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31.
32.
Pain in chronic pancreatitis(CP) shows similarities with other visceral pain syndromes(i.e.,inflammatory bowel disease and esophagitis),which should thus be managed in a similar fashion.Typical causes of CP pain include increased intrapancreatic pressure,pancreatic inflammation and pancreatic/extrapancreatic complications.Unfortunately,CP pain continues to be a major clinical challenge.It is recognized that ongoing pain may induce altered central pain processing,e.g.,central sensitization or pro-nociceptive pain modulation.When this is present conventional pain treatment targeting the nociceptive focus,e.g.,opioid analgesia or surgical/endoscopic intervention,often fails even if technically successful.If central nervous system pain processing is altered,specific treatment targeting these changes should be instituted(e.g.,gabapentinoids,ketamine or tricyclic antidepressants).Suitable tools are now available to make altered central processing visible,including quantitative sensory testing,electroencephalograpy and(functional) magnetic resonance imaging.These techniques are potentially clinically useful diagnostic tools to analyze central pain processing and thus define optimum management approaches for pain in CP and other visceral pain syndromes.The present review proposes a systematic mechanism-orientated approach to pain management in CP based on a holistic view of the mechanisms involved.Future research should address the circumstances under which central nervous system pain processing changes in CP,and how this is influenced by ongoing nociceptive input and therapies.Thus we hope to predict which patients are at risk for developing chronic pain or not responding to therapy,leading to improved treatment of chronic pain in CP and other visceral pain disorders.  相似文献   
33.
Ertzner  TW; Powers  TA 《Radiology》1985,154(2):507-512
A technique for the noninvasive diagnosis of pseudoaneurysms is described. This method employs in vivo labeling of red blood cells with Tc-99m to allow better delineation of the vascular anatomy than standard radionuclide angiography. Four cases are illustrated.  相似文献   
34.
This prospective study compared images obtained with a photostimulable imaging plate with matched images obtained with a conventional screen-film combination in 26 patients undergoing intraoperative arteriography. Diagnostic accuracy of the two techniques was assessed objectively, and image quality was assessed subjectively. In 16 patients (62%), the radiation exposure was reduced by 50% for the imaging plate technique by decreasing the mAs level generally used for the screen-film combination. Because of the dynamic range of the imaging plate system, no repeat examinations were necessary, while 12% of the screen-film studies had to be repeated because of over- or under-penetration. Imaging plate studies required 6% more time for processing than screen-film studies. Receiver-operating-characteristic analysis indicated no difference in diagnostic accuracy between the two imaging techniques. Subjective evaluation also revealed no difference in observer preference for imaging plate or screen-film studies. The imaging plate technique is an excellent alternative to screen-film studies in the operating room.  相似文献   
35.
The gene for autosomal recessive spinal muscular atrophy (SMA) has been mapped to 5q12 in a region that contains repeated markers and genes. Three cDNAs that detect deletions in SMA patients have been reported. One of these, the survival motor neuron (SMN) cDNA, is encoded by two genes (SMNT and SMNC) which are distinguished by base changes in exons 7 and 8. Exon 7 of the SMNT gene is not detectable in approximately 95% of SMA cases, due either to deletion or sequence conversion. There is limited information on the mutations in SMA patients that have detectable SMNT, these are critical for confirmation of SMNT as the SMA gene. Using SSCP analysis of the SMN exons we screened our SMA patients that possess at least one intact SMNT allele for mutations in SMNT. We identified one type I SMA patient with an 11 bp duplication in exon 6 which causes a frameshift and premature termination of the deduced SMNT protein. Dosage and SSCP analysis of SMNT in this family indicated that the father contributed a SMNT-deleted allele to the affected child whereas the mother passed on the 11 bp exon 6 duplication SMNT allele. Analysis of RNA by RT-PCR conclusively demonstrated that the 11 bp duplication is associated with the SMNT locus and not SMNC. This mutation provides strong support for SMN as the SMA-determining gene and indicates that disruption of SMNT on its own is sufficient to produce a severe type I SMA phenotype.   相似文献   
36.
时岩  孙林潮  高天文 《医学争鸣》1999,20(9):826-826
0 引言 东方人接受皮肤磨削术治疗后色素沉着的发生率明显高于西方人.尽管采用了目前被认为是最适宜亚洲人的铒激光治疗,色素沉着仍可发生.因此,在实施该手术治疗前应严格掌握适应证,制定严密的预防治疗措施,使得色素沉着的发生率降至最低,从而最大限度的防止医疗纠纷的发生.1 对象和方法1.1 对象 21例患者,男2例,女19例,平均年龄29.2(08~48)岁.皱纹祛除8例,浅表疤痕7例,浅咖啡斑、黑子5例,不良纹眉1例.铒激光其它适应证:①老年斑;②细小皱纹;③“白皮肤”雀斑;④痤疮后疤痕⑤色素减退…  相似文献   
37.
Increased emphasis on strict glycaemic control of insulin dependent diabetes mellitus (IDDM) in young patients may be expected to cause increases in rates of significant hypoglycaemia. To evaluate whether this is the case for a large population based sample of IDDM children and adolescents rates of severe (coma, convulsion) and moderate (requiring assistance for treatment) hypoglycaemia were studied prospectively over a four year period. A total of 709 patients were studied yielding 2027 patient years of data (mean (SD) age: 12.3 (4.4); range 0-18 years, duration IDDM: 4.9 (3.8) years). Details of hypoglycaemia were recorded at clinic visits every three months when glycated haemoglobin (HbA1c) was also measured. Overall the incidence of severe hypoglycaemia was 7.8 and moderate was 15.4 episodes/100 patient years. Over the four years mean (SD) clinic HbA1c steadily fell from 10.2 (1.6)% in 1992 to 8.8 (1.5)% in 1995. In parallel with this there was a dramatic increase in the rate of hypoglycaemia, especially in the fourth year of the study, when severe hypoglycaemia increased from 4.8 to 15.6 episodes/100 patient years. This increase was particularly marked in younger children (< 6 years) in whom severe hypoglycaemia increased from 14.9 to 42.1 episodes/100 patient years in 1995. It is concluded that attempts to achieve improved metabolic control must be accompanied by efforts to minimise the effects of significant hypoglycaemia, particularly in the younger age group.  相似文献   
38.
Despite its apparent benefits, high-dose ibuprofen has been infrequently applied to children with cystic fibrosis. We have noted a decrease in the use of high-dose ibuprofen at our pediatric cystic fibrosis center during the past decade. In this retrospective study, we examined our clinical experience with high-dose ibuprofen and other anti-inflammatory drugs in cystic fibrosis patients. The medical records of all patients, ages 5 to 18 years, followed at the cystic fibrosis center from 1995 to 2002, were reviewed and children were classified into two cohorts: ibuprofen-treated and untreated groups. Patterns of ibuprofen use and pharmacokinetics in treated patients, and for patients who discontinued ibuprofen, the reasons for stopping the medication, including adverse effects, were assessed. Pulmonary function decline and hospitalization rates for each group were compared, examining both intent to treat and patients who continued therapy for at least 4 years. Nearly half of the patients in our pediatric cystic fibrosis center who were prescribed with high-dose ibuprofen discontinued therapy due to adverse events, not because of poor adherence or patient choice. Neither use of high-dose ibuprofen nor its cessation resulted in a significant change in the rate of decline in pulmonary function or influenced hospitalization rates.  相似文献   
39.
药物代谢分型的研究进展   总被引:5,自引:0,他引:5  
目的:为了促进药物代谢分型研究在临床上的深放。方法:综述近几年具遗传多态性代谢酶的探针药物、代谢分型方法以及影响因素。介绍“Cooktail”分型法。比较代谢分型与基因分型两种分型方法。结果:疾病、并用药物、探药剂量、样本处理方法、服药依从性是代谢分型的主要影响因素。结论:药物代谢分型能指导临床安全合理有效地用药。基因分型与代谢分型各有优点,应灵活应用。“Cooktail”分型方法具有独特的优越性和发展前景,应大力开展在特殊群体中的代谢分型研究。  相似文献   
40.
We have targeted the serpin enzyme complex receptor for gene transfer in human hepatoma cell lines using peptides < 30 amino acids in length which contain the five amino acid recognition sequence for this receptor, coupled to poly K of average chain length 100 K, using the heterobifunctional coupling reagent sulfo-LC SPDP. The number of sulfo-LC SPDP modified poly-L-lysine residues, as well as the degree of peptide substitution was assessed by nuclear magnetic resonance spectroscopy. Conjugates were prepared in which 3.5%, 7.8% or 26% of the lysine residues contained the sulfo-LC SPDP moiety. Each of these conjugates was then coupled with ligand peptides so that one in 370, one in 1039, or one in 5882 lysines were substituted with receptor ligand. Electron microscopy and atomic force microscopy were used to assess complex structure and size. HuH7 human hepatoma cells were transfected with complexes of these conjugates with the plasmid pGL3 and luciferase expression measured 2 to 16 days after treatment. All the protein conjugates in which 26% of the K residues were modified with sulfo-LC SPDP were poor gene transfer reagents. Complexes containing less substituted poly K, averaged 17 +/- 0.5 nm in diameter and gave peak transgene expression of 3-4 x 10(6) ILU/mg which persisted (> 7 x 10(5) ILU) at 16 days. Of these, more substituted polymers condensed DNA into complexes averaging 20 +/- 0.7 nm in diameter and gave five-fold less luciferase than complexes containing less substituted conjugates. As few as eight to 11 ligands per complex are optimal for DNA delivery via the SEC receptor. The extent of substitution of receptor-mediated gene transfer complexes affects the size of the complexes, as well as the intensity and duration of transgene expression. These observations may permit tailoring of complex construction for the usage required.  相似文献   
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