractures on two occasions, each using three separate systems. For interobserver variation, the Riseborough and Radin system produced 'moderate' agreement (kappa = 0.513), but half of the fractures were not classifiable by this system. For the complete AO system, agreement was 'fair' (kappa = 0.343), but if only AO type and group or AO type alone was used, agreement improved to 'moderate' and 'substantial', respectively (kappa = 0.52 and 0.66). Agreement for the system of Jupiter and Mehne was 'fair' (kappa = 0.295). Similar levels of intraobserver variation were found. Systems of classification are useful in decision-making and evaluation of outcome only if there is agreement and consistency among observers. Our study casts doubt on these aspects of the systems currently available for fractures of the distal humerus. 相似文献
73.
多途径丝裂原激活的蛋白激酶介导一氧化氮引起的肝癌细胞凋亡 总被引:1,自引:0,他引:1
目的研究非离子型的diazeniumdiolate类一氧化氮供体引起肝癌细胞凋亡的分子机制.方法利用免疫印迹、免疫沉淀、凝胶阻滞实验研究一氧化氮供体处理Hep3B肝癌细胞后,丝裂原激活的蛋白激酶、AP-1的激活以及和Hep3B肝癌细胞凋亡的关系.结果一氧化氮可引起细胞外信号调节蛋白激酶、c-jun N末端激酶和p38激酶的激活,特别是细胞外信号调节的蛋白激酶的持续激活,其中细胞外信号调节的蛋白激酶和c-jun N末端激酶的特异的阻断剂U0126和JNK抑制剂Ⅱ可阻断AP-1的激活和Hep3B细胞的凋亡,而p38激酶的阻断剂SB203580不能阻断AP-1的激活和Hep3B肝癌细胞的凋亡.结论一氧化氮通过激活细胞外信号调节蛋白激酶、c-jun N末端激酶,进而激活AP-1而引起Hep3B肝癌细胞的凋亡. 相似文献
74.
Carr HA 《Journal of endourology / Endourological Society》2000,14(1):5-8
Although it is one of the most frequently utilized devices in the hospitalized patient, the Foley catheter has often been taken for granted. This lack of attention is unfortunate, as the Foley catheter remains one of the primary sources of hospital-acquired infections, which increase morbidity, mortality, and the financial burden on the healthcare system. Although education on the appropriate techniques, proper use, and early removal of Foley catheters is important, such measures unfortunately result in transient benefits. Current technologic advancements have moved the coating technology to a state where bacterial adhesion and migration can be limited and the frequency of catheter-associated urinary tract infections can be reduced. Future technological advances in the Foley catheter will help provide better care and comfort for the catheterized patient. 相似文献
75.
PURPOSE: Irradiation of the small intestine in the mouse induces damaging structural alterations to the architecture of the enteric mucosa. There is growing interest in the possible relevance of underlying additional pathology when appreciating the total response of tissues to irradiation. The possibility that small intestinal mucosal abnormalities in the streptozotocin-induced diabetic mouse may exacerbate radiation-induced injury was tested by examining the combined effects of the two treatments. MATERIALS AND METHODS: Streptozotocin-diabetic and -non-diabetic mice were exposed to 10 Gy abdominal X-radiation. Profiles of mucosal epithelial cell populations were quantified and comparisons with corresponding groups of unirradiated mice made on the third day post-irradiation. RESULTS: The histological appearances of the small intestinal mucosa were similar in both groups of irradiated mice, but the numbers of profiles of crypts and of columnar, goblet, Paneth and entero-endocrine cells were depressed in these groups when compared with values in corresponding groups of unirradiated mice. However, the expression of radiation damage in the diabetic mouse was less severe than in the non-diabetic mouse, particularly in the jejunum where the changes attendant on the onset of diabetes were most marked. CONCLUSION: These findings suggest that the response of mouse to radiation may be moderated by the presence of this type of pathophysiology. However, there is no evidence that the damage produced by streptozotocin-induced diabetes and radiation is additive. 相似文献
76.
Differential distribution of metabotropic glutamate receptors 1a, 1b, and 5 in the rat spinal cord 总被引:9,自引:0,他引:9
Alvarez FJ Villalba RM Carr PA Grandes P Somohano PM 《The Journal of comparative neurology》2000,422(3):464-487
Metabotropic glutamate receptors (mGluRs) modulate somatosensory, autonomic, and motor functions at spinal levels. mGluR postsynaptic actions over spinal neurons display the pharmacologic characteristics of type I mGluRs; however, the spinal distribution of type I mGluR isoforms remains poorly defined. In this study, the authors describe a differential distribution of immunoreactivity to various type I mGluR isoforms (mGluR1a, mGluR5a,b, and mGluR1b) that suggests a correlation between specific isoforms and particular aspects of spinal cord function. Two different antisera raised against mGluR5a,b detected intense immunoreactivity within nociceptive afferent terminal fields (laminae I and II) and also in autonomic regions (parasympathetic and sympathetic). In contrast, two of three anti-mGluR1a antibodies did not immunostain lamina I or II. Laminae I and II immunostaining by a third anti-mGluR1a antibody was competed by a peptide sequence obtained from a homologous region in mGluR5, suggesting possible cross reactivity in fixed tissue. Autonomic neurons did not express mGluR1a immunoreactivity. All anti-mGluR1a antibodies strongly and specifically immunolabeled dendritic and somatic membranes of neurons in the deep dorsal horn (lamina III-V) and the ventral horn (lamina VI-IX). Somatic motoneurons expressed mGluR1a immunoreactivity but little or no mGluR5 immunoreactivity. Phrenic and pudendal motoneurons expressed the highest level of mGluR1a immunoreactivity in the spinal cord. Intense mGluR1b immunoreactivity was restricted to a few scattered neurons and a prominent group of neurons in lamina X. Lamina II neurons expressed low levels of mGluR1b immunoreactivity. Ultrastructurally, type I mGluR immunoreactivity was found mostly at extrasynaptic sites on the plasma membrane, but it was also found perisynaptically, in the body of the postsynaptic regions or in relation to intracytoplasmic structures. 相似文献
77.
The presence of reserve nitrous oxide cylinders on anaesthetic machines is not necessary and potentially hazardous, wasteful and polluting. Although reserve nitrous oxide cylinders are routinely present on the anaesthetic machines in many hospitals in the UK, it is our concern that they are not checked or maintained properly. We examined a sample of cylinders and surveyed the practice amongst the anaesthetic staff in our Department with an anonymous questionnaire. This confirmed that: (1) the equipment is not properly maintained, 68% of cylinders sampled having passed a 3-year expiry date; (2) checks are of little practical use, are not routinely performed by anaesthetists, and only 46% of respondents routinely check the nitrous oxide cylinders. In conclusion, the nitrous oxide cylinders are not properly checked or maintained and may represent a safety hazard. 相似文献
78.
79.
Are obstetric risk factors and bowel symptoms associated with defaecographic and manometric abnormalities in women awaiting hysterectomy? 总被引:2,自引:0,他引:2
P J Arumugam B Patel G Rieck H Hutchings S Emery N D Carr J Beynon 《Journal of obstetrics and gynaecology》2004,24(3):274-278
Abdominal hysterectomy has been shown to affect anorectal function. These studies are either population-based or have been performed retrospectively. It is not clear from the literature whether those subjects awaiting hysterectomy already have an element of pelvic floor failure and which may be related to obstetric risk factors. A complete anorectal assessment was performed in a group of women awaiting hysterectomy who did not volunteer any bowel symptoms. The patients studied were part of an ongoing study of the functional effects of abdominal hysterectomy. All had their anorectal function assessed before their respective surgery by a questionnaire (functional bowel score), Cleveland continence score, endoanal ultrasound (U/S), anal manometry, defaecatory proctogram and colonic transit. A detailed obstetric history, which included risk factors such as parity, type of delivery, duration of labour and elevated birth weight, were also recorded. Patients with previous bowel disease, bowel surgery and anal sphincter repair were excluded. There were 39 subjects with a median age of 43 years (range 31-65), respectively. Thirty-three rectocoeles and 22 intussusceptions were demonstrated. Two had poor puborectalis function, while five had cough incontinence. Two women had abnormal colonic transit. Thirteen had abnormal anal manometry. Endoanal ultrasound was normal in all patients. None of the obstetric risk factors were associated with rectocoele, intussusception or abnormal anal manometry. Low squeeze pressure was associated significantly with more bowel symptoms (P=0.03). However, rectocoele, intussusception, abnormal colonic transit, abnormal resting anal pressure and maximal tolerated volume were not statistically significantly associated with bowel symptoms. The majority of female subjects who were awaiting hysterectomy had physiological and proctographic abnormalities consistent with pelvic floor failure. Obstetric risk factors were not associated with rectocoele, intussusception, abnormal colonic transit and anal manometry in this cohort of patients. Similarly, the majority of proctographic abnormalities were not associated with bowel symptoms. However, a trend was noted associating bowel symptoms with manometric abnormalities. 相似文献
80.
Carr JA Havstad S Zarbo RJ Divine G Mackowiak P Velanovich V 《Archives of surgery (Chicago, Ill. : 1960)》2000,135(12):1469-1474
HYPOTHESIS: Amplification of the HER-2/neu oncogene in 25% of breast cancers is associated with a shortened disease-free survival. DESIGN: Retrospective analysis of a patient population referred to a tertiary care facility for HER-2/neu testing. The mean follow-up was 56 months. SETTING: Large, urban, tertiary care hospital. PATIENTS: From 1995 to 1999, a consecutive sample of 190 patients with breast cancer had tissue samples tested for overexpression of the cell surface oncoprotein by immunostaining (IM) or amplification of the HER-2/neu oncogene by fluorescence in situ hybridization or both. Forty-nine subjects were excluded because they had tissue samples tested at our institution but received their treatment elsewhere. All patients tested for HER-2/neu after diagnosis with breast cancer in 1999 (n = 47) were excluded from analysis because of short follow-up time. One patient was excluded who had in situ ductal carcinoma. The remaining 93 patients were analyzed. RESULTS: Of 93 patients, 40 (43%) had gene amplification. Overall, patients with oncogene amplification had a shorter median disease-free interval (22 months) compared with controls (40 months) (P =.003). Analysis by the Cox regression model showed that the HER-2/neu status remained significantly associated with time to relapse even after adjusting for age and tumor grade (P =.002; adjusted relative risk, 2.4; 95% confidence interval, 1.4-4.4). No association was found between gene amplification and tumor grade (P =.98), estrogen/progesterone receptor status (P = .29 and P = .43, respectively), or lymph node status (P = .98). Seventy-two patients (77%) eventually had disease recurrence, with 18 (25%) of these recurring locally. CONCLUSIONS: The HER-2/neu oncogene is an independent prognostic indicator of a subset of breast cancers that are at high risk of early recurrence, regardless of tumor grade, estrogen/progesterone receptor status, and lymph node status. Patients amplifying the HER-2/neu oncogene have a shorter disease-free survival than patients without the oncogene. 相似文献