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71.
We observed a human immunodeficiency virus (HIV)-infected homosexual male with AIDS related complex (ARC) who had a serum globulin level of 80 g/L. Serum protein electrophoresis revealed a gamma globulin fraction of 40 g/L, of which 50% (20 g/L) was contained within a paraprotein spike, comprised predominantly of IgG kappa. This patient also had high titer anti-HIV antibodies in his serum, which were Western blot reactive at a final dilution of 1:500,000, and recognized gp120env, p66pol, p55gag, p53pol, p41gag, and p24gag. Because paraproteins in the past have been shown to be directed against specific antigens, we purified this patient's paraprotein using a modified high performance liquid chromatography (HPLC)-hydroxylapatite procedure and tested the purified paraprotein for anti-HIV antibody activity. The purified paraprotein retained anti-HIV antibody activity to a final dilution of 1:100,000, and recognized p66pol, p55gag, p53pol, p41gag, and p24gag. The recognition of both "gag" and "pol" gene products suggested that the purified paraprotein might not be monoclonal in origin. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) demonstrated that the purified paraprotein contained at least two immunoglobulin light chain species (Mol wt 30 to 33 Kd). Affinity chromatography of the purified paraprotein using a p24- Sepharose 4B matrix separated the "gag" and "pol" antibody activities. Immunoglobulin gene rearrangement analysis of a bone marrow aspirate (which contained 15% plasma cells) failed to reveal a clonal population of immunoglobulin producing cells. We conclude that this patient's paraprotein accounted for most of the anti-HIV activity present in whole serum, and that this paraprotein was not monoclonal in origin.  相似文献   
72.
培养心肌细胞牵张刺激装置的建立及应用   总被引:2,自引:2,他引:2  
1 方法 牵张刺激装置的制作如模式图 1.制作实验模型采用材料为有机玻璃板、2 4孔培养板、硅胶膜 (厚度 0 .2 2 μm) .硅胶膜从平面圆形变为球形时 ,面积扩大的百分比 =(S球 -S园 ) /S园 ,其中S球 =AD2 ,S园 =r2 ,而AD2 =h2 +r2 ,其中r为孔的半径 ,h为膜升高的高度图 2 .通过控制h的大小 ,可控制膜被牵拉的强度 .本实验采用使膜面积扩大 2 0 %的强度 ,故h =4mm[1] .参照Kassiri等[2 ,3 ] 方法进行心肌细胞的分离培养 .生长有贴壁心肌细胞的 2 4孔板被固定于牵张装置 ,缓慢充气使硅胶膜向上凸起 4mm ,分别维持…  相似文献   
73.
Meniscal injuries: detection using MR imaging   总被引:15,自引:0,他引:15  
Both retrospective and blinded analyses of thin-section, high-resolution magnetic resonance (MR) images of the knee joint, produced using a solenoid surface coil, indicate that MR imaging is an effective technique for evaluating meniscal injuries. Images of 49 patients were evaluated, and the results were correlated with those of subsequent arthroscopy. A grading scale was developed to rate the index of suspicion of a meniscal tear based on the MR images. Overall, approximately 80% of menisci rated grade 4 (definite tear) or 3 (probable tear) were found to have corresponding tears at arthroscopy. In many other patients with a grade 4 or 3 meniscus in whom a corresponding tear was not found arthroscopically, meniscal tears at other sites or other abnormalities were correctly diagnosed using MR. A majority of the false-positive MR images involved the posterior horns of the menisci, the sites of most false-negative arthroscopic diagnoses. The predictive value of a negative MR image was almost 100%. Even in patients with moderate-to-large effusions, the menisci were accurately evaluated. The results imply that MR imaging is useful in the preoperative evaluation of suspected meniscal tears.  相似文献   
74.
75.
Aim  Worster-Drought syndrome (WDS), or congenital suprabulbar paresis, is a permanent movement disorder of the bulbar muscles causing persistent difficulties with swallowing, feeding, speech, and saliva control owing to a non-progressive disturbance in early brain development. As such, it falls within the cerebral palsies. The aim of this study was to describe the physical and neuropsychological profiles of children with WDS.
Method  Forty-two children with WDS (26 males, 16 females; mean age 7y 10mo, SD 3y 1mo; range 2y 6mo to 16y 5mo) were studied prospectively using a standard protocol.
Results  All of the children had severe bulbar dysfunction; 36 out of 42 had feeding difficulties and 23 of 38 had unintelligible speech, which was poorly compensated for by augmentative communication. There were accompanying disturbances in cognition (mean non-verbal IQ 59), behaviour (12/40 attention-deficit–hyperactivity disorder [ADHD]), social communication (8/42 autism), and epilepsy (12/39). The severity of bulbar dysfunction and impact of additional impairments made it difficult to use formal assessments.
Interpretation  WDS causes severe and persistent bulbar dysfunction that is often accompanied by additional impairments, as in other cerebral palsies. Speech prognosis is particularly poor. Early diagnosis with appreciation of the underlying neurology would encourage critical evaluation of interventions and long-term planning to improve outcome.  相似文献   
76.

Background

Leishmaniasis is one of the infectious parasitic diseases of highest incidence in the world. Cutaneous Leishmaniasis (CL) has long been reported in Shiraz, Southern Iran. There is a need to find a sensitive and specific method for treatment and control of the disease.

Methods

We have compared the sensitivity of the conventional methods microscopy and cultivation of lesion scrapes against PCR amplification of parasite kinetoplast DNA from these samples. The samples (n=219) were obtained from the patients clinically suspected of CL. The smears were stained with Giemsa for microscopy and cultured in Novy-Nicolle-McNeal (NNN) blood agar for promastigote growth. For PCR, the dry smears were scraped off the slides and DNA was extracted.

Results

The positive rates from 219 specimens were 76.71%, 50.68%, and 93.61% for microscopy, cultivation, and PCR, respectively. The highest correlation was found between PCR and microscopy method (P=0.014). In PCR assay, 95.61%, 3.9%, and 0.49% of the samples were identified as Leishmania major, L. tropica, and dermatropic L. infantum, respectively.

Conclusion

The PCR method appears to be the most sensitive for the diagnosis of CL and is valuable for identifying the other species of Leishmania with confusing dermatropic signs.  相似文献   
77.
OBJECTIVES: To assess the knowledge and clinical practice of dental students in infection control procedures at a UK dental hospital.
DESIGN: A questionnaire concerning various aspects of infection control was completed by all clinical dental students under examination conditions. Their actual clinical practice was later observed and certain aspects recorded.
SETTING: A UK dental hospital.
SUBJECTS: One hundred and eleven dental students from three clinical years completed the questionnaire. Clinical practice for all 3 years was observed in a total of 280 treatment events.
METHODS: The questionnaire was marked by two of the authors and observations recorded by another author. MAIN OUTCOME MEASURES: Degree of compliance with recognised policy for infection control.
RESULTS: Knowledge of infection control procedures was variable particularly concerning duties usually undertaken by the dental nurse. The suggested high compliance with masks and eye protection was not always apparent in clinical practice, although virtually all students washed their hands prior to donning gloves, which were worn by all students.
CONCLUSION: There can be marked differences between what students say they would do and what they actually do in clinical practice. The topic of infection control requires a pro-active approach throughout the course, since results for the final year were not significantly different from the other clinical yearS. Ways of improving compliance are discussed.  相似文献   
78.
79.
Instability after rupture of anterior cruciate ligament (ACL) may lead to recurrent episodes of giving way, an increased risk of meniscal injury and premature degenerative changes. A total of 25 cases with ACL injuries were evaluated after reconstruction with bone patellar tendon bone graft through a mini-arthrotomy. All patients were male. Maximum number of patients were between 25-30 years of age (40%). The most common modality of injury was contact sports (44%). Most common complaint was instability of knee (100%). Average Lysholm score increased from pre-operative of 47 (27-75) to post-operative of 87 (68-95). Two patients (8%) had retropatellar pain. Moderate to severe graft site tenderness was present in 4 (21%). After an average follow up of one year three months, the results were comparable with the results of arthroscopic reconstruction.Key Words: Anterior cruciate ligament reconstruction, Mini arthrotomy  相似文献   
80.
祛白酊质量标准的实验研究   总被引:1,自引:0,他引:1  
目的:建立祛白酊的质量标准。方法:采用薄层色谱法鉴别其中的补骨脂素,异补骨脂素,栀子苷;导数分光光度法测定其中醋酸氢化可的松的含量。结果;薄层色谱鉴别方法有良好的重现性,专属性;醋酸氢化可的松在11-19ug.ml^-1呈良好的线性关系(r=0.9996)其含量测定平均回收率100.9%,RSD=0.9%(n=5)。结论:制定的质量标准可以保证祛白酊的质量。  相似文献   
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