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81.

Purpose

We determined if the behavior of germ cell tumors metastatic to the mediastinum is different from that of primary mediastinal germ cell tumors, a group known to have distinct clinical features.

Materials and Methods

A search of the computerized data base for germ cell tumors metastatic to the mediastinum at our university revealed 80 patients, 65 of whom underwent concomitant retroperitoneal lymph node dissection at mediastinal surgery.

Results

Of the patients 60 (75 percent) are free of disease, 14 (18 percent) died of cancer and 6 (8 percent) are living with disease. Mediastinal pathology included teratoma in 65 percent of the patients, cancer in 26 percent and fibrosis in 9 percent. Of the 65 patients who underwent retroperitoneal lymph node dissection 75 percent had teratoma, 15 percent had fibrosis and 10 percent had cancer. Mediastinal relapses after dissection were rare (4 of 80 patients).

Conclusions

Germ cell tumors metastatic to the mediastinum appear to behave similarly to those metastatic to the retroperitoneum. Primary mediastinal germ cell tumors have an entirely different clinical course. Teratoma is the predominant pathological type of post-chemotherapy germ cell cancer metastatic to the mediastinum.  相似文献   
82.
In 43 young rabbits, the tendo Achilles and flexor digitorum longus tendon were excised and replaced by filamentous carbon fiber. Tendo-Achilles in controls was repaired by silk or nylon sutures or left without replacement. Concurrent excision of the posterior tibial nerve was performed in one group of the carbon-replacing tendo-Achilles operations. When fully functioning, carbon-induced "neotendon" rapidly developed from young fibroblastic tissue outgrowths of the loose mesenchymal tissue of the perineurium and adventitia of the blood vessels in the adjacent neurovascular bundle. Silk or nylon replacement of the excised Achilles tendon did not lead to successful production of a new substitute. Carbon fibers were unsatisfactory for replacement implants for the flexor digitorum longus tendons.  相似文献   
83.
The continued growth of hospital and clinical pharmacy should be paralleled by the development of sound research methods justifying innovative practices. Such research will, on occasion, require experimentation involving human subjects. The principal means of assuring that the welfare of research participants is not compromised is through the procurement of effective informed consent. Pharmacists, like many other health professionals, have had relatively little exposure to methodology involved in the writing of an informed consent instrument. A comprehensive document must not only conform to the requirements of federal regulatory agencies, but must also satisfy various institutional guidelines. Past instances of unethical human experimentation are discussed, and a format for preparation of an informed consent instrument is examined. Circumstances requiring informed consent and identification of the basic elements of consent are also explained.  相似文献   
84.
85.
We report the unusual case of a 43-year-old woman who presented with Romberg's progressive facial hemiatrophy and spontaneous scleral perforation in the ipsilateral eye, for which scleral grafting was performed. Histologic and ultrastructural examination of the scleral specimen revealed a noninflammatory lytic process. The location of the scleral loss, exactly on the line of the "en coup de sabre" atrophy, as well as the light microscopy and ultrastructural histopathologic findings suggest that the scleral destruction was a late manifestation of Romberg's disease.  相似文献   
86.
87.
A new method is described for recording the emotion-induced decrease in skin resistance area, which is known as the skin-resistance response (SRR). The method employs a simple current source and a new type of tetrapolar electrode in which the SRR is measured with the non-current-carrying electrodes. The signal produced can be recorded with a standard electrocardiograph. Typical SRRs from two subjects are presented.  相似文献   
88.
The effects of aging on the responsiveness of hippocampal neurons to iontophoretic application of L-glutamate and AMPA were studied in vitro. There were no effects of age on neuronal responses to L-glutamate; however, CA1 pyramidal cells of old rats, but not granule cells in the fascia dentata, showed both a smaller reduction in extracellularly-recorded synaptic responses following application of AMPA (presumably mediated by depolarization), and smaller extracellular "DC" fields (measured by subtracting the DC potentials at the dendrite and soma following AMPA application in the dendrites). To examine the cellular bases of this age-related alteration in AMPA sensitivity, two additional electrophysiological approaches were used: (1) measurement of the amplitude ratios of extracellular EPSP and fiber potential components of the Schaffer collateral-CA1 response; (2) measurement of intracellularly recorded unitary EPSPs and quantal analysis of their fluctuations. The interpretations that would be placed on four hypothetical possible outcomes of such experiments are outlined and assessed in relation to the experimental data. The pattern of results obtained in the present experiments supports the following conclusions: In old rats, individual Schaffer collateral synapses do not appear to have altered AMPA receptor properties, as neither the mean size of the unitary synaptic response nor the apparent quantal size differs between age groups; however, the data do support the conclusion that there are fewer synapses per Schaffer collateral branch in old versus young CA1 pyramidal cells.  相似文献   
89.
The Colorado Client Assessment Record (CCAR) is a problem checklist and level of functioning rating instrument used to describe admission to a public mental health system. A brief, non-technical summary of recent research and administrative applications involving this instrument is presented. A stable factor structure, generalizable to several diverse client populations, is reported. Scaling procedures for measuring these procedures and a client typology based on this scaling are described. The client typology is differentially related to the types of services received and the costs of treatment episodes. The typology is also used to understand differences in case mixes and lengths of stay at two state hospitals.  相似文献   
90.
The addition of supplementary cytosolic fraction greatly enhancesthe activation of 2-acetylamlnofluorene (AAF) by uninduced 9,000x g supernatant fraction (S9) in the Ames test. Uninduced S9is poor at activating AAF in the Ames test (although it is effectivein the liquid based fluctuation test) probably because cytosolizmaterial diffuses into the bottom agar. An enhancing effectof cytosol supplementation was also observed with 2-aminoanthracene(AA) and 2-aminofluorene (AF) with uninduced S9. Using Aroclor-inducedpreparations, supplementation with cytosol enhanced the activationof benzo[a]pyrene and ethidium bromide. With AAF and Aroclor-inducedpreparations, supplementation with cytosol produces a slightbut significant increase in activation, but interpretation iscomplicated by the fact that Aroclor 105,000 x g supernatantfraction (S105) alone efficiently activates AAF, AF and AA.Norharman potentiated the enhancing effect of Arodor S105 onArodor-S9 activation of AAF but inhibited the activation ofAAF by S105 fraction alone. The enhancing effect of S105 fractionmay explain some, but not all, of the differences between liquidbased and agar overlay based activation.  相似文献   
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