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71.
In this study, catalase enzyme was immobilized by entrapping in alginate beads in the presence of gelatin. In the optimization studies of the bioactive layer immobilized some parameters such as enzyme amount, alginate, gelatin, and crosslinking agent glutaraldehyde amount were determined as 700 U/mL, 2.0%, 18 mg/mL, and 5.0%, respectively. Effects of pH and temperature on the immobilization were also investigated. In the characterization studies of the immobilized enzyme storage and thermal stability experiments were done. The immobilized enzyme was used for the decomposition of hydrogen peroxide in milk samples and also by using a catalase biosensor prepared by the decomposition level of hydrogen peroxide was detected.  相似文献   
72.
Inhibin is a heterodimeric protein hormone that appears to be a sensitive immunohistochemical marker of sex cord-stromal tumors. Although sex cord-stromal tumors can usually be distinguished from ovarian epithelial tumors or their metastases by morphology or by using antibodies against intermediate filaments, the diagnosis remains difficult in rare situations in such cases as sarcomatoid granulosa-theca cell tumors, ovarian small cell carcinomas, or soft-tissue sarcomas. The purposes of this study were to examine inhibin alpha and beta immunoreactivity in a wide range of gonadal stromal neoplasms and to assess its value in the differential diagnosis of problematic tumors. A total of 108 paraffin-embedded ovarian and extraovarian tumors were examined immunohistochemically by using anti-alpha inhibin and anti-beta inhibin. Inhibin alpha immunostaining was identified in 46 (81%) of 57 gonadal stromal tumors, one (14%) of seven endometrial stromal tumors, and one (50%) of two primary ovarian carcinoid tumors. Inhibin beta immunostaining was detected in 55 (96%) of 57 gonadal stromal tumors, two (29%) of seven endometrial stromal tumors, one (50%) of two dysgerminomas, and in all of two (100%) primary ovarian carcinoid tumors. Inhibin alpha expression was not detected in any ovarian surface epithelial tumor cells. Some surface epithelial tumors showed stromal inhibin alpha (15% of cases) and inhibin beta (48% of cases) positivity. Weak immunoreactivity for inhibin beta was found in most (83% of cases) ovarian surface epithelial tumors. Two ovarian Burkitt lymphomas were negative for inhibin alpha and beta. Inhibin alpha is a sensitive immunohistochemical marker of gonadal stromal tumors and is of value in the differential diagnosis of ovarian neoplasia. Inhibin beta is a nonspecific marker for ovarian neoplasms, showing expression on tumor and stromal cells of different epithelial or stromal tumors.  相似文献   
73.
OBJECTIVE: The purpose of this study is to test the association between joint hypermobility syndrome (JHS) and panic disorder (PD) and to determine whether mitral valve prolapse (MVP) modifies or accounts in part for the association. METHOD: A total of 115 subjects are included in this study in three groups. Group I (n = 42): panic disorder patients with MVP. Group II (n = 35): panic disorder patients without mitral valve prolapse. Group III (n = 38): control subjects who had mitral valve prolapse without any psychiatric illness. Beighton criteria were used to assess joint hypermobility syndrome. Two-dimensional and M-mode echocardiography was performed on each subject to detect mitral valve prolapse. RESULTS: Joint hypermobility syndrome was found in 59.5% of panic disorder patients with mitral valve prolapse, in 42.9% of patients without mitral valve prolapse and in 52.6% of control subjects. Beighton scores was 4.93 +/- 2.97 in group I, 4.09 +/- 2.33 in group II, and 4.08 +/- 2.34 in group III. There was no significant difference between groups according to Beighton scores. CONCLUSION: We did not detect a statistically significant relationship between panic disorder and joint hypermobility syndrome. Mitral valve prolapse and joint hypermobility syndrome are known to be etiologically related and we suggest that mitral valve prolapse affects the prevalence of joint hypermobility syndrome in the panic disorder patients.  相似文献   
74.
Intelligent polymers, also referred as "stimuli-responsive polymers" undergo strong property changes (in shape, surface characteristics, solubility, etc.) when only small changes in their environment (changes in temperature, pH, ionic strength light, electrical and magnetic field, etc.). They have been used in several novel applications, drug delivery systems, tissue engineering scaffolds, bioseparation, biomimetic actuators, etc. The most popular member of these type of polymers is poly(N-isopropylacrylamide) (poly(NIPA)) which exhibits temperature-sensitive character, in which the polymer chains change from water-soluble coils to water-insoluble globules in aqueous solution as temperature increases above the lower critical solution temperature (LCST) of the polymer. Copolymerization of NIPA with acrylic acid (AAc) allows the synthesis of both pH and temperature-responsive copolymers. This paper summarizes some of our related studies in which NIPA and its copolymers were synthesized and used as intelligent carriers in diverse applications.  相似文献   
75.
There are several treatment modalities for Langerhans' cell histiocytosis (LCH) of bone, formerly usually referred to as eosinophilic granuloma, including surgery, radiotherapy and chemotherapy. In spinal lesions, surgery is not recommended generally, because of the potential for reconstitution of vertebral height. We report a case of multifocal monosystemic LCH treated by surgery and chemotherapy for calvarial and spinal lesions. A 7-year-old boy was initially operated for an occipital monostotic LCH of bone. Then, he was treated by surgery for cervical and thoracic lesions, and by chemotherapy with vinblastine. The patient had no complaints at the 24-month follow-up. Although surgery is not recommended for spinal lesions in children with LCH of bone, short segmental fusion and internal fixation may be a suitable choice for selected cases, especially in children who are not likely to comply with activity restrictions and in those who it is difficult to follow up. The treatment must be planned according to the characteristics of the patient.  相似文献   
76.
OBJECTIVE(S): The accelerative effect of honey in the wound healing process is known. This effect is related to its specific physical properties of hygroscopicity, hypertonicity, lower pH and complex chemical composition. Because peritoneal healing is a kind of wound healing process we hypothesised that post-operative peritoneal adhesions (PPA) may be reduced with intra-peritoneal honey administration. STUDY DESIGN: The study was conducted with 40, 6-month-old, out-bred female Wistar albino rats with a mean weight of 197 +/- 12 g. The rats were divided into two equal groups. An adhesion model was constituted in the cecum and terminal ileum of all rats in each groups. Later the adhesion areas were washed with 0.9% NaCl solution and 5 ml of the same solution was left in the peritoneal cavity in the control group. The same area in the rats in the other group was covered with honey and 5 ml of honey was left in the peritoneal cavity of each animals. Ten days later the rats were sacrificed and the adhesions were graded according to their degree of severity. Statistical analysis was performed with the non-parametric Mann-Whitney U-test. RESULTS: In the control group, there were no rats with grade-0 or grade-1 adhesions but in the honey administered group there were six rats (30%) with grade-0 and 12 rats (60%) with grade-1 adhesions. In the control group, there were six rats (30%) with grade-2 and 14 rats (70%) with grade-3 adhesions. In the honey administered group while two rats (10%) with grade-2 adhesions were present, no rat with grade-3 adhesions was seen. In the comparison, the difference between the groups was found to be highly significant (P < 0.001). CONCLUSION(S): The wound healing accelerative effect and the mechanical barrier formed by the honey, since, it has a high density and, thus, absorbed slowly from peritoneal cavity, may be the reasons for its inhibitory effect on the PPA. This study indicates that though the mechanism is not clear intra-peritoneal honey administration reduces PPA.  相似文献   
77.
Skin metastasis from endometrial adenocarcinoma in the radiotherapy field is reported. A 60-year-old woman with FIGO stage IB, grade 2 endometrial adenocarcinoma presented 24 months after initial surgery with skin metastasis located on the abdomen.  相似文献   
78.
Taking pictures of microstructures is difficult, requiring sophisticated cameras coupled by the microscopes. Furthermore, it may not be feasible to find an operating microscope paired with a camera, especially in laboratory conditions. Considering the difficulty of obtaining microscopic photographs in clinical and laboratory settings, this report describes a practical method of digital photography of microstructures using a consumer-type digital camera. The technique can be summarized simply as placing the lens of a consumer-type digital camera over the eyepieces of a surgical microscope, whereby the anatomic structure of interest is focused. The image thus obtained is transferred to the computer, using easily available software programs. The authors conclude that this method is an inexpensive and practical way of capturing photographs of microstructures, obviating the need for using microscopes coupled by the cameras.  相似文献   
79.
The pathogenesis of clubfoot is unknown despite numerous hypotheses. To clarify the relationship between the plasma total homocysteine level and congenital idiopathic clubfoot, blood samples from mothers of children with congenital idiopathic clubfoot (group 1) and mothers of children without congenital anomaly (group 2) were studied. Groups were the same for factors affecting the plasma total homocysteine level. Mean plasma total homocysteine level was 16.34+/-4.78 micromol/L in group 1 and 11.02+/-1.85 micromol/L in group 2, and there was significant statistical difference between the groups (P<0.05). Congenital idiopathic clubfoot showed a significant association with high plasma total homocysteine level. This study may be a step toward clarification of clubfoot pathogenesis.  相似文献   
80.
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