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In recent years there has been an intensive discussion about how to define a negative surgical resection margin. Despite the impact of radiation and systemic therapy a positive margin in breast surgery is associated with an increased risk of local recurrence. Thus, a positive margin confirmed by the pathologist results in further surgery that is troublesome for the patient in several ways and can also delay the initiation of adjuvant treatment. Therefore, the field of intraoperative margin assessment was intensively investigated and methods and technologies have been developed to support the breast surgeon in the operating theater. Some of these developments, such as frozen sections, touch imprint cytology, intraoperative ultrasound and radiofrequency spectroscopy are now established in the clinical routine. Others, such as near-infrared optical imaging, X-ray diffraction, high-frequency ultrasound and micro-computed tomography (CT) are still in the experimental stage. This article illustrates the current status of defining a negative surgical margin and gives an overview of the various and innovative technologies for intraoperative margin assessment.  相似文献   
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Converging evidence from clinical, preclinical, neuroimaging, and genetic research implicates dopamine neurotransmission in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The in vivo neuroreceptor imaging evidence also suggests alterations in the dopamine system in ADHD; however, the nature and behavioral significance of those have not yet been established. Here, we investigated striatal dopaminergic function in ADHD using [11C]raclopride PET with a d-amphetamine challenge. We also examined the relationship of striatal dopamine responses to ADHD symptoms and neurocognitive function. A total of 15 treatment-free, noncomorbid adult males with ADHD (age: 29.87±8.65) and 18 healthy male controls (age: 25.44±6.77) underwent two PET scans: one following a lactose placebo and the other following d-amphetamine (0.3 mg/kg, p.o.), administered double blind and in random order counterbalanced across groups. In a separate session without a drug, participants performed a battery of neurocognitive tests. Relative to the healthy controls, the ADHD patients, as a group, showed greater d-amphetamine-induced decreases in striatal [11C]raclopride binding and performed more poorly on measures of response inhibition. Across groups, a greater magnitude of d-amphetamine-induced change in [11C]raclopride binding potential was associated with poorer performance on measures of response inhibition and ADHD symptoms. Our findings suggest an augmented striatal dopaminergic response in treatment-naive ADHD. Though in contrast to results of a previous study, this finding appears consistent with a model proposing exaggerated phasic dopamine release in ADHD. A susceptibility to increased phasic dopamine responsivity may contribute to such characteristics of ADHD as poor inhibition and impulsivity.  相似文献   
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The relevance of breastfeeding and complementary feeding as proven child survival interventions, is well documented by the scientific research. These two preventive interventions can save as many as 19% of all child deaths. However, despite the volume of evidence favouring mainstreaming of these interventions, many countries, including India are yet to achieve universal appropriate infant and young child feeding practices. This article attempts to explore the evidenced based role of these interventions in the crusade to save children, and looks into the present scenario of infant and young child feeding in India, along with a possible road map to achieve high rates of early and exclusive breastfeeding and appropriate complementary feeding in the country.  相似文献   
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Background

Nanoparticles (NPs) play an important role in anticancer delivery systems. Surface modified NPs with hydrophilic polymers such as human serum albumin (HSA) have long half-life in the blood circulation system.

Methods

The method of modified nanoprecipitation was utilized for encapsulation of paclitaxel (PTX) in poly (lactic-co-glycolic acid) (PLGA). Para-maleimide benzoic hydrazide was conjugated to PLGA for the surface modifications of PLGA NPs, and then HSA was attached on the surface of prepared NPs by maleimide attachment to thiol groups (cysteines) of albumin. The application of HSA provides for the longer blood circulation of stealth NPs due to their escape from reticuloendothelial system (RES). Then the physicochemical properties of NPs like surface morphology, size, zeta potential, and in-vitro drug release were analyzed.

Results

The particle size of NPs ranged from 170 to 190 nm and increased about 20–30 nm after HSA conjugation. The zeta potential was about -6 mV and it decreased further after HSA conjugation. The HSA conjugation in prepared NPs was proved by Fourier transform infrared (FT-IR) spectroscopy, faster degradation of HSA in Differential scanning calorimetry (DSC) characterization, and other evidences such as the increasing in size and the decreasing in zeta potential. The PTX released in a biphasic mode for all colloidal suspensions. A sustained release profile for approximately 33 days was detected after a burst effect of the loaded drug. The in vitro cytotoxicity evaluation also indicated that the HSA NPs are more cytotoxic than plain NPs.

Conclusions

HSA decoration of PLGA NPs may be a suitable method for longer blood circulation of NPs.  相似文献   
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Placement of a drain following abdominal surgery is common despite a lack of convincing evidence in the current literature to support this practice. The use of intra-abdominal drain is associated with many potential and serious complications. We report a drain site evisceration of the right fallopian tube after the removal of an intra-abdominal drain. The drain was placed in the right iliac fossa in a patient who underwent a lower segment Caesarean section (LSCS) for meconium liquor with fetal distress. The Pfannenstiel incision made for LSCS was reopened and the protruding inflamed fimbrial end of the right fallopian tube was excised. The patient made an uneventful recovery. Routine intra-abdominal prophylactic drain following an abdominal surgery including LSCS should be discouraged.  相似文献   
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Fibromyalgia syndrome (FMS) is a condition of chronic muscle pain and fatigue of unknown etiology and pathogenesis. There is limited support for the various hypotheses espoused to account for the manifestations of FMS, including immunogenic, endocrine, and neurological mechanisms. Treatment, partially effective at best, is directed toward symptomatic relief without the benefit of targeting known, underlying pathology. A noteworthy commonality among partially effective therapies is a vasodilatory effect. This is true both of conventional treatments, unconventional treatments such as intravenous micronutrient therapy, and lifestyle treatments, specifically graduated exercise. The pain of fibromyalgia is described in terms suggestive of the pain in muscles following extreme exertion and anaerobic metabolism. Taken together, these characteristics suggest that the pain could be induced by vasomotor dysregulation, and vasoconstriction in muscle, leading to low-level ischemia and its metabolic sequelae. Vasodilatory influences, including physical activity, relieve the pain of FMS by increasing muscle perfusion. There are some preliminary data consistent with this hypothesis, and nothing known about FMS that refutes it. The hypothesis that the downstream cause of FMS symptoms is muscle hypoperfusion due to regional vasomotor dysregulation has clear implications for treatment; is testable with current technology; and should be investigated.  相似文献   
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ObjectivesThe purpose of our study was to test our hypothesis that multiparametric magnetic resonance imaging (mpMRI) may have a higher prognostic accuracy than the Partin tables in predicting organ-confined (OC) prostate cancer and extracapsular extension (ECE) after radical prostatectomy (RP).Methods and materialsAfter institutional review board approval, we retrospectively reviewed 60 patients who underwent 3-T mpMRI before RP. mpMRI was used to assess clinical stage and the updated version of the Partin tables was used to calculate the probability of each patient to harbor OC disease. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mpMRI in detecting OC and ECE were calculated. Logistic regression models predicting OC pathology were created using either clinical stage at mpMRI or Partin tables probability. The area under the curve was used to calculate the predictive accuracy of each model.ResultsMedian prostate-specific antigen level at diagnosis was 5 ng/ml (range: 4.1–6.7 ng/ml). Overall, 52 (86.7%) men had cT1 disease, 7 (11.7%) had cT2a/b, and 1 (1.6%) had cT3b at digital rectal examination. Biopsy Gleason score was 6, 3+4 = 7, 4+3 = 7, 8, and 9 to 10 in 28 (46.7%), 15 (25%), 3 (5%), 10 (16.7%), and 4 (6.6%) patients, respectively. At mpMRI, clinical stage was defined as cT2a/b, cT2c, cT3a, and cT3b in 11 (18.3%), 23 (38.3%), 21 (35%), and 5 (8.4%) patients, respectively. At final pathology, 38 men (63.3%) had OC disease, whereas 18 (30%) had ECE and 4 (6.7%) had seminal vesicle invasion.The sensitivity, specificity, PPV, and NPV of mpMRI in detecting OC disease were 81.6%, 86.4%, 91.2%, and 73.1%, respectively, whereas in detecting ECE were 77.8%, 83.4%, 66.7%, and 89.7%, respectively. At logistic regression, both the Partin tables–derived probability and the mpMRI clinical staging were significantly associated with OC disease (all P<0.01). The area under the curves of the model built using the Partin tables and that of the mpMRI model were 0.62 and 0.82, respectively (P = 0.04).ConclusionsThe predictive accuracy of mpMRI in predicting OC disease on pathological analysis is significantly greater than that of the Partin tables. mpMRI had a high PPV (91.2%) when predicting OC disease and a high NPV (89.7%) with regard to ECE. mpMRI should be considered when planning prostate cancer treatment in addition to readily available clinical parameters.  相似文献   
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