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991.

Background

Carcinoma in situ (CIS) is a poor prognostic finding in urothelial carcinoma. However, its significance in muscle-invasive urothelial carcinoma (MIUC) treated with neoadjuvant chemotherapy (NAC) is uncertain. We assessed the effect of CIS found in pretreatment transurethral resection of bladder tumor (TURBT) biopsies on the pathologic and clinical outcomes.

Materials and methods

Subjects with MIUC treated with NAC before cystectomy were identified. The pathologic complete response (pCR) rates stratified by TURBT CIS status were compared. The secondary analyses included tumor response, progression-free survival (PFS), overall survival (OS), and an exploratory post hoc analysis of patients with pathologic CIS only (pTisN0) at cystectomy.

Results

A total of 137 patients with MIUC were identified. TURBT CIS was noted in 30.7% of the patients. The absence of TURBT CIS was associated with a significantly increased pCR rate (23.2% vs. 9.5%; odds ratio = 4.08; 95% CI: 1.19–13.98; P = 0.025). Stage pTisN0 disease was observed in 19.0% of the TURBT CIS patients. TURBT CIS status did not significantly affect the PFS or OS outcomes. Post hoc analysis of the pTisN0 patients revealed prolonged median PFS (104.5 vs. 139.9 months; P = 0.055) and OS (104.5 vs. 152.3 months; P = 0.091) outcomes similar to those for the pCR patients.

Conclusion

The absence of CIS on pretreatment TURBT in patients with MIUC undergoing NAC was associated with increased pCR rates, with no observed differences in PFS or OS. Isolated CIS at cystectomy was frequently observed, with lengthy PFS and OS durations similar to those for pCR patients. Further studies aimed at understanding the biology and clinical effect of CIS in MIUC are warranted.  相似文献   
992.
Traumatic brain injury (TBI) is a global problem with a huge socioeconomic impact. Current understanding of the pathophysiology of TBI has led to a systematic approach towards management in the pre-hospital, operating theatre and critical care settings. Early management is directed towards protecting the brain from secondary injury. TBI is a spectrum of diseases, and rapid radiological identification of the underlying pathology is paramount to determine appropriate surgical intervention. Perioperative management frequently requires neurocritical care, with most modern centres using intracranial pressure and cerebral perfusion pressure targeted therapies. Decompressive craniectomy can be a useful mechanism to control medically refractory intracranial hypertension and reduce mortality; however, it also results in a spectrum of outcome categories and remains a controversial topic. Finally, there is emerging evidence that TBI is a chronic illness, with increased incidence of cognitive and behavioural deficits, neurodegenerative disease and an increased mortality that extends well beyond the initial TBI stage.  相似文献   
993.
BACKGROUND: The purpose of this study was to evaluate 1) the incidence of hepatitis and its influence on the clinical management of and outcome in acute nonlymphoblastic leukemia (ANLL) patients in first complete remission and 2) the impact of routine hepatitis C virus screening on the incidence of hepatitis in these patients. STUDY DESIGN AND METHODS: Clinical and blood bank charts were reviewed for 65 consecutive ANLL patients between 1985 and 1993 who achieved complete remission after a course of daunomycin and cytarabine (cytarabine: 200 mg/m2/day × 7 days in continuous infusion; daunomycin: 60 mg/m2/day for the first 3 days of the 7, as a bolus). RESULTS: Only 43 percent of patients who developed hepatitis completed the scheduled therapy. Hepatitis did not decrease the probability of relapse (66 +/− 9% vs. 66 +/− 11%), but patients with changes in planned treatment, due to hepatitis or other causes, tended to have a higher relapse rate than patients without changes in consolidation therapy (56.5% vs. 40.4%; p = 0.10). This did not result in a decrease in disease-free survival, however, because of the higher number of treatment-related deaths in the patients without hepatitis (who completed the therapy). Over the period from 1985 through 1989, the 6-month actuarial probability of developing hepatitis was 42 percent. However, since 1989, when hepatitis C screening of blood donors was implemented, the incidence was reduced to 12.5 percent (p < 0.05), in spite of greater transfusion support (172 +/− 46 vs. 89 +/− 53, p < 0.01). No new cases of hepatitis were observed after the introduction of second-generation hepatitis C virus assays. CONCLUSION: Hepatitis precludes the use of consolidation therapy in about half of ANLL patients, resulting, in the experience described here, in a trend toward a higher rate of relapse. Hepatitis C virus screening of blood components reduces the incidence of hepatitis in ANLL patients.  相似文献   
994.
BACKGROUND: Reactive samples in hepatitis C virus (HCV) antibody screening of blood donors are currently referred for a confirmatory assay. This scheme is not optimally efficient and is expensive because of the lack of specificity and cost of confirmatory tests, as well as the need to discard false-positive donations. As in some human immunodeficiency virus antibody-confirmatory schemes, the safety and efficacy of confirming anti-HCV with two sequential screening assays were evaluated. STUDY DESIGN AND METHODS: Three combinations of two anti-HCV screening assays were used to test 75,874 blood donors. Results were compared with the routine testing scheme and HCV RNA detection in any enzyme immunoassay-repeatably reactive samples. RESULTS: The use of an alternative screening assay for repeat testing decreased the proportion of enzyme immunoassay-positive donors from 0.28 to 0.05 percent. All samples that were "confirmed" as positive by the standard combination of immunoassays and all HCV RNA-positive samples were detected by the sequential screening assays. No samples that had discordant results on primary and secondary screening assays were confirmed by recombinant immunoblot assay or were found to contain detectable HCV RNA. CONCLUSION: The combination of screening assays for anti-HCV confirmation was as safe as, cheaper than, and nearly as efficient as the standard testing scheme.  相似文献   
995.
Bovine high molecular weight kininogen (bHMWK) partially corrects the activated plasma thromboplastin time (aPTT) of Fitzgerald trait plasma which is congenitally deficient in HMWK. The relationship between the structure and activity of HMWK was clarified by studying the effects of different fragments of bHMWK on the aPTT of Fitzgerald-trait plasma. The peptides studied were lys-bradykinin-free HMWK, bradykinin-fragment 1-2-free HMWK, heavy chain, fragment 1-2-light chain, and light chain. All fragments were tested in equimolar concentrations. Bradykinin-fragment 1-2-free HMWK, heavy chain, and light chain have little or no correcting activity upon Fitzgerald-trait plasma aPTr. Fragment 1-2 light chain has the same correcting activity as intact bHMWK, while that of lys-bradykinin-free HMWK appears to be higher. Both fragment 1-2 and fragment 2 inhibit the clotting time of normal human plasma. When compared on a molar basis, fragment 2 is a more active inhibitor than fragment 1-2. When the effects of bovine plasma kallikrein upon bHMWK and hHMWK were studied, it was found that it released kinins from both kininogens. However, while the correcting activity of bHMWK was completely destroyed after 60 min of incubation, that of hHMWK was fully retained. These data suggest that: (a) the active part of bHMWK is comprised of the fragment 1-2 light chain portion; (b) fragment 1-2 or fragment 2 is the binding site to negatively charged surfaces, while the light chain interacts with other components of the surface-mediated reactions; and (c) bovine plasma kallikrein releases kinins, but probably does not cause the release of fragment 1-2 from human HMWK.  相似文献   
996.
L Carr  JA Pryor  ME Hodson 《Physiotherapy》1995,81(12):753-757
The literature suggests that self chest clapping (SCC) does not enhance rate of sputum clearance if combined with the active cycle of breathing techniques (ACBT), but many patients find SCC beneficial and continue to use it. Previous studies have examined the effects of assisted chest clapping on oxygen saturation (SaO2), but what would be the effects of SCC on SaO2? It was important to establish any possible detrimental effects from its use and to explore the views of patients using it as part of their treatment.

The SaO2 was measured in 20 clinically stable patients with cystic fibrosis during their physiotherapy (the ACBT with SCC in a gravity assisted position) and all patients completed a short anonymous questionnaire to obtain their views on SCC. Patient characteristics of lung function, arterial blood gases, response to bronchodilator therapy, 24-hour sputum weight and exercise ability were recorded, within 48 hours of participation within the study, to identify a possible relationship between these and a change in SaO2.

In the group as a whole there was a statistically significant mean fall in SaO2 with SCC (p = 0.026). However, this fall was never greater than 4.4%. In some patients a fall in SaO2 was recorded with SCC, but in others there was an increase. There was no correlation between the variables measured and a fall in SaO2 with SCC. The patients using SCC had strong views and beliefs about why they did so.  相似文献   

997.
Accumulation of eosinophils in the airways is characteristic of allergic rhinitis and asthma. The tissue eosinophilia may involve both recruitment of mature eosinophils and proliferation of their progenitors. This study examines mature eosinophils (nasal and circulating), their circulating progenitors, and a potential role of granulocyte-macrophage colony-stimulating factor (GM-CSF) in stimulating these progenitors. Twelve subjects with a history of seasonal allergic rhinitis and positive skin prick test for birch pollen were studied during four periods: shortly before, in the early and intense phase, at the end, and well after the Swedish birch-pollen season. Nasal mucosal and circulating eosinophils were examined in both nasal brushings and peripheral blood samples. Eosinophil/basophil progenitors were determined by counting colony-forming units in nonadherent mononuclear blood-cell cultures in methylcellulose at 14 days. The nasal mucosal cytokines GM-CSF, interleukin (IL)-1beta, IL-3, IL-5, IL-6, IL-8, and RANTES were analyzed (ELISA) in nasal lavage (NAL) fluids. All patients developed severe symptoms of rhinitis at the height of the season, with increased numbers of eosinophils in the nasal mucosa (P<0.05) and in the circulation (P<0.05). At this time point, the number of circulating progenitors (P<0.05) and the NAL fluid level of GM-CSF (P<0.05) were also increased. In contrast, there was no change in the NAL fluid levels of IL-1beta, IL-3, IL-6, or IL-8. Neither IL-5 nor RANTES could be detected in any of the NAL fluids. At the end of or after the season, there was no increase in nasal eosinophils or circulating eosinophils or progenitors (P>0.05). Ex vivo addition of GM-CSF (10-100 U) increased the number of blood progenitors grown before (P<0.01) and after (P<0.05) the season, compared with during the season. The in vitro GM-CSF responsiveness of progenitors may be related to whether or not these already have been stimulated endogenously by GM-CSF. Taken together, our data thus suggest that GM-CSF may play a role in vivo to increase production of eosinophilic progenitors in allergic airway disease.  相似文献   
998.
目的分析创伤性动静脉瘘(AVF)的临床特点、造影表现、造影技术及治疗方式的选择。方法回顾性分析纽约Kings County医疗中心25年间全部确诊的108例创伤性AVF的介入相关诊疗资料。分析内容包括患者外伤种类、临床表现、损伤部位、血管造影异常特征、AVF血流动力学特征(分5个类型)、治疗方式的选择等。结果 108例患者中共发现117处AVF,大多数患者临床特征不明确。创伤种类包括枪伤(导致72处AVF)、刺伤(24处)、钝性伤(8处)、高处坠落伤(3处)、医源性损伤(2处)。损伤部位常见于肢体(46例)、颈部(19例)、肝脏(13例)和锁骨下血管(11例)。所有病变均可见静脉早显,显示动脉横断52处,撕裂37处,49.6%的AVF与假性动脉瘤有关。最常见的血流特点是Ⅰ型,即瘘口所在的动脉近段和远段、静脉的近段和远段都显示,伴远侧段静脉瓣功能不全,共40处瘘(34.2%),其次是Ⅲ型22个(18.8%),Ⅴ型最不常见(4.3%)。34例接受手术治疗,61例栓塞治疗,7例临床观察。分别采用弹簧圈(47例)、明胶海绵(9例)、无水乙醇(3例)、可脱球囊(2例),其中弹簧圈效果理想、并发症少。6例采用覆膜支架效果好。结论血管造影是诊断创伤性AVF的金标准,造影时准确观察动脉损伤的性质,瘘口的解剖和血流特点及所有进入瘘口的动脉分支,对于选择治疗方式及保证介入治疗的成功完成至关重要。  相似文献   
999.

Background  

Frailty is highly prevalent in older people. Its serious adverse consequences, such as disability, are considered to be a public health problem. Therefore, disability prevention in community-dwelling frail older people is considered to be a priority for research and clinical practice in geriatric care. With regard to disability prevention, valid screening instruments are needed to identify frail older people in time. The aim of this study was to evaluate and compare the psychometric properties of three screening instruments: the Groningen Frailty Indicator (GFI), the Tilburg Frailty Indicator (TFI) and the Sherbrooke Postal Questionnaire (SPQ). For validation purposes the Groningen Activity Restriction Scale (GARS) was added.  相似文献   
1000.
目的:测定人血清脱金属铁传递蛋白裂解焦磷酸键的反应速率常数.方法:应用31P NMR技术,在不同pH值及不同浓度MgCl2存在条件下,测定了脱金属铁传递蛋白与焦磷酸二钠反应的核磁共振图谱,根据焦磷酸盐的摩尔浓度(对应于其谱峰强度)随时间的变化情况,应用动力学公式对数据进行拟合.结果:当人血清脱金属铁传递蛋白(0.5~1.0 mmol/L)与焦磷酸盐的反应摩尔浓度比为15时,在312 K条件下,反应速率常数分别为:8.83×10-4 L·mmol-1·h-1(pH 6.85)、9.59×10-4 L·mmol-1·h-1(pH 7.40)和1.38×10-3 L·mmol-1·h-1(pH 8.15).在2 mmol/L MgCl2存在时,pH 7.40、312 K条件下,反应速率常数为1.21×10-3L·mmol-1·h-1.结论:人血清脱金属铁传递蛋白能缓慢地将焦磷酸根裂解为磷酸根,反应具有二级反应动力学性质,Mg2 对该裂解反应有弱催化作用.  相似文献   
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