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91.
OBJECTIVE: Our purpose was to examine the impact of the introduction of endovascular treatment on the early outcomes of ruptured abdominal aortic aneurysms (AAAs) during 2 consecutive time periods at a single institution. METHODS: The hospital records of a single tertiary care center from 1997 to 2004 were retrospectively reviewed, and 36 consecutive patients who underwent treatment for acute ruptured AAA were identified. They were divided into 19 (53%) patients who were all treated with conventional open surgery from 1997 to 2001 (early) and 17 (47%) patients who were treated either with open (n = 4, 24%) or endovascular (n = 13, 76%) methods from 2002 to 2004 (late). All endovascular repairs were performed with commercially available bifurcated devices. Outcome measures included death, major complications, disposition at discharge (home or extended care facility), procedure time, blood loss, and hospital length of stay. RESULTS: Age, sex, and AAA size were similar between the 2 groups. Perioperative mortality in the early and late periods were 37% versus 12%, respectively (P =.13); rates of major complications were 84% versus 65%, respectively (P =.26); and discharge to home rather than extended care facility was 32% versus 59%, respectively (P =.18). Median procedure times (275 vs 149 minutes, P <.01), blood loss (3800 vs 138 mL, P <.0001), and length of stay (18 vs 6 days, P <.05) were all higher during the early period than in the late period. CONCLUSIONS: This preliminary study suggests that introduction of endovascular therapies may be potentially beneficial in the overall treatment scheme of patients with ruptured AAAs. However, longer follow-up and larger cohorts are needed to better establish its feasibility and efficacy compared with conventional open surgical repair.  相似文献   
92.
OBJECTIVE: We evaluated the ability of neuromonitoring to predict postoperative outcome in patients undergoing thyroid surgery for different indications. SUMMARY BACKGROUND DATA: Neuromonitoring has been advocated to reduce the risk of vocal cord palsy and to predict postoperative vocal cord function. METHODS: Three hundred twenty-eight patients (502 nerves at risk) were studied prospectively at a single center. Neuromonitoring was performed with the Neurosign 100 device by transligamental placement of the recording electrode into the vocalis muscles. Cumulative distribution of stimulation thresholds was determined by stepwise decreases in current (1 mA to 0.05 mA) for both the vagus and the recurrent nerve. Patients were grouped according to surgical risk (benign and malignant disease, reoperation for benign and for malignant disease). RESULTS: If the electrophysiological response was correlated to postoperative vocal cord function, the sensitivity of neuromonitoring was modest (86% in surgery for benign disease) to low (25% in reoperation for malignant disease); the positive predictive value was modest (overall rate 62%) but acceptable (87%) if corrected for technical problems. Specificity and negative predictive values were high (ie, overall >95%). Stimulation thresholds were not augmented in 11 patients, in whom postoperative palsy developed despite normal intraoperative recordings. Similarly, an electrical field response was elicited in 14 of 21 patients with preoperative vocal cord palsy. Electromyographic recordings did not reveal an abnormal amplitude or a decline in nerve conduction velocity. CONCLUSIONS: Neuromonitoring is useful for identifying the recurrent laryngeal nerve, in particular if the anatomic situation is complicated by prior surgery, large tissue masses, aberrant nerve course. However, neuromonitoring does not reliably predict postoperative outcome.  相似文献   
93.
Review of 125 SiteSelect stereotactic large-core breast biopsy procedures   总被引:1,自引:0,他引:1  
Advances in stereotactic breast biopsies have introduced a variety of devices that yield different sizes of tissue samples. The choice of biopsy device should be based on which technique is most likely to yield a definitive diagnosis at the time of the initial biopsy. This is a prospective study of 104 patients who underwent a total of 125 stereotactic breast biopsies using the SiteSelect large-core biopsy device. From May 1999 to June 2001, 104 patients underwent 125 stereotactic breast biopsies with the SiteSelect large-core biopsy device. One hundred four 15 mm SiteSelect biopsies, eighteen 10 mm SiteSelect biopsies, and three 22 mm SiteSelect biopsies were performed. Atypical ductal hyperplasia (ADH) and ductal carcinoma in situ (DCIS) were found in 15% of the biopsies and infiltrating cancer was found in another 15% of the biopsies. Seventy-eight percent of the ADH and 90% of the DCIS lesions were associated with indeterminate calcifications noted on mammogram. Two of the 22 mm SiteSelect excisions yielded a specimen that contained the entire cancer with clear surgical margins. All of the patients with DCIS or invasive carcinoma underwent definitive surgical and adjuvant therapy. The sensitivity and specificity of SiteSelect in this series of patients was 100%. The SiteSelect biopsy procedure is safe, well tolerated by patients, and can be performed under local anesthesia. SiteSelect is comparable to an open excisional biopsy in its ability to obtain adequate tissue for accurate diagnosis, but excises significantly less normal surrounding breast tissue. Based on the data, indications for primary use of SiteSelect are indeterminate calcifications on mammogram, rebiopsy of a vacuum-assisted biopsy site that yielded atypia on pathologic examination, and complete excision of a lesion suspicious for invasive carcinoma in order to assess actual size and margin status.  相似文献   
94.
Summary The proliferation of the human promonocytic leukemia cell line U937 is inhibited by several ether lipids, ether lipid analogues and by phorbol esters. An early effect of this retardation of cell growth is the induction of a basic chromosomal protein, histone H10. Northern blot analysis of H10 mRNA levels reveals an increase of the mRNA concentration within a few hours after addition of hexadecylphosphocholine and 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine. This early effect on the synthesis of a subtype of H1 proteins precedes the expression of several parameters of the monocytic differentiation of U937 cells.Abbreviations ES-16-OH 1-O-palmitoyl-sn-glycero-3-phosphocholine - ET-18-OCH3 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine - He-PC hexadecylphosphocholine - TPA 12-O-tetraclecanoylphorbol 13-acetate - He-PC6 hexadecylphospho(N,N,N-trimethylamino)-hexanol Dedicated to Professor Dr. D. Schmähl on the occasion of his 65th birthdaySupported by the Deutsche Forschungsgemeinschaft (D.D.) and the Ministry for Research and Technology (C.U.)  相似文献   
95.
Cell‐matrix interactions constitute a fundamental aspect of skeletal cell biology and play essential roles in bone homeostasis. These interactions are primarily mediated by transmembrane integrin receptors, which mediate cell adhesion and transduce signals from the extracellular matrix to intracellular responses via various downstream effectors, including integrin‐linked kinase (ILK). ILK functions as adaptor protein at focal adhesion sites, linking integrins to the actin cytoskeleton, and has been reported to act as a kinase phosphorylating signaling molecules such as GSK‐3β and Akt. Thereby, ILK plays important roles in cellular attachment, motility, proliferation and survival. To assess the in vivo role of ILK signaling in osteoprogenitors and the osteoblast lineage cells descending thereof, we generated conditional knockout mice using the Osx‐Cre:GFP driver strain. Mice lacking functional ILK in osterix‐expressing cells and their derivatives showed no apparent developmental or growth phenotype, but by 5 weeks of age they displayed a significantly reduced trabecular bone mass, which persisted into adulthood in male mice. Histomorphometry and serum analysis indicated no alterations in osteoclast formation and activity, but provided evidence that osteoblast function was impaired, resulting in reduced bone mineralization and increased accumulation of unmineralized osteoid. In vitro analyses further substantiated that absence of ILK in osteogenic cells was associated with compromised collagen matrix production and mineralization. Mechanistically, we found evidence for both impaired cytoskeletal functioning and reduced signal transduction in osteoblasts lacking ILK. Indeed, loss of ILK in primary osteogenic cells impaired F‐actin organization, cellular adhesion, spreading, and migration, indicative of defective coupling of cell‐matrix interactions to the cytoskeleton. In addition, BMP/Smad and Wnt/β‐catenin signaling was reduced in the absence of ILK. Taken together, these data demonstrate the importance of integrin‐mediated cell‐matrix interactions and ILK signaling in osteoprogenitors in the control of osteoblast functioning during juvenile bone mass acquisition and adult bone remodeling and homeostasis. © 2017 American Society for Bone and Mineral Research.  相似文献   
96.

Introduction and hypothesis

To prospectively evaluate the use of a particular polypropylene Y mesh for robotic sacrocolpopexy.

Methods

This was a prospective study of 120 patients who underwent robotic sacrocolpopexy. We compared preoperative and 12-month postoperative objective and subjective assessments via the Pelvic Organ Prolapse Quantification (POP-Q), the Pelvic Floor Distress Inventory, Short Form 20 (PFDI-20); the Pelvic Floor Impact Questionnaire, Short Form 7 (PFIQ-7); and the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire 12 (PISQ-12). Objective “anatomical success” was defined as POP-Q stage 0 or 1 at all postoperative intervals. We further defined “clinical cure” by simultaneously considering POP-Q points and subjective measures. To be considered a “clinical cure,” a given patient had to have all POP-Q points ≤0, apical POP-Q point C ≤5, no reported pelvic organ prolapse symptoms on the PFDI-20, and no reoperation for prolapse at all postoperative intervals.

Results

Of the 120 patients, 118 patients completed the 1-year follow-up. The objective “anatomical success” rate was 89 % and the “clinical cure” rate was 94 %. The PFDI-20 mean score improved from 100.4 at baseline to 21.0 at 12 months (p?<?0.0001); PFIQ-7 scores improved from 61.6 to 8.0 (p?<?0.0001); and PISQ-12 scores improved from 35.7 to 38.6 (p?<?0.0009). No mesh erosions or mesh-related complications occurred.

Conclusion

The use of this ultra-lightweight Y mesh for sacrocolpopexy, eliminated the mesh-related complications in the first postoperative year, and provided significant improvement in subjective and objective outcomes.  相似文献   
97.
Background: Individuals living with spinal cord injury (SCI) have a high prevalence of obesity and unique barriers to healthy lifestyle. Objective: To examine barriers and facilitators to engagement and weight loss among SCI participants enrolled in the Group Lifestyle Balance Adapted for individuals with Impaired Mobility (GLB-AIM), a 12-month intensive lifestyle intervention. Methods: SCI participants (N = 31) enrolled in a wait-list, randomized controlled trial where all participants received intervention between August 2015 and February 2017. Analyses of pooled data occurred in 2020 to examine cross-sectional and prospective associations of hypothesized barriers and facilitators with (1) intervention engagement, comprised of attendance and self-monitoring, and (2) percent weight change from baseline to 12 months. We performed multivariable linear regression on variables associated with outcomes at p < .05 in bivariate analyses and controlled for intervention group. Results: Participants were middle-aged (mean age, 48.26 ± 11.01 years), equally male (50%) and female, White (80.7%), and unemployed (65.6%). In participants who completed baseline surveys (n = 30), dietary self-efficacy explained 26% of variance in engagement (p < .01); among the 12-month study completers (n = 22, 71.0%), relationship issues explained 23% of variance in engagement (p < .01). Money problems, health issues unrelated to SCI, lack of motivation, and experimental group explained 57% of variance in weight loss (p for model < .01), with lack of motivation uniquely explaining 24% of variance (p < .01). Conclusion: Improving engagement and weight loss for persons with SCI in the GLBAIM program may be achieved by addressing lack of motivation, relationship issues, and nutrition self-efficacy.  相似文献   
98.
We delineated the achievement of early speech-language milestones in 15 young children with Rett syndrome (MECP2 positive) in the first two years of life using retrospective video analysis. By contrast to the commonly accepted concept that these children are normal in the pre-regression period, we found markedly atypical development of speech-language capacities, suggesting a paradigm shift in the pathogenesis of Rett syndrome and a possible approach to its early detection.  相似文献   
99.

Background

Respiratory insufficiency occurs in 20 % of Guillain–Barré syndrome (GBS) patients, and the duration of mechanical ventilation (MV) ranges widely. We identified predictors of prolonged MV to guide clinical decision-making on tracheostomy.

Methods

We analyzed prospectively collected data from 552 patients with GBS in the context of two clinical trials and three cohort studies in The Netherlands. Potential predictors for prolonged MV, defined as duration of ≥14 days, were considered using crosstabs. Selected predictors were analyzed using Cox regression analysis.

Results

On a total of 150 (27 %) patients requiring MV, 106 (71 %) patients needed prolonged MV. The median duration of MV was 28 days (Interquartile Range [IQR] 12–60 days). The strongest observed predictors of prolonged MV were muscle weakness and axonal degeneration or unexcitable nerves on nerve conduction studies. Patients who are unable to lift the arms from the bed (bilateral Medical Research Council [MRC] of deltoid muscles of 0–2) at 1 week after intubation have an 87 % chance to require prolonged MV versus 69 % in patients who are able to lift the arms from the bed (bilateral MRC of deltoid muscles of 3–10). Patients in this last group who had axonal degeneration or unexcitable nerves on nerve conduction studies also have a 90 % chance to require prolonged MV.

Conclusions

Ventilated GBS patients who are unable to lift the arms from the bed and patients who have axonal degeneration or unexcitable nerves at 1 week are at high risk of prolonged MV, and tracheostomy should be considered in these patients.
  相似文献   
100.
Prosopagnosia is currently viewed within the constraints of two competing theories of face recognition, one highlighting the analysis of features, the other focusing on configural processing of the whole face. This study investigated the role of feature analysis versus whole face configural processing in the recognition of facial expression. A prosopagnosic patient, SC made expression decisions from whole and incomplete (eyes-only and mouth-only) faces where features had been obscured. SC was impaired at recognizing some (e.g., anger, sadness, and fear), but not all (e.g., happiness) emotional expressions from the whole face. Analyses of his performance on incomplete faces indicated that his recognition of some expressions actually improved relative to his performance on the whole face condition. We argue that in SC interference from damaged configural processes seem to override an intact ability to utilize part-based or local feature cues.  相似文献   
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