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81.
Correct histopathologic diagnosis is essential for adequate treatment of soft tissue sarcomas. Due to the disorder’s rarity, multitude of subgroups, sometimes varying histopathologic appearance, and occasionally inadequate biopsy specimens, diagnosis and grading are challenging. The records of 603 patients with soft tissue tumors of the extremities were reviewed concerning mismatches in primary and definite diagnoses relating to entity, evaluation of primary or recurrent tumor specimens, and the diagnosing pathology institution. For second opinions we referred to the Institute of Pathology of the Ruhr University at the Bergmannsheil Hospital in Bochum, Germany, and to the Pathology Institute of the University of Jena, also in Germany. Liposarcoma and malignant fibrous histiocytoma were the most often diagnosed subgroups at 24% and 22.6%, respectively. In the eight most frequent sarcoma types, malignant peripheral nerve sheath tumors and leiomyosarcoma had the highest rates of false primary diagnosis, 78.4% and 74.2% of cases, respectively. The diagnostic error ratio for nonspecialized pathologists in practice, community hospital pathologists, and academic medical centers was over 60%. For optimal treatment of soft tissue sarcomas, we suggest obtaining expert second opinion to ensure adequate surgical therapy and precise indications for radiation and chemotherapy.  相似文献   
82.
Self-assembly of the 40/42 amino acid Abeta peptide is a key player in Alzheimer's disease. Abeta40 is the most prevalent species, while Abeta42 is the most toxic. It has been suggested that the amino acids 21-30 could nucleate the folding of Abeta monomer and a bent in this region could be the rate-limiting step in Abeta fibril formation. In this study, we review our current understanding of the computer-predicted conformations of amino acids 23-28 in the monomer of Abeta(21-30) and the monomers Abeta40 and Abeta42. On the basis of new simulations on dimers of full-length Abeta, we propose that the rate-limiting step involves the formation of a multimeric beta-sheet spanning the central hydrophobic core (residues 17-21).  相似文献   
83.
BACKGROUND: Pain is a dynamic phenomenon resulting from the activity of both excitatory (e.g. sensitization) and inhibitory endogenous modulation systems. Preliminary experimental studies have shown diminished pain sensitivity in schizophrenia patients. The objective of the study was to investigate the role of excitatory and inhibitory systems on pain perception in schizophrenia. METHODS: Participants were 23 patients with a schizophrenia-spectrum disorder (DSM-IV criteria) and 29 healthy volunteers, who did not differ in age, sex or ethnicity. Excitatory and inhibitory systems were elicited using a temporal summation test (Peltier thermode) administered before and after activation of the diffuse noxious inhibitory control (DNIC) by means of a cold-pressor test. RESULTS: Time was a significant predictor of pain scores in controls, but not in patients. That is, pain ratings increased during the tonic thermal stimulation among controls but not in schizophrenia patients. When correlation coefficients (between time and pain ratings) for patients and controls were compared, the correlation coefficient emerged as significantly weaker in the schizophrenia group (Z=12.04; p=0.0001), suggesting a lack of sensitization in schizophrenia. DNIC was similar in magnitude in both patients and controls. CONCLUSIONS: Diminished pain sensitivity in schizophrenia may be related to abnormal excitatory mechanisms, but not to DNIC. More studies are needed to better characterize the neurophysiological and neurochemical mechanisms involved in the lack of sensitization in schizophrenia.  相似文献   
84.
The parasite Toxoplasma gondii mainly encysts in brain, retina, myocardium, and skeletal muscle. It has been implicated in the genesis of inflammatory myopathies for years, but the parasite usually cannot be detected in the muscle. It is established, however, that toxoplasmosis can cause myositis either by recent infection or by reactivation. The case of a non-HIV patient who developed an acute polymyositis upon infection by T. gondii is reported. We suggest that all patients with polymyositis should have serological tests for toxoplasmosis as a part of their initial evaluation and early trial of antiprotozoal therapy in case of positive findings.  相似文献   
85.
IntroductionKaryotyping is often performed in transsexual individuals.AimQuantification and characterization of karyotype findings and abnormalities in transsexual persons.Main Outcome MeasuresKaryotypes were listed both in male‐to‐female and in female‐to‐male transsexual persons.MethodsThe data were collected through a retrospective study.ResultsKaryotypes of 368 transsexual individuals (251 male‐to‐female, 117 female‐to‐male) are described. Normal findings were found in 97.55%. Prevalence of abnormal karyotypes was 3.19% among male‐to‐female, and 0.85% among female‐to‐male transsexuals. Nine karyotypes showed variations; Klinefelter syndrome was confirmed in three persons, whereas others displayed autosomal aberrations.ConclusionKaryotyping is only of very limited information in the transsexual population. Inoubli A, De Cuypere G, Rubens R, Heylens G, Elaut E, Van Caenegem E, Menten B, and T'Sjoen G. Karyotyping, is it worthwhile in transsexualism?  相似文献   
86.
87.
This trial aimed to assess the value of MRI in the differential diagnosis of chronic groin pain in athletes, a condition caused by various pathologies, the most common being posterior abdominal wall deficiency, osteitis pubis and muscular imbalance. Nineteen subjects with clinically ruled-out hernia and recurrent episodes of exercise-triggered groin pain were assessed. Dynamic MRI was performed under Valsalva manoeuver and at rest within a training- free period and after training activity. Follow-up was performed after 4 years using a questionnaire and physical examination. An incipient hernia was seen in one case, Valsalva manoeuver provoked a visible bulging in 7 others (3 bilateral). Eight athletes showed symphysitis (accompanied by bulging in 3 cases). MRI visualized one hydrocele, one osteoma of the left femur, one enchondroma of the pubic bone, and one dilated left ureter without clinical symptoms or therapeutic relevance. MRI findings after training and during the training free period did not vary. Fifteen participants were available for a follow-up control examination 4 years later - one suffered from ongoing pain, eleven were free of symptoms and three had improvement. However, most of them improved only with changing or reducing training. There were four participants with a specific therapy of their MRI findings. MRI revealed a variety of pathological findings in athletes suffering from chronic groin pain, but it was not reliable enough in differentiating between diagnoses requiring conservative or operative treatment. The MRI examination within the training interval did not have an advantage to that within the training-free period. Further randomized prospective trials with a long follow-up should establish whether MRI findings could be of help in the choice between conservative and surgical treatment for chronic groin pain.

Key points

  • MRI findings after training and during the train free period did not vary.
  • MRI revealed a variety of pathological findings in athletes suffering from chronic groin pain, but it was not reliable enough in differentiating between diagnoses requiring conservative or operative treatment.
Key words: MRI, hernia, athletes, chronic groin pain, symphysitis  相似文献   
88.
89.
Data on acute chest syndrome (ACS) in adult sickle cell disease patients are scarce. In this study, we describe 105 consecutive ACS episodes in 81 adult patients during a 32-month period and compare the characteristics as a function of the time to onset after hospital admission for a vaso-occlusive crisis (VOC), that is early-onset episodes (time to onset ≤24 h, 42%) versus secondary episodes (>24 h, 58%; median [interquartile range] time to onset: 2 [2–3] days). The median age was 27 [22–34] years, 89% of the patients had an S/S or S/β0-thalassaemia genotype; 81% of the patients had a history of ACS (median: 3 [2–5] per patient), only 61% were taking a disease-modifying treatment at the time of the ACS. Fever and chest pain were noted in respectively 54% and 73% of the episodes. Crackles (64%) and bronchial breathing (32%) were the main abnormal auscultatory findings. A positive microbiological test was found for 20% of episodes. Fifty percent of the episodes required a blood transfusion; ICU transfer and mortality rates were respectively 29% and 1%. Secondary and early-onset forms of ACS did not differ significantly. Disease-modifying treatments should be revaluated after each ACS episode because the recurrence rate is high.  相似文献   
90.
Eight outbreaks of acute and subacute fasciolosis are reported in sheep in the municipality of Santa Vitória do Palmar, southern Brazil, in areas used for irrigated rice cultivation, which are subject to frequent flooding. Two outbreaks occurred mid-winter during July and August, and six occurred during spring and early summer. Morbidity ranged from 3 to 66.7 %, and mortality ranged from 3 to 50 %. Clinical signs included weight loss, mucosal pallor, apathy, depression, muscle tremors, and drooling; these were followed by death within approximately 24 h. Some sheep were found dead. Gross lesions were characterized by an irregular liver capsule with fibrin deposition and hemorrhages. The liver parenchyma contained hemorrhagic tracts or irregular clear areas alternated with dark hemorrhagic areas. Histologically, hemorrhagic dark red tracts of necrotic liver parenchyma and an inflammatory infiltrate were noted; these lesions coincided with the presence of immature flukes. Langhans-type giant cells, fibrous tissue, and bile duct cell proliferation were observed in subacute cases. Chronic fasciolosis is a well-known disease to farmers in southern Brazil; nevertheless, acute and subacute fasciolosis, which are more difficult to diagnose and treat, may cause important economic losses. Efficient control of fasciolosis requires integration of measures to treat infections in the definitive host, to reduce the population of snails of the genus Lymnaea, and to avoid contact between the parasite and host by appropriate pasture management.  相似文献   
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