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61.
ObjectivesDetermining clinicopathologic features that stratify the risk of disease progression in patients with seminal vesicle invasion at radical prostatectomy remains critical for patient counseling, clinical trial enrollment, and the judicious application of secondary therapies. Then, we evaluated the prognostic significance of concomitant extracapsular extension (ECE) in patients with seminal vesicle invasion and negative lymph nodes at radical prostatectomy.MethodsWe identified 1,132 patients who underwent prostatectomy between 1987 and 2009 and were found to have pT3bN0 disease. Median postoperative follow-up was 10.6 years (interquartile range, 5.9–15.3). Survival was estimated using the Kaplan-Meier method and compared for patients with and without ECE with the log-rank test. The association of ECE with outcome was evaluated using Cox proportional hazards regression models.ResultsA total of 693 (61%) patients were noted to have ECE. Compared with pT3bN0 patients without ECE, patients with pT3bN0 tumors and ECE had a significantly worse 15-year biochemical recurrence-free survival (29% vs. 39%; P<0.001), systemic progression-free survival (71% vs. 81%; P<0.001), cancer-specific survival (80% vs. 89%; P<0.001), and overall survival (50% vs. 63%; P<0.001). On multivariate analysis, the presence of ECE was associated with significantly increased risks of systemic progression (hazard ratio [HR], 1.56; P=0.006), death from prostate cancer (HR, 1.71; P=0.01), and all-cause mortality (HR, 1.35; P=0.007). Meanwhile, adjuvant hormonal therapy, which was received by 334 patients (29.5%), was associated with significantly decreased risks of systemic progression (HR, 0.50; P=0.0004) and cancer death (HR, 0.57; P=0.03), but not all-cause mortality (HR, 0.81; P=0.09). Limitations included retrospective design and nonstandardized application of secondary treatments.ConclusionsThe presence of ECE in patients with pT3bN0 prostate cancer is associated with increased risks of systemic progression and cancer death. Pending validation, ECE may be incorporated into risk stratification or staging classification or both. Meanwhile, these patients continue to represent ideal candidates for adjuvant therapy trials.  相似文献   
62.
We considered if the cyanosis frequently observed during a cough attack in patients with chronic lung disease was due to worsening hypoxemia. To investigate the effects of cough on PaO2, we measured arterial blood gases before and after a voluntary coughing period of 45 sec, in 11 patients with Interstitial Lung Disease (ILD) and 14 patients with Chronic Obstructive Lung Disease (COPD). All patients significantly increased (p < 0.05) their PaO2 (COPD: from 49 ± 2 to 60 ± 2 mmHg; ILD from 44 ± 2 to 51 ± 3 mmHg, mean ± SD) and decreased their PaCO2. We conclude that stable patients with COPD and ILD increase their PaO2 with coughing most likely due to hyperventilation. The cyanosis observed could be due to peripheral circulatory effects of coughing.  相似文献   
63.

Background/Purpose

Living donor liver transplantation has become a cornerstone for the treatment of children with end-stage hepatic dysfunction, especially within populations or countries with low rates of organ utilization from deceased donors. The objective is to report our experience with 185 living donors operated on by a team pediatric surgeons in a tertiary center for pediatric liver transplantation.

Methods

Retrospective analysis of medical records of donors of hepatic grafts for transplant undergoing surgery between June 1998 and March 2013.

Results

Over the last 14 years, 185 liver transplants were performed in pediatric recipients of grafts from living donors. Among the donors, 166 left lateral segments (89.7%), 18 left lobes without the caudate lobe (9.7%) and 1 right lobe (0.5%) were harvested. The donor age ranged from 16 to 53 years, and the weight ranged from 47 to 106 kg. In 10 donors, an additional graft of the donor inferior mesenteric vein was harvested to substitute for a hypoplastic recipient portal vein. The transfusion of blood products was required in 15 donors (8.1%). The mean hospital stay was 5 days. No deaths occurred, but complications were identified in 23 patients (12.4%): 9 patients experienced abdominal pain and severe gastrointestinal symptoms and 3 patients required reoperations. Eight donors presented with minor bile leaks that were treated conservatively, and 3 patients developed extra-peritoneal infections (1 wound collection, 1 phlebitis and 1 pneumonia). Eight grafts (4.3%) showed primary dysfunction resulting in recipient death (3 cases of fulminant hepatitis, 1 patient with metabolic disease, 1 patient with Alagille syndrome and 3 cases of biliary atresia in infants under 1 year old). There was no relation between donor complications and primary graft dysfunction (P = 0.6).

Conclusions

Living donor transplantation is safe for the donor and presents a low morbidity. The donor surgery may be performed by a team of trained pediatric surgeons.  相似文献   
64.
ObjectivesTo assess levonorgestrel (LNG) and ulipristal acetate (UPA) availability in pharmacies in a metropolitan area.MethodsA cross-sectional survey was conducted of all identified pharmacies within 25 miles of an urban medical center in Kansas City, KS. We categorized the pharmacies as dedicated commercial (national chains), store-associated (affiliated with a general merchandise or grocery store), or independent. We assessed LNG and UPA availability or time to availability if not currently stocked.ResultsWe contacted 165 pharmacies. Of the 165 pharmacies, few stocked UPA (12/165, 7%) whereas the majority stocked oral LNG (128/165, 78%). Dedicated commercial pharmacies were more likely to carry UPA than store-associated and independent pharmacies (11/84 [13%] vs. 1/61 [1%] vs. 0/20, respectively; P = 0.016). Most pharmacies that did not stock UPA reported that they could obtain it within 24 hours (94/153, 62%). Dedicated commercial pharmacies were most likely report the ability to obtain UPA in 24 hours (P = 0.016).ConclusionFew pharmacies stock UPA, the most effective form of oral emergency contraception. Enhanced communication between medical providers and pharmacists within current laws and regulations could enhance patient access to UPA.  相似文献   
65.
Melatonin and its indoles derivatives are central in the synchronization of malaria parasites. In this research, we discovered that melatonin is unable to increase the parasitemia in the human malaria Plasmodium falciparum that lacks the kinase PfeIK1. The PfeIK1 knockout strain is a valuable tool in the screening of indol-related compound that blocks the melatonin effect in wild-type (WT) parasite development. The assays were performed by using flow cytometry with simultaneous labeling for mitochondria viability with MitoTracker Deep Red and nucleus staining with SYBR Green. We found that Melatotosil leads to an increase in parasitemia in P. falciparum and blocks melatonin effect in the WT parasite. Using microscopy imaging system, we found that Melatotosil at 500 nM is able to induce cytosolic calcium rise in transgenic PfGCaMP3 parasites. On the contrary, the compound Triptiofen blocks P. falciparum cell cycle with IC50 9.76 µM ± 0.6, inhibits melatonin action, and does not lead to a cytosolic calcium rise in PfGCaMP3 parasites. We also found that the synthetic indol-related compounds arrested parasite cycle for PfeIK1 knockout and (WT) P. falciparum (3D7) in 72 hours culture assays with the IC50 values slighting lower for the WT strain. We concluded that the kinase PfeIK1 is central for melatonin downstream signaling pathways involved in parasite cell cycle progression. More importantly, the indol-related compounds block its cycle as an upstream essential mechanism for parasite survival. Our data clearly show that this class of compounds emerge as an alternative for the problem of resistance with the classical antimalarials.  相似文献   
66.
67.
The use of erbium lasers to prevent caries in enamel has shown positive results. However, it is not known if Er,Cr:YSGG laser can also be used to increase acid resistance of root dentine, which is another dental tissue susceptible to the action of cariogenic bacteria.

Objective

To analyze the effects of the Er,Cr:YSGG laser (λ=2.78 μm, 20 Hz) irradiation associated with 2% neutral sodium fluoride (NaF) to prevent root dentin demineralization.

Material and Methods

One hundred human root dentin samples were divided into 10 groups (G) and treated as follows: G1: no treatment; G2: NaF; G3: laser (4.64 J/cm2) with water cooling (WC=5.4 mL/min); G4: laser (4.64 J/cm2) without WC; G5: laser (8.92 J/cm2) with WC; G6: laser (8.92 J/cm2) without WC; G7: laser (4.64 J/cm2) with WC and NaF; G8: laser (4.64 J/cm2) without WC and NaF; G9: laser (8.92 J/cm2) with WC and NaF; G10: laser (8.92 J/cm2) without WC and NaF. The NaF gel was applied alone or after 4 min of irradiation. After 14 days of acid challenge, the samples were sectioned and the Knoop microhardness (KHN) test was done at different depths (30, 60, 90 and 120 μm) from the outer dentin surface. Data were analyzed by one-way ANOVA and Fisher''s test (α=5%).

Results

The results showed that G8 and G10 presented higher KHN than the G1 for the depths of 30 and 60 μm, indicating an increase of the acid resistance of the dentin in up to 35% (p<0.05).

Conclusions

The use of Er,Cr:YSGG laser irradiation at 4.64 J/ cm2 and 8.92 J/cm2 without water cooling and associated with 2% NaF can increase the acid resistance of human root dentin.  相似文献   
68.
IntroductionThe aim of this study is to determine whether the incidence of hypothyroidism in patients with Head and Neck Cancer who have undergone neck radiotherapy justifies the inclusion of thyroid function monitoring in the pre-operative and follow-up evaluation protocols.Material and methodsA retrospective study was conducted with all the patients seen in the Oncology Section of the Otorhinolaryngology Department in the “Hospital de Clínicas”, Montevideo, Uruguay, from January 1970 to May 2008. A total of 550 case records were analyzed. Of the 550 patients, 188 were excluded due to the fact they had not received radiotherapy as part of their treatment and 362 were included in the study. Of these, 55 patients had thyroid stimulating hormone (TSH) level determination after treatment with radiation therapy. Hypothyroidism was defined as a TSH value greater than or equal to 4.5 mIU/L, regardless of whether or not any symptoms were presented.Results36.4% of the patients were diagnosed as having clinical or sub-clinical hypothyroidism. The type of treatment carried out, particularly whether or not surgical resection was performed, was found to be the most significant predictive factor for the development of hypothyroidism (P=0.054).ConclusionMonitoring of the thyroid function on a six-month or annual basis, at least during the first 5 post-treatment years, has to be included in the follow-up and control protocols of every patient undergoing neck RT, and patients with TSH values over 4.5 mIU/L should be referred to the endocrinologist for hormone replacement, whether they present symptoms or not.  相似文献   
69.
Prochlorococcus is a marine cyanobacterium responsible for a significant part of global primary production as well as being one of the most abundant organisms on Earth. Protein turnover is an essential and poorly understood aspect of the cyanobacterial response to environmental stresses. In the present work, cultures of the SS120 and MIT9313 strains were subjected to several conditions, and quantitative real time RT-PCR was used to measure changes in the expression of genes encoding three representative ATP-dependent proteases. We found common responses to conditions such as aging. However, the expression pattern under nutrient starvation was strikingly different in the two strains, probably reflecting the different regulatory backgrounds of the two ecotypes here studied.  相似文献   
70.
To determine whether increased migration is associated with an increase in incidence of toxocariasis (visceral larva migrans), we analyzed clinical data obtained from immigrants from Latin America. Although infection with Toxocara sp. roundworm larvae is distributed worldwide, seroprevalence is highest in tropical and subtropical areas.  相似文献   
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