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101.
Heritable somatic methylation and inactivation of MSH2 in families with Lynch syndrome due to deletion of the 3' exons of TACSTD1
Ligtenberg et al. (2009)
Nature Genetics 41: 112–117  相似文献   
102.
2002年5月1日颁布实施的《中华人民共和国职业病防治法》是规范职业卫生技术服务行为的法律依据。这是职业卫生技术服务工作走上规范化、标准化、法制化的根本保障,是职业卫生技术服务机构参与市场竞争、提高服务质量、促进自身发展的必由之路,也是企业自主选择职业卫生技术服务机构、提高职业危害防治水平、促进经济发展的关键所在。4年多来,我市各级各类职业卫生技术服务机构的发展极不平衡,仪器设备配备水平、人员能力素质与我省同类地区相比也有较大差距。为了解我市职业卫生技术服务机构现状,我们进行了此项调查。  相似文献   
103.
The objective of this study was to assess the basis for the diminished natural killer (NK) lymphocyte activity of neonates. We found either severely reduced (63% of 68 neonates) or normal (similar to healthy adult) levels of NK activity. The percentages of cord blood mononuclear cells from the two groups of infants that expressed CD16, a differentiation antigen found in NK cells, were similar and within the range found in peripheral blood mononuclear cells of adults. However, infants with low NK activity had reduced numbers of cells in the CD16+56+ subpopulation, whereas the number of these effector cells present in cord blood mononuclear cells from infants with normal NK activity was within the range found in adults. Recombinant interleukin-2, but not recombinant interferon-gamma, normalized the low NK activity of infants in a dose- and time-dependent manner. Analysis of the pattern of target cell susceptibility to lysis, together with the CD16+CD3- phenotype of the precursor and effector lymphocytes, demonstrated that the induced cytotoxicity was mediated by NK cells. In contrast, NK cells from infants with normal cytotoxic levels exhibited a functional response to interleukin-2 and interferon-gamma similar to that of adults. Our results indicate that NK cells in human neonates go through two different maturational stages.  相似文献   
104.
We investigated if orally administered bifidobacteria and/or lactobacilli could be cultured from faeces of infants after antibiotic treatment, when these bacterial species are usually absent. Lyophilized Bifidobacterium longum, strain BB-536, B. breve, strain BB-576, or Lactobacillus acidophilus, strain LAC-343, were used. Doses of 3 x 10(9) cells of one strain, or a mixture of all three strains 3 x 10(9) cells each were fed three times daily at mealtimes to 11 infants aged 0-8 weeks. Treatment was started the first day after antibiotic treatment and was continued for 5 days. The bacterial species were isolated in 9 of 11, 7 of 10 and 2 of 9 specimens obtained on the last day of bifidobacteria or lactobacilli administration, 5 and 15 days thereafter, respectively. No side effects were noted.  相似文献   
105.
106.
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   
107.
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   
108.
. 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   
109.
110.
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   
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