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61.
Andreas Saine Granlund Michala Skovlund S rensen Claus Lindk r Jensen Birthe H jlund Bech Michael M rk Petersen 《World journal of orthopedics》2021,12(10):760-767
BACKGROUND Schwannoma is a benign, encapsulated and slowly growing tumor originating from Schwann cells and is rarely seen in the peripheral nerve system. Typical symptoms are soreness, radiating pain and sensory loss combined with a soft tissue mass.AIM To evaluate pre-and postoperative symptoms in patients operated for schwannomas in the extremities and investigate the rate of malignant transformation.METHODS In this single center retrospective study design, all patients who had surgery for a benign schwannoma in the extremities from May 1997 to January 2018 were included. The location of the tumor in the extremities was divided into five groups; forearm, arm, shoulder, thigh and leg including foot. The locations of the tumor in the nerves were also categorized as either; proximal, distal, minor or major nerve. During the pre-and postoperative clinical evaluation, symptoms were classified as paresthesia, local pain, radiating pain, swelling, impairment of mobility/strength and asymptomatic tumors that were found incidentally(with magnetic resonance imaging). The patients were evaluated after surgery using the following categories: Asymptomatic or symptomatic patients(radiating and/or local pain) and those with complications. The follow up period was from the time of surgery until last examination of the particular physician. Multivariate logistic regression analysis was performed to identify independent prognostic factors for postoperative significant symptoms at follow-up.RESULTS We identified 858 cases from the institutional pathology register. We excluded cases with duplicate diagnoses(n = 407), pathology not including schwannomas(n = 157), lesions involving the torso, spine and neck(n = 150) leaving 144 patients for further analysis. In this group 99 patients underwent surgery and there were five complications recorded: 2 infections(treated with antibiotics) and 3 nerve palsies(2 involving the radial nerve and one involving the median nerve) that recovered spontaneously. At the end of follow-up, 1.4 mo(range 0.5-76) postoperatively, we recorded a post-operative decrease in clinical symptoms: Local pain 76%(6/25), radiating pain 97%(2/45), swelling 20%(8/10). Symptoms of paresthesia increased by 2.8%(37/36) and there was no change in motor weakness before and after surgery 1%(1/1). Multivariate analysis showed that tumors located within minor nerves had a significantly higher prevalence of postoperative symptoms compared with tumors in major nerves(odds ratio: 2.63; confidence intervals: 1.22-6.42, P = 0.029). One patient with schwannoma diagnosed by needle biopsy was diagnosed to have malignant transformation diagnosed in the surgically removed tumor. No local recurrences were reported.CONCLUSION Surgery of schwannomas can be conducted with low risk of postoperative complications, acceptable decrease in clinical symptoms and risk of malignant transformation is low. 相似文献
62.
Hereditary motor and sensory neuropathies and hereditary spastic paraplegia: a magnetic stimulation study 总被引:9,自引:0,他引:9
Central motor conduction to the small hand muscles was investigated in 59 patients with peroneal muscular atrophy and hereditary spastic paraplegia (HSP) by using transcranial magnetic brain stimulation. These comprised 20 patients with type I hereditary motor and sensory neuropathy (HMSN I), 15 with type II (HMSN II), 4 with HMSN I and 10 with HMSN II with associated pyramidal features, and 10 with the "pure" form of HSP. Central motor conduction was usually normal in HMSN I, HMSN II, and HSP. In HMSN I with pyramidal signs, central motor conduction time was greatly prolonged bilaterally. This result may reflect an associated involvement of the central motor pathways in these patients. In HMSN II with accompanying pyramidal features, 6 of the 10 patients had abnormal central motor conduction, although conduction times were only slightly prolonged, suggesting a different pathophysiological pattern. 相似文献
63.
Milne Robert W. Jensen Rikke Holm Larsen Claus Evans Allan M. Nation Roger L. 《Pharmaceutical research》1997,14(8):1014-1018
Purpose. Humans and guinea pigs metabolise morphine extensively, forming the isomers morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in relatively similar ratios. Both metabolites are formed in the liver, and their greater polarity relative to the parent aglycone may limit their permeability across hepatic membranes. This study compared the disposition of hepatically-generated M3G and M6G in perfused livers isolated from guinea pigs.
Methods. Livers were perfused at 30 ml/min in a non-recirculating manner with Krebs bicarbonate buffer containing morphine (6 to 7 M). Perfusing medium, venous perfusate and bile were collected at regular intervals and concentrations of morphine, M3G and M6G determined by reversed-phase HPLC.
Results. Concentrations of morphine, M3G and M6G in perfusate and the rates of biliary excretion of M3G and M6G were consistent between 20 and 50 min of perfusion. The mean (±s.d.) ratio for the rate of formation of M3G relative to M6G was 3.7 ± 1.5. A mean 33 ± 3% of morphine extracted by the liver was recovered as summed M3G and M6G. Of the M3G and M6G formed during a single passage, 19 ± 11% and 9 ± 9%, respectively, was excreted into bile; the values were significantly different (P = 0.002).
Conclusions. A greater fraction of hepatically-generated M3G excreted into bile compared to that for M6G reflects differences in their relative transport across sinusoidal and canalicular membranes of hepatocytes, possibly via carrier-mediated systems. 相似文献
64.
Clinical Guidelines Panel on Erectile Dysfunction: Summary Report on the Treatment of Organic Erectile Dysfunction 总被引:4,自引:0,他引:4
Drogo K. Montague James H. Barada Arnold M. Belker Laurence A. Levine Perry W. Nadig Claus G. Roehrborn Ira D. Sharlip Alan H. Bennett 《The Journal of urology》1996,156(6):2007-2011
Purpose
The American Urological Association convened the Clinical Guidelines Panel on Erectile Dysfunction to analyze the literature regarding available methods for treating organic erectile dysfunction and to make practice recommendations based on the treatment outcomes data.Materials and Methods
The panel searched the MEDLINE data base for all articles from 1979 through 1994 on treatment of organic erectile dysfunction and meta-analyzed outcomes data for oral drug therapy (yohimbine), vacuum constriction devices, vasoactive drug injection therapy, penile prosthesis implantation and venous and arterial surgery.Results
Estimated probabilities of desirable outcomes are relatively high for vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis therapy. However, patients must be aware of potential complications. The outcomes data for yohimbine clearly indicate a therapy with marginal efficacy. For venous and arterial surgery, based on reported outcomes, chances of success do not appear high enough to justify routine use of such surgery.Conclusions
For the standard patient, defined as a man with acquired organic erectile dysfunction and no evidence of hypogonadism or hyperprolactinemia, the panel recommends 3 treatment alternatives: vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis implantation. Based on the data to date, yohimbine does not appear to be effective for organic erectile dysfunction and, thus, it should not be recommended as treatment for the standard patient. Venous surgery and arterial surgery in men with arteriolosclerotic disease are considered investigational and should be performed only in a research setting with long-term followup available. 相似文献65.
Purpose
The anatomical pattern of recurrence and metastases in patients with urothelial cancer are described, and the relationship between treatment and features of the primary invasive tumor and the subsequent pattern of metastases is analyzed.Materials and Methods
Between 1976 and 1991, 240 patients with recurrent or metastatic urothelial cancer were admitted to our department.Results
The majority of the patients had recurrence within 2 years after initial diagnosis. Local recurrences and lung metastases were diagnosed significantly earlier than other metastases. Multiple sites were involved in more than half of the patients. The most common sites of recurrence were local in the bladder in 65 percent of the cases and bone in 35 percent, followed by lymph nodes in 26 percent and lung in 20 percent. The pattern of metastases was similar in patients with different histological findings, grade and location of the primary tumor. Patients younger than 60 years and those with cancer of the renal pelvis more often had distant metastases compared to older patients with bladder cancer. Local recurrences were less frequent in patients who had undergone cystectomy compared to those treated with radiotherapy only. Moreover, patients with local recurrences were likely to have metastases elsewhere.Conclusions
Bone was the most frequent site of metastases outside the pelvis and all patients suspected to have recurrence should be examined for bone metastases. The results indicate that the pattern of recurrence and metastases are not dependent on the features of the primary tumor. 相似文献66.
Hereditary neuropathy with liability to pressure palsies 总被引:1,自引:0,他引:1
Summary Clinical, neurophysiological and pathological investigations were carried out in 11 affected members of 2 families with hereditary neuropathy with liability to pressure palsies (HNPP). The observations were related to findings in 261 cases of 47 families published in the literature. It was concluded that HNPP is a nosological entity characterized by the following diagnostic criteria: (1) an autosomal dominant inheritance; (2) the clinical presentation of a recurrent mononeuropathy simplex or multiplex, frequently related to an inadequate trauma to peripheral nerves; (3) a significant slowing of motor and sensory conduction velocity in clinically affected, but also in clinically unaffected nerves; (4) characteristic morphological findings in sural nerve biopsy featuring tomaculous swellings of myelin sheaths, transnodal myelination and segmental demyelination. The pathogenesis of HNPP is not clear. Hypothetical explanations of the pathogenesis of HNPP are discussed.In memory of Albert Bischoff (1921–1981), Professor of Neurology, University of Berne 相似文献
67.
68.
Claus R?del Gerhard G Grabenbauer Thomas Papadopoulos Werner Hohenberger Hans-Joachim Schmoll Rolf Sauer 《Journal of clinical oncology》2003,21(16):3098-3104
PURPOSE: The purpose of this study was to establish the feasibility and efficacy of preoperative radiotherapy (RT) with concurrent capecitabine and oxaliplatin (XELOX-RT) in patients with rectal cancer. PATIENTS AND METHODS: Thirty-two patients with locally advanced (T3/T4) or low-lying rectal cancer received preoperative RT (total dose, 50.4 Gy). Capecitabine was administered concurrently at 825 mg/m2 bid on days 1 to 14 and 22 to 35, with oxaliplatin starting at 50 mg/m2 on days 1, 8, 22, and 29 with planned escalation steps of 10 mg/m2. End points of the phase II study included downstaging, histopathologic tumor regression, resectability of T4 disease, and sphincter preservation in patients with low-lying tumors. RESULTS: Dose-limiting grade 3 gastrointestinal toxicity was observed in two of six patients treated with 60 mg/m2 of oxaliplatin. Thus, 50 mg/m2 was the recommended dose for the phase II study. Toxicities observed at this dose level were generally mild, with only two cases of short-lived grade 3 diarrhea. Myelosuppression, mainly leukopenia, was restricted to grade 2 in 19% of patients. T-category downstaging was achieved in 17 (55%) of 31 operated patients, and 68% of patients had negative lymph nodes. Pathologic complete response was found in 19% of the resected specimens. Radical surgery with free margins could be performed in 79% of patients with T4 disease, and 36% of patients with tumors < or = 2 cm from the dentate line had sphincter-saving surgery. CONCLUSION: Preoperative XELOX-RT is a feasible and well tolerated treatment. This regimen is proposed for phase III evaluation comparing standard fluorouracil-based therapy with XELOX chemoradiotherapy. 相似文献
69.
Purposes: The study evaluates prognostic factors for dissemination and survival in patients with local or regional recurrence of breast cancer. Furthermore, the aim was to define subgroups of patients at different risk of developing metastases in specific anatomical sites. Patients and methods: The study included 140 patients with isolated local or regional node recurrence, who entered a prospective study for staging of patients with first recurrence of breast cancer in the period 1983–85. The primary treatment was a simple mastectomy; node positive patients received adjuvant radiotherapy and chemotherapy or tamoxifen.If possible, the locoregional recurrence was treated with surgery and/or radiotherapy, otherwise by systemic therapy. Results: Median follow up was 10.4 years; 78 patients developed distant metastases (soft tissue, 32%; bone, 45%; viscera 40%). Median time to dissemination was 4.4 years, and the ten year dissemination rate was 72%. Median time to dissemination was 3.7 years for patients with recurrence in the regional nodes compared to 6.5 years for patients with chest wall recurrence only, p = 0.05. No specific time sequence (temporal pattern) was observed in the anatomical distribution of metastases, and the anatomical site of recurrence could not be predicted by any of the prognostic factors. At follow up, 93 patients had died. The median survival was 5.6 years and 30% were alive after 10 years. Forty-three of the 99 patients who received local therapy only did not develop metastases. Fifteen of these patients died without evidence of metastatic disease while 28 patients were still alive without distant recurrence after a median follow up time of 9.3 years (range, 6.5–11.9 years). Level of LDH and the number of positive regional nodes (NPOS) at primary diagnosis were significant independent prognostic factors for survival after recurrence. Conclusions: Approximately one third of the patients receiving local treatment only, were alive and without distant metastases up to ten years after locoregional recurrence, indicating that there is a subset of patients which may be long term survivors after local treatment only (surgery or radiotherapy). The duration of survival can be estimated by LDH and NPOS, but the model needs validation in a separate data set before clinical use. 相似文献
70.
Cost containment has captured the attention of health policymakers in most OECD countries, and deliberations about creating powerful financial incentives dominate health care politics. Some European health systems are now implementing hospital payment schemes that mirror the U.S. model of diagnosis-related groups (DRGs) and are raising premiums and copayment levels in an effort to limit public expenditures. Though financial incentives may indeed help rein in health expenditures, focusing predominantly on financial incentives hinders due consideration of needed structural reforms that improve the continuity, quality, and appropriateness of health care service delivery. This article focuses on the structural specifics of two legally enacted health insurance systems (Germany and Austria) and two national health systems (Great Britain and Denmark) to discuss the influence of structural characteristics on cost-containment efforts. Structural reform strategies discussed include increasing reliance on general practitioners, improving coordination of community and hospital-based specialty care, addressing the stark divide between ambulatory and hospital-based care that exists in some European health systems, and improving continuity of care by better integrating medical and social care sectors. Also discussed is the relative focus on financial incentives versus structural deficits in recent European-health care reform strategies. 相似文献