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101.
(Received for publication on Apr. 28, 1997; accepted on May 15, 1998)  相似文献   
102.
The subcutaneous pedicled V-Y advancement flap (also known as the kite flap of Dufourmentel) has been described by many authors. Its versatility in reconstructive surgery is well known, both in facial reconstructive surgery as well as surgery of the trunk and extremities. Its advantages in achieving aesthetic reconstruction in specific facial regions have been less well emphasized in the literature. The flap can be designed within natural facial creases and heals inconspicuously because of its widely based subcutaneous or muscle pedicle which incorporates venous and lymphatic drainage over most of its length. The undesirable biscuiting or flap edema frequently observed with other conventional transposition flaps is avoided. We have found the V-Y flap particularly useful in reconstructing the lower eyelid/medial canthus, supra-alar, and nasolabial regions. Our experience with over 40 such flaps is described, and technical considerations in designing and elevating the flap are discussed.  相似文献   
103.
Non-Hodgkin's lymphoma of the central nervous system (NHL-CNS) is thought to account for about 1 % of primary brain tumours. Radiation therapy has mainly been applied to treat cerebral lymphoma, but the low cure rate and the lack of enduring response have stimulated the search for alternatives. With the aim of postponing radiotherapy as long as possible, we tested the efficacy of a M-BACOD schedule administered immediately after histological diagnosis in 14 patients. After two M-BACOD courses 10 (71%) patients displayed an objective response (i.e. were apparently tumour-free when examined by CT). In 6 (60%) M-BACOD-responsive patients, radiotherapy was delayed for 5 months (without recurrences after a follow-up ranging from 9 to 18 months). Moreover, in 3 M-BACOD-responsive patients, no recurrence took place (even without radiotherapy) after a follow-up of 6–12 months. We conclude that radiation can be postponed after chemotherapy or delayed until tumor recurrence.This paper was presented at the 3rd Meeting of the European Neurological Society, Lausanne, 27 June–1 July, 1992  相似文献   
104.
Summary The effect of sodium ion on 3H-(–)-noradrenaline (0.0875 to 0.5 M) transport by rat heart atrial hemi-appendages incubated in vitro has been studied, and the following observations made: a) When sodium was omitted (choline and lithium substitution) there was no evidence for active noradrenaline transport, and only a component that did not show saturation kinetics up to 1 M noradrenaline, remained. b) Omission of sodium or addition of 4×10–5 M desipramine inhibited noradrenaline transport to exactly the same extent, and their effects were not additive. Alprenolol did not reduce this sodium-independent transport, but tropolone lowered it somewhat. c) No evidence for corticosterone-sensitive noradrenaline transport (uptake-2) was found in this preparation at the low amine concentrations used. d) In control medium, the kinetic parameters of transport were: K m: 0.59 ± 0.063 M and V max: 2.44 ± 0.43 (pmoles/mg protein/min). With 26 mM sodium and the rest substituted by choline, K m:2.26 ± 0.70 M (P0.001) and V max: 2.74 ± 0.43 (pmoles/mg protein/min) (not significant). Also with 26 mM sodium, but with sucrose substitution, K m: 0.76 ± 0.13 M (N.S.) and V max: 1.06 ± 0.13 (pmol/mg/min) (P<0.05). Such results indicate that sodium only modifies the affinity of the transport system for noradrenaline, without changing V max, and that changes in the latter are only a consequence of a reduction of the ionic strength. e) When noradrenaline transport was studied at different concentrations of external sodium, at constant ionic strength and with precautions to minimize the noradrenaline-releasing effect of low sodium, it was found that the data could be best represented by two hyperbolas placed in series. This suggests that the noradrenaline carrier has two sites for sodium, that do not interact with each other. When the same experiments were repeated in the absence of chloride, it was found that the noradrenaline transport system had lost virtually all its affinity for sodium. f) The effect of prolonged tissue incubation in the absence of sodium was found to produce a relatively small inactivation of noradrenaline transport. Such phenomenon was enhanced by raising the calcium concentration to 2 mM.  相似文献   
105.
The role of socioeconomic and anthropometric indicators, tobacco, alcohol consumption, dietary habits, and medical history in the etiology of soft-tissue sarcoma (STS) was examined in a hospital-based case-control study, conducted in the Friuli-Venezia Giulia region of northeast Italy, between 1985 and 1990. A total of 88 STS cases (53 males and 35 females; median age: 52 years) and of 610 controls (306 males and 304 females; median age: 54 years) were interviewed. There were significant excess risks associated with a history of herpes zoster infection (odds ratio [OR]=2.4,95 percent confidence interval [CI]=1.1–5.3), chicken pox (OR=2.2, CI=1.2–4.3) and mumps in childhood (OR=2.0, CI=1.1–3.9). History of diabetes was also linked to a nonsignificant increase in STS risk (OR=1.8, CI=0.6–5.4), whereas exposure to radiation for diagnostic or therapeutic purposes was not related to the probability of developing STS. None of the investigated socioeconomic and anthropometric indicators seemed to affect STS risk; neither did tobacco smoking, nor consumption of alcohol, coffee, and tea beverages. Conversely, among the dietary habits investigated, a significant positive association emerged with an increasing frequency of consumption of dairy products (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiiYdd9qrFfea0dXdf9vqai-hEir8Ve% ea0de9qq-hbrpepeea0db9q8as0-LqLs-Jirpepeea0-as0Fb9pgea% 0lrP0xe9Fve9Fve9qapdbaqaaeGacaGaaiaabeqaamaabaabcaGcba% Gaae4XdmaaCaaaleqabaGaaGOmaaaaaaa!3DA2!\[{\rm{\chi }}^2\]for trend=6.8, P<0.01) and oil (% MathType!MTEF!2!1!+-% feaafeart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqefm0B1jxALjhiov2D% aebbfv3ySLgzGueE0jxyaibaiiYdd9qrFfea0dXdf9vqai-hEir8Ve% ea0de9qq-hbrpepeea0db9q8as0-LqLs-Jirpepeea0-as0Fb9pgea% 0lrP0xe9Fve9Fve9qapdbaqaaeGacaGaaiaabeqaamaabaabcaGcba% Gaae4XdmaaCaaaleqabaGaaGOmaaaaaaa!3DA2!\[{\rm{\chi }}^2\]for trend=4.3, P<0.05), while a negative association was seen for intake of whole grain bread and pasta (OR for highest cf lowest tertile=0.4, CI=0.2–0.9).Support for this project was contributed by the Italian Association for Cancer Research, Milan, and the Italian National Research Council (CNR Applied Project Oncology, Contract 87.01544.44).  相似文献   
106.
107.
PURPOSE: Brostallicin (PNU-166196) is a alpha-bromoacrylic DNA minor groove binder, currently in clinical evaluation. This drug has the peculiarity of showing enhanced antitumor activity in cells with high glutathione S-transferase (GST)/glutathione content. The purpose of the study was to study multiple combinations of brostallicin with classical anticancer agents. EXPERIMENTAL DESIGN: The cis-dichloro-diammine-platinum (cDDP)/brostallicin combination was tested in the human colon carcinoma (HCT-116) model transplanted in nude mice. Two treatment schedules were tested: cDDP followed by brostallicin 48 h after or brostallicin followed by cDDP. These two schemes were selected from the observation that tumor cells in vitro show an increased activity of GST 48 h after cDDP treatment. The HCT-116 model was used also to test the irinotecan (cPT-11)/brostallicin combination. The effect of brostallicin in combination with doxorubicin (DX) was studied in the i.v. injected murine L1210 leukemia. Three administration schedules were tested. The antitumor activity of brostallicin and Taxotere was tested on the A549 lung cancer xenografts. RESULTS: In line with the increased GST activity observed after treatment with cDDP, the cDDP/brostallicin interaction was sequence-dependent, leading to a more than additive antitumor effect, without additional toxicity, only when cDDP was given before brostallicin. The antitumor effect of CPT-11 was enhanced significantly by brostallicin cotreatment. A more than additive antitumor effect, without additional toxicity, was observed when DX/brostallicin were sequentially administered in L1210-bearing mice. Finally, additivity was observed when brostallicin/Taxotere simultaneous combination was tested. CONCLUSIONS: Although the precise molecular mechanism of interaction between brostallicin and the other tested cytotoxics has not yet been identified, a clear therapeutic gain is observed in preclinical models when brostallicin is combined with anticancer agents such as cDDP, DX, CPT-11, and Taxotere. These results indicate the potential therapeutic value of brostallicin in cancer combination treatment therapy.  相似文献   
108.
109.
110.
In adult Sprague-Dawley rats, retinal ganglion cell survival was investigated after intraorbital optic nerve section and after transient ischemia of the retina induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The thickness of the inner nuclear and inner plexiform layers was also assessed after transient periods (120 min) of retinal ischemia induced by selective ligature of the ophthalmic vessels. In addition, we have also investigated the neuroprotective effects of different substances in these paradigms. The intraocular injection of brain-derived neurotrophic factor increased RGC survival after retinal ischemia induced by elevation of the intraocular pressure or by selective ligature of the ophthalmic vessels. The caspase-inhibitor Z-DEVD increased retinal ganglion cell survival after optic nerve section and also after 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. The peptide Bcl-2 did not increase retinal ganglion cell survival after optic nerve section but increased retinal ganglion cell survival after 60 or 90 min of retinal ischemia induced by selective ligature of the ophthalmic vessels. Finally, BDNF, nifedipine, naloxone and bcl-2 prevented in part the decrease in thickness of the inner nuclear layer and inner plexiform layer induced by selective ligature of the ophthalmic vessels. Our results suggest that retinal ganglion cell loss induced by different types of injury, may be prevented by substances with neuroprotective effects, by altering steps of the cascade of events leading to cell death.  相似文献   
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