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51.
Summary The negative inotropic effect of adenosine (1–100 M) was abolished in isolated guinea-pig atria obtained from pertussis toxin-pretreated guinea pigs electrically driven at 4 Hz. However, the inhibitory effect of the same concentrations of adenosine on the cardiac response to stimulation of non-adrenergic non-cholinergic (NANC), capsaicin-sensitive sensory nerves, was not modified by the toxin.These results suggest that, while pertussis toxin-sensitive G proteins are involved in the negative inotropic effect of adenosine, they do not mediate the inhibitory effect of adenosine on cardiac NANC neurotransmission.  相似文献   
52.
A novel serum 21 kDa haptoglobin-related protein (Hpr) was investigated in patients with malignant lymphoma, to evaluate its correlation with clinical and histologic features at presentation and its possible role as a tumor marker for patient outcome. One hundred fifty eight serum samples were taken from 88 patients with non-Hodgkin’s lymphoma (n=58) and Hodgkin’s disease (n=30) at presentation and in the course of follow-up. Sera from 61 healthy volunteers served as normal controls. Serum Hpr levels in the lymphoma patients (median 430xl03 u/ml, range 0-4000xl03) were significantly higher than in the control group (median 68xl03 u/ml, range 0-180xl03) (p=0.0001). Higher median Hpr values were detected in patients with advanced disease (p=0.013), “B” symptoms (p=0.029) and in males (p=0.053). There was also a significant correlation between Hpr and erythrocyte sedimentation rate (p=0.028). Serial determinations showed a significant decrease of the initial Hpr values obtained after treatment in 41 patients, 38 of whom achieved complete remission. In the follow-up period additional Hpr measurements were taken from 17 patients. Three of them eventually relapsed, and showed increased Hpr levels at the time of relapse. Hpr levels remained low in 11 of 14 patients who maintained complete remission, and increased in three. In conclusion, serum Hpr is a new serum tumor marker of potential use in the clinical setting of lymphoma. This work is dedicated to the memory of Dr. Arie H. Bartal, a dedicated oncologist and friend. This work was supported by Chemotech Thechnologies Ltd., by grant no. 3676 from the Chief Scientist’s Office of the Ministry of Health, Israel, and by the Fund for Promotion of Research in the Technion.  相似文献   
53.
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   
54.
Background Previous experience with unacceptable adverse effects with mefloquine as treatment for uncomplicated Plasmodium falciparum malaria prompted an evaluation of the effectiveness and side effects of atovaquone–proguanil (Malarone) in a hospital setting.
Methods Atovaquone–proguanil was given as standard treatment (1,000/400mgq.d. for 3 days) to 50 adults who had traveled in Africa and returned with uncomplicated Plasmodium falciparum malaria. Half of the treated patients were African and had lived outside Africa for varying periods of time; the other half were Danish-born persons without any previous immunity towards malaria.
Results All patients treated with Malarone were cured without complications. The mean fever clearance times differed among the groups and according to various degrees of prior exposure to malaria and ranged from 1.3 to 2.2 days. Adverse effects during treatment were mild, and were likely to be due to the malaria itself. Fourteen people who had acquired falciparum malaria in spite of taking proguanil–chloroquine prophylaxis were also cured uneventfully without recrudescence.
Conclusions Malarone appears to be an effective, safe and acceptable oral treatment for uncomplicated malaria.  相似文献   
55.
56.
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   
57.
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   
58.
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   
59.
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   
60.

Background

The Pediatric Quality of Life Inventory? (PedsQL?) is a widely-used modular instrument for measuring health-related quality of life in children aged 2 to 18 years. The PedsQL? Brain Tumor Module is comprised of six scales: Cognitive Problems, Pain and Hurt, Movement and Balance, Procedural Anxiety, Nausea, and Worry. In the present study, we developed the Japanese version of the PedsQL? Brain Tumor Module and investigated its feasibility, reliability, and validity among Japanese children and their parents.

Methods

Translation equivalence and content validity were verified using the standard back-translation method and cognitive debriefing tests. Participants were recruited from 6 hospitals in Japan and the Children's Cancer Association of Japan, and questionnaires were completed by 137 children with brain tumors and 166 parents. Feasibility of the questionnaire was determined based on the amount of time required to complete the form and the percentage of missing values. Internal consistency was assessed using Cronbach's coefficient alpha. Test-retest reliability was assessed by retesting 22 children and 27 parents. Factorial validity was verified by exploratory factor analyses. Known-groups validity was described with regard to whole brain irradiation, developmental impairment, infratentorial tumors, paresis, and concurrent chemotherapy. Convergent and discriminant validity were determined using Generic Core Scales and State-Trait Anxiety Inventory for children.

Results

Internal consistency was relatively high for all scales (Cronbach's coefficient alpha > 0.70) except the Pain and Hurt scale for the child-report, and sufficient test-retest reliability was demonstrated for all scales (intraclass correlation coefficient = 0.45-0.95). Factorial validity was supported through exploratory factor analysis (factor-item correlation = 0.33-0.96 for children, 0.55-1.00 for parents). Evaluation of known-groups validity confirmed that the Cognitive Problems scale was sensitive for developmental impairment, the Movement and Balance scale for infratentorial tumors or paresis, and the Nausea scale for a patient currently undergoing chemotherapy. Convergent and discriminant validity with the PedsQL? Generic Core Scales and State-Trait Anxiety Inventory for children were acceptable.

Conclusions

The Japanese version of the PedsQL? Brain Tumor Module is suitable for assessing health-related quality of life in children with brain tumors in clinical trials and research studies.  相似文献   
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