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111.
Dentin sensitivity (DS) is a painful clinical condition which may affect 8-35% of the population. Various treatment modalities have claimed success in relieving DS, although at present there does not appear to be a universally accepted desensitizing agent. Current opinion based on Br?nnstr?m's Hydrodynamic Theory would suggest that following exposure of the dentin surface (through attrition, abrasion, or erosion), the presence of open dentinal tubules, patent to the pulp, may be a prerequisite for DS. The concept of tubule occlusion as a method of dentin desensitization, therefore, is a logical conclusion from the hydrodynamic theory. The fact that many of the agents used clinically to desensitize dentin are also effective in reducing dentin permeability tends to support the hydrodynamic theory. This paper reviews the in vitro evaluation of desensitizing agents, the techniques used to characterize their effects on the prepared dentin surface, and the ability of these agents to reduce permeability through tubule occlusion, and presents recent findings from ongoing research based on the Pashley Dentin Disc model. It can be concluded that the use of this model to determine surface characteristics, and reductions in dentin permeability through tubule narrowing or occlusion, provides a useful screening method for evaluating potential desensitizing agents. Interpreting changes observed in vitro is difficult, and extrapolation to the clinical situation must be tempered with caution.  相似文献   
112.
Many patients diagnosed with breast cancer will develop metastases and these have diverse presentations. We have reviewed 100 consecutive patients who have died with metastatic breast cancer, to determine the frequency, sites and mode of presentation of recurrent disease. The commonest site of failure was loco-regional (n = 61), this usually presented with a mass, but a minority of patients also complained of pain. Bone metastases developed in 60 patients and produced bone pain, pathological fracture (n = 6) or cord compression (n = 5). Pulmonary metastases producing shortness of breath were diagnosed in 34 patients and were asymptomatic in a further 10. Intra-abdominal metastases were found at some time in 23 patients, most commonly in the liver (n = 20) and the majority complained of epigastric pain (n = 17). Brain metastases occurred in 23 patients and produced a wide range of symptoms including those of a space-occupying lesion (n = 10), cranial nerve palsy (n = 7), diabetes insipidus (n = 3), focal limb weakness (n = 2) and meningitis (n = 1). Three patients had choroid metastases producing reduced visual acuity. Recurrent breast carcinoma can present in a variety of ways, therefore any new symptom or sign should be considered to represent recurrence until proved otherwise.  相似文献   
113.
BACKGROUND: Recent in vitro data indicate that the oncogenic effects of activated ras genes may be mediated, at least in part, through inhibition of apoptotic cell death. To examine this proposition in vivo, the relationship between mutations of the K-ras gene and the frequency of apoptosis was studied in a series of 69 sporadic colorectal neoplasms (11 adenomas and 58 carcinomas). METHODS: Mutations in codon 12 of K-ras were determined by a single tube, enriched polymerase chain reaction. Apoptotic cells in tumor sections were identified by in situ end-labeling of fragmented DNA, whereas levels of bcl-2 and p53 proteins were determined by immunohistochemistry. RESULTS: Tumors with mutant K-ras had a significantly lower apoptotic index than those with the wild-type allele (P < 0.05). They were also more likely to exhibit positive bcl-2 staining (P < 0.05). Adenomas showed significantly greater bcl-2 positivity than carcinomas (89% and 51%, respectively; P < 0.05). The frequency of apoptosis in these tumors was not related to either bcl-2 positivity or p53 status. CONCLUSIONS: These findings suggest that activation of K-ras in colorectal carcinoma may inhibit apoptosis and thus favor tumor progression. Alternatively, this association may reflect an accumulation of K-ras mutations in cells in which normal apoptotic pathways have been impaired.  相似文献   
114.
BACKGROUND/AIMS: The aim of this study was to evaluate the combination of immunochemotherapy and stop-flow upper abdominal chemotherapy in the prolongation of survival in patients with unresectable pancreatic cancer. METHODOLOGY: Thirty unresectable pancreatic cancer patients were treated with immuno-chemotherapy in combination with stop-flow upper abdominal chemotherapy, in an attempt to improve survival time. RESULTS: The results obtained in this study indicate that this kind of treatment is feasible, safe and effective for patients suffering from Stage III and IV pancreatic duct carcinoma. Twenty per cent of the patients within this group were able to undergo radical resection and remain alive and free of disease, with a mean survival rate of 16 months. CONCLUSION: The multi-modality approach used in this study achieved promising results for pancreatic cancer patients and is recommended as a promising therapeutic alternative.  相似文献   
115.
PURPOSE: To compare standard therapy with bleomycin, etoposide, and cisplatin (BEP) to experimental therapy with etoposide, ifosfamide, and cisplatin (VIP) as primary treatment of men with advanced, disseminated germ cell tumors. PATIENTS AND METHODS: A total of 304 men with advanced disseminated germ cell tumors were randomly allocated to receive four courses of BEP or VIP. Two hundred ninety-nine patients were assessable for toxicity and 286 were assessable for response. Complete response rates, favorable response (complete remission, surgical free of disease, continuous partial remission for 2+ years), time to treatment failure, and overall survival were assessed. RESULTS: Overall complete remission rate (VIP, 37%; BEP, 31%), favorable response rate (VIP, 63%; BEP, 60%), failure-free at 2 years (VIP, 64%; BEP, 60%), and 2-year overall survival (VIP, 74%; BEP, 71%) were not significantly different between the two treatments. Grade 3 or worse toxicity, particularly hematologic and genitourinary toxicity, was significantly more common in patients who received VIP. CONCLUSION: BEP and VIP produce comparable favorable response rate and survival in patients with poor-risk germ cell tumors. The substitution of ifosfamide for bleomycin, however, was associated with significantly greater toxicity. Four courses of BEP remain the standard treatment for advanced disseminated germ cell tumors.  相似文献   
116.
OBJECTIVE: The purpose of our study was to evaluate the usefulness of diagnostic joint injections in patients with foot and ankle pain when the radiologist attempts to identify the source of pain. This study also correlated the results of injection with outcome after arthrodesis. MATERIAL AND METHODS: We retrospectively reviewed the records of 22 patients who had a foot or ankle joint injected to identify a source of pain and who later underwent arthrodesis of the painful joint. All patients had long-term foot and ankle symptoms of variable causes. Twenty-four joints were assessed: 13 subtalar, five talonavicular, four ankle, one calcaneocuboid, and one metatarsocuneiform. All patients had plain radiographs, 11 had CT studies, and five had bone scans. Contrast material was used to assess adequate positioning of the needle inside the joint before injection. All joints were injected under fluoroscopic control. Steroid was added in eight joints. After injection, patients were assessed for relief of symptoms. Patients subsequently underwent arthrodesis on the basis of the results of the injection. RESULTS: In 20 patients (22 joints), long-term follow-up showed that injections allowed us to correctly identify the source of pain and successfully guide arthrodesis. Of these 20 patients, 17 had significant pain relief after injection and fusion, whereas three patients had mild or no response. With one of these patients, we injected other joints and changed surgical plans. One of the two remaining patients had more pain relief after injection than after arthrodesis. The other patient had no relief after injection, but subsequent fusion because of persistent pain was successful. We found imaging studies to be less useful than diagnostic injections when we were attempting to identify the source of pain. CONCLUSION: Intraarticular injection of anesthetic in painful foot and ankle joints helped us confirm the source of pain in 20 of 22 patients, which in turn led to successful arthrodesis and good outcomes for these patients.  相似文献   
117.
Health care costs are continuing to spiral upward despite government and public insistence on cost containment. To meet the challenge, medical professionals and organizations are seeking opportunities for cost reduction and alternatives for delivery health care. This article discusses the tools that allow the effective delivery of care using the outpatient parenteral antimicrobial therapy (OPAT) model.  相似文献   
118.
OBJECTIVE: To evaluate the effects of leaving the parietal peritoneum open at lower segment cesarean section (LSCS) measured by postoperative pain. DESIGN: A randomized, prospective and double-blind study. SETTING: Department of Obstetrics and Gynecology, Aarhus University Hospital, Denmark. POPULATION: Forty women referred for an elective cesarean section were assigned to one of two groups: peritoneum open (n=21) or peritoneum closed (n=19). METHODS: Pain was evaluated twice a day from the first to the fifth postoperative day by Visual Analog Scales. MAIN OUTCOME MEASURES: Postoperative pain. Other outcomes include usage of analgesics, bowel function, postoperative complications, and hospital stay. RESULTS: We found no overall difference in postoperative pain. A tendency to less pain was found in the non-closure group from the third postoperative day to the fifth postoperative day. No differences were found either in the incidence of postoperative complications, or the time to return of bowel function. Concerning opiate analgesics the non-closure group had a significantly higher use in the second postoperative 24-hour period, but in the remains of the registration period it was significantly lower. For oral analgesics no difference was found in the first 24-hour period, but in the remains of the period the non-closure group had a significantly lower use. CONCLUSIONS: The VAS-scales showed no difference in postoperative pain comparing closure to non-closure of the parietal peritoneum. However, the use of analgesics is lower in the non-closure group. We suggest leaving the parietal peritoneum open when performing LSCS.  相似文献   
119.
120.
OBJECTIVE: Validation a self-administered form used by patients to record their food intake and compare the recorded data with the observed intake. DESIGN: Data were obtained from an unselected cross-sectional group of hospitalized patients. SUBJECTS: Forty-five adult men and women volunteered to participate. Five of these dropped out. METHODS: Observed intake at breakfast, lunch and dinner was obtained by recording the servings of food before they were served to the patients and subtracting weighed leftovers. At meal times the patients recorded food items eaten in fractions of amount served to the nearest 25%. SETTING: Inpatients from five different wards at Rikshospitalet, Oslo. RESULTS: There was a significant under-reporting of the number of foods served (P < 0.005) resulting in a significant underestimation of energy 231 kJ (P < 0.02). There was good agreement between the patients and the observers for the portions of most foods (Kappa 0.44-0.92, P < 0.00001). The differences in amount had little influence on the difference in total energy. The difference in number of foods correlated with the difference in energy (r = 0.68, P < 0.001) and with the difference in protein (r = 0.50, P < 0.01). Patients with an underestimation of energy above 20% had forgotten seven or more food items. CONCLUSIONS: For most patients, the self-administered form adapted to the hospital menu appears to have acceptable validity, but for some patients it was unacceptable, mainly owing to food items being omitted and not because of incorrect estimate of amounts of food.  相似文献   
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