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101.
Schmied BM Ulrich AB Matsuzaki H El-Metwally TH Ding X Fernandes ME Adrian TE Chaney WG Batra SK Pour PM 《Carcinogenesis》2000,21(6):1121-1127
Tumor transplants into nude mice (NM) may reveal abnormal biological behavior compared with the original tumor. Despite this, human tumor xenografts in NM have been widely used to study the biology of tumors and to establish diagnostic and therapeutic modalities. Clearly, precise differences in the biology of a given tumor in human and in NM cannot be assessed. We compared the growth kinetics, differentiation pattern and karyotype of an anaplastic Syrian hamster pancreatic cancer cell line in NM and in allogenic hamsters. As with the original tumor, transplants in hamsters grew fast, were anaplastic and expressed markers related to tumor malignancy like galectin 3, TGF-alpha and its receptor EGFR at high levels. However, tumors in the NM were well-differentiated adenocarcinomas, grew slower, had increased apoptotic rate and had a high expression of differentiation markers such as blood group A antigen, DU-PAN-2, carbonic anhydrase II, TGF-beta(2) and mucin. Karyotypically, the tumors in the NM acquired additional chromosomal damage. Our results demonstrate significant differences in the morphology and biology of tumors grown in NM and the allogenic host, and call for caution in extrapolating data obtained from xenografts to primary cancer. 相似文献
102.
The mechanical response of the vas induced by field stimulation is described in this paper. The experiments were performed, in vitro, on vasa from Sprague-Dawley albino rats. In the maintained ac tetanic stimulation, the active force achieves the peak magnitude in about 1 to 1.2 sec; thereafter, it relaxes gradually. For a given stimulus voltage (amplitude), a maximal response is elicited at 60 Hz. At 6000 Hz, and greater, no response is elicited. The ability to respond to stimulus dies out in 2 hr at 5 degrees C above the normal temperature of 37 degrees C; the ability to respond to stimulus remains unaffected at 5 degrees C below the normal temperature. The active force is always larger than the passive force when the vas is subjected to titanic stimulation near its in situ length. 相似文献
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106.
Kielmann K Deshmukh D Deshpande S Datye V Porter J Rangan S 《Social science & medicine (1982)》2005,61(7):1540-1550
Changing epidemiological patterns and the advent of new rapid diagnostic technologies and therapies have created considerable uncertainty for providers working in HIV. In India, the demand for HIV care is increasingly being met by private practitioners (PPs), yet little is known about how they deal with the challenges of managing HIV patients. To explore HIV management practices in the private medical sector, a survey was conducted with 215PPs in Pune, India, followed by in-depth interviews focusing on the social context of practice among a sub-set of 27PPs. Drawing primarily on interview data, this paper illustrates a number of uncertainties that underlie the reported actions of providers in a competitive medical market. PPs perceive HIV as a 'new' and challenging disease for which they lack adequate knowledge and skills. Combined with the perceived high cost and complexity of antiretroviral treatment, preconceptions about HIV patients' social, financial and mental capacity lead to highly individualistic management practices. While these fall short of clinical 'best practice' guidelines, they reflect adaptive responses to the wider uncertainties surrounding HIV care in urban India. By highlighting contextual issues in PPs' management of HIV patients, the paper suggests the need to explicitly acknowledge the social, moral and economic bases of uncertainty beyond the clinical setting. 相似文献
107.
Background/Purpose
There is currently no evidence-based screening instrument to assist in the detection of physical child abuse patients. The screening index for physical child abuse (SIPCA) was previously developed as a potentially new tool for this need. It is a scale that assigns point values, on the basis of variable weights from logistic regression models, to age and patterns of injuries (including fracture of base or vault of skull, contusion of eye, rib fracture, intracranial bleeding, multiple burns), with higher scores indicating greater suspicion for abuse. The purpose of this study is to validate this new tool in another independent data set.Methods
A cross-sectional hospital discharge database from 1961 hospitals in 17 states is used (n = 58558). Children aged 14 years or younger with International Classification of Diseases, Ninth Revision, Clinical Modification codes 800 to 959 are included for analysis. Child abuse cases are identified by E codes and certain International Classification of Diseases, Ninth Revision, Clinical Modification codes in the 995.5x range. Screening index for physical child abuse performance is evaluated by discrimination (receiver operating characteristic) and goodness of fit (pseudo r2).Results
A total of 447 abused patients (0.76%) was identified. The receiver operating characteristic of SIPCA in this data set is 0.89 as compared with 0.86 in the development data set. The pseudo r2 of SIPCA in this data set is 0.26 as compared with 0.28 in the development data set. A SIPCA score of 3 has a sensitivity of 86.6% and a specificity of 80.5% for detecting physical abuse; raising the threshold to a score of 4 improves the specificity to 93.1% but at a loss of sensitivity to 71.8%.Conclusions
The validity of the new SIPCA instrument is supported by its performance in an independently derived data set. A score of 3 on SIPCA represents a balanced trade off in the sensitivity and specificity of the instrument in detecting physical abuse and is an optimal threshold above which to begin considering abuse in differential diagnosis. Application of the instrument could assist clinicians in detecting physical child abuse cases among pediatric trauma patients. 相似文献108.
109.
Facial asymmetry after unilateral ankylosis results due to the loss of the condylar growth center on the ankylosed side. This results in the skeletal midline deviating to the affected side, a lack of vertical growth on the same side produces a cant of the occlusal plane and mandibular retrognathism is seen as a result of the hypoplasia. The lower border of the mandibular corpus and angle on the contra lateral side is usually flattened. We report a case of facial asymmetry following unilateral ankylosis, which was treated by a combined approach with distraction osteogenesis and orthodontics. Inexpensive orthopedic finger distractors were used. The facial changes were analyzed using the Grummons facial asymmetry analysis. 相似文献
110.
Meningococcal disease occurs both endemically and epidemically across the world. In India also meningococcal disease occurs sporadically with epidemics occurring at regular intervals. Epidemics of meningococcal disease have occurred in Delhi in the year 1935, then in the year 1966 which lasted for a year and again in 1985-86. The last epidemic took a great toll with case fatality rate nearly 13%. This year also there has been an outbreak of meningococcal disease with nearly 400 cases and case fatality rates of about 10% majority are males between the age group of 21-30 years and from the inner crowded areas of the city. 相似文献