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101.
Dichlorvos in a special slow release formulation at 31 mg/kg body mass in equines was highly effective against all adult strongyles and Oxyuris equi, Parascaris equorum, Probstmayria vivipara and bots of Gasterophilus spp. It has no effect on 4th stage larvae of Trichonema ssp. nor the stomach worms Draschia megastoma and Habronema spp. Doses of dichlorovos 10 and 20 times the therapeutic dose (310 and 620 mg/kg body mass) caused transient clinical signs but these disappeared 96 hours after dosing.  相似文献   
102.
Adjuvants--a balance between toxicity and adjuvanticity   总被引:1,自引:0,他引:1  
Adjuvants have been used to augment the immune response in experimental immunology as well as in practical vaccination for more than 60 years. The chemical nature of adjuvants, their mode of action and the profile of their side effects are highly variable. Some of the side effects can be ascribed to an unintentional stimulation of different mechanisms of the immune system whereas others may reflect general adverse pharmacological reactions. The most common adjuvants for human use today are still aluminium hydroxide, aluminium phosphate and calcium phosphate although oil emulsions, products from bacteria and their synthetic derivatives as well as liposomes have also been tested or used in humans. In recent years monophosphoryl lipid A, ISCOMs with Quil-A and Syntex adjuvant formulation (SAF) containing the threonyl derivative of muramyl dipeptide have been under consideration for use as adjuvants in humans. At present the choice of adjuvants for human vaccination reflects a compromise between a requirement for adjuvanticity and an acceptable low level of side effects.  相似文献   
103.
Rate of reduction of ferric oxide in the presence of solid carbon was measured in the laboratory using a thermogravimetry setup. Iron oxide in the form of powder and micropellets were used. Coconut char of high reactivity was employed as carbonaceous material. Product gas analysis was carried out to calculate the rate of carbon loss during reduction. Ferric oxide reduction was found to take place in a stage-wise manner. For the powder system, the overall reaction was found to be exclusively controlled by the gasification process. Gasification rates of coconut char in carbon dioxide were utilized to predict the rates of carbon loss during reduction. The predicted and experimental rates of carbon loss during reduction of ferric oxide by carbon were compared and possible explanations were given for the observed trends.  相似文献   
104.
An adult female Oustalet's chameleon was examined to determine the cause of a fluctuant enlargement of the right superior eyelid. Surgical exploration of the subcutaneous tissues of the eyelid revealed live microfilarial parasites, which were identified later as Foleyella sp. These parasites, although seldomly reported, are fairly common in imported chameleons and can be detected during examination of blood smears. Surgical removal continues to be the treatment of choice for these parasites, because the efficacy and safety of many new anthelmintic agents have not been determined for use in chameleons.  相似文献   
105.
About 20% of all women with insulin-dependent diabetes mellitus (IDDM) have menstrual irregularities. Eight percent have amenorrhea. Fluctuations in blood glucose and insulin concentration are probably contributing factors, but the irregular menstrual cycles are mainly caused by disorders in the central ovulatory mechanisms. Hypothalamic GnRH release is regulated by several neuropeptides. Dopamine and opiates exert an inhibitory effect, and there is evidence for an abnormally high dopaminergic hypothalamic activity among women with IDDM. There might also be disorders of the opioid, serotonergic and GABA'ergic systems, but the consequences of there possibilities remain uncertain.  相似文献   
106.
A 45-year-old woman was incidentally suspected to have megacolon. Chest X-rays showed elevated left diaphragm due to colonic gas, and the heart was deviated to the midline. Barium enema revealed marked dilation of the sigmoid colon, confirming the diagnosis of megacolon. Maximal diameter of the sigmoid colon was 23 cm, but she had no gastrointestinal symptoms. During the work up for megacolon, the presence of myotonic dystrophy was suspected. She had hatchet face, but was not bald. Muscles of the neck and extremities were slightly atrophic. There was percussion myotonia of the tongue and both hands, and grip myotonia of the hands. Laboratory examinations showed impaired glucose tolerance and low level of serum IgG. EMG showed myotonic discharges and myopathic units in the limbs. Brain CT imaging revealed a thick skull. Cases of myotonic dystrophy associated with marked megacolon are rare in Japan. Megacolon presents a high risk for ileus, volvulus, and rupture, and myotonic dystrophy is associated with a high operative and anesthesic risk. Megacolon, therefore, is an important complication to look for in the management of myotonic dystrophy.  相似文献   
107.
RPE65 is a potential retinoid-processing protein expressed in the retinal pigment epithelium. Mutations in the RPE65 gene have been shown to cause certain inherited retinal dystrophies. Previous studies have shown that salamander cone photoreceptor cells have a unique retinoid processing mechanism which is distinct from that of rods. To determine whether RPE65 is expressed in photoreceptors, the RPE65 cDNA was cloned from a salamander retinal cDNA library. The deduced protein consists of 533 amino acids and is 85% identical to human and bovine RPE65. The RPE65 mRNA was detected in all of the single cone cells isolated from the salamander retina, as well as in the retinal pigment epithelium by RT-PCR, but not in the isolated rods. The RT-PCR products have been confirmed to be RPE65 by DNA sequencing. The results indicate that this potential retinoid processing protein is expressed in the cone photoreceptor cells but not in rods. Therefore, this protein may contribute to the unique retinoid processing capabilities in salamander cones.  相似文献   
108.
By designing recombinant genes containing tandem copies of the coding region of the BHLH domain of MASH-1 (MASH-BHLH) with intervening DNA sequences encoding linker sequences of 8 or 17 amino acids, the two subunits of the MASH dimer have been connected to form the single chain dimers MM8 and MM17. Despite the long and flexible linkers which connect the C-terminus of the first BHLH subunit to the N-terminus of the second, a distance of approximately 55 A, the single chain dimers could be produced in Escherichia coli at high levels. MM8 and MM17 were monomeric and no 'cross-folding' of the subunits was observed. CD spectroscopy revealed that, like wild-type MASH-BHLH, MM8 and MM17 adopt only partly folded structures in the absence of DNA, but undergo a folding transition to a mainly alpha-helical conformation on DNA binding. Titrations by electrophoretic mobility shift assays revealed that the affinity of the single chain dimers for E box-containing DNA sequences was increased approximately 10-fold when compared with wild-type MASH-BHLH. On the other hand, the affinity for heterologous DNA sequences was increased only 5-fold. Therefore, the introduction of the peptide linker led to a 4-fold increase in DNA binding specificity from -0.14 to -0.57 kcal/mol.  相似文献   
109.
OBJECTIVES: The purpose of this study was to design a multidimensional measure of health-related quality of life appropriate for patients with cardiovascular disease that was psychometrically sound, brief, and easy to administer. METHODS: Qualitative interviews conducted with healthy subjects and patients with cardiovascular diseases identified nine major quality of life domains. Based on the responses of 129 cardiovascular disease patients recruited from hospitals and clinics, a criterion-based approach was used to select 35 questionnaire items that best tapped these domains. Psychometric properties of the Multidimensional Index of Life Quality (MILQ) were tested with a sample of 348 patients with various cardiovascular diseases. RESULTS: Cronbach's alpha was 0.76 or higher for eight of the nine MILQ domains. Test-retest reliability coefficients were 0.73 or greater in all but two domains. Individual domain scores as well as a weighted overall quality of life index were correlated highly with self-assessed health and the number of heart-related symptoms. CONCLUSIONS: The Multidimensional Index of Life Quality is a psychometrically reliable and valid instrument for measuring quality of life in patients with cardiovascular diseases. The MILQ also may be a suitable measure for other types of chronic diseases.  相似文献   
110.
Intracellular localization studies of various potyvirus proteins have been made in hope of finding clues to their function(s). Immunocytological studies localized many of the tobacco etch virus (TEV)-encoded proteins in infected cells. We used antiserum against the nonstructural P3 protein of TEV to determine the subcellular location of the P3 protein in ultrathin sections of virus-infected cells. Immunogold labeling with the antiserum showed labels associated with nucleoli, nuclei, or NIs, Absorption of antiserum with purified NIs or P3 protein resulted in no labeling. TEV NIs are known to contain a bifunctional genome-linked protein-viral proteinase (NIa-VPg) and RNA-dependent RNA polymerase (NIb). It appeared that the TEV P3 protein was a third nonstructural viral protein of NIs of TEV if the NIa-VPg is considered one protein. The presence of P3 in NIs was also supported by Western blot assays. P3 protein in the nucleolus and nucleus could indicate that it, too, is involved in early stages of viral replication.  相似文献   
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