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91.
Adenoid cystic carcinoma: factors influencing survival.   总被引:10,自引:0,他引:10  
We have reviewed our experience with 264 patients treated for adenoid cystic carcinoma of salivary origin. This study updates a previous report from our hospital and includes all patients treated during a 30 year period who were eligible for a minimum follow-up of 10 years. The tumor arose in minor salivary (mucous) glands in two thirds of the patients; half had received treatment elsewhere, and both sexes were equally represented. Actuarial survival curves and "cure" rates calculated by the direct method confirm that clinical staging provides a reliable prognostic guide. We are unable to demonstrate that the microscopic appearance of the tumor exerts a predictable effect on treatment results. Although some patients lived for many years after resection despite local recurrence and distant metastases, prolonged survival was unusual in patients with stage 3 lesions, particularly in those with sinus or submaxillary gland primaries. Based on the site of origin of the tumor and its clinical stage, it is now possible to select which patients with adenoid cystic carcinoma have the most ominous prognosis and perhaps plan a more appropriate operation. More importantly, these data may help focus on the subpopulation at greatest risk, which is vital to the design of any prospective study to assess the value of adjunctive irradiation and chemotherapy.  相似文献   
92.
The Task Force for Creating a Biomedical Communications System for Dermatology was commissioned by the American Academy of Dermatology to develop an experimental segment of a computerized data bank on dermatologic therapy. The Task Force has completed such a "first generation" system and has named it DermRx. Its data bank carries the following information on each entry: the name of the disease; topical, systemic, physical, and other kinds of treatment; caveats; references to the literature; and the date and reviewer(s). The DermLit and DermRx programs are two components of a projected broader concept of an eventual comprehensive Biomedical Communications System for Dermatology. Such a system is envisaged as a means of making available to dermatologists diverse data relevant to practice, teaching, research, and business aspects of the specialty. At the moment, access to the stored information on dermatologic literature and therapy is by telephone call to, or by correspondence with, the central computer facility at Northwestern University. Eventually it is projected to be accessible by dedicated microcomputers housed in the physician's office. This preliminary report on DermRx is presented to review the progress of the project to date and to elicit comment upon its structure and value.  相似文献   
93.
Vascular access through subcutaneous prosthetic arteriovenous fistulas was studied in eighteen dogs. Dacron velour and woven Dacron grafts (6 mm diameter) were constructed across the lower abdomen between the common femoral artery and the opposite common femoral vein. In heparinized animals 197 percutaneous punctures were made with a "14 guage hemodialysis cannula at weekly intervals. Over a period of one and a half years there was no instance of infection. One of the fourteen Dacron velous and all four woven Dacron fistulas thrombosed. These data suggested the feasibility of achieving repetitive blood access through Dacron velour vascular prostheses. Nineteen Dacron velour fistula bypasses between the brachial artery and median basilic vein were performed in fifteen selected patients for a total dialysis period of ninety-six months. Failed standard subcutaneous fistulas or absence of suitable vessels in the upper extremity were indications for the primary procedure. Of three looped forearm fistulas, two thrombosed at twenty-two and two months. Complications among sixteen straight bypasses in the arm included two graft infections and one cannula tract infection. There were no instances of thrombosis in this group. The advantages of single needle dialysis in these high risk patients have been emphasized. Eleven grafts are presently functioning two to nine months postoperatively. Our preliminary results suggest that a Dacron velour fistula merits consideration as an alternative for vascular access in maintenance hemodialysis.  相似文献   
94.
The Authors compare the results obtained between two groups of patients suffering from leg lipodystrophy, who were subjected to a reducing lipoplasty. In the first group, surgeons made use of a new sort of cannula, deprived of the classical grip, whereas in the second group, they employed the traditional probe. The best results, achieved with the first group, prove this new operating system is really effective, particularly on legs, for the following reasons: (1) Higher precision and better control of the instrument (2) Swan-neck cannula abolition (3) Opportunity to operate with both hands (4) Halved operating time (5) No tiredness after the operation.  相似文献   
95.
Brevetoxin B1 (BTX-B1) was isolated from Austrovenus stutchburyi following the 1992-1993 outbreak of neurotoxic shellfish poisoning (NSP) in New Zealand. We report here the first isolation of PbTx-3 from the same shellfish and the development of a procedure for quantitative determination of PbTx-3 and BTX-B1. PbTx-3 was isolated by chromatography on columns of SiO2, ODS, and LH-20, followed by reverse-phase HPLCs. In mass spectrometry (MS) with an electrospray ionization (ESI) interface operating in the positive or negative ion mode, the abundant protonated ion [M+H]+ of PbTx-3 (m/z 897) and the de-sodiated ion [M-Na]- of BTX-B1 (m/z 1016) were generated, respectively. These served as precursor ions for collision-induced dissociation, and the product ions of m/z 725 from PbTx-3 and m/z 80 from BTX-B1 were identified, allowing unambiguous confirmation of these toxins by selected reaction monitoring liquid chromatography-tandem mass spectrometry (SRM LC-MS/MS) analysis. The determination limits were 0.4 and 2 ng/g for BTX-B1 and PbTx-3 at a signal-to-noise ratio of five, respectively. This LC-MS/MS method was successfully applied to determine BTX-B1 and PbTx-3 in the NSP-associated toxic shellfish. BTX-B1 was found in both A. stutchburyi and Perna canaliculus, but not in Crassostrea gigas, while PbTx-3 was found in all three.  相似文献   
96.
OBJECTIVETo promote and develop the Quality Control of Traditional Chinese Medicines (TCM). METHODTo compare the number and methods of quality control in the Chinese pharmacopoeias (I) published in different periods. To analyze the controlling level, d  相似文献   
97.
中药新药一般毒理试验及评价   总被引:4,自引:0,他引:4  
黄芝瑛 《药品评价》2004,1(1):50-52
根据多年研究实践,针对新药一般毒理试验及临床前安全性评价进行探讨,提出新药一般毒理试验需在12个环节中予以重视和加强管理。  相似文献   
98.
新辅助化疗结合保肢手术治疗肢体骨肉瘤   总被引:1,自引:0,他引:1  
陈飚  赵春和  王全 《中国肿瘤临床》2005,32(20):1162-1164,1170
目的:评价新辅助化疗结合保肢手术治疗肢体骨肉瘤的临床疗效。方法:选择1995年1月-2003年1月新辅助化疗结合保肢手术治疗的肢体骨肉瘤31例。广泛切除22例,边缘切除9例。所有病例切除标本均做多病理切片的坏死率评估结果:随访2~8年,31例中无瘤生存超过5年19例(61.3%),肿瘤局部复发4例(12.9%)。肢体功能评估优良率为67.7%:结论:新辅助化疗结合保肢手术是治疗肢体骨肉瘤理想的治疗方法,术前有效化疗是保肢术成功的关键。  相似文献   
99.
Beran RG  Beran ME 《Epilepsia》2000,41(7):875-879
PURPOSE: Trials of antiepileptic medications are usually based in tertiary referral centers with teaching hospital resources. Epilepsy Research & Services (ERS) is part of a private outpatient neurological clinic that is involved in research as part of multicenter clinical trials, adhering to Good Clinical Research Practice. ERS is subject to external monitoring and auditing, but does so outside of the teaching hospital environment. METHODS: The clinic is operated by a neurologist supported by a research assistant, administrative and nursing staff and has no formal university attachment. Patients are recruited for trials from routine referrals for clinical care. The center has formal ties with the ethics committee of the local teaching hospital, but none of the team is formally attached to that hospital. RESULTS: The center conducted trials of zonisamide, oxcarbazepine, gabapentin, remacemide, tiagabine, vigabatrin, felbamate, and lamotrigine both as add-on trials in refractory seizure disorders and as monotherapy trials in de novo epilepsy. More than 200 patients have been recruited for trials at ERS (with some patients being involved in more than one trial). External review endorsed ERS as a superior environment for such research and as a model for other centers. CONCLUSIONS: Private practice is a viable alternative for the conduct of clincial trials and should be considered when establishing such protocols. Simplicity of administration and clinical practice, which more closely mirrors standard patient care, may enhance recruitment and management.  相似文献   
100.
目的了解“七五”、“八五”、“九五”期间湖南省职业病发病状况,为湖南省“十五”期间控制职业危害提供科学依据。方法追溯15年来上报的各类资料,进行整理分析,计算出监测率、合格率、体检率、检出率、患病率。结果“七五”、“八五”、“九五”期间,湖南省共发生职业病新病例22 196例,其中尘肺占60.25%、慢性职业中毒占16.02%、急性职业中毒占8.0%、物理因素等其他职业病占13.89%;至2000年统计年止,尘肺累计病例45 956例,现患尘肺35 610例,尘肺患病率6.21%。劳动卫生监测率明显下降,合格率呈上升趋势,但职业性体检率呈下降趋势,检出率略微下降。结论湖南省职业危害状况不容忽视,防治的重点是煤炭、冶金、化工、有色金属、建材、乡镇企业等工业部门。  相似文献   
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