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21.
Ritscher-Schinzel syndrome, also known as the 3C syndrome, is a rare, autosomal recessive syndrome characterized by craniofacial, cerebellar, and cardiac anomalies. Cardiac manifestations include ventricular septal defect, atrial septal defect, tetralogy of Fallot, double outlet right ventricle, hypoplastic left heart, aortic stenosis, pulmonic stenosis and other valvular anomalies. Central nervous system anomalies include Dandy-Walker malformation, cerebellar vermis hypoplasia and enlargement of the cisterna magna. Craniofacial abnormalities seen are cleft palate, ocular coloboma, prominent occiput, low-set ears, hypertelorism, down-slanting palpebral fissures, depressed nasal bridge and micrognathia. Dandy-Walker malformation, posterior fossa cyst, hydrocephalus and congenital heart defect are common malformations that may occur in isolation or as a part of many syndromes. Accurate genetic diagnosis and counseling require detailed analysis of the external as well as the internal anatomy and knowledge of the relative frequencies of various malformations in syndromes that may have overlapping clinical signs. We have had the opportunity recently to study four cases of the Ritscher-Schinzel syndrome. A review of all reported cases is presented and an attempt made to define the minimum diagnostic criteria for the Ritscher-Schinzel syndrome. Of the nine craniofacial anomalies commonly reported as a part of the Ritscher-Schinzel syndrome, we consider two i.e., cleft palate and ocular coloboma, to be readily and objectively ascertainable. The other seven craniofacial traits, however, are somewhat subjective, require expert interpretation and are sometimes difficult to ascertain in a newborn or stillborn fetus. These are prominent forehead, prominent occiput, hypertelorism, down-slanting palpebral fissures, low-set ears, depressed nasal bridge and micrognathia. At least four of these were present in all cases that had a secure diagnosis of the Ritscher-Schinzel syndrome. Thus, the criteria we propose to establish the diagnosis of the Ritscher-Schinzel syndrome in a chromosomally normal sporadic case are the presence of cardiac malformation other than isolated patent ductus arteriosus, cerebellar malformation, and cleft palate or ocular coloboma or four of the following seven findings: prominent forehead, prominent occiput, hypertelorism, down-slanting palpebral fissures, low-set ears, depressed nasal bridge, and micrognathia.  相似文献   
22.
The Rotalex test, a commercial latex agglutination test for rotavirus, was compared with direct electron microscopy (EM) and the Rotazyme test I, a commercial enzyme immunoassay, for detection of rotavirus in stools of children and neonates. For initial stool specimens from 265 children (less than 3 years old) with diarrhea, the Rotalex test had a sensitivity of 81.7% and specificity of 99.5% compared with EM results. Positive and negative predictive values were 98 and 94.9%, respectively. The Rotalex test was slightly more sensitive and specific than the Rotazyme test. When daily stool specimens from patients with rotavirus gastroenteritis were examined, the sensitivity of the Rotalex test varied depending on the time of stool collection relative to the onset of symptoms. Sensitivity was 100 (20/20), 96 (23/24), and 54% (7/13) during 1 to 4, 5 to 7, and 8 to 18 days, respectively, after the onset of symptoms. The sensitivity of the Rotazyme test varied similarly with days from onset. We also examined 214 EM-negative stool specimens from asymptomatic newborns. False positivity by the Rotalex test was only 3.3% (7/214) compared with 4.2% (9/215) for the Rotazyme test. The Rotalex test was as sensitive and specific as EM for detection of rotavirus during the acute stage of illness and much faster and cheaper than EM or the Rotazyme test. The test appears to be suitable for routine use in small hospitals, emergency wards, or even the physician's office for rapid diagnosis of rotavirus gastroenteritis.  相似文献   
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BackgroundPersistent wound drainage after total joint arthroplasty (TJA) increases the risk of surgical site infections (SSIs). Closed incision negative pressure wound therapy (ciNPWT) decreases infections in traumatic wounds, but evidence for its use after elective TJA is limited. The purpose of this meta-analysis of level I studies is to determine the effect of ciNPWT on risk of SSI and wound complications following TJA.MethodsMEDLINE, EMBASE, CINAHL, and Cochrane Library were searched for randomized controlled trials comparing ciNPWT vs standard dressings after total hip (THA) and total knee arthroplasty (TKA). Studies exclusively involving THA for femoral neck fractures were excluded. Risk of SSI and noninfectious wound complications (blisters, seroma, hematoma, persistent drainage, dehiscence, and wound edge necrosis) following TJA were analyzed.ResultsSSI risk was lower with ciNPWT compared to standard dressings (3.4% vs 7%; relative risk [RR] 0.48, P = .007), specifically in revision THA and TKA (4.1% vs 10.5%; RR 0.41, P = .03). ciNPWT increased the noninfectious complication risk after primary TKA (RR 4.71, P < .0001), especially causing wound blistering (RR 12.66, P < .0001). ciNPWT decreased hospital length of stay by 0.73 days (P = .04) and reoperation rate (RR 0.28, P = .01).ConclusionciNPWT decreases SSI risk compared to standard dressings after revision TJA, but not primary TJA. ciNPWT is associated with >12-fold increased risk of wound blistering after primary TKA. ciNPWT plays a role in revision TJA management, but additional randomized controlled trials with uniform wound assessment methods must be performed to sufficiently power findings and draw conclusions on the use of ciNPWT after primary TJA.  相似文献   
25.
IntroductionLatarjet procedure is commonly performed for recurrent anterior shoulder instability with glenoid side bone loss. Classic Latarjet procedure can be performed using specially designed drill guides, jigs, or by freehand technique. Here we have described a technical note on classic Latarjet procedure performed with freehand technique utilizing simple rulers and caliper. The functional and radiological outcomes of our patients have also been analysed.Material and Methods149 open classic Latarjet procedures were performed using our technique between March 2015 and July 2018. The mean age of the patients was 32.95 years (Range 22–59 years). The functional outcome of the patients was measured using Western Ontario Shoulder Instability (WOSI) and Oxford Shoulder Instability Score (OSIS) at 2 years of follow-up. Screw and graft positioning were studied in 24 consecutive patients with a postoperative computed tomography (CT) scan.ResultsThere was no incidence of recurrent subluxation or dislocation post-surgery. Mean OSIS score increased from 15.63 ± 3.20 preoperatively to 42.44 ± 3.88 postoperatively (p value < 0.05). WOSI score decreased significantly from 62.54% ± 8.24 to 10.26 ± 6.33 postoperatively at 2-year follow-up (p value < 0.05). Postoperative CT scan also showed satisfactory screw placement in all patients.ConclusionOpen Latarjet procedure performed using freehand technique provides good functional and radiological outcomes in patients with recurrent anterior shoulder instability with glenoid side bone loss.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43465-021-00385-7.  相似文献   
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SCH 42354, a neutral metalloendopeptidase (NEP) inhibitor, is the pharmacologically active form of the prodrug SCH 42495. It exerts antihypertensive effects by potentiating atrial natriuretic peptide (ANP) activity through inhibition of its hydrolysis by NEP. The objective of this study was to characterize the pharmacokinetics (PK) and pharmacodynamics (PD) of SCH 42354 in hypertensive males. SCH 42495 12.5 to 400 mg was administered orally to hypertensive men twice daily in a double-blind, placebo controlled multiple-dose parallel group design. Plasma SCH 42354 concentration and diastolic blood pressure (DBP) data were used to develop a PK-PD model using two approaches. In the first (non-integrated) approach, the link model was used to predict effect-site concentrations, and was applied to data obtained at the 300 and 400 mg BID doses only; data at the other (lower) doses were not amenable to modeling because of high variability. Effect-site concentration and DBP data were then fit to a sigmoid Emax PD model. For the 300 mg BID dose, PD parameters were: maximum effect (Emax), 8.1mmHg; no-drug effect (Eo), 3.6 mmHg; concentration corresponding to 50% of maximum response (EC50), 0.87 g·ml–1; and gamma, 3.9. In the second (time-integrated) approach, plasma SCH 42354 concentration and effect data obtained over the entire dose range were integrated with respect to time. Average plasma concentration and DBP data were then fit to a simple Emax PD model. PD parameters obtained over the dose range were: Emax, 10.3 mmHg; Eo, 2.0 mmHg; and EC50, 0.7 g·ml–1. These were similar to the estimates obtained from the first approach, demonstrating that the integrated (average) data allow PK-PD modeling over the (entire) dose range. The analysis showed that, at steady-state, a 400 mg BID dose of SCH 42495 produced an approximate 10 mmHg decrease in DBP in hypertensive males; the average plasma SCH 42354 concentration attained at this dose was approximately 1.8 g·ml–1.  相似文献   
28.
Cytomegalovirus infection of the colon is a late and severe complication in human immunodeficiency virus patients. Despite availability of medical treatment, occasional life-saving emergency surgery must be performed. The controversial surgical aspects of treatment are discussed based upon an unusual case of aseptic generalized peritonitis without perforation. The feasibility and value of limited resection are emphasized.  相似文献   
29.
Pai RR  D'sa B  Raghuveer CV  Kamath A 《Spine》1999,24(8):739-741
STUDY DESIGN: Seventy-five surgically excised prolapsed intervertebral discs were histopathologically evaluated. Fifteen prospective normal cadaveric discs were used as control specimens. OBJECTIVE: To compare the morphologic features between the prolapsed and normal discs. SUMMARY OF BACKGROUND DATA: The histologic criteria were edge neovascularization of the fibrocartilage, chondrocyte cloning, fibrillation with fraying, and granular change. METHODS: Sections stained with hematoxylin and eosin, Van Gieson's, and toluidine blue were studied. The presence or absence of edge neovascularization was noted. The other criteria were graded based on a semiquantitative scoring system. RESULTS: Edge neovascularization was observed in 56% of the discs in the test group and in none of the control specimens. Fibrillation with fraying was the most significant finding in the test group (P < 0.001). Although the mean grades were higher in the test group, they did not predict the presence of edge neovascularization. CONCLUSIONS: Edge neovascularization was the most significant finding to confirm disc prolapse. Fibrillation with fraying, was observed more frequently in prolapsed intervertebral discs and the grades of fibrillation with fraying, chondrocyte cloning, and granular change were significantly higher in the test group. Pathologists can usually agree on the presence or absence of a particular histologic characteristic but are rarely consistent when they estimate the degree. Simple, reproducible agreed-on criteria are needed before semiquantitative evaluations become reliable.  相似文献   
30.
Accurate determination of left ventricular (LV) volume has important therapeutic and prognostic implications in patients with cardiac disease. Volume estimations by two-dimensional techniques are not very accurate due to geometric assumptions. OBJECTIVES: To validate LV volume determinations by a new transesophageal three-dimensional echocardiographic technique. We performed three-dimensional reconstruction of the LV using an echo-computed tomographic (CT) technique based on serial pullback parallel slice imaging technique in both in vitro and in vivo settings. Fourteen latex balloons with various sizes (30-235 mL) and shapes (conical, pear shaped, round, elliptical, and aneurysms in various locations) filled with known volumes of water were imaged in a water bath. From the static three-dimensional image, the LV long axis was defined and the LV was sectioned perpendicular to this axis into 2-mm slices. The volume of each slice was calculated with the observer blinded to the actual volume as the product of the slice thickness and the manually traced perimeter of the slice and the LV volume as the sum of the volumes of the slices (Simpson's method). The calculated LV volume closely correlated with the actual volume (r = 0.99, P < 0.0001, calculated volume = 1.06x - 11.3, Deltavolume = -5.7 +/- 10.0 cc). Using the same system, transesophageal echocardiographic (TEE) images of the LV were obtained in 15 patients gated to respiration and ECG. Satisfactory dynamic three-dimensional reconstruction of the LV was possible in ten patients. The three-dimensional LV volumes (systolic and diastolic) using Simpson's method correlated well with those obtained from biplane or multiplane TEE images using the area length method (r = 0.89, p < 0.0001, y = 12.7 + 0.84x, Deltavolume = 1.3 +/- 18.1 cc). The LV major-axis diameters by the two methods showed very close correlations as well (r = 0.86, P < 0.0001, y = 19 + 0.74x, Deltadiameter = 1.0 +/- 7.2 mm). We conclude that three-dimensional LV volume calculation by the echo-CT technique is intrinsically sound, is independent of LV geometry, and with some limitations, is applicable in vivo. (ECHOCARDIOGRAPHY, Volume 13, November 1996)  相似文献   
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