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排序方式: 共有421条查询结果,搜索用时 15 毫秒
1.
E Tsoi S Akmal L Geerts B Jeffery K H Nicolaides 《Ultrasound in obstetrics & gynecology》2006,27(4):368-372
OBJECTIVE: In women presenting with threatened preterm labor, both fetal fibronectin and sonographic measurement of cervical length have been shown to distinguish between true and false labor. The aim of this study was to determine whether the combination of both tests provides a better prediction than the individual tests alone. METHODS: We examined 195 women with singleton pregnancies presenting at 24-36 (median 31) weeks of gestation with regular and painful uterine contractions, intact membranes and cervical dilatation of less than 3 cm. On admission to the hospital fetal fibronectin positivity in cervicovaginal secretions was determined and transvaginal sonographic measurement of cervical length was carried out. The results were not made available to the attending obstetrician. The primary outcome measure was delivery within 7 days of presentation. RESULTS: Delivery within 7 days occurred in 51.4% (18 of 35) of those with cervical length below 15 mm and 0.6% (1 of 160) of those with cervical length of 15 mm or more, in 21.2% (18 of 85) of the fibronectin positive group and in 0.9% (1 of 110) of the fibronectin negative group. There was a significant association between cervical length and the incidence of fibronectin positivity (r = -0.921, P = 0.003). Logistic regression analysis demonstrated that the only significant contributor to the prediction of delivery within 7 days was cervical length, with no significant contribution from fibronectin positivity, ethnic origin, maternal age, gestational age, body mass index, parity, previous history of preterm delivery, cigarette smoking, or use of tocolytics. CONCLUSIONS: In women with threatened preterm labor assessment of fetal fibronectin in cervicovaginal secretions does not improve the prediction of delivery within 7 days provided by the sonographic measurement of cervical length. 相似文献
2.
OBJECTIVE: To investigate the interobserver agreement on the intrapartum ultrasonographic definition of the fetal occipital position. METHODS: In 60 singleton pregnancies in labor at term the fetal occipital position was determined by transabdominal ultrasound by two appropriately trained sonographers who were not aware of each other's findings. The Bland-Altman plot was performed and the 95% limits of agreement were calculated. Logistic regression analysis was used to investigate the association between complete agreement in the fetal occipital position between the two observers and maternal and labor characteristics. RESULTS: The two observers had complete agreement on the fetal occipital position in 22/60 (36.7%) cases and disagreement by 15 degrees and 30 degrees in 31 (51.7%) and seven (11.6%) cases, respectively. The mean of the differences between the two observers was 0.25 degrees and the 95% limits of agreement were -28.9 degrees (-32.2 degrees to -25.6 degrees) to 29.4 degrees (26.1 degrees to 32.7 degrees). There were no significant associations between complete agreement and maternal and labor characteristics. CONCLUSION: The interobserver agreement on sonographically determined fetal occipital position during labor is within 15 degrees in nearly 90% of cases and within 30 degrees in all cases. 相似文献
3.
Reversible hepatic dysfunction associated with rhabdomyolysis 总被引:2,自引:0,他引:2
Hepatic dysfunction was observed in 34 patients with nontraumatic rhabdomyolysis. The serum levels of lactic dehydrogenase were markedly elevated in all patients. The peak values occurred within 72 h of hospitalization. There was no significant difference among patients with (9,044 +/- 1,154 U/l) and without acute renal failure (ARF; 9,125 +/- 3,067 U/l). Similarly, marked elevation in both alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were observed within 72 h after admission to the hospital. They were significantly higher in patients with ARF (ALT: 4,718 +/- 785 vs. 2,496 +/- 927 U/l, p less than 0.01; AST: 3,635 +/- 820 vs. 1,352 +/- 624 U/l, p less than 0.01). Hyperbilirubinemia was noted in 13 of 22 (60%) patients with ARF and in 5 of the 12 (41%) of those without ARF. Serum levels of bilirubin ranged from 2.6 to 14.3 mg/dl. Prothrombin time was prolonged in 4 of 12 (33%) without ARF and in 14 of 22 (63%) of patients with ARF. This abnormality lasted from 1 to 13 days. The magnitude and duration of hyperbilirubinemia and abnormal prothrombin time were similar in patients with and without ARF. Hepatic dysfunction appears to occur in about 25% of patients with rhabdomyolysis. The pathogenesis of these abnormalities is not well defined and may be multifactorial. Hyperpyrexia, hypotension and proteases released from injured muscle may each or all be contributory. These hepatic derangements are reversible. 相似文献
4.
Chetan Anand Akmal Pasha M. D. Swetha Putte Gowda B. E. Amitha Rani N. G. K. Karanth 《Food and Agricultural Immunology》2007,18(1):39-51
A polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA) method was developed for the N-methylcarbamate insecticide bendiocarb (2,2-dimethyl-1,3-benzodioxol-4-yl methylcarbamate). Two novel haptens having dimethylbenzodioxyl and dimethylbenzofuranyl groups connected to oxyacetyl-γ-aminobutanoic acid and oxyacetyl-β-alanine spacer arm respectively were synthesised. The first hapten was conjugated to carrier proteins to make antigens that were used to raise polyclonal antibodies in rabbits. The antibodies specifically recognised bendiocarb and its metabolite 2,2-dimethyl-1,3-benzodiox-4-ol with an IC50 value of 9 ppb (ng ml-1). The assay was standardised using the competitive ELISA format at 0.0625 µg antibody concentration and at 1/10k pesticide-HRP dilution. Matrix effect studies were carried out in four vegetable and cereal food samples. Matrix effect elimination in cabbage, cauliflower and rice was achieved by simple dilution of the extract. Five different approaches were attempted to achieve matrix clean up in paddy rice. C-18 column and gel permeation column chromatography (GPC) helped in the matrix removal. The spike and recovery studies for all the four food samples gave a recovery in the range of 75-95%, thus indicating the efficiency of the matrix elimination procedures developed. 相似文献
5.
Alliance governance is a form of governance developed in industry settings and more recently applied to healthcare. The core idea behind alliance governance is to involve the many stakeholders in the system to collaboratively develop a joint programme that promotes an integrated and whole of systems approach to care. Little is known about the model in healthcare, nor what those involved in an alliance should be focused upon. Using a modified Delphi method, this research presents a set of components that research participants agreed should underpin development of an effective alliance governance arrangement.These characteristics include a systems perspective—a truly shared governance protocol based on a shared vision and a common purpose; performance measurement—collecting and using real-time data that depicts the realities of an end-to-end system to establish better and more achievable goals based on alliance performance; a relational perspective to promote trust, respect and collaboration amongst alliance members, who historically have been competing for contracts and resources; structural changes that enable and promote a shared governance system; and, finally, equity and inclusion to ensure a diverse alliance which promotes diversity of ideas, and involvement of all stakeholders in the decision making process. This research is relevant to policymakers seeking to develop effective alliance-type arrangements as well as to those involved in the practice of alliance governance. 相似文献
6.
A retrospective clinicopathological study of 37 patients with chordoma: a danish national series 总被引:1,自引:0,他引:1
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Purpose. There are, in general, few published series on chordoma. It is a rare disease and further data are still needed.Patients/methods. The data of 37 patients with chordoma were retrospectively analyzed. Treatment was surgical excision in 11, radical radiotherapy in 9 and a combination of the two in 16 cases. The male to female ratio was 2.7 : 1. Median age was 59 years (range 1-89 years).Results. The most common symptoms at diagnosis were pain (98%), neurological disturbances (42%) and incontinence (33%). The tumours were located in the sacro-coccygeal region in 68%, the spheno-occipital region in 16% and the vertebrae in 16% of the patients. Median tumour.size was 7 cm (range 1-30 cm). Local recurrence occurred in 21/36 treated cases and distant metastases developed in eight patients (23%). The median time to recurrence/progression after primary treatment was 2 years (range 1-10 years). The actuarial 5-year rates of overall, progression-free and symptom-free survival were 40%, 31% and 20%, respectively. The corresponding 10-year rates were 26%, 21% and 14%, respectively. At the time of analysis, seven patients were alive, six without evidence of disease. Four of the six patients without active disease were symptom free. A univariate analysis showed that age, sex, tumour size, histopathology, surgical safety margin, treatment modality and radiation dose did not significantly affect overall, progression-free or symptom-free survival. Only turnout site had a prognostic value with turnouts in the spheno-occipital region carrying the worst prognosis.Discussion. We conclude that effective treatment against chordomas is still lacking and a prospective multi-institutional registration study may provide more information on the optimal work-up and treatment of this rare disease. 相似文献
7.
Akmal Safwat Yasser Bayoumy Nahla El-Sharkawy Khaled Shaaban Osman Mansour Azza Kamel 《Radiotherapy and oncology》2003,69(1):33-36
In a group of 35 patients with relapsed and/or chemo-resistant non-Hodgkin's lymphoma (NHL), low-dose total body irradiation (LTBI) (+involved-field radiotherapy to bulky sites) achieved a complete remission rate of 29%, 2-years progression-free survival of 32% and a median progression-free survival of 12 months. The 2-year survival was 42% and the median survival was 17 months. Immuno-staining and flow cytometry of peripheral blood in 14 patients showed that LTBI leads to a significant increase in the percentage of CD4+ cells with a consequent significant increase in the CD4+/CD8+ ratio. High lymphocytic percent and a high percentage of CD4+ cells before LTBI were significantly correlated with longer response duration and overall survival. These data may suggest that the palliative potential of LTBI should be investigated as an alternative to chemotherapy in NHL patients. The pre-treatment percentage of lymphocytes and CD4+ cells may be used as predictors for response to LTBI. 相似文献
8.
Sook Yee Hor Mariam AhmadElham Farsi Mun Fei YamMohd Akmal Hashim Chung Pin LimAmirin Sadikun Mohd. Zaini Asmawi 《Regulatory toxicology and pharmacology : RTP》2012
Recently, the fruits of Hylocereus polyrhizus, known as red dragon fruit, have received much attention from growers worldwide. However, there is little toxicological information regarding the safety of repeated exposure to these fruits. The present study evaluated the potential toxicity of a methanol extract of H. polyrhizus fruit after acute and subchronic administration in rats. In the acute toxicity study, single doses of fruit extract (1250, 2500 and 5000 mg/kg) were administered to rats by oral gavage, and the rats were then monitored for 14 days. In the subchronic toxicity study, the fruit extract was administered orally to rats at doses of 1250, 2500 and 5000 mg/kg/day for 28 days. There was no mortality or signs of acute or subchronic toxicity. There was no significant difference in body weight, relative organ weight or hematological parameters in the subchronic toxicity study. Biochemical analysis showed some significant changes, including creatinine, globulin, total protein and urea levels. No abnormality of internal organs was observed between treatment and control groups. The lethal oral dose of the fruit extract is more than 5000 mg/kg and the no-observed-adverse-effect level (NOAEL) of the extract for both male and female rats is considered to be 5000 mg/kg per day for 28 days. 相似文献
9.
Hammad Ahmed Shah Moncef L. Nehdi Muhammad Imtiaz Khan Usman Akmal Hisham Alabduljabbar Abdullah Mohamed Muhammad Sheraz 《Materials》2022,15(15)
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete. 相似文献
10.
Fabian Doerr Akmal M. A. Badreldin Ferzen Can Ole Bayer Thorsten Wahlers 《Scandinavian cardiovascular journal : SCJ》2014,48(2):111-119
Objectives. Cardiac surgery patients are excluded from SAPS2 but included in SAPS3. Neither score is evaluated for this exclusive population; however, they are used daily. We hypothesized that SAPS3 may be superior to SAPS2 in outcome prediction in cardiac surgery patients. Design. All consecutive patients undergoing cardiac surgery between January 2007 and December 2010 were included in our prospective study. Both models were tested with calibration and discrimination statistics. We compared the AUC of the ROC curves by DeLong's method and calculated OCC values. Results. A total of 5207 patients with mean age of 67.2 ± 10.9 years were admitted to the ICU. The mean length of ICU stay was 4.6 ± 7.0 days and the ICU mortality was 5.9%. The two tested models had acceptable discriminatory power (AUC: SAPS2: 0.777–0.875; SAPS3: 0.757–893). SAPS3 had a low AUC and poor calibration on admission day. SAPS2 had poor calibration on Days 1–6 and 8. Conclusions. Despite including cardiac surgery patients, SAPS3 was not superior to SAPS2 in our analysis. In this large cohort of ICU cardiac surgery patients, performance of both SAPS models was generally poor. In this subset of patients, neither scoring system is recommended. 相似文献