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991.
Cerec 3     
Generally, there are more wishes than technical solutions. In this context, we regard it as one of our primary tasks to constantly respond to your demands and implement them as far as the currently achievable and economically feasible state of the art allows us to. Against this background, we are especially proud of being able to present our new Cerec devices to you following a challenging but successful development and test phase: Cerec 3, the modular CAD/CAM system which flexibly meets the demands of your practice (Fig 1) Cerec Scan, the economy model for working indirectly (Fig 2), and Cerec Link, the connection software that provides all Cerec 2 users with the advantages of the new Cerec 3 software and enables concurrent designing and milling. Cerec 3, Cerec Scan, and Cerec Link now stand next to the Cerec 2, the compact CAD/CIM unit which accompanies many of you in your daily work and makes possible tooth-conserving, biocompatible, natural-looking restorations of long-lasting ceramic materials for a wide spectrum of indications and economic efficiency. The new members of the Cerec product family show significant new developments and many specifics, enabling you to meet many of your individual demands. In addition, they provide the new platform for further developments in the coming years, which we would like to start working on with you right away in the pioneering spirit of progressive dentists.  相似文献   
992.
993.
Zervixkarzinom     
For the treatment of early-stage cervical carcinomas, laparoscopic vaginal surgical methods include laparoscopically assisted radical vaginal hysterectomy and radical vaginal trachelectomy. Laparoscopy is safe for diagnosing local tumor extent, evaluating the main prognostic factors in cervical cancer, and assessing lymph node status. The oncologic safety of both techniques has been proven in prospective studies. Their low associated morbidity and fast recovery allow a valid alternative to open radical resection, for eligible patients.  相似文献   
994.
This study was conducted to investigate the effectiveness and safety of endoluminal tubal coagulation in obliterating the tubal lumen in rabbits. Forty female rabbits were subjected to laparotomy and hysterotomy. Endoluminal tubal coagulation was induced over a length of 3 cm in the proximal, extramural fallopian tube by using a heated stainless steel cannula or a cylindrical diffusing tip emitting argon laser radiation for one to 5 minutes. Tubal patency was evaluated by observing patterns of injected methylene blue and/or breeding success rates. Postoperative recovery was uneventful in all animals. A negative methylene blue test indicated occlusion in 51 of 52 tubes (tubal occlusion rate 98.1%), and a contraception rate of 100% in all 17 uteri in which the tube had been treated. The described endoluminal tubal coagulation method proved suitable for safe and effective sterilization in rabbits and has potential as a new transcervical tubal sterilization method for humans.  相似文献   
995.
E mu-pim-1 transgenic mice are predisposed to develop lymphomas. Due to their low spontaneous tumour incidence and their increased sensitivity towards the lymphomagen ethylnitrosourea these mice may present an interesting model for short-term carcinogenicity testing. Here, we report on the further exploration of this transgenic mouse model with two additional carcinogens known to have, among others, the lymphohaematopoietic system as target, i.e. benzo[a]pyrene (B[a]P) and 12-O-tetradecanoylphorbol-13-acetate (TPA). B[a]P, given three times a week (by gavage) for 13 weeks at 4.3, 13 or 39 mg/kg body weight, resulted in a dose-related increase in lymphomas up to a 90% incidence in E(mu)-pim-1 mice during the observation period of 40 weeks. B[a]P also induced tumours of the forestomach within this observation period, though at a lower incidence and apparently equally effective in wildtype and transgenic mice. TPA, on the other hand, was unable to induce lymphomas (or tumours in any other organ) in either transgenic or wildtype animals within the observation period of 44 weeks, when applied dermally at the maximum tolerated dose of 3 microg/mouse, twice a week for 35 weeks. Molecular analysis showed that B[a]P-induced lymphomas in transgenic mice were of T-cell origin, 80% of which had elevated levels of c-myc expression. None of the lymphomas had increased N-myc expression and mutation analysis of the ras-gene family revealed a K-ras mutation in only one out of eight tumours investigated. Also, none of the lymphomas showed aberrant expression of p53 as determined by immunohistochemistry. It is concluded that the E mu-pim-1 mouse model will not be very suitable for short-term carcinogenicity testing in general: only genotoxic chemicals that have the lymphohaematopoietic system as target for carcinogenesis in wild- type mice, appear to be efficiently identified.   相似文献   
996.
The present study investigated the expression and distribution of three isoforms of nitric oxide synthase (NOS) in different anatomical regions of the human stomach and in gastric neoplastic tissues by immunohistochemistry using specific antibodies. Intracellular localization of individual isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer tissues had a marked reduction of all three NOS isoforms expression. The expression of the endothelial NOS, neuronal NOS and inducible NOS in the tumor tissue was significantly lower than in normal gastric mucosa (P = 0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the expression of inducible NOS was significantly lower than the expression of both constitutive forms of NOS (P < 0.01). There was a tendency to higher expression of both constitutive forms of NOS in earlier stages T2 of the tumor compared to advanced T4 tumor. In contrast, the expression of inducible NOS was higher than in the advanced T4 tumor than in the earlier stages T2 of the tumor. The mapping of the expression of endothelial NOS, neuronal NOS and inducible NOS in human stomach showed higher expression of NOS isoforms in the distal third than in the proximal third of the stomach (P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is greater expression of NOS in the stomach corpus and in antrum than in the proximal third of the normal human stomach mirroring the anatomical predilection of common pathological changes in this part of the human stomach. Furthermore, there was loss of the expression of individual isoenzymes in gastric neoplasms.   相似文献   
997.
5-Fluorouracil in combination with leucovorin has been shown to be active in therapeutic trials of metastatic colorectal carcinoma. In this study, we administered these drugs to 72 patients with metastatic colorectal carcinoma. Thirty-six of them without previous exposure to 5-fluorouracil were treated with weekly bolus injections of 5-fluorouracil (425 mg/m2) and leucovorin (25 mg/m2) supplemented with oral levamisole. Another 36 patients with or without prior 5-fluorouracil treatment received 5-fluorouracil 3,000 mg/m2 and leucovorin 300 mg/m2 in a 48-hour continuous infusion every two weeks. Clinical efficacy and toxicity were assessed by WHO criteria. Variables were tested for relations to response and survival by univariate and multivariate analysis. The response rate was 19.4% in weekly bolus arm and 13.9% in biweekly high-dose infusion arm (P = 0.527). Median survivals in the two arms were 18.4 months (weekly) and 21 months (biweekly) respectively (P = 0.708). Gastrointestinal side effects including nausea, vomiting, diarrhea and mucositia were the major toxicities of these regimens. By multivariate analysis, the only factor to influence response rate was the site of metastases (P = 0.009). The only factor to affect survival was performance status of the patient (P = 0.0001). We concluded that the two 5-fluorouracil based regimens are well-tolerated and shown to have a response rate comparable with previous reports of similar regimens in patients with metastatic colorectal cancer. Only liver metastases seemed to have a better response to therapy. Performance status is the most important prognostic factor in patients with metastatic colorectal cancer.   相似文献   
998.
A 28-year-old woman was admitted to our Hospital with a chief complaint of progressive gingival swelling and loosening of teeth over about a year. According to past history, she had received total thyroidectomy 2 years previously due to thyromegaly. The thyroidectomy specimen was at first interpreted as 'poorly differentiated carcinoma of the thyroid'. One year ago, she began to be aware of gingival swelling and loosening of teeth. A gum biopsy was taken and the pathologic features were similar to her 'thyroid carcinoma'. Subsequent investigations, including immunohistochemical stain, showed the gum was heavily infiltrated with histiocyte-like Langerhans' cells which were positive for S-100 protein. Ultrastructural examination of the cells under electron microscope revealed many typical intra-cytoplasmic Birbeck granules. Langerhans' cell histiocytosis was diagnosed. Langerhans' cell histiocytosis with thyroid involvement is extremely rare and may run a relatively indolent course. Even on a retrospective examination, it may easily be confused with poorly differentiated carcinoma of the thyroid. We suspect that this error may have been made on other occasions and that the occurrence of this condition may be underreported.   相似文献   
999.
1000.
Sebók B  Schneider I 《Orvosi hetilap》2000,141(3):129-132
The treatment of psoriasis vulgaris with fumaric acid esters has been controversial for more than 30 years. Recently the fumaric acid derivatives are marketed antipsoriatics in many European countries. In this paper the clinical efficacy, the side effects as well as the mode of action of these highly potent substances are summarized.  相似文献   
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