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991.
992.
C1-C2 transarticular screw fixation for atlantoaxial instability   总被引:4,自引:0,他引:4  
OBJECTIVES: The atlantoaxial segment of the cervical spine is commonly destabilized in a variety of disorders. Transarticular screw fixation of the C1-C2 joint has been proposed as a biomechanically superior therapeutic modality. The authors present their experience with this technique. METHODS: A retrospective analysis of 23 patients treated with this technique was performed. The mean follow-up period was 39.5 +/- 0.1 months. RESULTS: Mean duration of hospitalization was 3.4 +/- 0.1 days (range, 2 to 11 days). No intraoperative or early postoperative complications were detected. Four patients (17.4%) had postoperative complications unrelated to the primary procedure. The position of the screw was judged as satisfactory in 21 patients (91.3%). Two patients (8.7%) with suboptimal positioning of the screws were neurologically intact but needed no reoperation. Solid osseous fusion was detected in 19 patients (82.6%). CONCLUSIONS: Transarticular C1-C2 screw fixation appears to be a safe and surgically reliable technique. Criteria for its application and refinements in its technical considerations continue to advance its clinically versatile therapeutic potential.  相似文献   
993.
994.
The purpose of our study was assessment of the relative contribution of the systems involved in blood gas exchange to the limited exercise capacity in patients with β-thalassemia major (TM) using integrative cardiopulmonary exercise testing (CPET) with estimation of oxygen kinetics. The study consisted of 15 consecutive TM patients and 15 matched controls who performed spirometric evaluation, measurement of maximum inspiratory pressure (Pimax) and an incremental symptom-limited CPET on a cycle ergometer. Exercise capacity was markedly reduced in TM patients as assessed by peak oxygen uptake (pVO2, mL/kg/min: 22.1±6.6 vs 33.8±8.3; P <0.001) and anaerobic threshold (mL/kg/min: 13.0±3.0 vs 18.7±4.6; P <0.001) compared with controls. No ventilatory limitation to exercise was noted in TM patients (VE/VCO2 slope: 23.4±3.2 vs 27.8±2.6; P <0.001 and breathing reserve, %: 42.9±17.0 vs 29.5±12.0; P <0.005) and no difference in oxygen cost of work (peak VO2/WR, mL/min W: 12.2±1.7 vs 12.2±1.5; P =NS). Delayed recovery oxygen kinetics after exercise was observed in TM patients (VO2/ t slope, mL/kg/min2: 0.67±0.27 vs 0.93±0.23; P <0.05) that was significantly correlated with Pimax at rest ( r : 0.81; P <0.001). The latter was also significantly correlated to pVO2 ( r : 0.84; P <0.001) and inversely correlated to ferritin levels ( r : −0.6; P <0.02). Exercise capacity is markedly reduced in TM patients and this reduction is highly associated with the limited functional status of peripheral muscles.  相似文献   
995.
BACKGROUND: Massive vulvar edema in a woman with preeclampsia preceded the development of massive ascites and impending eclampsia. CASE: A 17-year-old preeclamptic, primiparous woman was admitted with preeclampsia and massive vulvar edema. Other causes were excluded. The vulvar edema increased as the blood pressure and ascites increased, and a severe headache developed. Cesarean section for increasing preclampsia was performed. In the puerperium, the blood pressure improved and vulvar edema resolved. The clinical picture of the vulvar edema correlated with the severity of the preeclampsia. CONCLUSION: The presence of vulvar edema in women with preeclampsia should indicate immediate admission to the hospital. These patients must be considered as at high risk, and close monitoring must be instituted. In our case, vulvar edema preceded massive ascites development. We assume a common development mechanism for these signs in preeclampsia, due mainly to increased capillary permeability and hypoalbuminemia. The attending physician must be prepared for immediate delivery and possible preeclampsia complications in these patients.  相似文献   
996.
An invertebrate intestinal mucin gene, AgMuc1, was isolated from the malaria vector mosquito Anopheles gambiae. The predicted 122-residue protein consists of a central core of seven repeating TTTTVAP motifs flanked by hydrophobic N- and C-terminal domains. This structure is similar to that of mucins that coat the protozoan parasite Trypanosoma cruzi. Northern blot analysis indicated that the gene is expressed exclusively in the midgut of adult mosquitoes. A length polymorphism and in situ hybridization were used to genetically and cytogenetically map AgMuc1 to division 7A of the right arm of the second chromosome. The subcellular localization of the encoded protein in tissue culture cells was examined by using a baculovirus vector to express AgMuc1 protein tagged with the green fluorescent protein (GFP). The results indicated that this protein is found at the cell surface and that both hydrophobic domains are required for cell surface targeting. We propose that AgMuc1 is an abundant mucin-like protein that lines the surface of the midgut microvilli, potentially protecting the intestinal epithelium from the proteinase-rich environment of the gut lumen. An intriguing possibility is that, as an abundant surface protein, AgMuc1 may also interact with the malaria parasite during its invasion of the mosquito midgut.  相似文献   
997.
As part of a needs analysis preceding the development of an e-learning platform on infection prevention, European intensive care unit (ICU) nurses were subjected to a knowledge test on evidence-based guidelines for preventing ventilator-associated pneumonia (VAP). A validated multiple-choice questionnaire was distributed to 22 European countries between October 2006 and March 2007. Demographics included nationality, gender, ICU experience, number of ICU beds and acquisition of a specialised degree in intensive care. We collected 3329 questionnaires (response rate 69.1%). The average score was 45.1%. Fifty-five percent of respondents knew that the oral route is recommended for intubation; 35% knew that ventilator circuits should be changed for each new patient; 38% knew that heat and moisture exchangers were the recommended humidifier type, but only 21% knew that these should be changed once weekly; closed suctioning systems were recommended by 46%, and 18% knew that these must be changed for each new patient only; 51% and 57%, respectively, recognised that subglottic drainage and kinetic beds reduce VAP incidence. Most (85%) knew that semi-recumbent positioning prevents VAP. Professional seniority and number of ICU beds were shown to be independently associated with better test scores. Further research may determine whether low scores are related to a lack of knowledge, deficiencies in training, differences in what is regarded as good practice, and/or a lack of consistent policy.  相似文献   
998.
The aim of the study is to describe the evolution of contraceptive and sexual behavior within our Greek society. MATERIALS, MEASURES AND METHODS: We interviewed 508 females and made a statistical analysis of their answers. CONCLUSION: We tried to underline a strategy for the best promotion of the values in question. General, sexual and contraceptive education as well as the use and type of contraception are the weapons that will lead our endeavors to decreased involuntary pregnancy and towards responsible sexual behavior.  相似文献   
999.
Waldenström macroglobulinemia (WM) is a B-cell lymphoproliferative disorder characterized by lymphoplasmacytic bone marrow infiltration and immunoglobulin M (IgM) monoclonal gammopathy. It remains incurable, with a median survival of 5-10 years in symptomatic WM. Current first-line treatment options include alkylating agents, nucleoside analogues, and rituximab-based therapies. However, primary or secondary resistance invariably develops. Thus, new treatment options are needed. Preclinical studies have shown that the proteasome inhibitor bortezomib targets signaling pathways of relevance in WM. Bortezomib, alone and in combination with rituximab, has demonstrated notable activity in clinical studies in patients with WM, predominantly in phase II trials in the relapsed or refractory setting. In newly diagnosed patients, bortezomib plus rituximab and dexamethasone is highly active (complete response/near-complete response = 22%). Bortezomib-based therapies result in rapid responses, potentially making them suitable treatment options for patients with hyperviscosity-related symptoms who require a rapid reduction in IgM level. In addition, bortezomib appears unique in reducing rituximab-associated IgM flares. Bortezomib is generally well tolerated in WM. However, neurotoxicity is common and might be the cause of dose reduction or treatment discontinuation. Bortezomib has no adverse effect on stem cell harvesting and engraftment, making it a feasible treatment option in transplantation-eligible patients. These encouraging data have led to the inclusion of bortezomib as a salvage treatment option in the recently updated Fourth International Workshop on Waldenström's Macroglobulinemia treatment recommendations.  相似文献   
1000.

BACKGROUND:

In patients with multiple myeloma, renal impairment (RI) at the time of diagnosis is associated with poor survival. To the authors' knowledge, the current retrospective analysis presented is the first to assess the impact of various degrees of renal dysfunction on safety and efficacy outcomes in a large cohort of patients with relapsed and/or refractory multiple myeloma who received treatment with lenalidomide plus dexamethasone.

METHODS:

Three hundred fifty‐three patients from 2 large phase 3 trials were randomized to receive lenalidomide (25 mg) plus dexamethasone (40 mg). For the purpose of this analysis, RI was defined according to the calculated creatinine clearance (CLCr) level as follows: mild or no RI (CLCr ≥ 60 mL/minute), moderate RI (CLCr from ≥ 30 mL/minute to <60 mL/minute), and severe RI (CLCr <30 mL/minute).

RESULTS:

The RI subgroups did not differ significantly in terms of the overall response rate (range, 50%‐64%) or response quality (very good partial response or better, 27%‐37%). In all RI subgroups, the time to progression and progression‐free survival did not differ significantly compared with the mild or no RI group. Patients with RI experienced an increased incidence of thrombocytopenia, required more frequent lenalidomide dose reduction or interruption, and had shorter overall survival than patients with mild or no RI (P = .006). Lenalidomide plus dexamethasone led to improvement in renal function in the majority of patients.

CONCLUSIONS:

The results from this study indicated that, with careful monitoring of the CLCr level and adverse events as well as appropriate dose adjustments, lenalidomide plus dexamethasone is an effective and well tolerated treatment option for patients with multiple myeloma who have RI. Cancer 2010. © 2010 American Cancer Society.  相似文献   
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