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1.
Schlu?folgerungen Für die Peritonealkarzinose bei rezidivierendem Ovarialkarzinom sollte die IHCP als Konsolidierungstherapie nach neuerlicher zytoreduktiver Chirurgie in Erw?gung gezogen werden. Bei grobknotiger diffuser Carcinosis peritonei und massivem Aszites kann die IHCP über l?ngerer Zeit dessen Neubildung verhindern und damit zu einer Verbesserung der Lebensqualit?t und Verl?ngerung der überlebenszeit beitragen.  相似文献   
2.
Three patients presented with giant aneurysms of the intracranial internal carotid artery that became symptomatic with expanding mass effects 4-10 years after severe head trauma accompanied by skull base injuries at the site of aneurysm formation. These aneurysms are therefore considered to be late manifestations of traumatic vessel disruption. Posttraumatic aneurysm growth was documented in one case of a supraclinoidal aneurysm. One intracavernous aneurysm was combined with a traumatic carotid-cavernous sinus fistula. Although the origin of intracranial aneurysms is usually considered to be traumatic only within a period of weeks or months after head injuries, giant aneurysms of the intracranial internal carotid may represent late complications of trauma in a number of cases.  相似文献   
3.
Extracorporeal membrane oxygenation (ECMO) has been successful (greater than 80% survival) in 35 centers in greater than 900 newborns with severe respiratory failure having an estimated mortality of greater than 80% on conventional management. During the last 3 years we have treated 79 newborns with 74 survivors (94%). Their diagnoses included meconium aspiration, persistent fetal circulation, respiratory distress syndrome, congenital diaphragmatic hernia, and sepsis. Seven patients (9%) had life-threatening intrathoracic complications requiring emergent intervention while on ECMO: tension hemothorax (3), tension pneumothorax (2), and pericardial tamponade (2). Pericardial tamponade and tension hemothorax and pneumothorax show a similar pathophysiology of increasing intrapericardial pressure and decreasing venous return. Perfusion is initially maintained by the nonpulsatile flow of the ECMO circuit before further decrease in venous return results in decreasing ECMO flow and progressive hemodynamic deterioration. Each of the seven patients demonstrated a clinical triad that includes increasing PaO2 and decreasing peripheral perfusion (as evidenced by decreasing pulse pressure and decreasing SvO2) followed by decreasing ECMO flow with progressive deterioration. The diagnoses were confirmed by transillumination, chest x-ray, or cardiac echocardiogram. Initial emergent placement of a percutaneous drainage catheter was temporizing in all seven cases. However, four patients required emergent thoracotomy for definitive treatment while still on ECMO. All seven patients were weaned from ECMO and are short-term survivors (6 months to 3.5 years). As use of ECMO for newborn severe respiratory failure increases, responsible physicians must be familiar with life-threatening intrathoracic complications and appropriate treatment strategies.  相似文献   
4.
Equating the condition after cardiac arrest with that of medial temporal damage, and consequently medial temporal lobe amnesia, is questioned on the basis of results from a patient who was studied neuropsychologically as well as with static and dynamic imaging methods (MRI, PET) 6–9 months after a heart attack. The patient manifested severe and persistent anterograde and retrograde amnesia, as well as further cognitive deteriorations. While MRI only indicated non-specific cortical atrophy, PET revealed a severe bilateral affection of the thalamus and of both medial and lateral temporal cortices as well as occipito-parietal hypometabolism. The neuropsychological status indicates that patients with a diagnosis of cardiac arrest may suffer very severe and persistent cognitive deficits; the imaging analyses show that cardiac arrests may lead to quite severe and widespread brain damage which, however, may not be visible with current magnetic resonance imaging technology, but which is clearly apparent from positron emission tomography. These data suggest that patients with a condition after a heart attack may not be valid models for pure hippocampal—or even medial temporal lobe—pathology, as they may suffer much more widespread brain damage.  相似文献   
5.
6.
Mutations in the connexin 26 (Cx26) gene (GJB2) are associated with autosomal nonsyndromic sensorineural hearing loss. This study describes mutations in the Cx26 gene in cases of familial and sporadic hearing loss (HL) by gene sequencing and identifies the allelic frequency of the most common mutation leading to HL (35delG) in the population of eastern Austria. For this purpose we have developed and applied a molecular beacon based real-time mutation detection assay. Mutation frequencies in the Cx26 gene of individuals from affected families (14 out of 46) and sporadic cases (11 out of 40) were 30.4% and 27.5%, respectively. In addition to known disease related alterations, a novel mutation 262 G-->T (A88S) was also identified. 35delG accounted for almost 77% of all Cx26 mutations detected and displayed an allelic frequency in the normal hearing population of 1.7% (2 out of 120). The high prevalence of the 35delG mutation in eastern Austria would therefore allow screening of individuals and family members with Cx26 dependent deafness by a highly specific and semi-automated method.  相似文献   
7.
The glucose metabolic rate of the human brain can be measured with labeled deoxyglucose, using positron emission tomography, provided certain conditions are fulfilled. The original method assumed irreversible trapping of deoxyglucose metabolites in brain during the experimental period, and it further requires that a conversion factor between deoxyglucose and glucose, the "lumped constant," be known for the brain regions of interest. We examined the assumption of irreversible trapping of fluorodeoxyglucose metabolites in brain of four patients in 365 normal and 4 recently infarcted regions. The average net, steady-state rate of fluorodeoxyglucose (KD) accumulation in normal regions of the four patients was 0.025 ml g-1 min-1. We also examined the variability of the lumped constant. We first confirmed that methylglucose is not phosphorylated in the human brain. We then estimated the lumped constant from the regional distribution of labeled methylglucose in brain. The average (virtual) volume of distribution of labeled methylglucose in the normal regions was 0.46 ml g-1 and was the same in both gray and white matter structures. The average brain glucose content corresponding to this value was 1.3 mumol g-1, assuming a Michaelis constant (Kt) of 3.7 mM for glucose transport across the blood-brain barrier. The lumped constant varied insignificantly between 0.4 and 0.5 in most regions, with an overall average of 0.44. It did not vary significantly between the patients and was the same in gray and white matter structures, but was inversely related to the calculated metabolic rate. This observation indicates that metabolic rates calculated with a fixed lumped constant (e.g., 0.40) would be slightly underestimated at high metabolic rates and slightly overestimated at low metabolic rates. The average glucose metabolic rates of the 365 normal regions, in which gray matter regions prevailed by 20:1, was 32 mumol 100 g-1 min-1. The average glucose phosphorylation rate in white matter was 20 mumol 100 g-1 min-1 with a lumped constant of 0.45. In the recently infarcted areas, the lumped constants varied from 0.37 to 2.83, corresponding to glucose metabolic rates varying from 2 to 18 mumol 100 g-1 min-1. Two infarct types were identified. In one type, the phosphorylation-limited type, glucose content and the lumped constant were close to normal (1 mumol g-1 and 0.40, respectively). In the other, the transport/flow-limited type, the glucose content was low (0.2 mumol g-1), and the lumped constant in excess of unity. The evidence from the present study upholds the model of Sokoloff et al. in every detail.  相似文献   
8.
Progression rates of Alzheimer's disease (AD) vary considerably, and they are particularly difficult to predict in patients with mild cognitive impairment. We performed a prospective multicenter cohort study in 186 patients with possible or probable AD, mostly with presenile onset. In a cross-sectional analysis at entry, impairment of glucose metabolism in temporoparietal or frontal association areas measured with positron emission tomography was significantly associated with dementia severity, clinical classification as possible versus probable AD, presence of multiple cognitive deficits and history of progression. A prospective longitudinal analysis showed a significant association between initial metabolic impairment and subsequent clinical deterioration. In patients with mild cognitive deficits at entry, the risk of deterioration was up to 4.7 times higher if the metabolism was severely impaired than with mild or absent metabolic impairment. Copyrightz1999S.KargerAG, Basel  相似文献   
9.
Summary The effects of antineoplastic treatment on gliomas are related to tumour cell cycle and proliferation kinetics, glioma tissue architecture, and the surrounding environment. Morphological changes induced by radiation and chemotherapy are characterized by cell necrosis and severe alterations in cell and nuclear morphology caused by changes in the cell kinetic parameters which, however, may also occur spontaneously in untreated anaplastic gliomas.Comparative studies of cytological imprints and routine histological preparations of biopsy and autopsy specimens were performed in four groups of anaplastic astrocytomas and glioblastomas (78 cases) with postsurgical irradiation, combination chemotherapy, and CCNU treatment, and without specific postsurgical treatment (control group). Following radiation and chemotherapy, in addition to increased necrosis and vascular response, a variety of characteristic but nonspecific changes were observed in cell and nuclear morphology with prominent formation of multinucleated giant and monstrous cells, irregular and hyperchromatic nuclei, and severe cytoplasmic degeneration indicating both inhibition of cell division and cell damage. Statistically significant findings were a posttreatment increase in the number of multinucleated giant and monstrous cells and a decrease in the number of mitoses. These changes were more pronounced after chemotherapy than after radiation, while no significant dissimilarities were found between combination chemotherapy and CCNU. The implications of these changes on the mechanisms of antitumour treatment in anaplastic gliomas are discussed.
Morphologische Veränderungen in anaplastischen Gliomen nach Strahlen- und Chemotherapie
Zusammenfassung Die Wirkung anuneoplastisdier Behandlung auf Gliome ist abhängig von der Tumorzeil- und Proliferationskinetik, der Gliomarchitektur und dem umgebenden Hirngewebe. Durch Strahlen- und Chemotherapie induzierte morphologische Veränderungen sind gekennzeichnet durch Zellnekrosen sowie schwere Zell- und Kernschäden durch Eingriffe in die Zellkinetik, doch können diese auch spontan in unbehandelten anaplastischen Gliomen auftreten.Vergleichsuntersuchungen von zytologischen Abstrichen und histologischen Routinepräparaten an Biopsie- und Autopsiematerial von 4 Gruppen anaplastischer Astrozytome und Glioblastome (78 Fälle) wurden nach postoperativer Strahlenbehandlung, Polychemotherapie und CCNU-Behandlung sowie ohne spezifische postoperative Therapie (Kontrollgruppe) vorgenommen. Nach Strahlen- und Chemotherapie fanden sich neben gesteigerter Nekrose und Gefäßreaktion verschiedene charakteristische, aber unspezifische Zell- und Kernveränderungen mit gesteigerter Neigung zur Bildung vielkerniger Riesen- und Monsterzellen, Kernhyperchromasie sowie schwerer Zytoplasmadegeneration als Hinweise auf Mitosestörungen und Zellschädigung. Nach antineoplastischer Therapie fand sich eine statistisch signifikante Zunahme von Riesen- und vielkernigen Monsterzellen sowie Abnahme der Mitosen, wobei diese Veränderungen nach Chemotherapie stärker ausgeprägt waren als nach Bestrahlung. Zwischen Polychemo- und CCNU-Behandlung ergaben sich keine wesentlichen Abweichungen. Die Bedeutung dieser zytologischen Spätbefunde auf die Effekte antineoplastischer Behandlung anaplastischer Gliome wird diskutiert.
  相似文献   
10.
Summary Clinical and pathological features of an adult variant of adreno-leukodystrophy (ALD) are presented. A male with clinical and laboratory signs of Addison's disease (AD) developed at age 22 a slowly progressing paraplegia with slight sensory deficits in both legs and bladder and sphincter dysfunctions; he died at age 24 in an AD crisis. Autopsy revealed hyperplasia of lymphatic tissues, lymphocytic infiltrates in various organs including the CNS and adrenocortical atrophy with prominence of large ballooned, sometimes bizarre and occasionally striated cortical cells. CNS lesions consisted in incomplete demyelination of long tracts of brain stem and spinal cord with accentuation in the pyramical tracts; in these areas, perivascular cuffs of epitheloid histiocytic cells contained a strongly PAS-positive non-sudanophilic material. Electron microscopy demonstrated massive storage of leaflet structures in perivascular histiocytes identical to the lamellar profiles previously described as specific for ALD. Some leaflets were found in close contact with compact lamellar arrays and with an electron-dense fingerprint material within astrocytes.In our case, the spastic paraplegia-AD syndrome which has been described previously in several clinical observations could be neuropathologically classified as an adult variant of ALD. Several differences to classical ALD occurring in young boys are stressed: the predominance of the endocrine disorder probably accounting for some of the perivascular lymphocytic infiltrates within the CNS; the absence of both clinical and pathological signs of diffuse cerebral involvement and the peculiar topistic pattern of CNS lesions and the very slow evolution of neurological signs paralleled by the absence of active sudanophilic demyelinating lesions. The possible mechanism of demyelination and the nature of the suggested metabolic defect in ALD are discussed. The ultrastructurally prominent leaflet structures may originate from myelin remnants, thus relating ALD to pathological storage of a myelin degradation product.
Zusammenfassung Klinische und pathologische Befunde einer adulten Form der Adrenoleukodystrophie (ALD) werden dargestellt. Ein Patient mit klinischem Bild und Laboratoriumsbefunden der Addison-Krankheit (AD) entwickelte im Alter von 22 Jahren eine sehr langsam zunehmende Paraspastik mit geringer Hypaesthesie in beiden Beinen und Blasenund Mastdarmstörungen; er verstarb im Alter von 24 Jahren in einer AD-Krise. Bei der Autopsie fanden sich eine Hyperplasie des lymphatischen Apparats und lymphocytäre Infiltrate in verschiedenen Organen einschließlich des ZNS; beide Nebennieren waren atroph mit Hervortreten großer ballonierter, etwas bizarrer Rindenzellen mit gelegentlicher cytoplasmatischer Streifung. Im ZNS fanden sich pseudosystematische inkomplette Entmarkungen der langen Bahnen in Hirnstamm und Rückenmark mit Betonung der Pyramidenbahn, charakterisiert durch perivasale Manschetten epitheloider histiocytärer Zellen, die ein stark PAS-positives sudannegatives Material enthielten. Elektronenoptisch wurde eine massive Speicherung eines lamellären Materials in perivasalen Histiocyten nachgewiesen, welches mit den als spezifisch für die ALD angesehenen Einschlüssen übereinstimmte. Einige derartige Strukturen zeigten einen engen Zusammenhang mit kompakten Lamellenaggregaten und mit einem elektronendichten fingerprint-Material innerhalb von Astrocyten.In diesem Fall konnte das Paraplegie-AD-Syndrom, welches mehrfach bereits klinisch beschrieben worden war, aufgrund neuropathologischer Befunde als adulte Variante der ALD klassifiziert werden. Die Unterschiede dieser Form zur klassischen ALD, welche üblicherweise Knaben betrifft, werden hervorgehoben: das Überwiegen der endokrinen Symptomatik, was das Auftreten perivasaler Lymphocytensäume im ZNS zum Teil bedingen dürfte; das Fehlen klinischer und pathologischer Hinweise auf diffuse Beteiligung des Großhirns und die spezielle Topik der ZNS-Läsionen und die geringe Progredienz der neurologischen Symptomatik, welche im Einklang mit dem Fehlen florider sudanophiler Entmarkungsvorgänge steht. Der Mechanismus der Entmarkung und die Art der vermuteten metabolischen Störung bei der ALD werden diskutiert. Die elektronenoptisch charakteristischen lamellären Strukturen könnten aus dem Myelinabbau stammen, und damit könnte bei der ALD eine pathologische Speicherung eines Myelinabbauprodukts vorliegen.
  相似文献   
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