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1.
Purpose. The interaction of salmon calcitonin (sCT) and poly (d,l-lactide-co-glycolide) was detected during preparation and evaluation of microspheres. The purpose of this study was to quantitate the extent and nature of the interaction. Methods. Blank microspheres were prepared by an aqueous emulsification solvent extraction technique. Adsorption studies were carried out at six concentrations of sCT and three concentrations of microspheres. Adsorption isotherms were constructed using the Langmuir and Freundlich treatments. Results. Adsorption at 1 mg/ml sCT concentration resulted in almost complete depletion of the peptide from the adsorption medium with the time to reach maximum adsorption decreasing with increasing microsphere concentration. At sCT concentrations below 100 µg/ml, a true equilibrium occurred in 1 hour or less while at higher concentrations (up to 350 µg/ml), a transient equilibrium was reached in 1 to 2 hours, followed by further adsorption of the peptide. The adsorption followed the Langmuir isotherm at concentrations below 200 µg/ml, indicating formation of a monolayer. Multilayer interaction, described by the Freundlich isotherm, occurred at higher concentrations and resulted in complete depletion of sCT from the adsorption medium. The affinity constant during monolayer formation was 0.09 and the plateau surface concentration was 5.1 µg/mg. The multilayer peptide-peptide adsorption showed a lower affinity (0.025) but higher capacity (24 µg/mg) than the monolayer peptide-polymer adsorption. Conclusions. The results show that poly (d,l-lactide-co-glycolide) microspheres have a high adsorption capacity for sCT which must be considered in formulating a controlled delivery product of this peptide.  相似文献   
2.
Purpose: To evaluate the effects of topical timolol and apraclonidine on retrobulbar blood flow velocity waveforms in a group of healthy volunteers.Methods: Apraclonidine 1% and timolol maleate 0.5% single dose administrations were crossed over double masked in 12 healthy volunteers. The intraocular pressure measurements were followed by Doppler examination of the ophthalmic artery and the central retinal artery.Results: Intraocular pressure was reduced significantly on both treated and fellow eyes after timolol (p = 0.003, p = 0.04 respectively) and after apraclonidine (p = 0.002, p = 0.01 respectively). After apraclonidine administration end diastolic velocity, mean velocity decreased and pulsatility index increased in the ophthalmic artery of both treated and fellow eyes. Resistivity index increased and peak systolic velocity decreased only in the ophthalmic artery of treated eyes. All Doppler indices remained nonsignificant for central retinal artery of both eyes.After timolol administration there were no significant changes of the Doppler indices in the ophthalmic artery and central retinal artery of the treated and fellow eyes.Conclusion: Topical timolol and apraclonidine significantly reduced the intraocular pressure. Single dose administration of apraclonidine 1% increased the vascular impedance distal to the ophthalmic artery. On the other hand, timolol 0.5% had no effect on vascular impedance.  相似文献   
3.
Perforation of the uterus by an intrauterine device (IUD) is a serious complication occurring at or following 1/350 to 1/2,500 insertions. It is more common among women with 'lost' IUDs. If a woman presents with pelvic pain and a history of a 'lost' IUD, X-rays of the abdomen and of the pelvis should be ordered. We report on a 'lost' IUD that had been inserted 12 years previously. It was found in the lower anterior abdominal wall. Most probably uterine perforation had happened during a dilatation and curettage (D & C) attempted for removal of the device. Thereafter the IUD must have migrated to the abdominal wall. This case illustrates that unless it can be recovered by simple traction on the threads, a trained medical professional should be called upon for removal of the IUD.  相似文献   
4.
BACKGROUND: Angiomyolipoma (AML) is a rare benign tumor that occurs most commonly in the kidney. Only a few cases have been described in the uterus. CASE: We describe a 32-year-old woman with tuberous sclerosis who presented with irregular bleeding. Preoperatively, the lesions were confused with leiomyoma on ultrasound. At laparotomy, multiple circumscribed subserosal and intramural purplish lesions on the corpus uteri were noted leading to a diagnosis of uterine angiomyolipoma with the histological and immunohistochemical findings. CONCLUSION: In contrast to other reported uterine angiomyolipoma cases, HMB-45 melanoma-specific antibody immunoreactivity is demonstrated in the present case. The histopathologic diagnosis as well as immunohistochemical analysis is discussed here with a review of the literature.  相似文献   
5.
The use of mesh in hernia repair has become common, because of lower recurrence rate and simple application. Data from the meta-analysis and the multi-central studies support the use of meshes in hernia repair. One of the complications due to the hernia repair with mesh is the infection. The incidence range is between 1 and 10%. Triclosan embedded commercial absorbable suture materials are used to reduce surgical site infection rate. This study was planned on mesh infection model, because of the low incidence rate. The agent isolated from mesh infections was mostly Staphylococcus aureus and thus it was used as the infecting agent in this research. To achieve a better therapeutic efficacy, triclosan was formulated in chitosan gels. Chitosan is an attractive biopolymer because of its biocompatible, biodegradable, bioadhesive properties. Gel formulations using chitosans (low, medium and high molecular weight) were prepared in 1% (v/v) acetic acid solution and in vitro release profiles were evaluated. Gel formulations showed release profile extended up to 7 days and high molecular weight chitosan gel formulation was released higher quantity drug than other formulations. Meshes coated with triclosan loaded chitosan gel were used to reduce bacterial count and to prevent mesh infection in the study. 24 h and simultaneous bacteria inoculation was used to model mesh infection. The rats were observed for 8 days by means of surgical site infection. On the eighth day, the animals were sacrificed and the grafts were removed. Tissue squeezers were used to liberate bacterias from removed grafts. The isolated suspensions were cultured on blood agar plates and colony-forming units were counted overnight. Grafts coated with triclosan loaded chitosan gel presented satisfactory preventive effect against graft infection.  相似文献   
6.
Pregnancy and tuberculosis (TB)  To assess TB cases during pregnancy in a developing region retrospectively and to present two case reports. Objectives  Since TB cases activated by HIV infection during pregnancy are well reported in the literature, we aimed to investigate the aggressiveness of pulmonary TB among pregnant women and to assess the effects of TB on the fetus in Kutahya, an area where HIV positive cases are not seen. Materials and methods  The medical records between 2000 and 2005 of the Provincial Health Directorate and Dispensary Against Tuberculosis in Kutahya were reviewed and analyzed retrospectively. Results  Between 2000 and 2005, 667 pulmonary TB cases were examined in the Kutahya region. Of these, 106 occurred in women at reproductive ages between 20 and 44. All were HIV negative cases. In this area, five TB cases were found during pregnancy. There were three cases seen in the first trimester, but pregnancy was ended by curettage. Two women had pulmonary TB and gave birth. Five cases were evaluated as class 1 TB. During and after pregnancy, isoniazid, rifampin, ethambutol, and pyrazinamide (INH + RFP + ETB + PRZ) were used for the treatment. Resistance to anti-TB drugs was not seen during the treatment. Neither congenial nor neonatal TB was seen. Conclusion  Generally, TB is expected to be more aggressive during pregnancy. Since our cases were HIV negative, it can be thought that TB did not progress aggressively. Less aggressiveness and non-resistance to TB treatment in HIV-negative pregnant women compared with HIV-positive women were observed. Therefore, HIV infection results in greater mortality than the triple combination of human immunodeficiency virus, mycobacterium TB, and pregnancy. Besides, the advance of TB in pregnant women was not different from that in non-pregnant women in Kutahya. The fetus and the newborn were not affected. INH, RFP, ETB, and PRZ were used for therapy.  相似文献   
7.
8.
RATIONALE AND OBJECTIVES: The authors performed this study to investigate structural variations in the trabecular bone of the proximal femur at high-resolution magnetic resonance (MR) imaging and high-resolution multisection computed tomography (CT). MATERIALS AND METHODS: Bone mineral density (BMD) was measured in 36 proximal human femur specimens by using dual x-ray absorptiometry. High-resolution MR imaging was performed at 1.5 T with an in-plane spatial resolution of 0.195 x 0.195 mm and a section thickness of 0.3 and 0.9 mm. Multisection CT was performed with an ultra-high-resolution protocol; images were obtained with an in-plane spatial resolution of 0.25 mm and a section thickness of 1 mm. In a subset of these specimens, micro CT was performed with an isotropic spatial resolution of 30 microm. Identical regions of interest (ROIs) were used to analyze images obtained with MR imaging, multisection CT, and micro CT. Trabecular bone structural parameters were obtained, and the parameters from the individual imaging modalities and BMD were correlated. RESULTS: Significant differences concerning the trabecular microarchitecture between the individual ROIs were demonstrated with multisection CT and MR imaging. A number of the correlations between structural parameters derived with multisection CT, MR imaging, micro CT, and BMD measurements were significant. For MR imaging, threshold technique and section thickness had an effect on structural parameters. CONCLUSION: Structural parameters obtained in the proximal femur with multisection CT and high-resolution MR imaging show regional differences. These techniques may be useful for depicting the trabecular architecture in the diagnosis of osteoporosis.  相似文献   
9.
OBJECTIVES: To compare WHO 1973, WHO/ISUP 1998 and WHO 1999 histologic grading systems, and also to evaluate the primary (most common) and secondary (second most common) patterns of cancer growth according to these three grading systems. MATERIAL AND METHODS: The study consisted of 87 bladder transurethral resections that were classified as grade 1, 2 and 3, and papillary urothelial neoplasm of low malignant potential (PUNLMP), low grade (LG) and high grade (HG) carcinoma considering WHO 1973 and WHO/ISUP, respectively. The WHO 1999 system was subdivided high grade into grades 2 and 3 (HG-2 and HG-3). For combined scoring, primary (most common) and secondary (second most common) grades according to extension were recorded for three grading systems. The number was repeated when only grade was seen in all extension of the tissue examined. A final combined score was obtained which ranged from 2 to 6 for the WHO 1973 and WHO/ISUP 1998 systems and from 2 to 8 for the WHO 1999 schema. The TNM system was used for the pathologic staging. RESULTS: When considering the pathological stage, there were statistical differences between the WHO 1973 grades (p=0.011 and p=0.000), and LG and HG carcinomas of WHO/ISUP 1998 (p=0.000) and also the WHO 1999 grades (p=0.010 and p=0.003), except PUNLMP. Regarding the combined scoring, significant differences were found between score 4 (2+2) and 5 (2+3) of WHO 1973 (p=0.014) and score 5 (LG+HG) and 6 (HG+HG) of WHO/ISUP 1998 (p=0.011). There was also a significant difference between scores 4 and 6, and 6 and 8 of the WHO 1999 combined scoring system (p=0.019 and p=0.019). WHO 1973, WHO/ISUP 1998 and WHO 1999 systems were positively correlated with the pathological stage (r(s)=0.30, r(s)=0.52 and r(s)=0.50, respectively), whereas there was weak association between the combined scoring systems and stage (r(s)=0.20, r(s)=0.18 and r(s)=0.19). Comparing these grading systems, the grade 2 of WHO 1973 was subdivided into LG and HG in WHO/ISUP 1998 and also LG-1and HG-2 in WHO 1999 systems. The group of HG carcinoma in WHO/ISUP 1998 which was subdivided into HG-2 and HG-3 in the WHO 1999 system was different statistically in relation to the stage. CONCLUSIONS: Our results revealed that the WHO 1999 system may be more useful to evaluate the bladder carcinoma histopathologically in comparison to the WHO 1973 and WHO/ISUP 1998 systems.  相似文献   
10.
Background  Type III supracondylar humeral fracture is a common cause of emergency hospitalization among children requiring surgical treatment. The configuration of the internal fixation material, surgical technique, and optimal timing of surgery (TS) have always been popular topics of debate. The TS in uncomplicated cases is usually determined by surgeons. Methods  In this study, we prospectively followed children with type III supracondylar fractures. We aimed to clarify the effects of injury side, gender, and post-injury delay on switching to open surgery and the ease of the reduction. Results  Based on our results, the probability of switching to open surgery increased by a factor of 4 every 5 h beginning 15 h after injury. Open surgery was necessary after 32 h. Conclusion  Reduction became technically more difficult as TS increased.  相似文献   
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