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1.
The optimal extent of breast resection before irradiation for treatment of early breast cancer has not been defined. Increasing the size of the resection may decrease the risk of local recurrence but will also have an adverse impact on the cosmetic outcome. The 5-year likelihood of a recurrence of the tumor was analyzed in relation to the volume of resected breast tissue in 507 patients with infiltrating ductal carcinoma treated with conservative surgery and radiation therapy between 1968 and 1982. Patients were stratified by clinical T-stage and for each T-stage patients were divided into three groups of equal numbers based on the volume of excised tissue. All patients had at least a gross excision of the tumor and the extent of breast resection was determined at the discretion of the surgeon without knowledge of the histologic features of the tumor. The median follow-up time was 100 months. The 5-year actuarial recurrence rates were analyzed in relation to clinical T-stage (T1 or T2) and the presence or absence of an extensive intraductal component (EIC+ or EIC-). For patients with EIC+ tumors, the largest resections were associated with a substantially lower risk of recurrence in the breast than the smallest resections. This effect was seen both for T1 tumors (10% versus 29%, p = 0.07) and for T2 tumors (9% versus 36%, p = 0.04). For patients with EIC-tumors, recurrence rates were significantly lower than for EIC+ tumors and were not influenced by the volume of resection to the same degree as EIC+ tumors. In the absence of an EIC, recurrence rates for the largest and smallest resections were 0% and 9% (p = 0.02) for T1 tumors and 3% and 6% (p = NS) for T2 tumors. It is concluded that a limited breast resection is acceptable for an EIC- tumor but that a more extensive resection is required for an EIC+ tumor. These results stress the importance of assessing the presence or absence of an EIC in determining the optimal extent of breast resection required before radiation therapy.  相似文献   
2.
The amino/imino equilibrium is studied in free bases and hydrochloride salts of amidinobenzisothiazole derivatives by IR and 1H-NMR spectroscopy. The X-ray crystallographic analysis of two of these compounds shows that the free base exists as amino form whereas the hydrochloride as imino form.  相似文献   
3.
The action of kynurenic acid on currents elicited by the activation of amino acid receptors was investigated in primary cultures of cortical neurons prepared from neonatal rats. Kynurenic acid was tested on currents elicited by both N-methyl-D-aspartic acid (NMDA) and kainate, using patch-clamp recording techniques in "outside-out" and "whole-cell" configurations. The inhibition by kynurenic acid was compared with that elicited by amino-phosphono-valeric acid (APV). Whole-cell currents, elicited by increasing doses of NMDA, were antagonized competitively by APV and non-competitively by kynurenic acid (ID50 70 microM); in contrast, kynurenic acid inhibited competitively the whole-cell currents elicited by kainic acid (ID50 500 microM). The non-competitive inhibition by kynurenic acid of the whole cell currents elicited by NMDA was antagonized competitively by glycine, a specific positive allosteric modulator of NMDA receptors; on the other hand glycine failed to change the inhibition by APV of the NMDA-elicited responses. Thus, kynurenic acid inhibits NMDA receptors allosterically (non-competitively) and kainic acid receptors isosterically (competitively).  相似文献   
4.
Two cases are reported of liver angiosarcoma occurring among polyvinyl chloride (PVC) extruders from a small Italian factory producing PVC bags and other containers. The possibility that PVC extrusion carries a risk of liver angiosarcoma is important because of the very large number of people working with extruding, manufacturing and handling PVC, as compared with the number of people working in PVC polymerization and/or VC production. In the past, the level of vinyl chloride (VC) concentration in PVC extrusion workplaces has been thought to be "safe".  相似文献   
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Significant reduction of snoring noise and valid prevention of neurological and/or cardiovascular complications of OSAS are the basic goals of all modern snoring and OSAS surgical procedures. Any kind of operation, single or multiple, included into a one-step or multistep programs, is said to fail if snoring is not reduced to a significant extent for the patient or if clinical and/or instrumental data after the operation show that Upper Airways Resistance Syndrome (UARS) or OSAS continues to be probably dangerous for the patient to some extent. The real figure of failures in different situations of sleep-disordered syndromes surgery is discussed, along with the possible explanations. A group of patients operated on for snoring and OSAS in our clinic is analyzed retrospectively from the subjective point of view and by means of sleep studies to get a precise quantitative and qualitative idea of the failed cases. The final goal would be to understand how it is possible to reduce to a minimal level the number of true failures.  相似文献   
7.
The present study compares the efficacy and safety of betahistine dihydrochloride to that of a placebo in recurrent vertigo resulting from Meniere's disease (MD) or in paroxysmal positional vertigo (PPV) of probable vascular origin. The design was double-blind, multicentre and parallel-group randomised. Eleven Italian centres enrolled 144 patients: 75 of the patients were treated with betahistine (41 MD/34 PPV) and 69 with placebos (40 MD/29 PPV). The betahistine dosage was 16 mg twice per day for 3 months. Compared to the placebo, betahistine had a significant effect on the frequency, intensity and duration of vertigo attacks. Associated symptoms and the quality of life also were significantly improved by betahistine. Both the physician's judgement and the patient's opinion on the efficacy and acceptability of the treatment were in agreement as to the superiority of betahistine. The effective and safe profile of betahistine in the treatment of vertigo due to peripheral vestibular disorders was confirmed.  相似文献   
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OBJECTIVE: The authors reviewed their institution's experience treating mammographically detected ductal carcinoma in situ (DCIS) of the breast with breast-conserving therapy (BCT) to determine 10-year rates of local control and survival, patterns of failure, and factors associated with outcome. SUMMARY BACKGROUND DATA: From January 1980 to December 1993, 177 breasts in 172 patients were treated with BCT for mammographically detected DCIS of the breast at William Beaumont Hospital, Royal Oak, Michigan. METHODS: All patients underwent an excisional biopsy, and 65% were reexcised. Thirty-one breasts (18%) were treated with excision alone, whereas 146 breasts (82%) received postoperative radiation therapy (RT). All patients undergoing RT received whole-breast irradiation to a median dose of 50.0 Gy. One hundred thirty-six (93%) received a boost to the tumor bed for a median total dose of 60.4 Gy. Median follow-up was 5.9 years for the lumpectomy alone group and 7.2 years for the lumpectomy + RT group. RESULTS: In the entire population, 15 patients had an ipsilateral breast recurrence. The 5- and 10-year actuarial rates of ipsilateral breast recurrence were 7.8% and 7.8% for lumpectomy alone and 8.0% and 9.2% for lumpectomy + RT, respectively. Eleven of the 15 recurrences developed within or immediately adjacent to the lumpectomy cavity and were designated as true recurrences or marginal misses (TMM). Four recurred elsewhere in the breast. Eleven of the 15 recurrences were invasive, whereas 4 were pure DCIS. Only one patient died of disease, yielding 5- and 10-year actuarial cause-specific survival rates of 100% and 99.2%, respectively. Eleven patients were diagnosed with subsequent contralateral breast cancer, yielding 5- and 10-year actuarial rates of 5.1% and 8.3%, respectively. Clinical, pathologic, and treatment-related factors were analyzed for an association with ipsilateral breast failure or TR/MM. No factors were significantly associated with ipsilateral breast failure. In the entire population, the omission of RT and younger age at diagnosis were significantly associated with TR/MM. Patients younger than 45 years at diagnosis had a significantly higher rate of TR/MM in both the lumpectomy + RT and lumpectomy alone groups. None of the 37 patients who received a postexcisional mammogram had an ipsilateral breast failure versus 15 in the patients who did not receive a postexcisional mammogram. CONCLUSIONS: Patients diagnosed with mammographically detected DCIS of the breast appear to have excellent 100-year rates of local control and overall survival when treated with BCT. These results suggest that the use of RT reduces the risk of local recurrence and that patients diagnosed at a younger age have a higher rate of local recurrence with or without the use of postoperative RT.  相似文献   
10.
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