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71.
Although abnormalities in serotonergic function have been the major focus of studies on suicidal behavior, several studies indicate that abnormalities of noradrenergic function may also be involved in the pathophysiology of suicide. In this paper, we have reviewed some of the noradrenergic studies in sucide, including studies of the biosynthetic enzyme for norepinephrine, tyrosine hydroxylase (TH), the receptors for norepinephrine, α- and β-adrenergic receptors, as well as the signaling cascades linked to β-adrenergic receptors. In general, these studies indicate that the protein expression of TH, as well as α2- and β2-adrenergic receptors, is increased in the postmortem brain of suicide victims. More studies are needed in order to examine extensively the role of noradrenergic function in suicidal behavior.  相似文献   
72.
Cypripedium kentuckiense is one of the 15 Cypripedium species found in North America. Its populations are threatened by illegal collection and land conversion. Assessing the level of genetic variation within-and-among populations employing species-specific and variable co-dominant molecular markers such as microsatellite can assist in developing appropriate conservation strategies. For the first time, we report eight polymorphic nuclear microsatellite markers for C. kentuckiense. Number of alleles per locus ranged from two to eight and the mean number of alleles across eight loci was 4.13. Mean observed (H o ) and expected heterozygosity (H e ) values were 0.514 and 0.522, respectively. The eight markers reported in this study can be used to estimate genetic diversity, genetic structure, gene flow, and mating system of the species.  相似文献   
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74.
The present case report highlights that a tense mega-sized aortic root and ascending aorta can mechanically resist the passage of fully inflated (1.5 ml air) balloon to wedge-trace position in the pulmonary artery. Any attempt to push the catheter rather predisposed its recoiling and rebutting into the right ventricle and the cardiac arrhythmia. Inflating continuous cardiac output catheter balloon with lesser volume of air (1 ml) is suggested to overcome this problem.  相似文献   
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A Nb4C3Tx (MXene)-modified glassy carbon electrode was used for the electrochemical detection of Pb2+ ions in aqueous media. The sensing platform was evaluated by anodic stripping analysis after optimizing the influencing factors such as pH, deposition potential, and time. The large interlayer spacing, high c lattice parameter and higher conductivity of Nb4C3Tx compared to other MXenes enhance the electrochemical detection of Pb2+. The developed sensor can reach a detection limit of 12 nM at a potential ∼−0.6 V. Additionally, the developed sensor showed promising selectivity in the presence of Cu2+ and Cd2+, and stability for at least 5 cycles of continuous measurements with good repeatability. This work demonstrates the potential applications of Nb4C3Tx towards the development of effective electrochemical sensors.

Large interlayer spacing Nb4C3Tx (MXene) promotes the ultrasensitive electrochemical detection of Pb2+ on glassy carbon electrodes  相似文献   
78.

Introduction

Malignant Pleural Effusion (MPE) is a common terminal clinical problem in patients with advance cancer. Treatment options for MPE include observation, thoracocentesis, or pleurodesis. In the current study, we compared the effectiveness and safety of combined mechanical and chemical pleurodesis by Video Assisted Thoracoscopic Surgery (VATS) with chemical pleurodesis via intercostals tube alone, using talc as pleurodesis agent in both.

Material and methods

In this prospective study, diagnosed patients of MPE having Eastern Cooperative Oncology Group (ECOG) performance score 3 or less 3, expected life expectancy of more than 3 months, and having lung re-expansion after drainage were selected for pleurodesis. Patients with ability to undergo general anesthesia were considered for VATS assisted combined mechanical & chemical pleurodesis (Group A). In the remaining chemical pleurodesis was performed at bedside (Group B).

Results

The duration of this study was 1 year. The total number of patients was 30. There were 15 patients each in both the groups. Pleurodesis was achieved in 4.47?±?0.92 days in group A and 6.33?±?0.90 days in group B. This difference was highly significant (p?<?0.0001). Post procedural complaints were more or less same in both the groups.

Conclusion

Combined mechanical and chemical pleurodesis (VATS assisted) appears to be superior to chemical pleurodesis, as it offers less morbidity, lesser hospital stay, and complete response in follow up. This modality may be used in patients of MPE for palliation, who are fit for general/ regional anesthesia.  相似文献   
79.
BackgroundBone fracture treatment usually involves restoring of the fractured parts to their initial position and immobilizing them until the healing takes place. Drilling of bone is common to produce hole for screw insertion to fix the fractured parts for immobilization. Orthopaedic drilling during surgical process causes increase in the bone temperature and forces which can cause osteonecrosis reducing the stability and strength of the fixation.MethodsA comprehensive review of all the relevant investigations carried on bone drilling is conducted. The experimental method used, results obtained and the conclusions made by the various researchers are described and compared.ResultReview suggests that the further improvement in the area of bone drilling is possible. The systematic review identified several consequential factors (drilling parameters and drill specifications) affecting bone drilling on which there no general agreement among investigators or are not adequately evaluated. These factors are highlighted and use of more advanced methods of drilling is accentuated. The use of more precise experimental set up which resembles the actual situation and the development of automated bone drilling system to minimize human error is addressed.ConclusionIn this review, an attempt has been made to systematically organize the research investigations conducted on bone drilling. Methods of treatment of bone fracture, studies on the determination of the threshold for thermal osteonecrosis, studies on the parameters influencing bone drilling and methods of the temperature measurement used are reviewed and the future work for the further improvement of bone drilling process is highlighted.  相似文献   
80.
Abstract

A rare case of cervical extradural en-plaquc méningothélial meningioma is reported. The magnetic resonance imaging revealed an extradural sheet of tumor encasing the cervical cord from anterior, posterior and right lateral aspects and emerging from the right C3–A intervertebral foramina. Though a differential diagnosis of lymphoma and tubercular granulation tissue were considered, its isointense intensity patterns on T1 and T2 weighted images and the intratumoral calcification on intrathecal contrast computed tomographic scan suggested a meningioma. At surgery, the lesion was fibrous, avascular and densely adherent to the dura. The radiological features and management options of the lesion are discussed. [Neurol Res 2000; 22: 351-353]  相似文献   
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