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Because of their high degree of polymorphisms, the variable number of tandem repeat (VNTR) loci have become extremely useful in studies involving gene mapping, determination of identity and relatedness of individuals, and evolutionary relationships among populations. However, there are some concerns regarding whether or not the patterns of such genetic variation can be studied by the classical population models that are developed for studying genetic variation at blood groups and protein loci, since VNTR alleles detected by molecular size may not always be identical by descent. Although theoretical and empirical studies demonstrate that this concern is overstated, this study provides further support of the application of the traditional mutation-drift models to predict the pattern of intra- and inter-populational variation at VNTR loci. By comparing genetic variation at six VNTR loci with that at 16 blood groups and protein loci in three ethnically defined populations, we show that the patterns of variability at these two sets of loci are in general parallel to each other. Shared VNTR alleles among populations are generally more frequent than the ones which are not present in every population; the proportion of shared alleles among populations increases with increasing genetic similarity of populations; and the number of VNTR alleles is positively correlated with gene diversity at these loci. All of these observations are in agreement with the prediction of the mutation-drift models, particularly when the possibility of forward-backward mutations are taken into account. This parallelism of genetic variation at VNTR loci and blood groups/protein loci further asserts the potential of using such hypervariable loci for microevoltionary studies, where closely related populations may exhibit considerably less allele frequency differences at the classical blood group and protein loci. © 1992 Wiley-Liss, Inc.  相似文献   
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Summary RSV infection continues to be a major cause of morbidity and mortality throughout the world. Despite advances in the understanding of its pathogenesis, limited progress has been made in prevention and treatment of RSV infection. Based on the experiences thus far it seems that control of RSV infection will be a difficult and complex task.  相似文献   
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Progression or reactivation of Otosclerotic disease as shown by tomography, despitemoderate dosage Sodium Fluoride therapy, is due to poor intestinal absorption of the drug in its enteric coated form. It is also seen when the drug is often temporarily withdrawn. During Sodium Fluoride therapy for Otosclerosis an intestinal absorption test of the preparation is necessary.  相似文献   
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OBJECTIVE: To compare the acceptability, efficacy, adverse effects, and user satisfaction of a levonorgestrel intrauterine system (LNG-IUS) and transcervical resection of the endometrium (TCRE) for the treatment of dysfunctional uterine bleeding. METHOD: Of 50 women with a pictoral blood loss assessment chart (PBAC) score of 100 or greater, 25 had a LNG-IUS inserted (Mirena; Schering, Berlin, Germany) and 25 underwent TCRE. Procedure-related complications, PBAC score, hemoglobin levels, adverse effects, and rates of acceptability and satisfaction were recorded at 3-month intervals for a period of 12 months. RESULTS: At the end of 1 year there were a 97% and a 94% reduction in menstrual blood loss in the LNG-IUS and TCRE groups, respectively, and hemoglobin concentration had increased by 5.5% in the LNG-IUS group and 5.2% in the TCRE group. Adverse effects were similar in both groups except for systemic effects, which were seen only in the LNG-IUS group. Satisfaction rates were about 80% in the 2 groups. CONCLUSION: Both treatments were found to be equally effective but LNG-IUS placement requires less operator skill and entails no operative hazards, and the device provides effective contraception.  相似文献   
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Lateral Ankle sprain is a common sports-related trauma with the mechanism of injury ranging from inversion to plantar flexion. These injuries commonly affect the ligaments but can also affect the associated soft tissue structures like the eversion muscles and tendons. Prompt and accurate diagnosis of such injuries is warranted so as to ensure early return to play and prevent long-term complications. Lateral ankle sprain injuries in sports may not always be associated with ligament injuries. We report a never before reported case of lateral ankle sprain injury in a soccer player with the unusual finding of isolated partial tear of Extensor digitorum longus muscle and its fascia leading to myo-fascial herniation. The lateral ankle ligaments were intact. The diagnosis was clinched on a high-frequency ultrasound scan supported by dynamic maneuvers which in fact proved to be superior to MRI as the latter failed to demonstrate the myo-fascial herniation in our case. We therefore propose that real-time ultrasound scanning with dynamic maneuvers should be the first line of investigation to assess sports injuries in anatomically complex joints like the ankle.  相似文献   
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OBJECTIVE: Non-cirrhotic portal hypertension (NCPH) is a common cause of portal hypertension in developing countries, especially Asia. Recent data have shown near-normal reproductive function and good pregnancy outcome for NCPH compared with cirrhosis. The aim of the present study was to evaluate complications during pregnancy and pregnancy outcome in women with NCPH. METHODS: Twelve pregnancies in five patients with NCPH were evaluated. RESULTS: In the present study, 20% of patients had hematemesis during pregnancy that was managed successfully. Four patients (80%) had severe anemia (hemoglobin 6-7 g%) and three (60%) had thrombocytopenia. There were no preterm births. Of a total of nine live births, six were vaginal deliveries and three were delivered by Cesarean section (performed for obstetric indications). Four babies (44%) were small for gestational age (SGA). CONCLUSIONS: The results show that patients with NCPH have normal fertility, no apparent increase in the incidence of hematemesis during pregnancy, an increased incidence of SGA babies and no indication for elective Cesarean delivery.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Tamilnadia uliginosa (Retz) Tirveng and Sastre (Rubiaceae) is a small edible medicinal plant utilized in...  相似文献   
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Purpose:The aim of this study was to examine the pathology of retinoblastoma (RB) seeds with supportive evidence by field emission scanning electron microscopy and Raman spectroscopy.Methods:This study was a laboratory-based observational study. Enucleated eyeballs received in the ocular pathology department of a tertiary eye care center in northeast India were included in the cohort after obtaining written informed consent during the surgery. The study was carried out for 6 years (2015–2020). Most of the eyeballs were Group-E RBs. Standard eyeballs sectioning were done by bread loaf techniques. Gross documentations included RB seeds seen in the smallest calotte done with utmost care. Seeds were documented also in permanent sections. Scanning electron microscopy and Raman spectroscopy were carried out in an index case.Results:Out of the total 59 cases, 35 RB cases had different seedings. The mean age at enucleation was 2.9 years. RB seeds were seen in vitreous (n = 19), subretinal plus vitreous (n = 7), anterior chamber (n = 1), over crystalline lens (n = 3), retinal surface (n = 1), retinal pigment epithelium (RPE; n = 2), subretinal (n = 1), calcified seeds (n = 2). Other characteristics were dusts (n = 7), clouds (n = 11), spheres (n = 4), and unspecified type (n = 13). Histopathological high-risk factors showed significant choroidal (n = 22) and optic nerve (n = 15) involvement. Few cases had extraocular spread. Undifferentiated tumor (n = 24) was seen with higher evidence of necrosis (n = 23). Raman spectra differentiated the seeds from the normal tissue on the basis of lipid and protein content.Conclusion:This study highlights the different types of RB seeds with high-risk factors. The morphology of those seeds showed the difference between vitreous and subretinal seeds under advanced microscopic observations.  相似文献   
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