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1.
BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) was introduced 50 years ago. The Lumbar I/F cage (DePuy Spine, Raynham, MA) was designed to enhance PLIF results. PLIF with the Lumbar I/F cage and posterior Variable Screw Placement System (VSP) has increased the success of fusion to nearly 100% at the four lowest lumbar levels, L2-L3 through L5-S1. Less commonly, PLIF is indicated for the L1-L2 level. Clinical-results of Lumbar I/F cage fusion and VSP at L1-L2 have-not been reported. PURPOSE: The purpose of this study is to report the functional outcomes, fusion rate, and complications related to PLIF with Lumbar I/F cage and VSP of L1-L2 STUDY DESIGN/SETTING: The setting is a retrospective, single-arm cohort study of consecutive PLIF surgical patients at a single center. PATIENT SAMPLE: A review of 373 of 425 patients who underwent PLIF with Lumbar I/F cage and VSP from 1999 to 2002 identified 12 patients who had PLIF with Lumbar I/F cage and VSP at L1-L2. Mean follow-up was 31 months (range 12-65 months). OUTCOME MEASURES: Clinical success was determined with a modified Prolo score evaluating pain, function, medication usage and economic status. Fusion success, determined by evaluation of plain radiographs, was defined by continuous bone bridging the fusion area with no lucencies. METHODS: The 12 patients were evaluated for clinical success and/fusion success at last follow-up. These results were compared with the results of the 373 patients reviewed, and historical groups of the original Investigational Device Exemption study and the 10-year follow-up study. RESULTS: Previous surgery was reported by 10 of 12 patients, with an average symptom-free period of 3 years after previous fusion and before presentation with severe symptomatology necessitating further surgery at L1-L2. Seven patients had clinical success (59%), and five patients were clinically unsuccessful (41%). This included zero excellent, 2 of 12 (15%) good, 5 of 12 (42%) fair, and 5 of 12 (42%) poor results. Fusion was successful in seven (58%) and failed in five patients (42%). Three failed fusions were associated with L1-L2 subsidence. Two patients required further revision for non-union. CONCLUSIONS: In 12 patients with L1-L2 fusion, we report an unexpected high rate of failed fusion and poor clinical outcome.  相似文献   
2.
Joshi S  Pleij CW  Haenni AL  Chapeville F  Bosch L 《Virology》1983,127(1):100-111
The existence of subgenomic RNAs is well established in the case of plant viruses such as tobacco mosaic virus (TMV). However, except for the subgenomic coat protein mRNA, it is not known whether the other subgenomic RNAs have a function in the life cycle of the virus. In search of more information about one of the major subgenomic RNAs-intermediate length RNA-2 or I2 RNA-of TMV, in vitro and in vivo translational studies were performed. The I2 RNA, which codes in vitro for the synthesis of a 30K (K = kilodalton) protein, appears to be uncapped as judged by the need of different in vitro translation conditions for the synthesis of this protein, compared to the conditions required for the synthesis of the 126K and 183K proteins coded by the capped genomic RNA. In vivo a protein migrating in the same position as the 30K protein synthesized in vitro can be detected in infected tobacco leaves. Since this protein occurs transiently early upon infection, whether it is virus-coded or virus-induced, it could have an early function during infection.  相似文献   
3.
BackgroundLow serum magnesium levels predict cardiovascular and all-cause mortality in patients with typ 2 diabetes.SettingOutpatient clinic of obesity and central hospital.ObjectivesTo assess long-term alterations in circulating magnesium status after Roux-en-Y gastric bypass (RYGB) surgery and associations with remission of type 2 diabetes (T2D).MethodsRetrospective analysis of 5-year outcomes of plasma magnesium (p-Mg) and glucometabolic statuses in patients who underwent primary RYGB and who completed the annual follow-up program. Data were investigated from 84 patients without diabetes and 62 with T2D before RYGB, who showed either prolonged remission (n = 30), temporary remission (n = 16), or no remission (n = 16) after surgery.ResultsBody mass indexes before RYGB were similar in patients with and without T2D, irrespective of remission. The patients not achieving remission showed longer diabetes durations; higher circulating glucose levels; more intensive antidiabetic drug treatment, including insulin; and significantly lower p-Mg concentrations (.73 [±.08] mmol/L compared with .80–.82 [±.07] mmol/L, respectively; P < .01) than the groups showing remission or without diabetes before surgery. After RYGB, the p-Mg increased similarly, by 10–12% in the groups with T2D before surgery, irrespective of remission; however, the nonremission group did not reach the p-Mg levels registered in the other groups after follow-up. The nonremission group reached .82 (.09) mmol/L, compared with .87 (.06) and .88 (.08) mmol/L (P < .05), respectively, in patients with remission or without a history of diabetes.ConclusionThe p-Mg concentrations increased after RYGB, with similar increments irrespective of T2D remission; however, the nonremission group started from an inferior level and did not reach the p-Mg concentrations seen in the groups achieving remission or without a history of diabetes before surgery.  相似文献   
4.
The association between change in glucose metabolism and change in skeletal muscle magnesium (Mg) concentration induced by antihypertensive treatment was evaluated in 37 patients with essential hypertension randomly treated with either lisinopril or bendrofluazide. Before and after 6 months of treatment, skeletal muscle biopsies were performed, glucose tolerance was determined by oral (OGTT) and intravenous glucose tolerance tests (IVGTT), and insulin sensitivity was assessed by the hyperinsulinemic euglycemic clamp technique. An inverse relationship was found between the treatment-induced change in fasting plasma glucose concentration and change in skeletal muscle Mg concentration (r = -0.39, P < .05). However, there was no significant correlation between skeletal muscle Mg content and either insulin sensitivity measured by the hyperinsulinemic euglycemic clamp test or glucose tolerance evaluated by IVGTT and OGTT. In conclusion, an increased circulating glucose concentration was correlated with a decreased Mg concentration in skeletal muscle during antihypertensive treatment. However, the Mg concentration in skeletal muscle did not significantly predict the insulin sensitivity or glucose tolerance.  相似文献   
5.

Purpose  

The maintenance of an obtained lower weight level is often found to be difficult. The aim of this study was to determine weight maintenance after an initial weight loss by consumption of a meal replacement with a vegetable-oil emulsion associated with prolonged satiety.  相似文献   
6.
The Potyvirus helper component-proteinase (HC-Pro) binds nonspecifically to single-stranded nucleic acids with a preference for RNA. To delineate the regions of the protein responsible for RNA binding, deletions were introduced into the full-length Potato potyvirus Y HC-Pro gene carried by an Escherichia coli expression vector. The corresponding proteins were expressed as fusions with the maltose-binding protein, purified, and assayed for their RNA-binding capacity. The results obtained by UV cross-linking and Northwestern blot assays demonstrated that the N- and C-terminal regions of HC-Pro are dispensable for RNA binding. They also revealed the presence of two independent RNA-binding domains (designated A and B) located in the central part of HC-Pro. Domain B appears to contain a ribonucleoprotein (RNP) motif typical of a large family of RNA-binding proteins involved in several cellular processes. The possibility that domain B consists of an RNP domain is discussed and suggests that HC-Pro could constitute the first example of a plant viral protein belonging to the RNP-containing family of proteins.  相似文献   
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Glucocorticoids are often applied in neonatology and perinatology to fight the problems of respiratory distress and chronic lung disease. There are, however, many controversies regarding the adverse side effects and long-term clinical benefits of this therapeutic approach. In rats, glucocorticoids are known to seriously impair the formation of alveoli when applied during the first two postnatal weeks even at very low dosage. The current study investigates short-term and long-term glucocorticoid effects on the rat lung by means of morphologic and morphometric observations at light and electron microscopic levels. Application of a high-dosage protocol for only few days resulted in a marked acceleration of lung development with a precocious microvascular maturation resulting in single capillary network septa in the first 4 postnatal days. By postnatal d 10, the lung morphologic phenotype showed a step back in the maturational state, with an increased number of septa with double capillary layer, followed by an exceptional second round of the alveolarization process. As a result of this process, there was an almost complete recovery in the parenchymal lung structure by postnatal d 36, and by d 60, there were virtually no qualitative or quantitative differences between experimental and control rats. These findings indicate that both dosage and duration of glucocorticoid therapy in the early postnatal period are very critical with respect to lung development and maturation and that a careful therapeutic strategy can minimize late sequelae of treatment.  相似文献   
10.
AIM: To validate whether quantitative flow-cytometric analysis of particulate matter in urine would allow for accurate and rapid enumeration of red blood cells (RBC), leukocytes (WBC), squamous epithelial cells (EC), casts, and bacteria, a Sysmex UF-100 analyzer was tested in a multicenter study. MATERIAL AND METHODS: At first, reference values were established and found to be < 14 for RBC, < 16 for WBC, < 9 for EC, < 2 for casts and < 173 for bacteria, respectively (counts per microl; 97.5 percentile). Due to the wide use of dipstick and microscopic sediment analysis in routine urine diagnostics, comparative studies on 950 random urine samples were performed. Bacterial counting combined with WBC enumeration was further compared in 266 routine urinary microbiologic cultures. RESULTS: Good correlations were found comparing UF-100 results of RBC (r = 0.89), WBC (r = 0.94), and EC (r = 0.74) with Fuchs-Rosenthal Chamber (FRC) counts. However, some misclassification of casts (r = 0.32) could be observed. Correlations of UF-100 with dipstick and sediment testing was significant (p < 0.001), but the scatter of the latter two methods is too wide to consider them as quantitative methods. Promising results further revealed that the analyzer has a good negative predictive value (NPV) for microbiologically negative cultures, especially for cultures with bacterial counts of 10(5)/l (NPV = 95%). CONCLUSION: The analyzer is capable of providing rapid and reliable urine analysis of cellular particles avoiding the known imprecision of dipstick and sediment methodology. Thus, when used in an algorithm, combined with dipstick or quantitative urine chemistry analysis (for hemoglobin, esterase, protein, glucose, etc.), this analyzer might serve as a rapid and accurate screening tool in routine urine analysis, thereby reducing manual reviewing rate as well as the number of missed samples, compared to screening with dipstick alone.  相似文献   
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