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1.
The glucose deprivation-induced release of [3H]D-aspartate was studied in bovine and human retinas in a superfusion apparatus. [3H]D-aspartate release was significantly increased upon omitting glucose in the superfusion buffer. This effect was dependent on external Ca2+ because L- and N-type Ca2+-channel blockers, such as diltiazem (1 microM), nitrendipine (1 microM), and omega-conotoxin (100 nM), significantly reduced the effect of glucose-deprivation induced release of [3H]D-aspartate. Furthermore, while glutamate receptor agonists (L-glutamate, N-methyl-D-aspartate, but not kainate) potentiated the effects of glucose deprivation, antagonists (MK-801, MCPG, ifenprodil, and L-AP3) at these receptors blocked the glucose deprivation-induced release process. Taken together, these studies have demonstrated that under conditions of glucose deprivation, as may happen during ischemic events in vivo, the retinal glutamatergic nerve endings and/or glial cells promote the efflux of [3H]D-aspartate into the extracellular environment. This process appears to be receptor-mediated and dependent on extracellular Ca2+ and is similar to previous reports pertaining to brain tissues.  相似文献   
2.
The purpose of this study was to determine the prevalence, course, and risk factors for executive impairment in patients hospitalized on a general medicine service. One hundred patients were administered the Executive Interview (EXIT25), the Executive Clock Drawing Task (CLOX), and the Mini-Mental State Examination at admission and discharge. Fifty-two percent of the patients at admission and 56% at discharge had scores indicating impairment on at least one measure of executive function. Median scores on every measure improved during hospitalization. Older patients and those with a cardiac or gastrointestinal disorder were more likely to have executive impairment. The prevalence of executive impairment on general medicine services is high. Although improvement in executive function occurs during hospitalization, many patients remained impaired.  相似文献   
3.
Bounds in the Sensitivity of BioMEMS Devices for Cell Detection   总被引:2,自引:0,他引:2  
This paper presents an ongoing effort to characterize performance and reliability of micro electromechanical systems used for biomedical diagnostics (BioMEMS). In order to study the interactions of human osteosarcoma (HOS) cells with BioMEMS devices, cultures were performed on silicon (Si) surfaces as well as silicon surfaces coated with 50 nm of titanium (Ti). Cell spreading on the surfaces was observed over time for up to 2 hours. It was seen that titanium coated silicon surfaces have the potential to provide a better interface for BioMEMS devices, due to enhanced adherence and spreading of the cells on these surfaces. Atomic force microscope (AFM) cantilevers were used as cell detection sensors. These cantilevers were coated with 50nm of titanium metal to provide a cell friendly surface. Theoretical models were then developed for the prediction of the vibrational responses of the AFM cantilevers before and after cell attachment. The models were used to relate the experimentally observed changes in frequency to the number of cells that are attached on the cantilever. The bounds in the possible frequency changes were determined within a theoretical framework. From experimentally calculated values for the mass of cells, random number simulations were carried out to determine the probability of cell attachment as a function of the change in resonance frequency of the cantilever sensor. The implications of the results are then discussed for the future reliability modeling of the sensor.  相似文献   
4.
The incidence of cervical spine injury in patients with polytrauma is 3.7%. Early identification and management of cervical spine injuries in these patients play a crucial role in preventing secondary cervical spine and cord injuries. C-spine clearance assumes a pivotal role in reducing the morbidity and mortality associated with cervical spine injury. Despite the availability of various validated management algorithms and protocols for C-spine clearance, there are several controversies regarding C-spine clearance, such as the ideal protocol and imaging modality, clearance of obtunded patients and management of patients that lie out of the described protocols and rules. The current article aims to provide a comprehensive review of the relevant literature and address the prevalent controversies.  相似文献   
5.
BackgroundInjuries involving upper cervical spine are serious and fatal injuries which are associated with alteration of normal occipital–cervical anatomy. These injuries may result in permanent neurologic deficits or neck deformity if not treated in a timely and appropriate manner.ObjectiveTo evaluate the outcomes of neglected upper cervical spine injuries treated by various methods.Study designRetrospective study.Materials and methodsTwelve patients attending ER or OPD with a history of neck trauma and who were diagnosed with fractures and fracture dislocations C1 and C2 were included in the study. Fresh injuries sustained within a week were excluded from study. The outcomes were measured in terms of improvement in VAS, ODI Scores and correction of the neck deformity. Surgical parameters like duration of surgery and blood loss were also observed.ResultsEleven males and one female. The mean age was 40.9 ± 16.9 (07–67 years). Eleven patients underwent posterior instrumentation, while one patient was treated anteriorly. The mean delay in presentation was 28 ± 8.67 days (15–42 days). The mean duration of surgery was 188.3 ± 34.35 min (120–240 min), average blood loss was 350 ± 111.8 ml (150–600 ml). The mean VAS improved from 8.45 ± 0.89 to 3.9 ± 0.51 (p < 0.05). The mean ODI Pre-operatively was 88.45 ± 5.89 which improved to 31.9 ± 4.01 (p < 0.05). The neck deformity/torticollis was corrected in all the patients.ConclusionsNeglected upper cervical spine injuries are difficult to treat and a posterior approach is helpful in reducing the subluxations indirectly and to obtain a posterior fusion.  相似文献   
6.
Hydatid cyst is a cyclozoonotic infection of the larvae form of a platyhelminthes Echinococcus granulosus. The majority of hydatid cysts appear in the liver (65%) and lungs (25%). Kidneys and brain are other less common sites for this disease. Only 1% to 2% cases are seen in the maxillofacial region. These commonly appear as cystic lesions located in the mandible, maxillary sinus, orbit, infratemporal fossa, pterygopalatine fossa, parapharyngeal space, tongue, and parotid and submandibular salivary gland. Hydatid cysts of the orbit are rare and account for 1% of all hydatid cysts. The article presents hydatid cyst of the orbit in a 10-year-old child. Clinical features, investigations, surgical approaches, and adjuvant medical management have been emphasized. We believe that the lateral orbital route allows excellent exposure and safe removal of an intraorbital hydatid cyst located posteriorly, superiorly, and laterally without damaging the surrounding important orbital structures. Upper blepharoplasty incision results in good cosmetic outcome.  相似文献   
7.
Hyperdontia or supernumerary teeth without associated syndrome is a rare phenomenon, as supernumerary teeth are usually associated with cleft lip and palate or other syndromes such as Gardner's syndrome, cleidocranial dysplasia, and so on. Five patients with supernumerary teeth visited our department. They had no familial history or other pathology, certain treatment protocols was modified due to the presence of supernumerary teeth. Non-syndromic supernumerary teeth, if asymptomatic, need to have periodical radiographic observation. If they showed no variation as they impacted in the jaw, careful examination is necessary because they may develop into pathological status such as dentigerous cysts. The importance of a precise clinical history and radiographic examination for patients with multiple supernumerary teeth should be emphasized.  相似文献   
8.
In recent years, AIDS and sexually transmitted diseases (STDs) have become a burgeoning problem and are spreading at an alarming rate. Microbicides are being developed as a new therapeutic category for prevention of transmission of sexually transmitted infections (STIs) and HIV. Many of the microbicide formulations (MF) may fail to elicit a protective response either because of a lack of efficacy or inadequate formulation. Manufacturing a stable, efficacious, safe, and optimal product is the main objective of formulation development programs. Preformulation parameters (PP), as discussed in Part I of this series, influence formulation development significantly and should be considered carefully before designing a formulation strategy. Initially, based on PP and market research, a target product profile (TPP) is generated, which defines product attributes that can be normally classified as "essential" and "desirable." A complex and dynamic process begins thereafter that takes into consideration myriad factors starting from selection of delivery system, selection of excipients, compatibility study, prototype composition, selection of process and optimization, stability testing, scale up, manufacturing under good manufacturing practices (GMP), and packaging development. Prototype formulations are evaluated for several performance characteristics (e.g., dispersion behavior, bioadhesion, retention, spreading, rheology). These compositions are also subjected to biologic evaluation by various in vitro and in vivo models. Such a well-planned, well-coordinated, and well-implemented formulation development program not only accelerates overall development but also minimizes failures in subsequent clinical development studies. The objective of this review is to highlight the importance of formulation science, outline the steps involved in this process, and explore how these can be exploited for achieving optimal MF.  相似文献   
9.

Purpose of review

Primary central nervous system angiitis (PCNSA) is a rare disease. Varying clinical pictures coupled with lack of sensitive and specific diagnostic tests lead to challenges in management of these patients. This unfortunately may lead to both under- or over-diagnosis and unnecessary treatment. It is important to recognize the different conditions that may mimic the clinical and radiologic presentation. We present a contemporary literature review that should update physicians who encounter this patient population.

Recent findings

Recent additions to the literature in form of case reports and single-center series show that digital subtraction angiography was the most widely used test to diagnose PCNSA. It is also important to note that brain biopsy is still considered “gold standard” and should be pursued as it not only has information that establishes the diagnosis but also may help in ruling out the diagnosis from mimics. In around 39% of suspected cases, an alternate diagnosis was eventually confirmed highlighting the importance of a comprehensive work-up. For treatment, almost all the literature supports the use of glucocorticoids as the initial treatment and if the patient has a relapse or develops steroid toxicity then the second most commonly used agent was cyclophosphamide. There are increasing reports of benefits with other agents such as methotrexate, azathioprine, mycophenolate, infliximab, and etanercept.

Summary

The diagnosis and management of PCNSA continues to be a challenge. Formation of prospective patient registries with continued immunologic research for novel targets and immunomodulatory modalities may hold promise for future care of these patients.
  相似文献   
10.
The results of a multi-surgeon, multi-implant series of patellofemoral joint arthroplasties performed over a ten year period are presented. All patellofemoral joint arthroplasties performed from 1997 to 2006 were retrospectively reviewed using case notes, radiographs and clinic appointments until their latest follow-up period. One hundred and one arthroplasties in 91 patients were followed up for an average period of 48 months (range 6-96 months). The average age was 57 years with female patients thrice as common as male patients. There were 5 (5%) complications with 1 deep infection and 4 stiff knees. Thirty five subsequent procedures were performed in 28 patients including arthroscopic debridement in 18, arthroscopic lateral retinacular release in 8, tibial tuberosity transfer in 3, manipulation for stiffness in 2, and revision to total knee arthroplasty in 4 patients (3 for progression of tibiofemoral osteoarthritis and 1 for infection). The necessity of further surgeries in one third of the study group suggests that close follow-up of these patients is needed to address any concerns that can be easily resolved.  相似文献   
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