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81.
The authors determined the intravitreal clearance of liposome-encapsulated ganciclovir. Liposome-encapsulated ganciclovir (84.1 micrograms/0.1 ml) was injected into the vitreous cavity of New Zealand rabbits, which were killed at 24 hours and 7, 14, and 28 days after injection. Total ganciclovir concentrations in the vitreous, up to 28 days, were higher than ID50 (50% inhibitory dose) for different clinical and laboratory strains of viruses belonging to the herpes simplex family.  相似文献   
82.
Morphology and function of the kidney were studied before and after percutaneous stone extraction in 33 patients with unilateral calculus disease to assess damage secondary to the extraction procedures. Anatomic changes were studied using excretory urography before the procedure and at 3 to 6 months postoperatively, and using nephrostograms and noncontrast nephrotomograms several days after the procedure. Renal function was evaluated with radionuclide renography both before surgery and at either 4 to 6 weeks or about 1 year postoperatively. Six patients had early changes detected clinically and with nephrostograms, but only three of these had abnormalities on delayed excretory urography. Significant changes in renal function were found only in those patients who had clinically detectable complications (p less than 0.05), in one case before symptoms were manifest.  相似文献   
83.
Uveal melanomas located 1 to 2 disc diameters from the disc are difficult to manage. An internal resection approach (retinochoroidectomy ab interno) for the removal of melanomas has been developed and used to remove tumors in four patients. In five additional patients this procedure was combined with external resection to remove residual suspicious tissue from the resected margins.  相似文献   
84.
We studied the toxicity of single doses of intravitreally administered alpha-interferon in albino rabbits. Doses of 420,000, 210,000, 105,000, 52,500, and 26,250 units/0.1 cc showed no significant histologic changes by light microscopy or altered retinal function assessed by photopic and scotopic electroretinography.  相似文献   
85.

Background

Besides rate and extent of weight loss, little is known regarding demographic factors predicting interval cholecystectomy (IC) after bariatric surgery and its incremental costs.

Objectives

We aim to identify risk factors predicting IC after bariatric surgery and quantify its associated costs.

Setting

Nationally representative sampling of acute care hospitals across the United States.

Methods

A retrospective cohort study was performed using the National Readmission Database 2010 to 2014. Cox proportional hazard analyses were used to identify risk factors for IC. Linear regression models were constructed to examine associations between cholecystectomy timing and cumulative hospitalization costs.

Results

An estimated national total of 553,658 patients received bariatric surgery during the study period. Of these, 3.3% received concomitant cholecystectomy (CC). After adjusting for bariatric procedure type, age, sex, complication, and length of stay, CC was independently associated with a US$1589 increase in hospitalization cost (95% confidence interval US$1021–2158, P<.01). Of patients that received no CC, only .6% underwent IC during the up to 1-year follow-up. Age<35 (P<.01), female sex (P<.01), and high preoperative body mass index (P = .03) were all risk factors for IC. IC was independently associated with a US$1499 higher cumulative hospitalization cost than CC (P<.01, 95% confidence interval US$844–2154).

Conclusions

Despite the higher absolute cost of IC, its low incidence does not financially justify a routine prophylactic CC approach. In addition, no significant reduction in cholecystectomy-related complications was achieved by performing CC. An individualized approach taking identified risk factors for IC into consideration is recommended when deciding whether to perform prophylactic CC.  相似文献   
86.
OBJECTIVE: The growing awareness of female breast cancer has led to increased sensitivity toward pathologic breast conditions in children and adolescents. Thus, approximately 15% of patients in child and adolescent gynecology are referred for the first time because of conspicuous features of the breast such as pain, palpable masses, and other findings on visual inspection. The aim of this study was to analyze the underlying diagnoses and diseases and determine the status of breast sonography in the diagnostic process. METHODS: The study population consisted of 62 female patients between 8 weeks and 20 years of age (1997-2002) who were examined clinically, followed by standardized sonography (7.5-13 MHz, conventional B-mode panoramic sonography). Presumed diagnoses were confirmed by biopsy in some patients (n = 16) and by follow-up with clinical examination and sonography in most cases (n = 46). RESULTS: The clinical and sonographic evaluation confirmed 4 main groups of diagnoses: benign tumors (15), developmental disturbances (14), cystic changes (11), and inherent defects (7). In the remaining cases, the findings were no abnormality (9), nipple discharge without evidence of pathologic or morphologic correlates (3), abscesses (2), and epidermoid cyst (1). CONCLUSIONS: Knowledge of regular breast development and its variants is essential for the physician. Given knowledge of the sonographic appearance of physiologic breast development and specific lesions, breast sonography is most helpful in identifying and characterizing abnormalities and guiding further investigation.  相似文献   
87.

Introduction

The objective was to determine the effect of isolated soy protein (ISP) and flaxseed oil (FO) on inflammatory and oxidative stress indices, acute phase proteins, and wound healing of burn patients.

Methods

One hundred eighty-eight patients were assessed for eligibility in this randomized controlled trial. Of these, seventy-three eligible patients (total burn surface area 20–50%) were randomly assigned to 3 isocaloric groups, labeled as control (wheat flour + corn oil (CO)), ISP + FO, and ISP + CO, to receive these nutrients for 3 weeks. We used intention to treat analysis to overcome bias. Because of the large perturbation in water compartments, patients received nutrients from 4th to 25th day of admission. Serum high sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), superoxide dismutase (SOD), ferritin, albumin, and transferrin were measured. The wound area was evaluated by stereological test.

Results

During the 3-week intervention, hs-CRP (?19.4 ± 5.6, ?11.7 ± 4.7 μg/ml) and ferritin (?83.8 ± 20.5, ?80.1 ± 19.6 ng/ml) levels changes significantly reduced compared to the control group (P < 0.05). MDA level (?0.05 ± 0.21 μmol/l) significantly decreased in group A (P < 0/05) but was not significant in groups B and control (P > 0.05). Albumin level (0.59 ± 0.14, 0.30 ± 0.12 g/dl) significantly increased in group A compared to the control group (P < 0.05), but no significant relationship was found between other groups (P > 0.05). Transferrin level (4.9 ± 3.6, 2.9 ± 5.1 g/dl) significantly increased in ISP groups compared to the control (P < 0.05). SOD improved in all groups with no significant difference between them (P > 0.05). The stereology examination showed significant improvement in wound healing in the ISP groups on days 22 and 25 compared to the control group.

Conclusion

Nutritional supplements with ISP may attenuate post-burn oxidative stress and inflammation, leading to improved wound healing in burn patients. Flaxseed oil may not exert a beneficial effect over the ISP.  相似文献   
88.
89.

Objective:

Chylous fistulas can occur after neck surgery. Both nonoperative measures and direct fistula ligation may lead to fistula resolution. However, a refractory fistula requires upstream thoracic duct ligation. This can be accomplished minimally invasively. Success depends on lymphatic flow interruption where the duct enters the thorax. We report on the utility of frozen section confirmation in achieving this goal.

Methods:

Persistent chylous fistulas occurred in 2 patients after left cervical operations. In the first patient, attempted direct fistula ligation and sclerosant application failed. Fasting, parenteral nutrition, and somatostatin-analog provided no benefit. For the second patient, nonoperative treatment was also ineffective. Prior radiation therapy and multiple cervical operations militated against attempted direct fistula ligation. Both patients underwent thoracoscopic thoracic duct interruption.

Results:

In both cases, a duct candidate was identified between the aorta and azygos vein. Frozen section analysis of tissue resected between endoclips verified it as thoracic duct. Fistula resolution ensued promptly in both instances.

Conclusions:

This report lends further credence to the efficacy of minimally invasive thoracic duct ligation in treating postoperative cervical chylous fistulas. Frozen section confirmation of thoracic duct tissue is useful. It allows one facile with thoracoscopy, but less familiar with thoracic duct ligation, to confidently terminate the operation.  相似文献   
90.
Fourier transform infrared (FTIR) spectroscopy provides a unique molecular fingerprint of tissue from endogenous sources of light absorption; however, specific molecular components of the overall FTIR signature of precancer have not been characterized. In attenuated total reflectance mode, infrared light penetrates only a few microns of the tissue surface, and the influence of water on the spectra can be minimized, allowing for the analyses of the molecular composition of tissues. Here, spectra were collected from 98 excised specimens of the distal esophagus, including 38 squamous, 38 intestinal metaplasia (Barrett's), and 22 gastric, obtained endoscopically from 32 patients. We show that DNA, protein, glycogen, and glycoprotein comprise the principal sources of infrared absorption in the 950- to 1,800-cm(-1) regime. The concentrations of these biomolecules can be quantified by using a partial least-squares fit and used to classify disease states with high sensitivity, specificity, and accuracy. Moreover, use of FTIR to detect premalignant (dysplastic) mucosa results in a sensitivity, specificity, positive predictive value, and total accuracy of 92%, 80%, 92%, and 89%, respectively, and leads to a better interobserver agreement between two gastrointestinal pathologists for dysplasia (kappa = 0.72) versus histology alone (kappa = 0.52). Here, we demonstrate that the concentration of specific biomolecules can be determined from the FTIR spectra collected in attenuated total reflectance mode and can be used for predicting the underlying histopathology, which will contribute to the early detection and rapid staging of many diseases.  相似文献   
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