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41.
Introduction and hypothesis Childbirth-related morphological abnormalities or defects of the puborectalis muscle (“avulsion”) can be diagnosed by magnetic
resonance imaging and three-dimensional (3D) ultrasound, but neither method is universally available. In this study, we tested
validity and reproducibility of a new method for diagnosing levator avulsion by 2D translabial ultrasound.
Methods Seventy-five women were examined for major morphological abnormalities of the puborectalis muscle by palpation, 2D and 3D
ultrasound (US). For 2D US, we used an oblique parasagittal translabial approach. The operator using 2D US was blinded against
all other findings.
Results Agreement between observers for diagnosis of avulsion by 2D US was 87% (Cohen’s kappa 0.56, CI 0.33–0.80). Agreement between
tomographic 3D US and 2D US was 87% (kappa 0.61, CI 0.45–0.77).
Conclusions Defects of the puborectalis muscle can be diagnosed with 2D US. The finding of a discontinuity between the hyperechogenic
muscle and the pelvic sidewall is moderately reproducible and agrees moderately well with palpation and 3D US. 相似文献
42.
JME Kovoor RD Thomas HS Chandrashekhar PN Jayakumar S Pillai SK Shankar 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):406-411
Early and non‐invasive evaluation of hydatid infestation of brain and spine is of paramount importance, especially in endemic areas. We present a spectrum of imaging findings in neurohydatidosis with a brief review of literature. 相似文献
43.
PN McDOUGALL PM LOUGHNAN NT CAMPBELL M HOCHMANN BJ TIMMS WW BUTT 《Journal of paediatrics and child health》1995,31(4):292-296
Objective: To report ventilation strategies, survival and complications in 39 outborn infants treated with high frequency oscillatory ventilation (HFOV).
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
Methodology Data were collected prospectively between 1 May 1992 and 31 December 1993 on all infants treated with HFOV who had severe respiratory failure despite optimal conventional ventilation.
Results Twenty-eight out of 39 (72%) survived. Of the 15 infants with birthweights <1500g, eight survived. Best survival rates were for infants with pulmonary interstitial emphysema with air leak (4/5) and for infants of birthweight >1500g with hyaline membrane disease (8/8), and meconium aspiration syndrome (7/7). Three infants deteriorated while on HFOV and required extracorporeal membrane oxygenation. Complications were: (i) development of pulmonary interstitial emphysema (1); (ii) recurrence of pneumothorax (3); (iii) hypotension (2); and (iv) bronchopulmonary dysplasia (9). One of the eight infants weighing <1500g who received HFOV in the first week of life developed periventricular haemorrhage.
Conclusion The initial results of HFOV for severe respiratory failure were encouraging although a learning curve was encountered with its introduction. 相似文献
44.
Au WY Lie AK Kwong YL Shek TW Hawkins BR Lai KN Tang SC Lo CM Fan ST Liu CL Chan GC Chau EM Chiu SW Liang R 《Leukemia & lymphoma》2002,43(7):1403-1407
Post-transplantation lymphoproliferative disease (PTLD) is an unique iatrogenic complication after bone marrow transplantation (BMT) and solid organ transplantation (SOTx). The pattern of EBV related lymphoma in Chinese is different from Caucasians. We surveyed the incidence, clinical and pathological spectrum of PTLD among 541 cases of allogeneic BMT, 145 cases of renal transplant, 35 cases of heart/lung transplantation and 146 cases of orthotopic liver transplantation (OLT). From 1994 to 2001, 13 consecutive cases of PTLD were diagnosed, ranging from disseminated NK cell lymphoma to localized plasmacytoma. Both donor and recipient derived PTLD was documented. Disease was often heralded by cytomegaloviral disease and antithymocyte globulin (ATG) usage. Two cases were diagnosed post-mortem, and six patients died of PTLD at a median of 3 months. Complete and partial remission was only achieved in 3 and 2 cases, respectively, despite a range of treatment (reduced immunosuppression, explantation, radiotherapy, combination chemotherapy, donor lymphocytes, autologous marrow infusion and rituximab). Most responding patients died subsequently of rejection, infection and graft versus host disease (GVHD). The incidence of PTLD is not increased in Chinese patients. However, some patients may be at increased risk, especially mismatched allogeneic BMT, parental OLT (especially involving young infants) and heavy ATG exposure. 相似文献
45.
Dietary zinc deficiency in rats induces hyperplasia in the esophagus and
increases N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor
incidence. Previous work showed a direct relationship between epithelial
cell proliferation and esophageal tumor incidence in rats given multiple
doses of NMBA. We investigated the effects of single low doses of NMBA in
zinc-deficient rats since a single dose of 5.0 mg/kg was reported to be
non-carcinogenic in rats. Zinc-sufficient and deficient rats received a
single i.g. dose of NMBA at 0.5 or 2.0 mg/kg. At week 14, tumor incidence
was 50% with 0.8 +/- 1.0 tumors/rat, and 80% with 2.2 +/- 1.9 tumors/rat,
in deficient groups, D(0.5) and D(2.0), that received the lower and higher
dose, respectively. In addition, two small papillomas were found in one out
of eight untreated zinc-deficient rats. None of the NMBA-treated or
untreated zinc- sufficient rats had any tumors. Esophageal cell
proliferation, as determined by proliferating cell nuclear antigen (PCNA)
immunohistochemistry, showed that, irrespective of NMBA treatment,
deficient esophagi had significant increases in the number of labeled
cells, the total number of cells, and the labeling index, as compared with
zinc-sufficient ones. Mutations in Ha-ras and p53 genes in esophageal
tumors were detected by single strand conformation polymorphism (SSCP)
analysis. DNA sequencing of variant conformers revealed a point mutation
(GGA-->GAA, codon 12) in Ha-ras in 4/5 (80%) and 5/8 (63%) tumors, from
D(0.5) and D(2.0) rats, respectively. Three out of eight tumors from D(2.0)
rats exhibited SSCP mobility shifts within p53 exons 5 and 7: two tumors
(2/8, 25%) had missense mutations and the third, a silent mutation. Of the
two tumors with p53 mutations, one had a double mutation (transition at
codon 164, TCA-->TTA; transversion at codon 241, AGT-->TGT), and the
other tumor, a transition at codon 172 (AGA-->GGA), with amino acid
changes in all cases. In parallel with PCNA expression, elevated p53
expression was associated with hyperplastic and dysplastic regions, as well
as with tumors, in deficient esophagi. In short, these data indicate that
dietary zinc deficiency, with its associated sustained increased cell
proliferation in the esophagus, can drive an otherwise non-tumorigenic dose
of NMBA into a highly tumorigenic one.
相似文献
46.
47.
N-Methyl-1,6-dihydropyridine-2-carbaldoxime hydrochloride, the pro-drug of 2-PAM, was found to be converted in vivo to 2-PAM, rapidly and quantitatively. The significantly changed properties of the pro-2-PAM resulted in a longer biological half-life and a favorable distribution of 2-PAM formed upon its oxidation. No new metabolite was found when pro-2-PAM was administered intravenously; however, a new metabolic product was formed when the pro-drug was given by oral route. 相似文献
48.
Lok IH Lee DT Yip SK Shek D Tam WH Chung TK 《American journal of obstetrics and gynecology》2004,191(2):546-550
OBJECTIVE: The purpose of this study was to evaluate 12-item General Health Questionnaire (GHQ-12) in screening for psychiatric morbidity after miscarriage. STUDY DESIGN: A prospective cohort study was carried out involving 222 patients. Six weeks after miscarriage, the GHQ-12 was applied. Psychiatric "case" or "non-case" was diagnosed by the psychiatrist with use of the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-III-R. The patients were computer randomized into Groups A or B. A receiver operating characteristic (ROC) curve was constructed for Group A. The optimal cutoff value of GHQ-12 was determined, and this value was applied to Group B. The test characteristics were assessed. RESULTS: Twenty-seven patients were found to be psychiatric cases. An ROC with area under curve of 0.93 (95% CI 0.87-0.99, P<.001) was constructed. The best GHQ-12 cutoff score was > or =4 in detecting psychiatric caseness. A sensitivity of 83%, specificity of 90%, positive predictive value of 50%, and negative predictive value of 98% were obtained. CONCLUSION: GHQ-12 is an effective screening tool in detecting psychiatric morbidity after miscarriage. 相似文献
49.
Wang XS Tan TN Shek LP Chng SY Hia CP Ong NB Ma S Lee BW Goh DY 《Archives of disease in childhood》2004,89(5):423-426
Background and Aims: Over the past few decades, the prevalence of asthma has been increasing in the industrialised world. Despite the suggestion of a similar increase in Singapore, the 12 month prevalence of wheeze among schoolchildren in 1994 was 2.5-fold less than that reported in western populations. It was hypothesised that with increasing affluence in Singapore, the asthma prevalence would further increase and approach Western figures. A second ISAAC survey was carried out seven years later to evaluate this hypothesis. Methods: The cross-sectional data from two ISAAC questionnaire based surveys conducted in 1994 (n = 6238) and in 2001 (n = 9363) on two groups of schoolchildren aged 6–7 and 12–15 years were compared. The instruments used were identical and the procedures standardised in both surveys. Results: Comparing data from both studies, the change in the prevalence of current wheeze occurred in opposing directions in both age groups—decreasing in the 6–7 year age group (16.6% to 10.2%) but increasing to a small extent in the 12–15 year age group (9.9% to 11.9%). The 12 month prevalence of rhinitis did not change; there was an increase in the current eczema symptoms in both age groups. Conclusion: The prevalence of current wheeze, a surrogate measure of asthma prevalence, has decreased significantly in the 6–7 year age group. Eczema was the only allergic disease that showed a modest increase in prevalence in both age groups. 相似文献
50.
Shek‐Yuen Kwok Cliff Chi‐Chiu Chung Wilson Wen‐Chieng Tsang Michael Ka‐Wah Li 《Surgical Practice》2004,8(4):115-119
Objective: In laparoscopic colorectal procedures, the presence of peritoneal adhesions caused by previous surgery is one of the most common reasons for conversion and is often associated with increased postoperative morbidity. However, improvements in laparoscopic technique and instruments might, to some extent, help to overcome the adverse effects of peritoneal adhesions. Therefore, the present study was designed to compare and evaluate laparoscopic rectal cancer excision in patients who had had and who had not had previous abdominal surgery. Methods: The present study was a non‐randomized comparison of patients who have had and have not had previous abdominal surgery. Data were extracted from a prospective cohort of patients who had undergone laparoscopic anterior resection for rectal cancer in one particular unit between January 1996 and May 2000. For the purpose of standardization, data on laparoscopic low anterior resection and laparoscopic abdomino‐perineal resection were not used for analysis. The measured outcomes included operation time, blood loss and length of hospital stay as well as complications and conversions. Results: Of the 91 patients recruited for analysis, 26 patients had had previous abdominal surgery (study group), whereas 65 patients had not had previous abdominal surgery (control group). The two groups had a similar age and gender distribution as well as tumour staging. The median operating times of the study group and control group (115 vs 123 min, P = 0.34), their blood loss (122 vs 144 mL, P = 0.30) and lengths of hospital stay (10 vs 11 days, P = 0.66) were similar. The complication rates (23 vs 23%, P = 0.79) and conversion rates (15.4 vs 7.7%, P = 0.55) were also similar between the two groups. Conclusion: Laparoscopic resection for rectal cancer in patients who have had previous abdominal surgery is technically safe and produces similar results to those who have not had previous abdominal surgery. 相似文献