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61.
A 12-year-old girl presented with hemoptysis, fever and weight loss. She was initially diagnosed and treated for presumed tuberculosis and a lung abscess. Salmonella typhi was isolated from the abscess. Hydatid cyst was diagnosed at surgery. This is the first reported case of a pulmonary hydatid cyst infected with S. typhi.  相似文献   
62.
The purpose of this study was to investigate the image quality of coronary artery bypass graft visualization in 4- and 16-row multidetector CT using multiple imaging reformations. Material and Methods: One hundred sixteen patients underwent CT examination of the heart after receiving CABG. Group A (n=58) received 4-row MDCT; group B (n=58) received 16-row MDCT. Various bypass types such as LITA to LAD and venous grafts to the RCA and RCX were included in the study. A five-point Likert scale was used to grade image quality. Each bypass was reviewed under different imaging reformations: thin slap maximum intensity projection (MIP thin), multiplanar reformation (MPR) and volume rendering technique (VRT). Special attention was paid to the delineation of the distal anastomosis. Interobserver correlation was determined. Results: From 289 bypass grafts examined, 279 (96.54%) were classified as patent and 10 (3.46%) as not patent. Except for the distal anastomosis, 16-row MDCT showed significantly better results for all segments of bypasses. Comparison of reformations within group A and B showed that MIP thin (P<0.05) and VRT (P<0.05) displayed better visualization as compared to MPR. Conclusion: Significantly better imaging of all bypass types is possible using 16-row MDCT as compared to 4-row MDCT. Assessment of the distal anastomosis yields no difference between 4- and 16-row technology.This revised version was published online in October 2004 with a correction to the article title.  相似文献   
63.
64.
Anticipation is the term given to the apparent occurrence of an inherited disorder at a progressively earlier age of onset in successive generations. A family of a mother and two children, a 17-year-old girl and a 13-year-old boy, all experienced migraine with affective psychosis. There is a strong genetic predisposition to the psychiatric disorder of affective psychosis along with a dominant pattern of migraine in the family, which suggests a genetic connection between migraine and affective psychosis.  相似文献   
65.
Seven patients with colorectal adenocarcinoma and one with squamous cell carcinoma of anorectal region were infused preoperatively with iododeoxyuridine (IUdR) and bromodeoxyuridine (BrdU) in sequence (100 mg/m2 x 1 hr each with 1-hr interval in between) to label S-phase cells. The tumor biopsy specimens were embedded in glycol-methacrylate and 2-microns thick sections were treated with two monoclonal antibodies which permitted the identification of cells which incorporated IUdR only, BrdU only, both IUdR and BrdU, or neither IUdR or BrdU. The labeling index of tumors varied from 17.3 to 35.6% (mean = 25.78 +/- 6.162), duration of S-phase ranged from 14.0 to 23.9 hr (mean = 18.73 +/- 3.712), and total cell cycle time ranged from 39.4 to 123.4 hr (mean = 76.78 +/- 24.165). The architecture of the tumor was well preserved and a variable number of DNA synthesizing mononuclear cells were identified within and around the tumor. Image analysis of Feulgen-stained smears of the tumors was done to measure the DNA content of seven tumor samples. Each tumor was found to be hyperdiploid with multiple modal values. The studies described here demonstrate the feasibility of performing cell cycle kinetic measurements on gastrointestinal tumors which have been labeled in vivo. The ability to perform these measurements on tumor biopsies allows the avoidance of artifacts introduced when solid tumors are disaggregated in vitro for study.  相似文献   
66.
Neurons in the cerebellar cortex of camels were studied using modified Golgi impregnation methods. Neurons were classified according to their position, morphology of their soma, density and distribution of dendrites, and the course of their axons. Accordingly, eight types of neurons were identified. Three types were found in the molecular layer: upper and lower stellate cells and basket cells, and four types were found in the granular layer: granule cells, Golgi Type II cells, Lugaro cells, and unipolar brush cells. Only the somata of Purkinje cells were found in the Purkinje cell layer. The molecular layer is characterized by the presence of more dendrites, dendritic spines, and transverse fibers. Golgi cells also show extensive dendritic branching and spines. The results illustrate the neuronal features of the camel cerebellum as a large mammal living in harsh environmental conditions. These findings should contribute to advancing our understanding of species-comparative anatomy in achieving better coordination of motor activity.  相似文献   
67.
The pathophysiology of allergic rhinitis and its drug treatment is reviewed. Special emphasis is placed upon potential new treatments. Allergic rhinitis is characterized by allergen(s), symptoms (sneezing, itching, rhinorrhea, nasal congestion and nasal hypersensitivity), and signs such as invasion of nasal mucosa by inflammatory cells. Such pathological changes are due to inflammatory responses mediated by way of allergen-immunoglobulin E (IgE)-cell complex formation. The complexity of the disease and the multiple pathways involved offer many targets for drug treatment, but to date no single drug is totally effective. This review summarizes the current knowledge of allergic rhinitis, its prevalence, pathophysiology and experimental and clinical treatments. In the search for new drugs, different experimental animal models of allergic rhinitis are required. As a result the models have also been reviewed. Furthermore, particular aspects of the pathophysiology of allergic rhinitis are discussed in greater detail including the immune cells involved in the mediation of the disease, chemical mediators, their actions, and the receptors on which they act. Therapy, particularly that with current drugs, targets many of the known mediators and some of the cellular processes with varying success. Other drugs, for example, vasoconstrictors given to reduce rhinorrhea, provide symptomatic relief by counteracting symptoms. Since the incidence of allergic rhinitis is prevalent and growing in many parts of the world and current treatments are not ideal, it is important to continue to study the pharmacology of this disease as part of a search for better drugs.  相似文献   
68.
Primary health care in Saudi Arabia: applying global aspects of health for all, locally This paper describes the application of primary health care principles in the Islamic Kingdom of Saudi Arabia. It arose from a doctoral supervisory experience on a joint programme for women students, operating between a British and Saudi Arabian University. The research looked at nutritional advice given by diploma-level nurses to pregnant women attending primary health care centres in Saudi Arabia. The supervisor supported research that drew on internationally recognized trends in nursing research (the reflexive learner) whilst attending to local requirements and conventions of the culture. The student was encouraged explicitly to site the research within the framework of Islamic teaching and Saudi culture. The Qur'an was used as an overarching framework within which the tenets of primary health care were explored. This was seen to be crucial in addressing World Health Organisation and the International Council of Nurses' views on contextualizing nursing for the greatest benefit of the population. This was of particular relevance in Saudi Arabia where research carried out in the community by women is novel, and as yet there are no nurse theorists from within Saudi culture.  相似文献   
69.
Acanthamoeba keratitis is a serious infection with blinding consequences and often associated with contact lens wear. Early diagnosis, followed by aggressive topical application of drugs, is a prerequisite in successful treatment, but even then prognosis remains poor. Several drugs have shown promise, including chlorhexidine gluconate; however, host cell toxicity at physiologically relevant concentrations remains a challenge. Nanoparticles, subcolloidal structures ranging in size from 10 to 100 nm, are effective drug carriers for enhancing drug potency. The overall aim of the present study was to determine whether conjugation with gold nanoparticles enhances the antiacanthamoebic potential of chlorhexidine. Gold-conjugated chlorhexidine nanoparticles were synthesized. Briefly, gold solution was mixed with chlorhexidine and reduced by adding sodium borohydride, resulting in an intense deep red color, indicative of colloidal gold-conjugated chlorhexidine nanoparticles. The synthesis was confirmed using UV-visible spectrophotometry that shows a plasmon resonance peak of 500 to 550 nm, indicative of gold nanoparticles. Further characterization using matrix-assisted laser desorption ionization-mass spectrometry showed a gold-conjugated chlorhexidine complex at m/z 699 ranging in size from 20 to 100 nm, as determined using atomic force microscopy. To determine the amoebicidal and amoebistatic effects, amoebae were incubated with gold-conjugated chlorhexidine nanoparticles. For controls, amoebae also were incubated with gold and silver nanoparticles alone, chlorhexidine alone, neomycin-conjugated nanoparticles, and neomycin alone. The findings showed that gold-conjugated chlorhexidine nanoparticles exhibited significant amoebicidal and amoebistatic effects at 5 μM. Amoebicidal effects were observed by parasite viability testing using a Trypan blue exclusion assay and flow-cytometric analysis using propidium iodide, while amoebistatic effects were observed using growth assays. In contrast, chlorhexidine alone, at a similar concentration, showed limited effects. Notably, neomycin alone or conjugated with nanoparticles did not show amoebicidal or amoebistatic effects. Pretreatment of A. castellanii with gold-conjugated chlorhexidine nanoparticles reduced amoeba-mediated host cell cytotoxicity from 90% to 40% at 5 μM. In contrast, chlorhexidine alone, at similar concentrations, had no protective effects for the host cells. Similarly, amoebae treated with neomycin alone or neomycin-conjugated nanoparticles showed no protective effects. Overall, these findings suggest that gold-conjugated chlorhexidine nanoparticles hold promise in the improved treatment of A. castellanii keratitis.  相似文献   
70.
Dichlorvos [2,2-dichlorovinyl dimethyl phosphate] is one of the most common in-use organophosphate (OP) in developing nations. Previous studies from our lab have shown chronic Dichlorvos exposure leads to neuronal cell death in rats. However, the extent of damage caused by Dichlorvos to other cells of the central nervous system (CNS) is still not clear. Microglial cells are the primary threat sensors of CNS which become activated in many pathological conditions. Activation of microglial cells results in reactive microgliosis, manifested by increased cellular damage in the affected regions. Using rat primary microglial cultures, here we show that Dichlorvos exposure can activate and induce apoptotic cell death in microglia. We observed significant up-regulation of pro-inflammatory molecules like nitric oxide, TNF-α, and IL-1β when microglia were treated with Dichlorvos (10 μM). Significant up-regulation of CD11b, microglial specific activation marker, was also observed after 24 h of Dichlorvos treatment. The activated microglial cells eventually undergo cell death after 48 h of Dichlorvos treatment. The DNA fragmentation pattern of Dichlorvos treated microglia along with increased expression of Bax in mitochondria, cytochrome c release from mitochondria, and caspase-3 activation led us to assume that microglia were undergoing apoptosis. Thus, the present study showed that Dichlorvos can induce microglial activation and ultimately apoptotic cell death. These findings gave new perspective to the current knowledge of Dichlorvos (OPs) mediated CNS damage and presents microglial activation as a potential therapeutic target for preventing the OP induced neuronal damage.  相似文献   
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