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61.
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INTRODUCTION: Surgical treatment of third nerve palsy, sensory exotropia and strabismus secondary to anomalous innervation of the rectus muscles, frequently require large rectus muscle recessions in an attempt to maintain alignment in the primary position and reduce the effects of misinnervation. The aim of this study was to describe and evaluate the results of inactivation of a rectus muscle by its attachment to the adjacent orbital wall. METHODS: Seven subjects diagnosed with third-nerve palsy (three cases), Duane syndrome (two cases), sensory exotropia (one case), and congenital aberrant innervation of vertical rectus muscles (one case) underwent rectus muscle inactivation by orbital wall fixation. The rectus muscle was disinserted from the globe and reattached to the adjacent orbital periosteum using non-absorbable sutures. This surgery was performed on the lateral rectus muscle in six subjects, and surgery was performed on both ipsilateral vertical rectus muscles in one. RESULTS: Postoperatively four of six patients were aligned within 12 prism diopters of orthotropia in primary position. All patients had improvement of the anomalous head posture. In Duane syndrome, lateral rectus inactivation markedly reduced co-contraction and globe retraction. No overcorrections resulted. CONCLUSION: A rectus muscle may be functionally inactivated when its insertion is attached to the orbital periosteum. Advantages of this procedure over extirpation and free tenotomy include permanent disinsertion of the muscle from globe and reversibility.  相似文献   
63.
Recent reports have described neurobehavioral impairments in human subjects carrying a V66M polymorphism in the gene encoding brain-derived neurotrophic factor (BDNF). Inasmuch as ventral nervous system (CNS) deficits associated with this BDNF polymorphism are similar to those observed among subjects with chronic exposure to elemental mercury (Hg degrees ), we examined the potential effect of this BDNF polymorphism on symptoms and mood in an established cohort of dental practitioners with chronic low-level Hg degrees exposure. Self-reported symptoms and mood were obtained by computerized questionnaire from 193 male dentists (DTs) and 230 female dental assistants (DAs). Spot urine samples were analyzed for mercury concentrations to evaluate recent exposure. Detailed work histories were obtained to calculate chronic indices of Hg degrees exposure. Buccal cell samples were obtained to identify the V66M polymorphism of BDNF. Scores for 11 current and 12 recent and chronic symptom groups, along with six mood factors, were evaluated with respect to recent and chronic Hg degrees exposure and BDNF polymorphism. Multiple regression analysis controlled for age, race, socioeconomic status, tobacco and alcohol use, self-reported health problems, and medications. Separate evaluations were conducted for DTs and DAs. Twenty-three associations between recent or chronic Hg degrees exposure and BDNF status and self-reported symptoms were observed with p < 0.10. All but three were in the expected direction (symptom scores increasing with Hg degrees exposure or BDNF polymorphism), and all but six were among DAs. All eight correlations between chronic exposure indices and recent and chronic symptoms among DAs were in the expected direction. All seven associations between BDNF and symptoms were in the expected direction and split between DTs and DAs. All three associations with mood factors were among DAs and in the expected direction. These results indicate that among DAs very low levels of occupational Hg degrees exposure are associated with increased symptoms. The BDNF polymorphism is also associated with increased symptom and mood scores. Notably, Hg degrees and BDNF polymorphism were additive with respect to their associations with the same symptom group.  相似文献   
64.
Ramucirumab plus paclitaxel is considered the standard of care in the second-line treatment of gastric carcinoma (GC). The aim of this study was to evaluate plasma vascular endothelial growth factor-A (VEGF-A), VEGF-D, and circulating soluble VEGF receptor-2 (sVEGFR-2) as possible markers of resistance or response to ramucirumab administered with paclitaxel in pretreated metastatic GC patients. Plasma samples were collected at different time points (on days 1 and 15 of the first 3 cycles, at best radiologic response and at disease progression). VEGF-A, VEGF-D and sVEGFR-2 were analysed by ELISA. Correlations of biomarker baseline levels or dynamic changes with outcome measures were assessed. Progression-free survival (PFS) was the primary endpoint of the study. Forty-one patients were enrolled. VEGF-A and VEGF-D, but not sVEGFR-2, values significantly increased during treatment compared to baseline (P < 0.001). A positive correlation between VEGF-A and sVEGFR-2 at cycle 2 was found (P=0.045). At univariate analysis, higher baseline levels of VEGF-A were associated with worse OS (P=0.015). Early increase of sVEGFR-2 levels after the first treatment cycle was the only factor associated with longer PFS (6.6 vs. 3.6 months, P=0.049) and OS (18.6 vs. 5.2 months, P=0.008). Significance of sVEGFR-2 early increase was retained at multivariate analysis for OS (HR 0.32; 95% CI 0.12-0.91; P=0.032). The reported results confirmed the prognostic role of baseline VEGF-A and, with the limitations of the limited sample size and the lack of a control arm, suggested that the early increase of sVEGFR-2 after 1 cycle of treatment could be a potential predictive biomarker of benefit from second-line ramucirumab plus paclitaxel in GC.  相似文献   
65.
Nanoporous Au has been subjected to serial block face-scanning electron microscopy (SBF-SEM) 3D-characterisation. Corresponding sections have been digitalized and used to evaluate the associated mechanical properties. Our investigation demonstrates that the sample is homogeneous and isotropic. The effective Young’s modulus estimated by an analytical multiscale approach agrees remarkably well with the values stated in the literature.  相似文献   
66.
Irinotecan is a topoisomerase inhibitor, widely used in treatment of malignancies including pancreatic ductal adenocarcinoma (PDAC) as part of the FOLFIRINOX regimen prescribed as a first‐line treatment in several countries. However, irinotecan has not been successfully introduced as a second‐line treatment for pancreatic cancer and few randomized clinical studies have evaluated its added value. Efficacy of liposomal irinotecan (nal‐IRI) combined with 5‐fluorouracil and leucovorin (5‐FU/LV) was reported in the phase III NAPOLI‐1 trial in metastatic PDAC following failure of gemcitabine‐based therapy. Several features of nal‐IRI pharmacokinetics (PK) could result in better outcomes versus nonliposomal irinotecan. Irinotecan is a prodrug that is converted to active SN‐38 by carboxylesterase enzymes and inactivated by cytochrome P450 3A4/3A5. SN‐38 is inactivated by UGT1A1 enzymes. Individual variations in their expression and activity could influence enhanced localized irinotecan activity and toxicity. Liposomal irinotecan exploits the enhanced permeability and retention effect in cancer, accumulating in tumor tissues. Liposomal irinotecan also has a longer half‐life and higher area under the concentration‐time curve (0–∞) than nonliposomal irinotecan, as the liposomal formulation protects cargo from premature metabolism in the plasma. This results in irinotecan activation in tumor tissue, leading to enhanced cytotoxicity. Importantly, despite the longer exposure, overall toxicity for nal‐IRI is no worse than nonliposomal irinotecan. Liposomal irinotecan exemplifies how liposomal encapsulation of a chemotherapeutic agent can alter its PK properties, improving clinical outcomes for patients. Liposomal irinotecan is currently under investigation in other malignancies including biliary tract cancer (amongst other gastrointestinal cancers), brain tumors, and small‐cell lung cancer.  相似文献   
67.
Chest tubes are routinely inserted after thoracic surgery procedures in different sizes and numbers. The aim of this study is to assess the efficacy of Smart Drain Coaxial drainage compared with two standard chest tubes in patients undergoing thoracotomy for pulmonary lobectomy. Ninety-eight patients (57 males and 41 females, mean age 68.3 ± 7.4 years) with lung cancer undergoing open pulmonary lobectomy were randomized in two groups: 50 received one upper 28-Fr and one lower 32-Fr standard chest tube (ST group) and 48 received one 28-Fr Smart Drain Coaxial tube (SDC group). Hospitalization, quantity of fluid output, air leaks, radiograph findings, pain control and costs were assessed. SDC group showed shorter hospitalization (7.3 vs. 6.1 days, p = 0.02), lower pain in postoperative day-1 (p = 0.02) and a lower use of analgesic drugs (p = 0.04). Pleural effusion drainage was lower in SDC group in the first postoperative day (median 400.0 ± 200.0 mL vs. 450.0 ± 193.8 mL, p = 0.04) and as a mean of first three PODs (median 325.0 ± 137.5 mL vs. 362.5 ± 96.7 mL, p = 0.01). No difference in terms of fluid retention, residual pleural space, subcutaneous emphysema and complications after chest tubes removal was found. In conclusion, Smart Drain Coaxial chest tube seems a feasible option after thoracotomy for pulmonary lobectomy. The SDC group showed a shorter hospitalization and decreased analgesic drugs use and, thus, a reduction of costs.  相似文献   
68.
INTRODUCTION: Diagnostic imaging by magnetic resonance imaging (MRI) or computed x-ray tomography (CT) has become the standard of care in many medical fields. Clinical imaging of the extraocular muscles (EOMs) can now provide insight into some causes of strabismus, in some cases challenging traditional concepts of etiology and suggesting alternative treatments. METHODS: Between 1990 and 2001, 62 orthotropic volunteers and 261 strabismic patients underwent orbital imaging under a prospective protocol. Surface coil MRI was performed with fixation control with slice thickness of 1.5 to 3 mm; CT was performed with 1-mm slice thickness. Images were correlated with ophthalmological examinations. RESULTS: MRI was performed in 267 and CT in 56 subjects. Comparison with normal orbits commonly demonstrated abnormalities of EOM size or location in strabismic patients. These included absence (5 patients) or atrophy (33 patients) of the superior oblique (SO) muscle in SO palsy; abnormalities of the trochlea or SO tendon in Brown's syndrome (8 patients); heterotopy of the rectus pulleys associated with incomitant strabismus (46 patients), including instability of pulleys (9 patients); trauma to rectus EOMs (16 patients); atrophy of the lateral rectus (10 patients), inferior rectus (4 patients), medial rectus (4 patients), superior rectus (4 patients), and inferior oblique (1 patient) muscles; and EOMs disinserted by scleral buckles (3 patients). EOM abnormalities correlated closely with clinically abnormal patterns of ocular motility. CONCLUSIONS: With the appropriate technique, EOM imaging is a valuable adjunct in clinical evaluation of complex strabismus. Because imaging can provide unique information unavailable from the clinical examination alone, it should be performed when indicated to evaluate patients with strabismus more complex than concomitant esotropia and exotropia.  相似文献   
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70.
ObjectiveWe aimed to evaluate the accuracy of sentinel lymph node (SLN) mapping with transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) to detect lymph node (LN) metastases, in patients with intermediate and high-risk endometrial cancer (EC), focusing on its performance to detect paraaortic involvement.MethodsProspective study including women with preoperative intermediate or high-risk EC, according to ESMO-ESGO-ESTRO consensus, who underwent SLN mapping using the TUMIR approach. SLNs were preoperatively localized by planar and single photon emission computed tomography/computed tomography images, and intraoperatively by gamma-probe. Immediately after SLN excision, all women underwent systematic pelvic and paraaortic lymphadenectomy by laparoscopy.ResultsThe study included 102 patients. The intraoperative SLN detection rate was 79.4% (81/102). Pelvic and paraaortic drainage was observed in 92.6% (75/81) and 45.7% (37/81) women, respectively, being exclusively paraaortic in 7.4% (6/81). After systematic lymphadenectomy, LN metastases were identified in 19.6% (20/102) patients, with 45.0% (9/20) showing paraaortic involvement, which was exclusive in 15.0% (3/20). The overall sensitivity and negative predictive value (NPV) of SLNs by the TUMIR approach to detect lymphatic involvement were 87.5% and 97.0%, respectively; and 83.3% and 96.9%, for paraaortic metastases. After applying the MSKCC SLN mapping algorithm, the sensitivity and NPV were 93.8% and 98.5%, respectively.ConclusionThe TUMIR method provides valuable information of endometrial drainage in patients at higher risk of paraaortic LN involvement. The TUMIR approach showed a detection rate of paraaortic SLNs greater than 45% and a high sensitivity and NPV for paraaortic metastases in women with intermediate and high-risk EC.  相似文献   
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