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81.
82.
The classical concept of the autonomic innervation of the nasal mucosa states that the postganglionic sympathetic neurones lie in the superior cervical ganglion and those of the postganglionic parasympathetic neurones are in the pterygopalatine ganglion. We have carried out a study of the fine structure of the respiratory nasal mucosa in man and in the cat using the techniques described by Jabonero, Champy Maillet and Koelle-Friedenwald. The most striking finding was the presence of microganglia deep within the mucosa of the inferior turbinate close to the glands. These microganglia were cholinergic in nature since they demonstrated a positive reaction to anticholinesterase. From this we deduce that the nasal parasympathetic pathway has its postganglionic neurones not only in the pterygopalatine ganglion but also in these microganglia of the inferior turbinate. Each of four groups of cats were submitted to different techniques, including administration of neostigmine, inferior turbinectomy and Vidian neurectomy. Resection of the microganglia by means of turbinectomy reduced the hypersecretion caused by neostigmine and this was most noticeable when a Vidian neurectomy was carried out in addition.  相似文献   
83.
This article presents a 3-year prospective study that includes 103 consecutive patients (137 hips) diagnosed with developmental dysplasia of the hip (DDH) at birth. Treatment was started after 2 weeks only if the hips had not stabilized spontaneously. Sonographic studies were first used when clinical stability was confirmed to ensure a true concentric hip reduction. The authors conclude that most patients with DDH at birth (73.8%) do not need treatment at that time, presenting with normal hips at the end of follow-up. When instability was still present after 2 weeks and a splint was applied (26.2%), there were no significant hip differences when compared with a control group of 50 patients (69 hips) who underwent treatment in the first days of life. With this approach, the authors could safely reduce the number of patients to be treated, the amount of sonographic studies, and consequently the final cost of the whole treatment.  相似文献   
84.
. The exogenously stimulated formation of intracellularly generated protoporphyrin IX, a precursor of haem, is becoming one of the fastest developing areas in the field of photodynamic therapy (PDT). We tested the action of several free radical scavengers, amino acids, antioxidants and sulphur-containing compounds as protectors from photodamage induced by 5-aminolaevulinic acid (ALA)-mediated PDT, employing the LM2 cell line, derived from a mammary murine adenocarcinoma. We exposed the cells to different concentrations of the compounds, 24 h before PDT, during PDT, and 19 h after treatment. We defined the protection grade (PG) as the ratio between cell survival after ALA-PDT treatment in the presence of the protector and cell survival of ALA-PDT treatment alone. We found thatl -tryptophan (PG=9.2 at 2 mm ), reduced glutathione (GSH) (PG=5.8 at 0.8 mm ), N-acetyl-l -cysteine (PG=4.86 at 30 mm ), melatonin (PG=4.5 at 8 mm ) andl -methionine (PG=4.0 at 0.8 mm ) are the best protectors from PDT damage, followed byl -cysteine (PG=2.8 at 0.8 mm ), mannitol (PG=2.6 at 20 mm ) and glycine (PG=2.4 at 40 mm ) whereas oxidised glutathione and S-adenosyl-l -methionine do not exert any protection. We did not found any photoactive action of the protectors in absence of ALA. These results can be considered to modulate the photodamage induced by ALA-PDT. Paper received 24 October 2001; accepted after revision 5 May 2002. Correspondence to: Professor A. Batlle, Viamonte 1881 10A, 1056 Buenos Aires, Argentina. Fax: 54 11 4811 7447; e-mail: batlle@mail.retina.ar  相似文献   
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Avulsions and intrusions are the most complicated and controversial displacement injuries of permanent teeth. Clinical guidelines published by authorities such as the American Association of Endodontists, the Royal College of Surgeons of England and the International Association of Dental Traumatology are inconsistent. While a certain amount of inconsistency might be expected, some of these guidelines recommend treatments that are experimental or have not incorporated research information from the past 5 years, and in one case the guidelines incorrectly describe the nature of Hank's balanced salt solution. Recent laboratory studies support previous clinical outcome studies in emphasizing that only for teeth replanted within 5 minutes of avulsion is there a chance of regeneration of the periodontal ligament and normal function. Teeth replanted beyond 5 minutes will take another path, that of repair followed by root resorption, ankylosis and eventual extraction. Dentists should explain these outcomes at the time of the replantation decision. Severe intrusions also have predictable outcomes. Teeth intruded beyond 6 mm cannot regenerate a functional periodontal ligament and so are prone to root resorption and eventual extraction as well. In this situation the decision is one of immediate extraction or repositioning, with the understanding that it is inevitable that the tooth will eventually be extracted. Authoritative clinical guidelines available on the Internet provide the clinician with useful outlines for treatment. However, individual inconsistencies stimulate academic controversies and, in some cases, clinical misdirection.  相似文献   
87.
A new method of automated sleep-wake staging in the rat is described. Hippocampal electroencephalographic (HPC) and nuchal electromyographic signals were recorded by a digital polygraph. The HPC channel was filtered off-line to obtain the original plus theta and delta waves. Statistics of each of these four channels were obtained every 5 s and exported to a standard spreadsheet. The automated staging consisted of five steps: (1) automatic detection of waking, nonrapid eye movement sleep and rapid eye movement sleep patterns (5-s periods); (2) calculation of statistics for each vigilance state; (3) final classification of 5-s periods; (4) construction of a primary 20-s epoch hypnogram; and (5) automatic refinement of the previous hypnogram. The system includes indices about the accuracy of the staging and was validated with five recordings of 23 h each. The global agreement between human and automatic scoring in the validation recordings was 94.32%.  相似文献   
88.
89.
Purpose To evaluate the cosmetic outcome of breast conservative therapy and to examine the degree of agreement between the patients’ and oncologists’ ratings. We also analyze the influence of several factors on cosmesis. Methods and materials We retrospectively evaluated 145 patients with primary breast cancer treated by local excision and radiotherapy between January 2000 and May 2001. Cosmetic outcome was evaluated by doctors and patients and was scored as excellent, good, fair or poor. Results 73% of patients rated cosmesis as excellent or good while the percentage was 71% when rated by radiation oncologists. The degree of cosmesis concordance evaluated by oncologists and patients was low (kappa=0.3). In our study the variables which significantly influence on the cosmetic outcome were concomitant adjuvant chemotherapy (p=0.04) and radiation therapy boost, either by electron beam or brachytherapy (p=0.013). Conclusion The cosmetic outcome of breast conserving therapy was good. There was a similar rating by the patient and radiation oncologist, but the level of concordance between patients and doctors was low. Factors that significantly influence the cosmesis appear to be concomitant adjuvant chemotherapy and radiation therapy boost.  相似文献   
90.
Introduction Prostate volume involves a defined toxicity predictor in the radiation therapy of localized prostate cancer. Neoadjuvant hormone therapy (nHT) can reduce prostate volume and, therefore, the planned volume. The objective of this study was to establish if the value of nHT reduces the planned volume and if this reduction correlates with a reduction of the dose received in the target organs. Material and methods 28 patients diagnosed of localized prostate cancer and referred to our departments for radiation therapy with radical intention, in the period ranging between April 2002 and October 2003, were included prospectively. The patients received nHT (triptorelin+flutamide) for 2 months and adjuvant HT until completing 2 years in the high-risk cases. A transrectal ultrasound study was performed in all patients, simulation CT and planning before the start of HT and after 2 months of treatment. The radiation therapy was carried out with 6 or 18 MV LINAC photons, with a dose fractioning scheme of 5×180–200 cGy, a total dosage of 66–72 Gy to prostate, 56 Gy to seminal vesicles and, in the high-risk cases, 46 Gy to pelvic lymph nodes. Results The distribution according to risk group was: low risk 3.6%, intermediate risk 28.6% and high risk 67.9%. By transrectal ultrasound, prostate volume on diagnosis was 50.65 cc pre HT and 38.97 cc post HT (p<0.001), which means a volume reduction of 24%. The comparative analysis of the dose-volume histograms of the first versus the second CT shows a reduction in the planned volume GTV1 (prostate) (81.33 cc vs 63.96 cc, p<0.05), PTV1 (prostate and margin) (197.51 cc vs 168.38 cc, p<0.001) and PTV2 (prostate, vesicles and margin) (340.5 cc vs 307.26 cc, p<0.05), a reduction of the maximum dose in the seminal vesicles (70.2 versus 68.75 Gy, p<0.05), a reduction of the mean dose in the seminal vesicles (65.07 Gy versus 63.07 Gy, p<0.05), PTV2 (67.72 Gy versus 66.9 Gy, p<0.01) and PTV3 (prostate, vesicles, pelvic lymph nodes and margin) (58.86 Gy versus 57.21 Gy, p<0.01), a reduction of the D90 in the seminal vesicles (61.83 Gy versus 60.06 Gy, p<0.05) and PTV2 (61.04 Gy versus 59.45 Gy, p<0.05) and a reduction of V60 of the rectum (32.45% versus 28.22%, p<0.05) and V60 of the bladder (41.78% versus 31.67%, p<0.005). Conclusions Neoadjuvant hormone therapy reduces significantly prostate volume and as a result the planned volume and consequently the rectal and bladder V60 can be significantly reduced.  相似文献   
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