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31.
Glutathione S-transferases are involved in the detoxification of carcinogens and xenobiotics and are potentially associated with the development of drug-resistance. Forty-six testicular germ cell tumors and 33 adjacent normal testicular tissue specimens were analyzed at the RNA level for the expression of glutathione S-transferase alpha and pi. Glutathione S-transferase alpha was expressed in 31 of the 33 normal testicular tissues (94%) but in only three of the 46 germ cell tumors (7%). Glutathione S-transferase pi mRNA was detected in all normal and malignant testicular tissue samples. Thirteen testicular germ cell tumors and eight normal testicular tissue samples were analyzed at the protein level. The mean specific activity of total cytosolic glutathione S-transferase in tumor tissue was decreased by about 80% as compared to normal testicular tissue. Protein analysis of the glutathione S-transferase subunits of normal testicular tissue demonstrated the presence of the glutathione S-transferase classes alpha, mu and pi, with a predominance of the mu class. In testicular germ cell tumors the glutathione S-transferase subunit pattern showed a predominance of glutathione S-transferase pi representing 88% +/- 3% of total glutathione S-transferase. Since all three glutathione S-transferase isoenzyme classes contribute to the resistance to antineoplastic drugs, the altered glutathione S-transferase isoenzyme pattern and the decrease of glutathione S-transferase activity may play a role in the high inherent drug sensitivity of human testicular germ cell tumors.  相似文献   
32.
The acuity card procedure has been shown to provide reliable grating acuity estimates in pediatric patients. The current study was conducted to determine the usefulness of this procedure in another group of persons in whom conventional acuity measurements are not possible, ie, nursing home residents who suffer from dementing disorders. Binocular visual acuity estimates were obtained in 13 cognitively impaired nursing home residents. Test sessions took 20-30 min each. Both test-retest agreement and inter-observer agreement of Teller Acuity Card (TAC) acuity estimates were good (within 0.5 octave for all residents), demonstrating that this procedure yields reasonable acuity estimates in noncommunicative nursing home residents. The authors stress the potential of this tool for nursing home administrators as well as for researchers.  相似文献   
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A 2?year-old boy had the onset of pain and swelling of his penis during the past 3 days. The swelling and pain increased significantly within the past 24 hours. The child's penis is shown in the Figure. DENOUEMENT AND DISCUSSION PARAPHIMOSIS Paraphimosis is an urologic emergency that results when the foreskin is retracted away from the glans penis and cannot be reduced to its former position. The opening in the prepuce, when forcibly retracted beyond the coronal sulcus, becomes a constricting ring that cannot be reduced. The constricting ring created causes a tension greater than the lymphatic pressure and results in edema of the prepuce, the penile shaft, and the glans penis distal to the incarcerated foreskin.1,2As lymphatic drainage is impaired and tissue swelling increases, reduction of the foreskin becomes more difficult. Pain occurs as a result of swelling, and, eventually, as a result of vascular compromise. If.  相似文献   
35.
Background. Hypoxia and warm ischemia produce severe injury to cardiac grafts harvested from non-heart-beating donors. To potentially improve recovery of such grafts, we studied the effects of intravenous phenylephrine preconditioning.

Methods. Thirty-seven blood-perfused rabbit hearts were studied. Three groups of non-heart-beating donors underwent intravenous treatment with phenylephrine at 12.5 (n = 8), 25 (n = 7), or 50 μg/kg (n = 7) before initiation of apnea. Non-heart-beating controls (n = 8) received saline vehicle. Hypoxic cardiac arrest occurred after 6 to 12 minutes of apnea, followed by 20 minutes of warm in vivo ischemia. A 45-minute period of ex vivo reperfusion ensued. Nonischemic controls (n = 7) were perfused without antecedent hypoxia or ischemia.

Results. Phenylephrine 25 μg/kg significantly delayed the onset of hypoxic cardiac arrest compared with saline controls (9.6 ± 0.5 versus 7.7 ± 0.4 minutes; p = 0.00001), yet improved recovery of left ventricular developed pressure compared with saline controls (57.1 ± 5.3 versus 41.0 ± 3.4 mm Hg; p = 0.04). Phenylephrine 25 μg/kg also yielded a trend toward less myocardial edema than saline vehicle (p = 0.09).

Conclusions. Functional recovery of nonbeating cardiac grafts is improved by preconditioning. We provide evidence that the myocardium can be preconditioned with phenylephrine against hypoxic cardiac arrest.  相似文献   

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37.
The mitochondrial genome of the selfed progeny of a plant regenerated from long-term somatic tissue culture displays specific structural rearrangements characterized by the appearance of novel restriction fragments. A mitochondrial DNA library was constructed from this selfed progeny in the SalI site of cosmid pHC79 and the novel fragments were subsequently studied. They were shown to arise from reciprocal recombination events involving DNA sequences present in the parental plant. The regions of recombination were sequenced and the nucleotide sequences were aligned with those of the presumptive parental fragments. We characterized an imperfect short repeated DNA sequence, 242 bp long, within which a 7-bb DNA repeat could act as a region of recombination. The use of PCR technology allowed us to show that these fragments were present in both parental plants and tissue cultures as low-abundance sequence arrangements.  相似文献   
38.
Lung cancer is the most prevalent malignancy in western countries and most of the patients present at advanced stages, but single splenic metastasis is exceptional instead. We report on a case of a seventy-three-year old male presenting with non-hemoptoic productive cough, constitutional syndrome and pain in the left lower quadrant. Physical examination and complementary radiological and hystologycal procedures revealed the presence of an adenocarcinoma of the left lung with probable splenic metastasis. The patient underwent splenectomy, which confirmed the diagnose of splenic metastasis of lung adenocarcinoma and, secondly, lung resection was performed. Topics about lung cancer metastasis are discussed.  相似文献   
39.
The dermatologist's procedure was introduced in 1972 by employers' liability insurance funds in the industrial, agricultural and public sectors of Germany's statutory occupational accident insurance as a "procedure for early detection of occupational skin diseases". So far, it is still the most relevant tool for secondary prevention in occupational dermatology in Germany. According to the intention of this procedure, insured persons with a skin disease in which an occupational aetiology is suspected must be offered preventive measures and, if necessary, given appropriate treatment to avoid their losing their jobs. On the initiative of the Central Federation of Industrial Professional Associations (HVBG), a study group was set up in 1999 from among its membership in cooperation with the Working Committee of Occupational and Environmental Dermatology (ABD) and the Professional Organisation of German Dermatologists (BVDD) to improve on the efficiency of the "classic" dermatologist's procedure. The proposed "optimised" dermatologist's procedure is based on the assumption that early detection followed by competent and intensified skin protection and skin care will be successful in retarding or stopping the progression of occupational dermatoses, while later treatment is likely to be less effective. In October 2002, a pilot study started in Northwest Germany to establish by scientific evaluation whether the implementation of secondary protective measures is definitively better when the provisional "optimised" dermatologist's procedure is followed. The study results should allow detailed suggestions for an improved dermatologist's procedure before it is introduced nationwide.  相似文献   
40.
Projection radiographic techniques have been used in a standardized manner for decades for the diagnosis of conditions of the foot and ankle; the indications for them and the pattern of findings useful in the initial diagnosis and monitoring of the course are generally known to clinical radiology staff. Computed tomography has been introduced as an extension of the basic procedures performed for diagnosis in the ankle and the hindfoot. In the case of complex fractures, however, specialist experience is essential. CT is an easily accessible investigative procedure and is meanwhile economical and very powerful. Magnetic resonance imaging supplements the range of investigations in special cases when there are particular problems. Microfractures, findings indicative of inflammation and/or dystrophy and, in particular questions concerning the musculoligamentous support system are the situations in which such investigations are needed. Ultrasound has an additive value vis-à-vis magnetic resonance imaging and is an easily accessible and highly effective examination procedure both for the primary diagnosis and for serial monitoring. Financial constraints in the healthcare sector are increasingly limiting purely medical indications. Regardless of this development, the retention of projection radiography, computer tomography, and magnetic resonance imaging must be demanded for the initial diagnosis in the care of foot and ankle injuries. The earliest possible implementation of all these techniques for the initial diagnosis is the first step towards effective treatment. Cafrefully chosen and, if appropriate, complementary strategies are needed for monitoring of the course and for assessment.  相似文献   
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