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991.
Trivial head trauma may be complicated by severe, sometimes even fatal, cerebral edema and coma occurring after a lucid interval ("delayed cerebral edema"). Attacks of familial hemiplegic migraine (FHM) can be triggered by minor head trauma and are sometimes accompanied by coma. Mutations in the CACNA1A calcium channel subunit gene on chromosome 19 are associated with a wide spectrum of mutation-specific episodic and chronic neurological disorders, including FHM with or without coma. We investigated the role of the CACNA1A gene in three subjects with delayed cerebral edema. Two subjects originated from a family with extreme FHM, and one subject was the previously asymptomatic daughter of a sporadic patient with hemiplegic migraine attacks. In all three subjects with delayed severe edema, we found a C-to-T substitution resulting in the substitution of serine for lysine at codon 218 (S218L) in the CACNA1A gene. The mutation was absent in nonaffected family members and 152 control individuals. Haplotype analysis excluded a common founder for both families. Neuropathological examination in one subject showed Purkinje cell loss with relative preservation of granule cells and sparing of the dentate and inferior olivary nuclei. We conclude that the novel S218L mutation in the CACNA1A calcium channel subunit gene is involved in FHM and delayed fatal cerebral edema and coma after minor head trauma. This finding may have important implications for the understanding and treatment of this dramatic syndrome.  相似文献   
992.
993.
A 68-year-old man presented with obstructive and irritative lower urinary tract symptoms and microscopic hematuria. Cystourethroscopy showed a circumferential stricture in the bulbar urethra that bled easily on contact. Biopsy revealed malacoplakia. There was also focal nonspecific cystitis. The patient improved symptomatically, but the microscopic hematuria persisted. Follow-up biopsies showed persistent urethral malacoplakia and stricture. Malacoplakia of the male urethra is exceptionally rare, this being the second reported case.  相似文献   
994.
背景侵袭性B细胞淋巴瘤是目前最常见的非霍奇金淋巴瘤类型,主要包括弥漫大B细胞淋巴瘤(DLBCL)和套细胞淋巴瘤(MCL)。超过60%的患者被诊断出B细胞淋巴瘤时年龄都在60岁以上。在过去的30年间,CHOP方案(环磷酰胺、多柔比星、长春新碱、泼尼松)是治疗DLBCL的金标准。年龄较轻的患者  相似文献   
995.
The relationship between amyloid beta-protein (A beta) length and the apolipoprotein E (APOE) epsilon 2 allele, which is over-represented in cerebral amyloid angiopathy-related haemorrhage (CAAH), has not previously been examined. Of 57 CAA patients studied, 37 had CAAH. All patients, particularly those with CAAH had more blood vessels immunoreactive for A beta 40 than A beta 42 in both the leptomeninges and cerebral cortex. CAAH patients had more A beta 40-immunoreactive blood vessels in the leptomeninges (p < 0.001) and cortex (p = 0.027) than had non-haemorrhage patients. Cortical blood vessels, the usual source of haemorrhage in CAAH, were more frequently A beta 42 immunoreactive in APOE epsilon 2 carriers than in non-epsilon 2 carriers (p = 0.022). The APOE epsilon 2 allele may predispose to CAAH by increasing the seeding of cortical blood vessels by A beta 42.  相似文献   
996.
Role of nuclear medicine in diagnosis of the infected joint replacement.   总被引:10,自引:0,他引:10  
Some complications of joint replacement surgery are easily diagnosed; however, differentiating infection from aseptic loosening is difficult because these entities are remarkably similar at clinical and histopathologic examination. Clinical signs and symptoms, laboratory tests, radiography, and joint aspiration are insensitive, nonspecific, or both. Cross-sectional imaging modalities are hampered by artifacts produced by the prosthetic devices themselves. Radionuclide imaging is not affected by the presence of metallic hardware and is therefore useful for evaluating the painful prosthesis. Bone scintigraphy is useful as a screening test, despite an accuracy of only 50%-70%, because normal results essentially exclude a prosthetic complication. The addition of gallium-67, a nonspecific inflammation-imaging agent, improves the accuracy of bone scintigraphy to 70%-80%. The accuracy of combined leukocyte-marrow imaging, 90%, is the highest among available radionuclide studies. Its success is due to the fact that leukocyte imaging is most sensitive for detection of neutrophil-mediated inflammation (ie, infection). The success of leukocyte-marrow imaging is tempered by the limitations of in vitro labeling. In vivo labeling has been investigated, and a murine monoclonal antigranulocyte antibody appears promising. Some investigations have focused on fluorodeoxyglucose imaging. Although this method is sensitive, specificity is a concern.  相似文献   
997.
998.
PurposeTo define the effect of sperm agglutination, associated with incubation under capacitating conditions, on accuracy of membrane assessment via flow cytometry and to develop methods to mitigate that effect.MethodsSperm motility was measured by CASA. Sperm were stained with PI-PSA or a novel method, LD-PSA, using fixable live/dead stain and cell dissociation treatment, before flow-cytometric analysis. Using LD-PSA, acrosome reaction and plasma membrane status were determined in equine sperm treated with 10 μm A23187 for 10 min, followed by 0, 1, or 2 h incubation in capacitating conditions.ResultsUsing PI-PSA, measured membrane integrity (MI; live sperm) was dramatically lower than was total motility (TMOT), indicating spurious results (“zombie sperm”). Sperm aggregates were largely of motile sperm. Loss of motility after A23187 treatment was associated with disaggregation and increased MI. On disaggregation using LD-PSA, MI rose, and MI then corresponded with TMOT. In equine sperm incubated after A23187 treatment, as the percentage of live acrosome-reacted sperm increased, TMOT decreased to near 0.ConclusionFlow cytometry assesses only individualized sperm; thus, agglutination of viable sperm alters recorded membrane integrity. As viable sperm become immotile, they individualize; therefore, factors that decrease motility, such as A23187, result in increased measured MI. Disaggregation before assessment allows more accurate determination of sperm membrane status; in this case we documented a mismatch between motility and live acrosome-reacted equine sperm that may relate to the poor repeatability of A23187 treatment for equine IVF. These findings are of profound value to future studies on sperm capacitation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10815-021-02134-z.  相似文献   
999.
There are few treatment options for prostate cancer once it becomes hormone refractory, with a mean life expectancy of 9-12 months. During the period 1997-2002, a product known as PC-Spes, containing a mixture of extracts from eight herbs based on the principles of traditional Chinese medicine, was reported to inhibit prostate cancer cell growth in vitro and reduce PSA in patients with hormone refractory prostate cancer (HRPC). This product was withdrawn from the market in 2002 due to concerns over quality control and reported contamination with traces of warfarin, indomethacin and diethylstilbesterol. PC-spes2, manufactured by Active Botanicals Ltd. (UK) with strict, independently-conducted quality control, has demonstrated no contaminants by high pressure liquid chromatography and liquid chromatography/mass spectroscopy. This compound was investigated in a single-centre, prospective, open pilot study. Eighteen patients with HRPC, mean age 72, median Gleason sum 8 (range 4-9) and median PSA 110 (range 4-2870) with three consecutive monthly increases in PSA were studied. Ten patients withdrew during the study period with significant diarrhoea (8 out of the first 10 patients at one month and only 2 out of the last 8 due to an improved dosing schedule). At one month, 7 out of 10 patients had a drop in their PSA doubling time or PSA velocity, which was still apparent in 4 out of 5 patients still on trial at three months and all three patients still on trial at six months. No serious adverse events or derangement of coagulation were observed. PC-Spes2 offers renewed hope and a safe alternative treatment option for patients with advanced HRPC. Further investigation with phase II trials is warranted.  相似文献   
1000.
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