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41.
Over the past 15 years, the use of β-agonists has declined worldwide. Following the Royal College of Obstetricians and Gynaecologists guidelines in 2002, clinicians in the UK and beyond were faced with the dilemma of continuing to use β-agonists, desist from using tocolytic therapy completely or choosing to change to atosiban or calcium channel blockers (CCBs). While grade A level 1 evidence exists to show that atosiban is significantly more efficacious than placebo and significantly safer than β-agonists for the treatment of spontaneous preterm labour, the evidence for CCBs, such as nifedipine, is much less robust and no placebo-controlled trials have been performed. Published studies on nifedipine are largely investigator-led studies of small sample size, which lack sufficient power. As a result, most of the evidence has been based on meta-analyses of these studies, which look retrospectively at pooled data and are only as good as the quality of the studies included. In light of this, a tool was developed to produce a systematic review of studies on tocolytic effectiveness, which can and should be applied to all tocolytics and which considered both method- and topic-specific markers of quality. In the process of applying this tool to nifedipine, an extensive literature search identified 31 studies for a systematic review of the quality of nifedipine studies assessed by eight paired reviewers with wide experience in the subject of spontaneous preterm labour and preterm birth. Forty topic- and method-specific items of quality were assessed. The paucity of good quality studies of nifedipine used for the treatment of spontaneous preterm labour should be highlighted in meta-analyses or systematic reviews, which measure efficacy and should limit and influence the degree to which recommendations and guidelines are made on the basis of such studies.  相似文献   
42.
Liver rupture and hemorrhage, are the most unusual and serious complications of HELLP syndrome (hemolysis--elevated liver enzymes--low platelet count). The management should be aggressive by treating coagulopathy and favouring a prompt delivery. Liver rupture remains a surgical emergency with control of bleeding based on trauma surgery. The aggressive approach to the management of these patients led to a remarkable decrease of mortality rates.  相似文献   
43.
Placenta accreta is a life-threatening obstetric pathology characterized by an abnormal invasion of chorionic villi into the uterine wall. The management represents a challenge for the gynecologist, especially in patients desiring to preserve their fertility. Several methods have been proposed to avoid hysterectomy. A case of a hysteroscopic conservative management with the cold loop technique in a puerpera with a large mass of placenta accreta residuals is described. The chorionic tissue was safely detached and it was subsequently removed by an electric cutting loop. Even in the absence of a clear cleavage plane, the thermal damage of surrounding healthy myometrium and dreadful complications as uterine perforation due to the electric cutting loop were avoided. The cold-loop hysteroscopic resection seems to be a safe and effective choice for the treatment of retained placenta accreta in patients desiring to preserve fertility. Moreover, it can also be proposed to patients who need to be treated immediately after delivery.  相似文献   
44.
Summary The pharmacokinetics, hypotensive effect and tolerability of a new vasodilator, tolmesoxide (T), have been studied in 6 uncontrolled hypertensive patients receiving atenolol and a diuretic. After a 50 mg oral dose mean (± SD) peak plasma concentration of T was 1.13±0.29 µg/ml–1 and occurred 0.79±0.40 h after the dose; mean peak plasma concentration of its sulphone metabolite (M) was 0.37±0.09 µg/ml–1 at 1.92±1.32 h after the dose. Following peak plasma concentrations there was a monoexponential decline in T and M concentrations with half-lives of 2.78±0.77 h and 10.78±7.85 h respectively. There was a linear increase in plasma concentration of T and M during incremental dosing with 50–200 mg t. i. d. During in-patient administration of 600–900 mg T daily (n=6) there was no significant change in blood pressure, pulse rate or body weight. Out-patient administration of 900 mg T daily (n=4) was associated with a significant fall in mean systolic but not diastolic bp (lying –15/+1 mm Hg. standing –25/–8 mm Hg). A further fall was observed in 2 subjects receiving 1200 mg and 1500 mg daily. Supine pulse rate increased (mean ± SD) significantly from 55±5/min to 66±8/min following 900–1500 mg T in 4 out-patients. Severe nausea and other gastro-intestinal side-effects in all subjects receiving 600–900 mg daily eventually necessitated drug withdrawal. In its present from T is not recommended for the treatment of hypertension.  相似文献   
45.
Harmful algal blooms (HABs) are naturally occurring phenomena, and cyanobacteria are the most commonly occurring HABs in freshwater systems. Cyanobacteria HABs (cyanoHABs) negatively affect ecosystems and drinking water resources through the production of potent toxins. Furthermore, the frequency, duration, and distribution of cyanoHABs are increasing, and conditions that favor cyanobacteria growth are predicted to increase in the coming years. Current methods for mitigating cyanoHABs are generally short-lived and resource-intensive, and have negative impacts on non-target species. Cyanophages (viruses that specifically target cyanobacteria) have the potential to provide a highly specific control strategy with minimal impacts on non-target species and propagation in the environment. A detailed review (primarily up to 2020) of cyanophage lifecycle, diversity, and factors influencing infectivity is provided in this paper, along with a discussion of cyanophage and host cyanobacteria relationships for seven prominent cyanoHAB-forming genera in North America, including: Synechococcus, Microcystis, Dolichospermum, Aphanizomenon, Cylindrospermopsis, Planktothrix, and Lyngbya. Lastly, factors affecting the potential application of cyanophages as a cyanoHAB control strategy are discussed, including efficacy considerations, optimization, and scalability for large-scale applications.  相似文献   
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48.
Tissue temperature distribution plays a crucial role in the outcome of laser-induced thermotherapy (LITT), a technique employed for neoplasias removal. Since recent studies proposed LITT for pancreatic tumors treatment, assessment of temperature and of its effects around the laser applicator could be useful to define optimal laser settings. The aims of this work are temperature monitoring and measurement of ablated tissue volume in an ex vivo porcine pancreas undergoing double-applicator LITT. A three-dimensional numerical model is implemented to predict temperature rise and volumes of ablated tissue in treated pancreas. Experiments are performed to validate the model, with two modalities: (1) 12-fiber Bragg grating sensors are adopted to monitor the heating and cooling during LITT at several distances from the applicators tip, and (2) 1.5-T MR imaging is used to estimate the ablated volume. Experimental data agree with theoretical ones: at 2 mm from both applicators tips, the maximum temperature increase is approximately 60 °C downward from the tips, while it increases of about 40 °C and 30 °C, respectively, at the level and upward from the tips. This behavior occurs also at other distances, proving that the tissue downward from the tip is mostly heated. Furthermore, the estimated volume with MRI agrees with theoretical one (i.d., 0.91?±?0.09 vs. 0.95 cm3). The encouraging results indicate that the model could be a suitable tool to choose the optimal laser settings, in order to control the volume of ablated tissue.  相似文献   
49.
Petrequin  PR; Todd  RF d; Smolen  JE; Boxer  LA 《Blood》1986,67(4):1119-1125
The widespread assumption that cytoplasts generated from human polymorphonuclear leukocytes (PMNs) are vesicles consisting solely of cytoplasm surrounded by plasma membrane and devoid of granule activity remains to be tested. PMN cytoplasts were prepared by centrifugation of intact cells on a Ficoll step gradient in the presence of cytochalasin B. Two granule membrane markers, Mol, a fluorometrically detectable antigen, and cytochrome b, both of which have been shown to translocate to the plasma membrane during granule release, were compared for their activity in cytoplasts and intact PMNs. We found that the amount of Mol detected on the plasma membrane of intact PMNs, as compared with other membrane markers (such as antigens LFA-1 and beta 2m), increased 1.6- fold upon exposure of PMNs to Ficoll plus cytochalasin B prior to centrifugation. Another twofold increase in Mol expression occurred upon cytoplast preparation. Release of the granule enzymes, vitamin B12- binding protein, and lysozyme were also followed and correlated well (r = .78 and .92) with the amount of Mol antigen present on the cell surface. Cytochrome b was also found to be higher (1.4-fold) on plasma membranes isolated from cytoplasts than on plasma membranes isolated from intact control cells. These results indicate that some fusion of granule membranes and plasma membranes occurred during treatment of PMNs with Ficoll plus cytochalasin b and during cytoplast preparation.  相似文献   
50.
Objective: The aim of the CAMPO-RHE study was to determine the incidence of rheumatoid arthritis (RA), psoriatic arthritis (PsA) and polymyalgia rheumatica (PMR) in patients attending a rheumatologic outpatient’s clinic of a new institution in Campobasso, Italy.

Methods: Campobasso is a small town of approximately 50,000 inhabitants located in the inland territory of central Italy (Molise), and Public Health is managed from a single health authority. In Italy, all citizens are registered with a National Health System of General Practitioner (GP) Physicians. Between the 1st of June 2014 and the 31st of May 2016, all consecutive adult patients, sent by a GP, of Campobasso with any diagnosis of musculoskeletal symptoms/signs/complaints were evaluated in a single rheumatology outpatient clinic of our Academic Unit. The clinic represents the first and unique reference for GPs about rheumatic diseases in the territory. Subjects were classified using the 2010 EULAR criteria for RA, the CASPAR criteria for PsA and the 2012 ACR classification criteria for PMR.

Results: 1003 adult patients, sent by GPs, with articular or musculoskeletal complaints visited our clinic. Of these, 409 inhabitants of the municipality of Campobasso were evaluated for the study. During the 2-year study period we diagnosed 18, 19 and 12 new cases of RA, PsA and PMR respectively, with a new incident cases rate of 21.4, 22.59 and 27.43/100,000/year on the population at risk.

Conclusion: The results of our study could contribute to better define the incidence of these rheumatic diseases classified with the new classification criteria.  相似文献   

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