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11.
Intravaginal misoprostol has been shown to be effective forcervical priming before a surgically induced abortion. The objectivewas to investigate the effectiveness of oral misoprostol incervical dilatation prior to vacuum aspiration between the 6thand 12th weeks of pregnancy. The results showed that in nulliparouspatients, the median cervical dilatation in the treatment group(7.8 mm) was significantly greater than that in the placebogroup (3.7 mm). In multiparous patients, the difference wasalso statistically significant (9.8 versus 6.0 mm). The easeof dilatation, assessed subjectively by the operating surgeons,was significantly improved in the treatment group. There wasalso a significant reduction in the duration of the operationand in the mean blood loss in the treatment group. The side-effectsencountered in the treatment group were mild and well acceptedby the women. Oral misoprostol is an effective and safe methodfor cervical dilatation prior to vacuum aspiration in firsttrimester pregnancy.  相似文献   
12.
The bioavailability of citrate from two different preparations of potassium citrate was examined in eighteen normal volunteers during three phases of study. After stabilization on a constant metabolic diet, subjects took a single dose of placebo, "slow-release" potassium citrate tablets (60 meq) or rapid-release liquid potassium citrate preparation (60 meq). Timed urine specimens were collected for 24 hours and analyzed for citrate, potassium, and pH. Similar biochemical findings were observed following administration of the two different preparations with the onset and decline of changes being slightly more rapid for the liquid potassium citrate than the tablet preparation. These equivalent bioavailability data indicate that the liquid preparation is a comparable therapeutic alternative to the tablet form.  相似文献   
13.
Chromosome 2 (2p16) abnormalities in Carney complex tumours   总被引:6,自引:0,他引:6       下载免费PDF全文
Carney complex (CNC) is an autosomal dominant multiple endocrine neoplasia and lentiginosis syndrome characterised by spotty skin pigmentation, cardiac, skin, and breast myxomas, and a variety of endocrine and other tumours. The disease is genetically heterogeneous; two loci have been mapped to chromosomes 17q22–24 (the CNC1 locus) and 2p16 (CNC2). Mutations in the PRKAR1A tumour suppressor gene were recently found in CNC1 mapping kindreds, while the CNC2 and perhaps other genes remain unidentified. Analysis of tumour chromosome rearrangements is a useful tool for uncovering genes with a role in tumorigenesis and/or tumour progression. CGH analysis showed a low level 2p amplification recurrently in four of eight CNC tumours; one tumour showed specific amplification of the 2p16-p23 region only. To define more precisely the 2p amplicon in these and other tumours, we completed the genomic mapping of the CNC2 region, and analysed 46 tumour samples from CNC patients with and without PRKAR1A mutations by fluorescence in situ hybridisation (FISH) using bacterial artificial chromosomes (BACs). Consistent cytogenetic changes of the region were detected in 40 (87%) of the samples analysed. Twenty-four samples (60%) showed amplification of the region represented as homogeneously stained regions (HSRs). The size of the amplicon varied from case to case, and frequently from cell to cell in the same tumour. Three tumours (8%) showed both amplification and deletion of the region in their cells. Thirteen tumours (32%) showed deletions only. These molecular cytogenetic changes included the region that is covered by BACs 400-P-14 and 514-O-11 and, in the genetic map, corresponds to an area flanked by polymorphic markers D2S2251 and D2S2292; other BACs on the centromeric and telomeric end of this region were included in varying degrees. We conclude that cytogenetic changes of the 2p16 chromosomal region that harbours the CNC2 locus are frequently observed in tumours from CNC patients, including those with germline, inactivating PRKAR1A mutations. These changes are mostly amplifications of the 2p16 region, that overlap with a previously identified amplicon in sporadic thyroid cancer, and an area often deleted in sporadic adrenal tumours. Both thyroid and adrenal tumours constitute part of CNC indicating that the responsible gene(s) in this area may indeed be involved in both inherited and sporadic endocrine tumour pathogenesis and/or progression.  相似文献   
14.
A monoclonal antibody, 16B-13, derived from the immunization of BALB/c mice with a lung tumor line, immunoprecipitates a common tumor-associated molecule with an apparent mol. wt of 37,000 from lactoperoxidase-ionated lung carcinoma, colon carcinoma, gastric carcinoma, brest carcinoma, melanoma and lymphona cells, but not from normal fibroblasts. Analysis by two-dimensional gel electrophoresis of the cell surface-labeled 16B-13 antigen from a colorectal and a melanoma cell line reveals four components with similar mol. wts but with different isoelectric points. The antigen purified froma a colorectal carcinoma cell line by immunoaffinity chromatography was shown to be a 37,000 mol. wt polypeptide similar to that obtained by the lactoperoxidase-labeling procedure. However, the purified antigen from the melanoma cell line shows the presence of a 65,000 mol. wt polypeptide and the loss of the 37,000 mol. wt component as detected by Comassie blue staining and immunoprecipitation.  相似文献   
15.
Receptor autoradiography was used in guinea-pig heart to locate binding sites for the beta-adrenoceptor ligand (-)[125I]cyanopindolol (CYP) resistant to blockade by the beta-adrenoceptor antagonist (-)-propranolol (1 microM). Highly localized binding was observed to regions closely associated with the sinoatrial node, atrioventricular node and bundle of His but was not observed on myocardial, pacemaker, conducting cells or adipose tissue. Free [125I] also bound to identical sites. Binding was enhanced in the presence of ascorbic acid but was completely inhibited by (-)-isoprenaline (100 microM), serotonin (5-HT) (10 microM) and phentolamine (10 microM).  相似文献   
16.
The bioavailability, biochemical effects, and safety of a slow-release preparation of sodium fluoride were examined. In 8 normal volunteers, a single administration of slow-release sodium fluoride (25 mg) caused a slow rise and gradual decline in serum fluoride concentration, thus avoiding sharp peaks produced by a rapid-release preparation. In 37 patients with postmenopausal osteoporosis, serum fluoride concentration was kept within the "therapeutic window" (95-100 ng/ml) during long-term intermittent sodium fluoride (slow-release) therapy (25 mg twice/day, given for 3 months in each 5-month cycle over five cycles). Serum fluoride was also kept within the therapeutic window in 64 patients who took sodium fluoride (slow release) continuously over 12 months. Serum osteocalcin concentration increased progressively during fluoride treatment (correlation coefficient of 0.88, p less than .001 for the relationship between serum osteocalcin and duration of therapy). Side effects to slow-release sodium fluoride therapy, assessed in 101 patients at two study sites, were minor and included diarrhea in 2 patients, nausea in 2 patients, abdominal pain and cramping in 2 patients, foot pain in 2 patients, and joint pain in 6 patients. Thus, slow-release sodium fluoride confers desired level of fluoride in serum, while providing safety of usage.  相似文献   
17.
PurposeTo identify influence of different values of age and abnormal bowel length in HD patients selected for single stage TERPT which affects the technique of surgery.MethodsThis observational study was carried out for over 2.5 years. All children younger than 14 years old with clinical suspicion for HD, typical transitional zone (TZ) on contrast enema (CE) distal to splenic flexure, preoperative diagnosis approved by full thickness biopsy, no previous surgical history and no urgency were included. The distance between the anus and TZ was considered as aganglionic length on CE. Biopsy was taken from distal to proximal of resected bowel to reach circumferentially normal innervated bowel. Paired sample Student's t-test, Pearson correlation test, receiver operating characteristic (ROC) analysis were performed.ResultsForty-eight patients were enrolled in this study. Measured mean for aganglionic bowel length on CE and pathology were 33.5 ± 17.1 cm and 56.8 ± 33.5 cm, respectively (p < 0.01). Correlation coefficient (R) and coefficient of determination (R2) were 0.632 and 40%, respectively (p < 0.01). The difference between radiologic and pathologic measurements in females was higher than males (mean: 29.3 vs 21.9 cm) but was not statistically significant (p = 0.75). There was statistically significant difference between CE and pathologic results in the infants younger than 10 months (p = .004). Abnormal bowel length equal to 52 cm predicted requirement of laparoscopy assistance/laparotomy with 75% sensitivity and 85% specificity.ConclusionOur investigation showed it is safe to attempt for single stage TERPT when aganglionic length on CE is less than 52 cm and the child with HD is older than 10 months. Chance of requiring additional laparotomy or laparoscopy assistance is low in these patients.Type of studyStudy of diagnostic test.Level of evidenceLevel II.  相似文献   
18.
OBJECTIVE: Our goal was to determine the appearance of motion artifact when imaging an anthropomorphic breast phantom using a digital slot-scanning system compared with a screen-film system. MATERIALS AND METHODS: Digital and screen-film images were obtained during both brief and continuous manually induced motion of an anthropomorphic phantom in four directions. Continuous motion was further characterized using a syringe pump to induce motion artifact. RESULTS: On screen-film images, brief motion caused degradation of the entire image, simulating a double exposure. Conversely, on digital images using a slot-scanning system, brief motion caused degradation of only a small portion of the image. Continuous motion resulted in smearing of phantom details with both systems, although the smearing was more strongly influenced by the direction of motion when the slot-scanning system was used. With the slot-scanning system, motion in the direction of the detector sweep resulted in elongated distortion, whereas motion in the opposite direction resulted in foreshortening; diagonal smearing was seen with perpendicular phantom motion. The magnitude of distortion for continuous motion at a set velocity was substantially less with the slot-scanning system. CONCLUSION: Motion artifact with a slot-scanning direct digital mammography unit differs significantly from that seen with a conventional screen-film unit and, despite a relatively long overall exposure, may prove to be less of a problem than with conventional units because any given part of an object is exposed only briefly.  相似文献   
19.
20.
A simple, step-by-step approach to diagnosis and medical treatment of stone disease is described. It uses urinary stone risk profile obtained before and after dietary modification, history, and minimum diagnostic tests. For each abnormal stone risk factor, potential causes are discussed and treatment options are presented. The article concludes with diagnosis and treatment of combined disturbances.  相似文献   
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