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1.
The risk of ventriculostomy-related hemorrhage among patients requiring antiplatelet therapy (AT) for the endovascular treatment of acutely ruptured intracranial aneurysms needed further investigation. The authors performed a systematic review and meta-analysis of the literature examining the EVD-related hemorrhage rate among patients with and without AT (controls). According to PRISMA guidelines, a comprehensive review of studies published between January 1990 and April 2018 was carried out. The authors identified series with > 5 patients reporting the EVD-associated hemorrhage rate among the AT group and the control group. Variables influencing outcomes were analyzed using a random-effects meta-analysis model. We included 13 studies evaluating 516 (with AT) and 647 (without AT) patients requiring ventriculostomy. EVD-related hemorrhage rates were higher among the AT group (125/516 = 20.9%, 95% CI = 11.9–30%, I2 = 90% vs 57/647 = 9%, 95% CI = 5.5–12.5%, I2 = 45.8%) (p < 0.0001). Major EVD-associated hemorrhage rates were low in both the AT and control group (25/480 = 4.4%, 95% CI = 1.7–7.7%, I2 = 53.9% vs 6/647 = 0.7%, 95% CI = 0.03–1.7%, I2 = 0%) (p < 0.0001). Ventriculostomy before embolization and intraprocedural AT were associated with lower rates of EVD-related bleeding (32/230 = 9.6%, 95% CI = 2.1–17.1%, I2 = 75.4% vs 6/24 = 25.1%, 95% CI = 8.8–41%, I2 = 0%) (p < 0.02). The rate of major hemorrhage was higher after dual AT (CP + ASA) compared to single AT (ASA or CP) used as an intraprocedural loading dose (13/173 = 7%, 95% CI = 3.3–10.7%, I2 = 0% vs 6/210 = 1.7%, 95% CI = 0.1–3.4%, I2 = 0%) (p < 0.009). AT during endovascular treatment of acutely ruptured intracranial aneurysms increases the risk of EVD-related hemorrhages, although most of them are small and asymptomatic. When ventriculostomy is performed before endovascular procedures requiring antiplatelet administration, the hemorrhagic risk is minimized. A single antiplatelet therapy is associated with a lower rate of major bleeding than a dual therapy.  相似文献   
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The objective was to compare the frictional forces generated by new nonconventional passive elastomeric ligatures (NCL) and conventional elastomeric ligatures (CL) under dry conditions. An experimental model reproducing the right buccal segment of the upper arch and consisting of five stainless steel 0.022-inch preadjusted brackets (from the second premolar through the central incisor) was used to assess both static and kinetic frictional forces produced by NCL and CL. The frictional forces generated by the 0.019 x 0.025-inch stainless steel wire with the two types of elastomeric ligatures were recorded by sliding the wire into the aligned brackets. The friction produced by the 0.014-inch superelastic nickel titanium wire was evaluated both in the presence of aligned brackets and of three-mm misaligned canine bracket. The amount of both static and kinetic frictions were minimal (<10 g) in the NCL group in the presence of aligned brackets with both types of wires, whereas it ranged from a minimum of 95.6 g for the 0.014-inch superelastic nickel titanium wire to a maximum of 590.7 g for the 0.019 x 0.025-inch stainless steel wire when using CL. The amount of both static and kinetic frictions in the presence of a misaligned canine bracket in the NCL group were less than half of that shown by the CL group. A recently developed passive ligature system is able to produce significantly lower levels of frictional forces in vitro when compared with conventional elastomeric modules.  相似文献   
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The current study was undertaken to evaluate both maxillary and mandibular shape/size changes in children with Class III malocclusions, treated with a functional appliance (removable mandibular retractor). Nonconventional cephalometric methods (Bookstein's shape coordinate analysis, centroid size analysis, and tensor analysis) were applied to a maxillary triangle (T-FMN-A) and to a mandibular triangle (Co-Go-Pg). A group of 30 children with treated Class III malocclusions were compared with a matched group of 30 children with untreated Class III malocclusions. Treatment with the functional appliance produced a significantly increased growth of the maxilla, featuring a more downward and forward displacement of the region of point A and a significantly more upward and forward direction of condylar growth, leading to a “shrinkage” of total mandibular length. The biologic significance of some conventional cephalometric measurements used for the assessment of both maxillary and mandibular position and structure was tested.(Am J Orthod Dentofac Orthop 1997;112:622-33.)  相似文献   
5.
The introduction of microsurgical principles in endodontic surgery involving techniques used for the preparation of root-end cavities brought about an investigation for ways of improving the visualization of the surgical field. The surgical microscope can be used in combination with the endoscope to enhance visibility during periradicular surgery. In this presentation, the authors highlight the application and analysis of these two magnification devices during endodontic microsurgery.  相似文献   
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Summary The clinical records of 103 Italian patients with inherited thrombophilia and thrombosis were reviewed to estimate the incidence of thrombotic recurrences and major bleeding complications according to the different duration of oral anticoagulant prophylaxis (OAP). The incidence of the first thrombotic recurrence was 2.9, 7.4 and 10.8×100 patients/year, respectively, in subjects receiving lifelong OAP, stopping OAP after a mean of 9 months (range 1–30 months) or not receiving OAP. The probability to remain free from thrombotic recurrences in patients undergoing lifelong OAP, as estimated by the Kaplan-Meier method, was significantly higher in comparison with untreated patients (p<0.001), but did not reach the statistical significance in comparison with patients who stopped prophylaxis. The incidence of further thrombotic recurrences was 1.2, 21.1 and 22.3×100 patients/year, respectively, in the three groups defined above. The difference between patients who prolonged indefinitely OAPvs those who stopped or did not receive OAP was statistically significant (p=0.003). Two intracranial bleedings, one of which fatal, were observed in patients undergoing lifelong OAP, whereas no major bleeding complications occurred in the other two groups. Our study supports the recommendations to continue indefinitely OAP in patients with inherited thrombophilia and recurrent thrombosis, but suggests caution in starting lifelong prophylaxis soon after the first thrombotic event in all patients. Members of the Study Group: F. Baudo (Milano); M. Berrettini (Perugia); G. Castaman (Vicenza); N. Ciavarella (Bari); S. Coccheri (Bologna); V. De Stefano (Roma); A. G. Dettori (Parma); N. Erba (Merate); G. Leone (Roma); P. M. Mannucci (Milano); C. Manotti (Parma); M. G. Mazzucconi (Roma); G. Palareti (Bologna); F. Panicucci (Pisa); E. Pogliani (Monza); F. Rodeghiero (Vicenza); A. Tripodi (Milano).  相似文献   
8.
Cutaneous ulceration is a difficult medical problem and a major source of morbidity for patients. In the surgical treatment of ulcers, debridement is the first step, and it can be carried out using several surgical tools. Recently, new surgical devices have emerged using plasma‐mediated electrical discharges with a lower peak temperature. A prospective single‐blind trial was conducted on chronic ulcers not responsive to common non‐surgical management. Patients were randomly separated into 2 groups: Group A received surgical debridement with conventional electrocautery, and Group B received surgical debridement using the plasma‐mediated device. Histological samples were collected intraoperatively to evaluate the thermal damage during the surgical procedure and 2 weeks after surgery to evaluate the inflammatory response and collagen deposition. The width of coagulation necrosis at the incision margins in Group B was significantly shorter compared with Group A (P = .001). The inflammatory cell infiltration showed a cellular distribution percentage that was quite equal between the 2 groups. The granulation tissue showed an abundant deposition of dense and mature collagen in Group B, compared with Group A, where the mature collagen appeared in small quantities (P < .001). Microbial culture showed a lower incidence of postoperative infections in Group B compared with the control group (P < .05). The study demonstrated, based on the results, that the new technology with the use of a lower temperature electrosurgical device represents an effective therapeutic weapon for the surgical treatment of skin ulcers, both vascular and extravascular types.  相似文献   
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Left atrial appendage (LAA) closure prevents thromboembolic risk and avoids lifelong anticoagulation due to atrial fibrillation (AF). Nowadays, AtriClip, a modern epicardial device approved in June 2010, allows external and safe closure of LAA in patients undergoing cardiac surgery during other open‐chest cardiac surgical procedures. Such a surgical approach and its epicardial deployment differentiates LAA closure with AtriClip from percutaneous closure techniques such as Watchman (Boston Scientific, Marlborough, MA, USA), Lariat (SentreHEART Inc., Redwood City, CA, USA), and Amplatzer Amulet (St. Jude Medical, St. Paul, MN, USA) device procedures. AtriClip positioning must consider perioperative transesophageal echocardiography (TEE) to confirm LAA anatomical features, to explore the links with neighboring structures, and finally to assess its successful closure. We report a sequence of images to document the role of intraoperative TEE during an elective aortic valve replacement and LAA external closure with AtriClip.  相似文献   
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