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71.
Neutral red (NR) is a cationic, nontoxic vital dye employed as a histologic stain for proliferating cells; it has been used clinically for photodynamic treatment of herpes simplex virus lesions. NR is selectively taken up and concentrated by mitotic cells, an important characteristic for more effective antineoplastic agents. In the present study, UCLA-SO-P3 human squamous carcinoma cells displayed minimal toxicity when incubated with up to 50 μg/ml NR in the absence of light. However, cells incubated with greater than 0.5μg/ml NR followed by exposure to KTP laser light at 532 nm exhibited nearly 100% tumor cell death. The degree of cell toxicity was proportional to NR dose and laser light fluence. This study demonstrates that NR is an excellent cancer cell photosensitizer in vitro, and, after adding additional in vivo preclinical testing, may prove to be a useful agent in photodynamic destruction of head and neck tumors.  相似文献   
72.
Up-regulation of matrix metalloproteinases MMP-9 and MMP-2 after injury to the spinal cord (SCI) is demonstrated. MMP-9 activity maximized at 12-24 h, and MMP-2 rose at 5 days post-injury. MMP-3 was not detectable by zymographic analysis, so its level of expression was, at most, very low. The level of tissue inhibitor of metalloproteinases in the spinal cord was not altered by injury, perhaps permitting increased MMP-9 and MMP-2 activities in situ. Ablating them with an antibody demonstrated that infiltrating neutrophils were the principal source of MMP-9 activity after spinal cord injury, suggesting that neutrophils utilize that proteinase in responding to spinal cord injury. MMP-9 and MMP-2 probably contribute to breakdown of the extracellular matrix following SCI.  相似文献   
73.
Extended cervical mediastinoscopy in the staging of bronchogenic carcinoma   总被引:3,自引:0,他引:3  
BACKGROUND: Extended cervical mediastinoscopy (ECM) is a technique in the staging of bronchogenic carcinoma described first by Ginsberg in 1984. To update our experience we have prospectively evaluated our results on 106 patients who underwent the technique from 1985 to 1998. METHODS: The ECM technique is performed once the operability of the patient has been evaluated, according to the computed tomography findings. The intervention is carried out at the same time as a standard cervical mediastinoscopy through the same incision following the same technique as previously published. The ECM is considered positive when metastatic nodes or tumor involvement directly in the paraaortic or subaortic regions is detected and confirmed histologically. Negative cases of ECM and positive cases of standard cervical mediastinoscopy are excluded from this study. A false-negative ECM is defined as the presence of infiltrated adenopathies at the paraortic level detected on postoperative histologic study. RESULTS: We had performed ECM in 106 patients, and a total of 13 were subsequently excluded for the reasons stated above. Of the remaining cases, 26 were positive, 61 negative and 6 had false-negative results with no false-positive results. Sensitivity was 81.2%, specificity 100%, accuracy 93.3%, positive predictive value 100%, and negative predictive value 91%. There were no complications with the technique. CONCLUSIONS: We conclude that ECM is a useful technique for staging bronchogenic carcinoma that allows samples to be taken from paraortic and subaortic regions with minimally invasive techniques.  相似文献   
74.
Aprotinin is a protease inhibitor of interest for its antifibrinolytic effect of reducing perioperative bleeding in certain types of surgery, with wide use in heart surgery, liver transplantation and vascular surgery. The application of aprotinin during orthopedic surgery has recently been suggested. Such use is controversial, as there is lack of consensus as to the type of patient for whom aprotinin administration would be indicated, the surgical procedure during which it would be most effective (hip or knee arthroplasty, spinal arthrodesis, major tumor or septic surgery), the doses to administer, its safety and its real efficacy for conserving homologous blood. That is to say, there is no agreement as to the cost/benefit relation of aprotinin for the various types of orthopedic surgery. This critical review of the literature leads to the conclusion that aprotinin is a promising drug for use in orthopedic surgery, given that published studies have established the benefit in blood product savings and decreased blood loss during surgery.  相似文献   
75.
BackgroundKnown in the past for its toxic aspect as the main urban pollutant, in the last few decades, ozone has been gaining greater visibility for its possible antimicrobial, antiviral, and antioxidant effects when used in human dermatological pathologies. Despite the reports of clinical benefits, the standard dosage for clinical efficacy and safety are yet not clear, nor are its means of application and its true acting mechanism.ObjectiveWe conducted a review to determine the efficacy and safety of ozone therapy for a variety of dermatological conditions.MethodsWe considered clinical trials (both randomized and non-randomized) published between December 2020 and March 2021 as long as they provided some PICO information, i.e., population (P), intervention (I), and study design. The skin dermatological conditions researched were: acne, dermatitis, psoriasis, systemic sclerosis, herpes, aging, ulcers, and skin scarring.ResultsA total of 326 articles were identified and 150 remained after duplicates were removed. After titles, abstracts and full articles were read, 17 articles were included in the systematic review (with 643 patients). ConclusionOzone therapy seems promising for some dermatological conditions; however, the articles included in this review had methodological limitations and did not sufficiently demonstrate sound evidence for safe therapy. Therefore, more studies with better methodological standards and longer-term assessments of side effects should be conducted to achieve better standards and safety in ozone therapy for dermatological conditions.  相似文献   
76.
77.

Background

Somatic v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutation, present in approximately 10% of metastatic colorectal cancer (mCRC) cases, is associated with poor prognosis. Patient outcome outside of clinical trials has only been reported in small series. We report real-world data on treatment and survival for BRAF-mutated (MT) patients at a single tertiary center, compared with a matched BRAF wild type (WT) control group.

Patients and Methods

All colorectal cancer patients tested for BRAF mutation, from October 2010 to November 2014 were identified. BRAF-MT mCRC cases were compared with an age and sex-matched BRAF-WT control group. Clinicopathological data were collected and survival calculated using the Kaplan–Meier method and comparisons made using Cox regression.

Results

Forty-three of 503 patients (8.5%) tested had BRAF-MT mCRC and were compared with 88 BRAF-WT controls. Median overall survival (mOS) was 18.2 months for BRAF-MT and 41.1 months for BRAF-WT mCRC patients (hazard ratio, 2.74; 95% confidence interval, 1.60-4.70; P < .001). Progression-free survival for BRAF-MT and WT patients, respectively, was: 8.1 months versus 9.2 months (P = .571) first-line, 5.5 months versus 8.3 months (P = .074) second-line, and 1.8 months versus 5.6 months (P = .074) third-line. Treatment using sequential fluoropyrimidine-based doublet chemotherapy was similar between both groups. Anti-epidermal growth factor receptor (EGFR) therapy was mainly given third-line with progressive disease in 90% (n = 9 of 10) of BRAF-MT patients at first restaging.

Conclusion

In this case-control study, the poor mOS of BRAF-MT mCRC was associated with reduced treatment benefit beyond first-line. Sequential doublet chemotherapy remains a reasonable option in appropriately selected patients. BRAF-MT patients did not benefit from anti-EGFR therapy in this study. Recruitment to clinical trials is recommended to improve outcomes in BRAF-MT mCRC.  相似文献   
78.

Objective

We aimed to study the cross-sectional area of levator ani muscle and the doppler velocimetric parameters of vessels its in premenopausal and postmenopausal women.

Study design

Sixty-four patients, divided into 3 groups, were assessed: group I (20 women—average age 28 years) premenopausal and nulliparous (control); group II (24 women—average age 38 years, vaginal delivery 1–4) premenopausal with vaginal deliveries; group III (20 women—average age 55 years, parity 0–4) postmenopausal without hormonal therapy. Doppler velocimetry of levator ani muscle vessels through resistance and pulsatility indices was used and the means of the groups compared by adjusting the weighed variance model with multiple comparisons, according to Tukey's method. Similarly, we measured the cross-sectional area of the muscle using ultrasonography.

Results

There was a significant increase in resistance and pulsatility indices in postmenopausal patients as compared to the other two groups. We also observed a significant decrease in the cross-sectional area of the muscle of postmenopausal patients when compared to those in premenopausal.

Conclusion

The obtained results allow us to conclude that levator ani muscle vascularization significantly decreases after menopause (age and/or hipoestrogenism) and that it can be assumed that vaginal delivery does not promote long-term alterations in levator ani muscle vascularization. We also observed a significant decrease in the cross-sectional area of the muscle in postmenopausal women when compared to those in premenopausal.  相似文献   
79.
Introduction of Doppler ultrasound in obstetrical practice has changed both management and understanding of several diseases that put at risk women and them fetuses. To establish necessary basics and correctly apply this technique, this review will focus in physical principles, acquisition methods, consistency, and safety issues of Doppler ultrasound, in order to improve precision, accuracy and interpretation of this methodology.  相似文献   
80.
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