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71.
Quality of complication reporting in the surgical literature   总被引:14,自引:0,他引:14  
OBJECTIVE: To identify 10 critical elements of accurate and comprehensive reports of surgical complications. SUMMARY BACKGROUND DATA: Despite a venerable tradition of weekly morbidity and mortality conferences, inconsistent complication reporting is common in the surgical literature. METHODS: An analysis of articles reporting short-term outcomes after pancreatectomy, esophagectomy, and hepatectomy was performed. Randomized clinical trials (RCTs) published from 1975 to 2001 and retrospective series of more than 100 patients published from 1990 to 2001 were reviewed. RESULTS: A total of 119 articles reporting outcomes in 22,530 patients were analyzed. This included 42 RCTs and 77 retrospective series. Of the 10 criteria developed, no articles met all criteria; 2% met 9 criteria, 38% 7 or 8, 34% 5 or 6, 40% 3 or 4, and 12% 1 or 2. Outpatient information (22% of articles), definitions of complications provided (34% of articles), severity grade used (20% of articles), and risk factors included in analysis (29% of articles) were the most commonly unmet quality reporting criteria. Type of study (RCT vs. retrospective), site of institution (U.S. vs. non-U.S.) and journal (U.S. vs. non-U.S.) did not influence the quality of complication reporting. CONCLUSIONS: Short-term surgical outcomes are routinely included in the data reported in the surgical literature. This is often used to show improvements over time or to assess the impact of therapeutic changes on patient outcome. The inconsistency of reporting and the lack of accepted principles of accrual, display, and analysis of complication data argue strongly for the creation and generalized use of standards for reporting this information.  相似文献   
72.
Early experiments indicated that islet beta-cells substantially metabolized L-alanine but that insulin secretion was largely unaffected by the amino acid. It was subsequently demonstrated using more intricate studies that L-alanine is a strong stimulus to insulin secretion in the presence of glucose in normal rodent islets and beta-cell lines. Using (13)C nuclear magnetic resonance (NMR), we have demonstrated substantial oxidative metabolism of L-alanine by the clonal beta-cell line BRIN-BD11, with time-dependent increases in production of cellular glutamate and aspartate. Stimulatory effects of L-alanine on insulin secretion were attenuated by the inhibition of beta-cell oxidative phosphorylation using oligomycin. Additionally, we detected substantial production of lactate, alanine, and glutamate from glucose (16.7 mmol/l) after 60 min. On addition of 10 mmol/l L-alanine to a stimulus of 16.7 mmol/l glucose, the utilization rate of glucose increased approximately 2.4-fold. L-Alanine dramatically enhanced NMR-measurable aspects of glucose metabolism (both oxidative and nonoxidative). The enhanced rate of entry of glucose-derived pyruvate into the tricarboxylic acid (TCA) cycle in the presence of alanine may have stimulated rates of generation of key metabolites, including ATP, which affect the insulin secretory process. Thus L-alanine metabolism, in addition to the enhancing effect on glucose metabolism, contributes to the stimulatory effects of this amino acid on insulin secretion in vitro.  相似文献   
73.
OBJECTIVE: Our purpose was to evaluate the use of whole-body MR imaging in the assessment of the extent and distribution of muscle inflammation in patients with polymyositis. CONCLUSION: Whole-body turbo short tau inversion recovery imaging is a convenient complete method of evaluating patients with muscle inflammation caused by polymyositis. This imaging technique allows us to evaluate the total inflammatory burden by revealing multiple muscle groups not seen with standard protocols.  相似文献   
74.
High-throughput genotyping technology of multiple genes based on large samples of cases and controls are likely to be important in identifying common genes which have a moderate effect on the development of specific diseases. We present here a comprehensive list of 313 known experimentally confirmed polymorphisms in 54 genes which are particularly relevant for metabolism of drugs, alcohol, tobacco, and other potential carcinogens. We have compiled a catalog with a standardized format that summarizes the genetic and biochemical properties of the selected polymorphisms. We have also confirmed or redesigned experimental conditions for simplex or multiplex PCR amplification of a subset of 168 SNPs of particular interest, which will provide the basis for the design of assays compatible with high-throughput genotyping.  相似文献   
75.
We investigated the molecular basis of hypofibrinogenemia in a woman with a plasma fibrinogen of 1.0 mg/mL. After sequencing the coding region and intronic boundaries of all three fibrinogen genes a single heterozygous GAC-->TAC mutation was identified at codon 316 of the Bbeta gene. This Asp-->Tyr substitution segregated with the hypofibrinogenemia in the only other affected family member. Examination by SDS-PAGE, isoelectric focussing, reverse phase chromatography and electrospray ionisation (ESI) mass spectrometery, failed to detect expression of the new Bbeta chain in purified plasma fibrinogen. The absence of the variant chain was confirmed by ESI tryptic mapping; while the [M + 1 H] and [M + 2 H] ions of the affected peptide (MGPTELLIEMEDWK) were clearly visible at 1,692 and 847 m/z, there were no new signals (1,741 or 871 m/z) that would at indicate expression of the variant in plasma. Asp 316 and its gamma chain homologue (Asp 252) are conserved in all known species and this is the first report of a mutation at either of these. The residue appears to be critical in maintaining the structure of the five stranded sheet that forms the dominant structural feature of the D domains.  相似文献   
76.
Chen JC  Giannotta SL  Yu C  Petrovich Z  Levy ML  Apuzzo ML 《Neurosurgery》2001,48(5):1022-30; discussion 1030-2
OBJECTIVE: Radiosurgery has emerged as an alternative treatment modality for cranial base tumors in patients deemed not suited for primary surgical extirpation, patients with recurrent or residual tumor after open surgery, or patients who refuse surgical treatment. We review our short-term experience with radiosurgical management of cavernous sinus region tumors with the Leksell gamma knife. METHODS: From August 1994 to February 1999, 69 patients with cavernous sinus lesions were treated in 72 separate treatment sessions. The tumor type distribution was 29 pituitary adenomas, 35 meningiomas, 4 schwannomas, and 1 paraganglioma. The median follow-up was 122 weeks. Lesions were stratified according to a five-level surgical grade. The grade distribution of the tumors was as follows: Grade I, 13; Grade II, 21; Grade III, 19; Grade IV, 12; Grade V, 4. Median tumor volume was 4.7 cm3. The median radiation dose was 15 Gy to the 50% isodose line. Median maximal radiation dose was 30 Gy. RESULTS: Analysis of tumor characteristics and radiation dose to optic nerve and pontine structures revealed a significant correlation between distance and dose. Much lower correlation coefficients were found between tumor volume and dose. One lesion in this series had evidence of transient progression and later regression on follow-up radiographic studies. No other lesions in this series were demonstrated to have exhibited progression. Complications after radiosurgical treatment were uncommon. Two patients had cranial nerve deficits after treatment. One patient with a surgical Grade III pituitary adenoma had VIth cranial nerve palsy 25 months after radiosurgical treatment that spontaneously resolved 10 months later. A patient with a bilateral pituitary adenoma experienced bilateral VIth cranial nerve palsy 3 months after treatment that had not resolved at 35 months after treatment. Six patients with preoperative cranial nerve deficits experienced resolution or improvement of their deficits after treatment. One patient with a prolactin-secreting adenoma experienced normalization of endocrine function with return of menses. CONCLUSION: Radiosurgical treatment represents an important advance in the management of cavernous sinus tumors, with low risk of neurological deficit in comparison with open surgical treatment, even in patients with high surgical grades.  相似文献   
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79.
BACKGROUND: Sott tissue sarcomas (STS) of the groin may present a difficult problem because or misdiagnosis as groin hernia and proximity to major neurovascular structures. We evaluated our management and survival in a large cohort of patients. STUDY DESIGN: Patients treated between July 1, 1982 and July 1, 1998 with primary or recurrent STS of the groin were included. Groin sarcomas were defined as those tumors within 5 cm of the inguinal crease. Patient, tumor, clinical, and survival data were analyzed using a log rank test and Cox regression. RESULTS: We treated and followed 88 patients with STS of the groin. The median age was 52 years (range 16 to 86 years) and 55 patients (63%) were male. Disease-specific survival was 72% at 5 years. Tumors tended to be larger than 5 cm (52%), deep (72%), and high-grade (60%). Unfavorable prognostic factors for disease-specific survival were high grade (p < 0.001), neurovascular invasion (p < 0.001), positive margin (p < 0.01), deep depth (p < 0.01), and selection for adjuvant therapy (p < 0.005). Multivariate analysis indicated age greater than 50 years (p < 0.05), high grade (p < 0.001), neurovascular invasion (p < 0.001), and positive microscopic margins (p < 0.001). Fourteen patients (16%) were diagnosed with STS at hernia operation then went on to a definitive operation with no impact on survival. Seventeen patients (19%) had involvement of a major vessel or nerve, and 5 of these ultimately required amputations, 3 for local recurrence. CONCLUSIONS: High grade, neurovascular invasion, and positive microscopic margins are associated with poor outcomes. The biology of these tumors is similar to other extremity STS, and similar principles of management apply. Even with neurovascular involvement, most patients with primary groin STS do not require amputation.  相似文献   
80.
The intraoperative use of an endoscope to localize an anteriorly based spinal pial arteriovenous fistula with minimal cord retraction and vessel manipulation is described.  相似文献   
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