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排序方式: 共有1316条查询结果,搜索用时 15 毫秒
1.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
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A fatality due to the ingestion of isoniazid, a tuberculostatic agent, is presented. Isoniazid was extracted by a single step extraction procedure, derivatized with trifluoroacetic anhydride, and identified and quantified by gas chromatography/mass spectrometry (GC/MS). The distribution of isoniazid was as follows: heart blood 43 mg/L, subclavian blood 94 mg/L, urine 470 mg/L, bile 900 mg/L, liver 650 mg/Kg, kidney 110 mg/Kg, and stomach contents 4 mg.  相似文献   
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Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced thoracic cavity. In the most common subtype (TD1), femurs are curved, while in TD2, straight femurs are associated with cloverleaf skull. Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene were identified in both subtypes. While TD2 was accounted for by a single recurrent mutation in the tyrosine kinase 2 domain, TD1 resulted from either stop codon mutations or missense mutations in the extracellular domain of the gene. Here, we report the identification of FGFR3 mutations in 25/26 TD cases. Two novel missense mutations (Y373C and G370C) were detected in 8/26 and 1/26 TD1 cases respectively. Both mutations created cysteine residues in the juxta extramembrane domain of the receptor. Sixteen cases carried the previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically homogeneous condition and give additional support to the view that newly created cysteine residues in the extracellular domain of the protein play a key role in the severity of the disease.   相似文献   
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Lethal white foal syndrome (LWFS) is a congenital anomaly of horses characterized by a white coat colour and aganglionosis of the bowel, which is similar to Hirschsprung disease (HSCR). We decided to investigate possible mutations of the endothelin-B receptor gene ( EDNRB ) in LWFS as recent studies in mutant rodents and some patients have demonstrated EDNRB defects. First, we identified a full-length cDNA for horse EDNRB . This cDNA fragment contained a 1329 bp open reading frame which encoded 443 amino acid residues. The predicted amino acid sequence was 89, 91 and 85% identical to human, bovine and mouse as well as rat EDNRB respectively, but only 55% identical to the human, bovine and rat endothelin A receptor (EDNRA). Secondly, sequence analysis, together with allele-specific PCR and the amplification- created restriction site (ACRS) technique, revealed a dinucleotide TC-- >AG mutation, which changed isoleucine to lysine in the predicted first transmembrane domain of the EDNRB protein. This was associated with LWFS when homozygous and with the overo phenotype when heterozygous.   相似文献   
8.
Trichotillomania, an irresistible impulse to pull out one's own hair, is a chronic psychiatric illness that causes severe discomfort, interferes with daily activities, and leads to social isolation. Treatment is usually unsatisfactory. Thirteen women with severe trichotillomania completed a 10-week double-blind, crossover trial of clomipramine, a new tricyclic antidepressant agent with selective antiobsessional effects, and desipramine, a standard tricyclic antidepressant. Treatment with clomipramine resulted in significantly greater improvement in symptoms than desipramine, as indicated by physicians' ratings of the women's clinical progress on a scale in which lower scores indicate improvement (mean [+/- SD] scores: at base line, 10.0; after desipramine treatment, 8.7 +/- 2.4; after clomipramine treatment, 4.7 +/- 3.1; P = 0.006) and by scores on a trichotillomania-impairment scale, in which higher scores indicate greater impairment (at base line, 6.8 +/- 1.7; after desipramine treatment, 6.2 +/- 1.7; after clomipramine treatment, 4.2 +/- 2.7; P = 0.03). The severity of symptoms (mean base-line score, 15.9 +/- 3.8) was reduced more by clomipramine (10.6 +/- 6.4) than by desipramine (14.4 +/- 3.9). The patients reported that the compulsion decreased in intensity and that they were more able to resist the urge to pull out their hair during treatment with clomipramine. We conclude that clomipramine appears to be effective in the short-term treatment of trichotillomania.  相似文献   
9.
Childhood rituals: normal development or obsessive-compulsive symptoms?   总被引:1,自引:0,他引:1  
The symptoms of obsessive compulsive disorder (OCD) have been viewed as extreme variants of normal developmental rituals and superstitiousness; however, difference in timing, content, and severity argue against this continuum. In a systematic comparison of 38 children with severe primary OCD and 22 matched normal controls, parents were interviewed about their child's early developmental rituals and current superstitions. Children were asked about superstitious beliefs. Children with OCD did not differ significantly from controls in number or type of superstitions. However, parents of the OCD children reported significantly more "marked" patterns of early ritualistic behavior than did parents of normal controls. When behaviors resembling primary OCD symptoms were excluded, other rituals did not differ leaving open the possibility that such behaviors were early manifestations of the disorder. Only a prospective study can determine whether these results reflect preclinical OCD or are an artifact of biased recall.  相似文献   
10.
Hsiao  MH; Yu  AL; Yeargin  J; Ku  D; Haas  M 《Blood》1994,83(10):2922-2930
We have previously reported that greater than 60% of human leukemic T- cell lines possess mutations in the p53 tumor suppressor gene. To determine whether T-cell acute lymphoblastic leukemia (T-ALL) patient samples possess p53 mutations, we screened peripheral blood-and bone marrow-derived leukemia samples, taken at diagnosis and at relapse, for p53 mutations. Exons 4 through 9 and selected intron regions of the p53 gene were analyzed using polymerase chain reaction-single-strand conformation polymorphism and direct sequencing. p53 mutations were found in 0 of 15 T-ALL diagnosis samples, as compared with 10 of 36 (28%) T-ALL relapse samples. To determine whether p53 mutations play a role in the recurrence (relapse) of T-ALL, two special groups of T-ALL patients were studied: (1) a group of 8 relapse patients whose disease was refractory to chemotherapeutic treatment, and (2) a group of 6 "paired" T-ALL cell samples from patients for whom we possess both diagnosis and relapse samples. Three of 8 relapsed patients (37.5%) whose disease was refractory to the reinduction of remission by chemotherapy possessed missense mutations of the p53 gene. All 3 cases had mutations in exon 5. Among the paired samples, 3 of 6 patients harbored p53 mutations at disease recurrence, but possessed only wild- type p53 alleles at diagnosis. One case had mutation on exon 4, 1 case in exon 5, and 1 case in exon 8 with loss of heterozygosity. These data clearly indicate that recurrence of T-ALL is associated with missense mutations in p53. Our results indicate that (1) mutations of p53 do occur in T-ALL in vivo, and such mutations are associated with the relapse phase of the disease; and (2) p53 mutation is involved in the progression of T-ALL. This conclusion is supported by our observation that the introduction of T-ALL-derived mutant p53 expression constructs into T-ALL cell lines further increases their growth rate in culture, enhances cell cloning in methylcellulose, and increases tumor formation in nude mice.  相似文献   
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