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1.
Monoclonal antibodies against the myosin heavy chain of Amoeba proteus were obtained and used to localize myosin inside amoebae and to clone cDNAs encoding myosin. Myosin was found throughout the amoeba cytoplasm but was more concentrated in the ectoplasmic regions as determined by indirect immunofluorescence microscopy. In symbiont-bearing xD amoebae, myosin was also found on the symbiosome membranes, as checked by indirect immunofluorescence microscopy and by immunoelectron microscopy. The open reading frame of a cloned myosin cDNA contained 6,414 nucleotides, coding for a polypeptide of 2,138 amino acids. While the amino-acid sequence of the globular head region of amoeba's myosin had a high degree of similarity with that of myosins from various organisms, the tail region building a coiled-coil structure did not show a significant sequence similarity. There appeared to be at least three different isoforms of myosins in amoebae, with closely related amino acids in the globular head region.  相似文献   

2.
The aims of treating patients with asthma are to relieve symptoms, to prevent symptoms and exacerbations, and to prevent long-term deterioration in lung function. It is the role of medical practitioners to inform the patient what asthma is, and to develop a plan to achieve the aims for the individual, recognizing that asthma is frequently a chronic, lifelong disease. Most patients can be diagnosed, assessed for severity and causes, and treated in primary care practices, however, sometimes help from an asthma clinic of a specialist is required. The most important management decision is to determine whether the patient needs inhaled corticosteroids; subsequently, decisions about dose, duration and method of delivery of treatment can be tailored to the individual depending on the preferences and social conditions of the patient. The aim of this article is to present the latest strategies for the management of asthma and the simplest methods for their implementation. Important new strategies include careful assessment of the severity; immediate introduction of a plan that is tailored of the individual and aimed at the possible reversing of the disease; detailed instructions for management of exacerbations and the combined use of inhaled corticosteroids with a long-acting bronchodilator. It is becoming clear that these strategies obviate dependence on oral corticosteroids in newly diagnosed asthmatic patients. Furthermore, relatively low doses of inhaled corticosteroids can be used to maintain good control if used in conjunction with other therapies. The role of newly developed antagonists to leukotrienes is not yet known but it may well be useful in mild asthma and in special forms of the disease, such as those sensitive to aspirin. In the future, the most important strategy will be to prevent the disease.  相似文献   

3.
Aseptic barriers are employed in the form of surgical gowns, drapes, and wrappers for sterile goods. They possess many of the attributes of textiles, but must also protect sterile zones from microbial invasion. Surgeons rely on them to resist penetration by liquids and other bacterial vehicles. A large variety of both woven and nonwoven materials are being produced for this purpose. The user is faced with difficult choices. The provider of the barrier materials must assure the surgeon of their barrier quality under the usual conditions of their use in operating rooms. Identical standards of quality can be and should be applicable whether these materials are created to be used once and discarded or are reusable.  相似文献   

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A retrospective study on the different opening techniques in cataract surgery at our Department in 1996 was carried out. In our everyday practice fornix based conjunctival flap and sclerocorneal oblique or vertical-oblique approach with a center at 12 o'clock was performed. In the case of hemorrhagic diathesis and secondary ACL implantation the corneal approach was preferred. After glaucomatous filtration surgery the incision was made temporally in some cases.  相似文献   

6.
A rapid assessment of drug abuse in Nepal was conducted at different sites, including eight municipalities in the five development regions of the country. To interview various groups of key informants, such methods as semi-structured interviews, in-depth interviews and focus group discussions were used. A snowball sampling strategy for respondents who were drug abusers and a judgemental sampling strategy for the non-drug-using key informants were applied. About one fifth of the sample was recruited from the treatment centres and the rest from the community. Drug abusers in prison were interviewed, and secondary data from treatment centres and prisons analysed. The study revealed that the sample of drug abusers had a mean age of 23.8 years and was overwhelmingly male. Most respondents lived with their families and were either unemployed or students. About 30 per cent of the sample was married. A large majority of the sample had a family member or a close relative outside the immediate family who smoked or drank alcohol and a friend who smoked, drank or used illicit drugs. Apart from tobacco and alcohol, the major drugs of abuse were cannabis, codeine-containing cough syrup, nitrazepam tablets, buprenor-phine injections and heroin (usually smoked, rarely injected). The commonest sources of drugs were other drug-using friends, cross-border supplies from India or medicine shops. The commonest source of drug money was the family. There has been a clear trend towards the injection of buprenorphine by abusers who smoke heroin or drink codeine cough syrup. The reasons cited for switching to injections were the unavailability and rising cost of non-injectable drugs and the easy availability and relative cheapness of injectables. About a half of the injecting drug users (IDUs) commonly reported sharing injecting equipment inadequately cleaned with water. Over a half of IDUs reported visiting needle-exchange programmes at two of the study sites where such programmes were available. Infection by the human immunodeficiency virus (HIV) appears to be low among IDUs, although systematic surveillance is absent. Two thirds of the sample had experienced sexual intercourse. The last sex partners reported by respondents were commercial sex workers, wives or girl friends. Condom use was low with primary partners and relatively high with sex workers. Treatment facilities, mostly located in the central urban areas of the country, are meagre. An overwhelming majority of drug abusers felt the need to stop abusing drugs. Cost-effective drug treatment and HIV prevention programmes for IDUs are urgently needed in all areas of the country.  相似文献   

7.
Tight junctions (TJs) are essential structures for the physiological functions of epithelial and endothelial cells, and have been suggested to have both barrier and fence functions. Tight junctions create a primary barrier to the diffusion of solutes through the paracellular pathway, and also function as a fence between apical and basolateral membrane domains, to create and maintain cell polarity of epithelial and endothelial cells. Several peripheral membrane proteins have been shown to be concentrated at the cytoplasmic surface of TJs. However, TJ-specific integral membrane proteins had not been identified until recently, and the lack of information concerning TJ-specific integral membrane proteins has hampered a more direct assessment of the function of TJs at the molecular level. Here, we present an overview of current progress in the identification of TJ-specific integral membrane proteins.  相似文献   

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OBJECTIVE: This study aimed to investigate the relationship between postoperative endophthalmitis and current changes in the cataract operative technique. DESIGN: A retrospective case-control study. PARTICIPANTS: The 22,091 cataract operations performed from 1990 through 1993 at St Eriks Hospital formed the basis for this investigation. In a random fashion, 220 control subjects were selected to be compared with the endophthalmitis cases. MAIN OUTCOME MEASURES: Numerous variables pertaining to the cataract extraction procedure and to the ocular and general health of patients with cataracts were analyzed regarding the development of postoperative intraocular infection. Patient age, presence of diabetes or immunosuppression, type of cataract extraction and intraocular lens (IOL), and intraoperative or postoperative complications were the principal variables assessed. RESULTS: Fifty-seven patients with endophthalmitis were diagnosed, resulting in an overall frequency of 0.26%. Immunosuppressive treatment (P = 0.019), wound abnormality (P = 0.03), and the use of IOLs without a heparinized surface (P = 0.0023) were the only significant risk factors found in a logistic regression model. CONCLUSIONS: The results suggest that cataract operating practice may alter the risk for endophthalmitis in that implanting a heparinized IOL and creating a tight section both seem to provide protection against this dreaded complication. Regarding patient history, an increased susceptibility was found among subjects treated with immunosuppressants. Designing a prophylactic protocol that protects against endophthalmitis more efficiently than did the study prophylaxis of 20 mg of subconjunctival gentamicin, is important not only for this patient subgroup but also for the cataract operated population at large.  相似文献   

10.
The current accessibility and sophistication of hardware and software has made it possible to design high-quality data management systems for community-based trials in resource-poor environments. We designed, implemented, and operated an effective data management system for the Nepal Nutrition Intervention Project Sarlahi (NNIPS), a placebo-controlled community trial to assess the impact of vitamin A supplementation on the preschool mortality of 38,000 children in the Sarlahi district of Nepal. A data center was established in Kathmandu, approximately 8 hr drive from the study area. The trial is now completed and over 200,000 forms have been processed. The majority of potential data discrepancies were identified and corrected by field workers during the interviews. Supervisors and forms editors located at the field office corrected most data errors. Once forms reach Kathmandu, the average number of data entry errors was 3.1 per 10,000 keystrokes for the eight data entry operators employed during the study. Extensive computerized checking of data during data entry found out-of-range, missing, or inconsistent data in only 1% of forms. Timely analysis of field worker performance provided ongoing feedback to supervisors and analysis for the Data Safety and Monitoring Committee, and for publication of results.  相似文献   

11.
PURPOSE: To study the accuracy of predicting visual results after cataract surgery using a mathematical model of surgically induced refractive change and a previously published regression formula predicting uncorrected visual acuity as a function of the resulting spherocylinder. SETTING: Outpatient cataract clinic at a university hospital. METHODS: In this prospective study with a 4 month follow-up, 333 patients had phacoemulsification using a 6 or 4 mm scleral tunnel incision. Final refraction and uncorrected visual acuity were predicted based on preoperative and 1 day postoperative measurements, which were compared with the final visual results. RESULTS: A significant correlation was found between the observed and the predicted visual acuity in each eye (P < .01). CONCLUSION: The visual outcome of cataract extraction can be predicted from a theoretical model of the surgically induced refractive change.  相似文献   

12.
PURPOSE: To compare the use of topical anesthesia with that of peribulbar anesthesia in cataract surgery. SETTING: Quinze-Vingts Hospital, Paris, France. METHODS: This prospective study comprised 45 patients who had phacoemulsification and intraocular lens implantation in both eyes with 1 to 9 months between surgeries. Each patient had peribulbar anesthesia for one surgery and topical anesthesia for the other. The anesthesia method for the first eye was randomly selected. After surgery, patients were asked to rate their pain and whether they preferred one anesthesia technique over the other. RESULTS: When topical anesthesia was given, 82.2% of patients required no intravenous medications. Overall, 62.2% preferred topical over peribulbar anesthesia, with most patients citing the lack of periocular injection as the reason. CONCLUSION: Despite the increased technical difficulty, topical anesthesia proved an effective alternative to peribulbar anesthesia for cataract surgery that avoids the risks of periocular injection and reduces the need for intravenous medications.  相似文献   

13.
PURPOSE: To measure anterior capsule opening (ACO) size after acrylic intraocular lens (IOL) implantation and study the natural course of ACO reduction. SETTING: Kimura Eye and Internal Medicine Hospital, Hiroshima, Japan. METHODS: This study comprised 32 patients (38 eyes) having continuous curvilinear capsulorhexis, phacoemulsification, acrylic IOL implantation, and a self-sealing incision performed by 1 surgeon. A retroillumination photograph of the ACO was obtained with the Anterior Eye Segment Analysis System and converted to a computer image. The images were used to measure ACO size postoperatively and calculate the reduction ratio. Follow-up was 6 months. RESULTS: The postoperative reduction ratio in ACO size was 2.14% at 1 week, 3.83% at 1 month, 4.29% at 3 months, and 5.03% at 6 months. In a few cases, the reduction was progressively severe throughout the follow-up. CONCLUSIONS: The anterior capsule opening shrank rapidly during the first month after acrylic IOL implantation, followed by a slower progressive reduction in the subsequent 6 months. When severe, progressive shrinkage occurs, an anterior neodymium:YAG laser capsulotomy should be performed within 2 months postoperatively.  相似文献   

14.
A new thermodynamic model for calculating the dissociation constants of complexes formed between the aryl hydrocarbon receptor (AhR) and polychlorinated biphenyls (PCBs) is reported. The free energies of binding of PCBs to AhR are controlled by their lipophilicities, electron affinities, and entropies. The corresponding physicochemical properties of polychlorinated dibenzo-p-dioxins and dibenzofurans also control their interactions with AhR. We present evidence supporting the hypothesis that the majority of PCBs are likely to interact with AhR in their nonplanar conformations. In addition, we demonstrate that the affinities of PCBs for AhR relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin correlate with corresponding toxic equivalency factors in animals. The reported methodology is likely to be applicable to other polyhalogenated and mixed polyhalogenated bi- and terphenyls and related xenobiotics; thus, it could minimize the number of in vivo studies in laboratory animals and facilitate the identification of potentially hazardous aromatic xenobiotics.  相似文献   

15.
AIMS: This study investigated the effect of tissue plasminogen activator (tPA) in patients with severe intracameral fibrin after extracapsular cataract extraction or phacoemulsification with posterior chamber intraocular lens implantation. METHODS: A randomised prospective multicentre study was carried out in 86 patients with intraocular fibrin formation 2-8 days after cataract surgery. While the first group (n = 41) received only anti-inflammatory drugs, a single anterior chamber injection of tPA (10 micrograms) as an additional treatment to the standard was given in the second group (n = 44). On days 1, 2, 14, and 90 after randomisation, the visual acuities, slit lamp findings, and intraocular pressures were documented in standardised protocols. Efficacy of treatment was judged by the rate of fibrinolysis (primary objective), the frequency of synechiae, and central capsular fibrosis (secondary objectives). RESULTS: The incidence and quantity of intraocular fibrin were significantly lower in the patients treated with tPA than in the control group (p < 0.05). The frequencies of synechiae were reduced by tPA injection. The capsule fibrosis noted after 3 months was significantly lower in the tPA group (p = 0.027). No ocular side effects were noted after the tPA injections. CONCLUSIONS: Lysis of postcataract fibrin formation is accelerated and increased by a single intracameral injection of 10 micrograms tPA in addition to standard anti-inflammatory treatment. The findings suggest that the tPA injection reduces posterior capsule fibrosis, which still has to be addressed in larger study populations and with a long term follow up.  相似文献   

16.
Antibodies against Japanese encephalitis virus (JEV) were examined in 356 serum samples from individuals visiting Tribhuvan University Teaching Hospital using neutralization test. A total of 13.2% (47/356) seropositivity was observed. Antibody positivity against both Nakayama-NIH and Beijing-1 strains was seen in 7.9% subjects. Infection by Nakayama-NIH strain alone was seen to be 4.2% while 1.1% of study populations were found to be infected only by Beijing-1 strain. High antibody titer was observed in the 20-40 years age-group and did not increase with age. Seropositivity was more common in zone-A (Tarai) area compared to zone-B (Hills) and zone-C (Mountains). Spectrum of antigenicity of JEV in zone-A as shown by neutralization test was identical to Indian isolates (strains). Difference in seropositivity was observed against Nakayama-NIH and Beijing-1 strain in zone-B and C indicating recent spread of JEV in these areas.  相似文献   

17.
The purpose with this article is to describe the principles of change management in health services, as experienced in South Africa to date. The driving forces are highlighted, followed by a brief explanation of the three phases in change management. The principles and process of change management, as applied to the South African health system, are described as perceived by the author. The paper was read as an invited presentation at the Commonwealth Nurses Federation's General Meeting and workshop on 13 June 1997 in Vancouver, Canada.  相似文献   

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Spontaneous nasal tumors are rare in mice, and only one adenocarcinoma and two more primary neoplasms of the nose have been observed in our files of long-term feeding studies, which are composed of 3,419 male and 3,521 female CD-1 (Crl:CD-1 (ICR)BR) mice. This adenocarcinoma was a 1-cm-diameter mass observed grossly in the right nasal cavity of a 454-day-old, male CD-1 mouse from a treated group in a bioassay study conducted with 340 males and 340 females. The neoplastic epithelial cells affected the normal nasal architecture on the right side of the nose. Roughly, tumor neoplastic cells of the outer, lateral portion occurred as cuboidal to low columnar cells with basilarily located nuclei and eosinophilic cytoplasm. These cells were arranged in cylindrical profiles and frequently entrapped acini of the glands of the maxillary sinus. Neoplastic epithelial cells of the inner, medial portion appeared as serous acinar or ductular structures circumscribed by multiple lagers of myoepithelial-like cells. Staining failed to demonstrate mucous secretion. The site of origin of this neoplasm appeared to be the serous glands of the maxillary sinus. The adenocarcinoma was believed to be spontaneous.  相似文献   

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