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31.
PURPOSE: We report preliminary results of a multicenter study of the Italian Society of Video Surgery in Infancy on the laparoscopic treatment of pediatric varicocele. MATERIALS AND METHODS: A total of 161 children 6 to 16 years old (median age 12.5) underwent laparoscopic treatment of varicocele at 6 pediatric surgery divisions. Varicocele was on the left side in 159 cases (98.7%) and bilateral in 2 (1.3%). Two boys had recurrent left varicocele. All children were treated with laparoscopy, including ligation of the spermatic veins only in 28 (17.3%), and ligation of the testicular veins and artery in 133 (82.7%). In 10 boys (6.2%) an additional procedure was done simultaneously, including closure of an apparently patent peritoneal vaginal duct on the right side in 7 and resection of epiploic adhesions between the intestinal loops and abdominal wall from previous appendectomy in the remaining 3. RESULTS: Average operative time was 30 minutes and hospitalization was about 24 hours. At followup there were 13 minor complications (8%), including left hydrocele in 9 children who underwent the Palomo technique, minor scrotal emphysema in 2 and umbilical granuloma in 2. In our series varicocele recurred in 1 boy (3.5%) who underwent ligation of the spermatic veins only and in 3 (2.2%) treated with the Palomo technique. CONCLUSIONS: Our preliminary experience shows that the results of the laparoscopic approach are comparable to those of the open approach. However, the important advantages of laparoscopy over the open approach are its minimal invasiveness and precision of intervention. Moreover, laparoscopy allows treatment of other intra-abdominal pathological conditions using the same anesthesia, as in 10 patients in our series. We believe that ligating the testicular veins and artery is preferable to ligating the testicular veins only, even if the incidence of hydrocele is not negligible after the Palomo procedure.  相似文献   
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The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure–EEM relationships and kinetics revealed that the components extracted from EEM–PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM–PARAFAC methodology.

Drug quality and assurance changes with time under the influence of a variety of environmental factors, such as light, temperature, and moisture.  相似文献   
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Herpes Simplex Virus type 1 (HSV‐1) is a very common infection often localized in the mucocutaneous junction of the lip. Rarely, it could be detected also in periodontal tissues, associated with an elevated risk of periodontal disease progression and gingival recessions. Recently, HSV‐1 and numerous co‐infections have been reported in literature associated with the Coronavirus and subsequent COVID‐19 disease. This report illustrates a case of HSV‐1 in a patient with Covid‐19 infection, showing the presence of ulcers and vesicles on the gingival margin of maxillary teeth associated with soreness and pain. The histology highlighted the presence of intraepithelial cell ballooning, confirming the diagnosis of HSV‐1 infection.  相似文献   
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1. No demonstrable antiopsonins are formed in rabbits following the intravenous injection of monovalent pneumococcus horse sera, Types I, II, and III. 2. The serum of rabbits injected with immune pneumococcus horse serum, Type I, II, or III, or with normal horse serum, when mixed in the proportion of 1:4 with Type I or Type II pneumococcus horse serum, can greatly augment, in vitro, the opsonization and agglutination of Type I and Type II pneumococci by the homologous immune horse sera. No similar effect is obtained with Type III serum and pneumococci. 3. The increase in opsonization and agglutination is dependent upon (a) specific sensitization of the pneumococci by the homologous immune serum and (b) the presence of the precipitating serum. In the absence of sensitization, as when a heterologous or normal horse serum is employed, opsonization and agglutination do not occur, even though a precipitating mixture is provided. The substitution of normal rabbit serum for the precipitating rabbit serum gives opsonization and agglutination in dilutions slightly higher than are effected with salt solution only, due possibly to the more favorable medium created for the leucocytes by the addition of 25 per cent of whole rabbit serum. 4. Different methods of combining the immune horse serum, precipitating rabbit serum, and pneumococci yield very similar results, preliminary sensitization of the bacteria before precipitation, or precipitation in the rabbit-horse serum mixture before the addition of the pneumococci for sensitization causing little if any difference in result from that obtained when immune horse serum, precipitating rabbit serum, and pneumococci are all mixed and incubated together. 5. This increased opsonization in the test-tube does not seem to be paralleled by increased protective power, or at any rate such protection is not readily demonstrated.  相似文献   
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Assessing maximum voluntary bite force is important to characterize the functional state of the masticatory system. Due to several factors affecting the estimation of the maximum bite force, a unique solution combining desirable features such as reliability, accuracy, precision, usability, and comfort is not available. The aim of the present study was to develop a low-cost bite force measurement device allowing for subject-specific customization, comfortable bite force expression, and reliable force estimation over time. The device was realized using an inexpensive load cell, two 3D printed ergonomic forks hosting reusable subject-specific silicone molds, a read-out system based on a low-cost microcontroller, and a wireless link to a personal computer. A simple model was used to estimate bite force taking into account individual morphology and device placement in the mouth. Measurement reliability, accuracy, and precision were assessed on a calibration dataset. A validation procedure on healthy participants was performed to assess the repeatability of the measurements over multiple repetitions and sessions. A 2% precision and 2% accuracy were achieved on measurements of forces in the physiological range of adult bite forces. Multiple recordings on healthy participants demonstrated good repeatability (coefficient of variation 11%) with no significant effect of repetition and session. The novel device provides an affordable and reliable solution for assessing maximum bite force that can be easily used to perform clinical evaluations in single sessions or in longitudinal studies.  相似文献   
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The incidence and characteristics of cement-asbestos pneumoconiosis were compared with those of asbestosis and cement pneumoconiosis in three homogeneous samples of cases.

The clinical, functional, and radiological features of cement-asbestos pneumoconiosis are similar to those of classical asbestosis, but the observed changes are less common and occur after a longer exposure.  相似文献   
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