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101.
Dorsal fusion with the internal fixator has become the standard treatment of instabilities and deformities of the thoracolumbar spine. With our new device, the modular spine fixator (MSF), which has been specially designed for short-distance instrumentations, we have increasingly been treating unstable injuries of the thoracolumbar spine by one-level stabilization. Prerequisite is an accurate evaluation of the indication, including CT and MRI to assess the involvement of the intervertebral disc and the ligamental structures. The operative technique differs in some details from the procedure in more-multi-level instrumentations, especially concerning the application of the pedicle screws. The instrumentation is always combined with posterior allogenic bone grafting. Since the beginning of 1993 we also perform anterior autogenic transpedicular bone grafting. Between January 1991 and July 1995, 57 one-level stabilizations with the MSF were performed. Of the 57 patients operated on 39, 27 men and 12 women, with an average age of 41 years, have had a clinical and radiographic follow-up examination so far, on average, 27 months after the accident. Seventeen patients were completely free of pain and 17 patients (were only) sensitive to weather changes or had minor pain during great physical stress. Five patients had pain even during slight physical stress or at rest. The preoperatively measured Cobb angle was 15.1 degrees on average, after the operation 5.2 degrees, and at the time of the follow-up examination amounted to 8.1 degrees. The patients' range of motion was normal. Only five minor complications have been seen. No implant fatigue failure has been noted in this series. We derive from these results that, for correct indications, one-level stabilization can be performed successfully and should be firmly established in the operative treatment of unstable fractures of the thoracolumbar spine.  相似文献   
102.
Corticosteroids are effective in bringing about a clinical remission in patients with ulcerative colitis. However, in severely relapsed cases, corticosteroids are not always effective even when a high dosage is administered. In addition, the long-term use of corticosteroids often causes serious side effects. Therefore, an alternative treatment for active ulcerative colitis is necessary in order to avoid these clinical problems. In the present pilot study, the efficacy of leukocytapheresis using a centrifugal procedure was evaluated for corticosteroid-resistant, active ulcerative colitis. Fourteen patients with corticosteroid-resistant severely active ulcerative colitis were treated by leukocytapheresis. Thirteen patients (92.9%) achieved clinical remission within 4 weeks after the apheresis, and remained in remission for 8 months on average without any additional corticosteroid therapy. In the remaining patient, in whom remission was not induced, a total colectomy was performed immediately after the fourth course of leukocytapheresis. No significant side effects were noticed throughout the therapy. Both colonoscopic and histological examinations confirmed the beneficial effect of this procedure in terms of the reduction of severe inflammation of the affected colon. We found that the expression of two adhesion molecules, L-selectin and VLA4a, on the surface of peripheral leukocytes was decreased after this new therapy.  相似文献   
103.
An annual atmospheric pollen survey was performed for 14 consecutive years in the autumn at Sakado city, Saitama prefecture. The survey was performed on the transition of pollen dispersion of major allergen plants: ragweed (Ambrosia spp.), Humulus japonicus, Artemisia spp. and Gramineae. 1. Annual total pollen count of ragweed showed marked increases beginning from 1991. Total pollen count in 1991 was 8.8 times and that in 1996 was 18.6 times that in 1983. This increase is probably caused by marked proliferation of giant ragweed which is left without mowing as it is on a dry riverbed, and consequently produces much more pollen than short ragweed. 2. Annual increases in total pollen counts of other major plants which disperse their pollen in the same season as ragweed were 0.95 times in 1991 and 0.5 times in 1996 that in 1983 for Humulus japonicus, 0.68 times in 1991 and 1.5 times in 1996 that in 1983 for Artemisia spp. and 1.3 times in 1991 and 1.4 times in 1996 that in 1983 for Gramineae. None of these species showed a marked increase of pollen dispersion although they showed some annual variation. The above findings suggest that changes in the proliferous state of various allergenic plants due to environmental change should be considered with respect to characteristics of pollen allergy.  相似文献   
104.
OBJECTIVE: To examine specifically the influence of estimated perioperative mortality and stroke rate on the assessment of appropriateness of carotid endarterectomy. DATA SOURCES/STUDY SETTING: An expert panel convened to rate the appropriateness of a variety of potential indications for carotid endarterectomy based on various rates of perioperative complications. We then applied these ratings to the charts of 1,160 randomly selected patients who had carotid endarterectomy in one of the 12 participating academic medical centers. STUDY DESIGN: An expert panel evaluated indications for carotid endarterectomy using the modified Delphi approach. Charts of patients who received surgery were abstracted, and clinical indications for the procedure as well as perioperative complications were recorded. To examine the impact of surgical risk assessment on the rates of appropriateness, three different definitions of risk strata for combined perioperative death or stroke were used: Definition A, low risk < 3 percent; Definition B, low risk < 5 percent; and Definition C, low risk < 7 percent. PRINCIPAL FINDINGS: Overall hospital-specific mortality ranged from 0 percent to 4.0 percent and major complications, defined as death, stroke, intracranial hemorrhage, or myocardial infarction, varied from 2.0 percent to 11.1 percent. Most patients (72 percent) had surgery for transient ischemic attack or stroke; 24 percent of patients were asymptomatic. Most patients (82 percent) had surgery on the side of a high-grade stenosis (70-99 percent). When the thresholds for operative risk were placed at the values defined by the expert panel (Definition A), only 33.5 percent of 1,160 procedures were classified as "appropriate." When the definition of low risk was shifted upward, the proportion of cases categorized as appropriate increased to 58 percent and 81.5 percent for Definitions B and C, respectively. CONCLUSIONS: Despite the high proportion of procedures performed for symptomatic patients with a high degree of ipsilateral extracranial carotid artery stenosis and generally low rates of surgical complications at the participating institutions, the overall rate of "appropriateness" using a perioperative complication rate of < 3 percent was low. However, the rate of "appropriateness" was extremely sensitive to judgments about a single clinical feature, surgical risk. These data show that before applying such "appropriateness" ratings, it is crucial to perform sensitivity analyses in order to assess the stability of the results. Results that are robust to moderate in variation in surgical risk provide a much sounder basis for policy making than those that are not.  相似文献   
105.
Renal cell carcinoma may metastasize to the head and neck region at different stages of its evolution. We present a case of an undiagnosed renal cell carcinoma presenting as an ear polyp, and discuss the difficulties of the diagnosis and the management of these tumours.  相似文献   
106.
107.
Hypercholesterolemia and mesangial cell proliferation have been proposed to play a role in the progression of glomerulosclerosis in diabetic nephropathy and other renal diseases. Although LDL is mitogenic for and cytotoxic to mesangial cells, the effect of HDL on these cells is unknown. HDL stimulates fibroblast mitogenesis and is the principal cholesterol-bearing lipoprotein in the rat, the experimental model for studying the effect of hyperlipidemia on renal disease. Insulin is mitogenic in several cell systems, and its levels are increased in serum in non-insulin-dependent diabetes mellitus. This study investigates whether HDL acts as a growth factor in mesangial cells and whether it functions in parallel with insulin. It was found that HDL at protein concentrations between 10 and 500 microg/ml, both alone and in the presence of 100 nM insulin, increased DNA synthesis in mesangial cells (129 to 165% of control for HDL alone; 140 to 235% for HDL plus insulin), whereas HDL at 1000 microg/ml and greater inhibited mesangial cell proliferation. Insulin alone at 100 nM stimulated [3H]thymidine incorporation in the same cell system (145% of control); the mitogenic effect of insulin was additive to that of HDL. Purified apo A-I had a similar effect, but at significantly lower concentrations. Specific binding of HDL to mesangial cells was demonstrated (B(max) [binding constant] of 5.19 +/- 0.70 x 10(-7) micromol of HDL bound/mg cell protein and K(b) of 2.83 +/- 0.22 nM). Tetranitromethane alters apo A-I, preventing binding to its cognate receptor. Tetranitromethane-modified HDL did not bind to mesangial cells and had no effect on [3H]thymidine incorporation. Addition of HDL to mesangial cells caused an immediate transient increase in free intracellular calcium in several representative mesangial cells, similar to the response seen with platelet-derived growth factor. The mitogenic effect of HDL was not altered after attenuation of cellular protein kinase C activity, but the stimulatory effect of HDL alone and in combination with insulin on DNA synthesis was completely eliminated after inhibition of cellular tyrosine kinases by 24-h pretreatment with 0.25 microM herbimycin A. Thus, HDL binds to a specific apo A-I-dependent receptor, promotes DNA synthesis, and initiates second-messenger events by a tyrosine kinase-dependent and protein kinase C-independent mechanism.  相似文献   
108.
We have studied mechanisms by which leptin overexpression, which reduces body weight via anorexic and thermogenic actions, induces triglyceride depletion in adipocytes and nonadipocytes. Here we show that leptin alters in pancreatic islets the mRNA of the genes encoding enzymes of free fatty acid metabolism and uncoupling protein-2 (UCP-2). In animals infused with a recombinant adenovirus containing the leptin cDNA, the levels of mRNAs encoding enzymes of mitochondrial and peroxisomal oxidation rose 2- to 3-fold, whereas mRNA encoding an enzyme of esterification declined in islets from hyperleptinemic rats. Islet UCP-2 mRNA rose 6-fold. All in vivo changes occurred in vitro in normal islets cultured with recombinant leptin, indicating direct extraneural effects. Leptin overexpression increased UCP-2 mRNA by more than 10-fold in epididymal, retroperitoneal, and subcutaneous fat tissue of normal, but not of leptin-receptor-defective obese rats. By directly regulating the expression of enzymes of free fatty acid metabolism and of UCP-2, leptin controls intracellular triglyceride content of certain nonadipocytes, as well as adipocytes.  相似文献   
109.
BACKGROUND: Increases in life stress have been linked to poor prognosis, after myocardial infarction (MI). Previous research suggested that a programme of monthly screening for psychological distress, combined with supportive and educational home nursing interventions for distressed patients, may improve post-MI survival among men. Our study assessed this approach for both men and women. We aimed to find out whether the programme would reduce 1-year cardiac mortality for women and men. METHODS: We carried out a randomised, controlled trial of 1376 post-MI patients (903 men, 473 women) assigned to the intervention programme (n = 692) or usual care (n = 684) for 1 year. All patients completed a baseline interview that included assessment of depression and anxiety. Survivors were also interviewed at 1 year. FINDINGS: The programme had no overall survival impact. Preplanned analyses showed higher cardiac (9.4 vs 5.0%, p = 0.064) and all-cause mortality (10.3 vs 5.4%, p = 0.051) among women in the intervention group. There was no evidence of either benefit or harm among men (cardiac mortality 2.4 vs 2.5%, p = 0.94; all-cause mortality 3.1 vs 3.1%, p = 0.93). The programme's impact on depression and anxiety among survivors was small. INTERPRETATION: Our results do not warrant the routine implementation of programmes that involve psychological-distress screening and home nursing intervention for patients recovering from MI. The poorer overall outcome for women, and the possible harmful impact of the intervention on women, underline the need for further research and the inclusion of adequate numbers of women in future post-MI trials.  相似文献   
110.
DJ Hackam  RA Superina  RH Pearl 《Canadian Metallurgical Quarterly》1997,32(7):1028-31; discussion 1031-2
Current management of Hirschsprung's disease (HD) typically involves staged therapy, which necessitates multiple hospital admissions and associated costs. The authors therefore investigated the course and outcome of treating such children using a single-staged (SS) approach, and compared them with those treated via multiple-staged (MS) therapy. The cases of one hundred nine consecutive patients who presented with HD from 1991 to 1996 were reviewed. Four patients were excluded (two unrelated deaths, two with small intestinal aganglionosis). Twenty-one of the remaining 105 patients underwent SS repair. Both groups were similar in gender, age at diagnosis, and frequency of comorbidities. Repair was possible in 100% of the SS patients. Complications, including enterocolitis, occurred in 63% of patients, and did not significantly differ between groups. The outcome in SS patients was unaffected by whether the repair was performed before or after 30 days of life. The outcome was unaffected by operative weight in either group. By contrast, the number of hospital admissions and total length of stay was significantly higher in the MS group, which resulted in a twofold increase in total costs associated with MS repair compared with SS repair. These data indicate that primary repair of HD is efficacious (even in the newborn), with morbidity equal to MS repair, and requires fewer hospital admissions. The significant savings to the patient and the health care system suggest that SS repair may be an improved strategy for treating HD.  相似文献   
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