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11.
Review of imaging techniques for the diagnosis of breast cancer: a new role of prone scintimammography using technetium-99m sestamibi 总被引:6,自引:4,他引:2
Iraj Khalkhali Ismael Mena Linda Diggles 《European journal of nuclear medicine and molecular imaging》1994,21(4):357-362
Imaging techniques currently used for the diagnosis of breast cancer are reviewed and compared. Besides mammography, magnetic resonance imaging, positron emission tomography, and thallium-201 scintimammography, a new role of technetium-99m sestamibi scintimammography is discussed. It is concluded that while mammography remains the procedure of choice in screening asymptomatic women for breast cancer, other imaging methods play an important role in detecting malignancies in symptomatic patients.99mTc-sestamibi scintimammography has high sensitivity and improves the specificity of conventional mammography for the detection of breast cancer; with this technique, prone imaging is preferable to supine imaging.99mTc-sestamibi scintimammography thus deserves further study as a screening technique. 相似文献
12.
Pregnancy outcome associated with natural family planning (NFP): scientific basis and experimental design for an international cohort study 总被引:1,自引:0,他引:1
J. L. Simpson R. H. Gray J. T. Queenan P. Mena A. Perez R. T. Kambic G. Tagliabue F. Pardo W. S. Stevenson M. Barbato V. H. Jennings M. J. Zinaman J. M. Spieler 《Advances in Contraception》1988,4(4):247-264
Although natural family planning (NFP) is a form of contraception without ostensible maternal risks (other than pregnancy), potential fetal risks could exist if aging gametes are involved in inadvertent fertilization. In the following report, we first review animal studies firmly establishing that aging sperm and aging oocytes (delayed fertilization) cause chromosomal abnormalities in mammals and other species. We next review human studies associating decreased coital frequency with trisomy and studies of NFP populations that generally show no increased frequency of anomalous offspring or spontaneous abortions. Our rationale for initiating an international cohort study is presented, along with the experimental design selected. Preliminary findings indicate that the experimental design chosen will indeed provide information allowing NFP safety to be assessed definitively.
Resumen Aunque la planificación familiar natural (PFN) es una forma de anticoncepción sin riesgos maternos ostensibles, (fuera del embarzo) podrían existir posibles riesgos fetales di gametos que están envejeciendo son inadvertidamente fertilizados. La primera revisión de estudios en animales establece firmemente que espermatozoides y oocytos en envejecimiento (fertilización tardía), causan anormalidades cromosómicas en mamíferos y otras especies. A continuación revisamos estudios en humanos que asocian la disminución de la frecuencia coital con trisomía, y estudios de poblaciones practicando PFN que generalmente no muestran aumento en la frecuencia de descendientes anormales o de abortos espontáneos. Presentamos nuestras razones para iniciar el estudio de una cohorte internactional ademas del diseño experimental elegido proveerá información alegando que la inocuidad de la PFN sea definitivamente valorada.
Resumé Bien que le planning familial naturel (PFN-NFP) soit une forme de contraception ne présentant pas de risques manifestes pour la mère (autres qu'une grossesse), il pourrait y avoir des risques potentiels pour le foetus si des gamètes âgés sont par inadvertance fécondés. Nous passons en revue tout d'abord des études effectuées sur des animaux, établissant fermement que le sperme veillissant et les oocytes vieillissants (fécondation retardée) provoquent des anomalies chromosomales chez les mammifères et d'autres espèces. Nous examinons ensuite des études sur des humains, qui associent diminution coitale et trisomie, et des études de populations pratiquant le PFN, qui ne révèlent généralement pas de fréquence accrue d'enfants anormaux ou d'avortements spontanés. Cette communication expose la raison pour laquelle nous avons entrepris une étude sur une cohorte internationale, ainsi que le concept d'expérimentation que nous avons choisi. Les constatations préliminaires indiquent que ce concept fournira véritablement des informations qui permettront d'évaluer de façon définitive la sécurité du PFN.相似文献
13.
Francisco Camacho Juan Ferrando Antonio R. Pichardo Ismael Sotillo Enrique Jorquera 《Pediatric dermatology》1993,10(1):54-57
Abstract: A 20-year-old woman and her 12-year-old brother had hypohidrotic ectodermal dysplasia, cleft lip and palate, midfacial hypoplasia with narrow nose from the nasal bridge to the tip, narrow dysplastic nails, and conical teeth and hypodontia, and hypospadias and hypoplastic uvula in the boy. The woman had major underdevelopment of intellectual capacity. The most important hair anomalies in both siblings were sparse eyebrows, pili torti, and pili canaliculi. Some of the pili canaliculi had two canals (pili bicanaliculi), and the cross section for scanning electron microscopy had a quadrangular aspect. This is the seventh family reported with Rapp-Hodgkin ectodermal dysplasia. 相似文献
14.
E Mena F S Thompson A Y Armfield V R Dowell Jr D J Reinhardt 《Journal of clinical microbiology》1978,8(1):28-35
The protection of anaerobes in Port-A-Cul (PAC) transport system (Bioquest, Div. of Becton, Dickinson &Co., Cockeysville, Md.) tubes and vials was studied. Ten species of obligately anaerobic bacteria commonly isolated from clinical specimens were used to prepare simulated swab and fluid specimens in high and low concentrations. Samples in PAC tubes and vials were held for 2, 24, and 48 h at ambient temperature and in a refrigerator. In addition, samples of the simulated specimens were exposed to controlled anaerobic and aerobic conditions in vented tubes and vials, with and without PAC medium, at ambient and refrigerator temperatures. Viable bacterial colony counts from specimens in PAC tubes and vials used as recommended by the manufacturer were consistently greater than those from specimens exposed to the different controlled conditions. The protection in PAC was about equal for specimens with either high or low concentrations of bacteria. Protection of the anaerobes in PAC was more obvious with swab than with fluid specimens. Quantitative recovery of anaerobes from refrigerated PAC samples, with few exceptions, was comparable to that from PAC samples held at ambient temperature. 相似文献
15.
Valbuena JR Gualco G Espejo-Plascencia I Medeiros LJ 《Annals of diagnostic pathology》2005,9(1):38-42
We report a case of an 81-year-old immunocompetent Mexican man who underwent an abdominal-perineal rectal resection for a mass clinically thought to be carcinoma. Histopathologic diagnosis revealed classical Hodgkin lymphoma, nodular sclerosis type, involving the rectum. The diagnosis was confirmed by immunohistochemical studies that showed that the neoplastic cells were positive for CD15 and CD30 and negative for CD45 (LCA). In situ hybridization for Epstein-Barr virus small-encoded RNA was also positive in the neoplastic cells. Hodgkin lymphoma arising in the rectum of immunocompetent patients is rare, with only 12 cases (including this one) reported in the literature. Of these, the diagnosis was confirmed by immunohistochemical studies in only two cases, and this is the first case assessed and shown to be positive for Epstein-Barr virus. 相似文献
16.
Guzmán M Sánchez C Galve-Roperh I 《Journal of molecular medicine (Berlin, Germany)》2001,78(11):613-625
Cannabinoids, the active components of Cannabis sativa (marijuana), and their derivatives produce a wide spectrum of central and peripheral effects, some of which may have clinical application. The discovery of specific cannabinoid receptors and a family of endogenous ligands of those receptors has attracted much attention to cannabinoids in recent years. One of the most exciting and promising areas of current cannabinoid research is the ability of these compounds to control the cell survival/death decision. Thus cannabinoids may induce proliferation, growth arrest, or apoptosis in a number of cells, including neurons, lymphocytes, and various transformed neural and nonneural cells. The variation in drug effects may depend on experimental factors such as drug concentration, timing of drug delivery, and type of cell examined. Regarding the central nervous system, most of the experimental evidence indicates that cannabinoids may protect neurons from toxic insults such as glutamaergic overstimulation, ischemia and oxidative damage. In contrast, cannabinoids induce apoptosis of glioma cells in culture and regression of malignant gliomas in vivo. Breast and prostate cancer cells are also sensitive to cannabinoid-induced antiproliferation. Regarding the immune system, low doses of cannabinoids may enhance cell proliferation, whereas high doses of cannabinoids usually induce growth arrest or apoptosis. The neuroprotective effect of cannabinoids may have potential clinical relevance for the treatment of neurodegenerative disorders such as multiple sclerosis, Parkinson's disease, and ischemia/stroke, whereas their growth-inhibiting action on transformed cells might be useful for the management of malignant brain tumors. Ongoing investigation is in search for cannabinoid-based therapeutic strategies devoid of nondesired psychotropic effects. 相似文献
17.
Silvio S. Silva Ismael M. Mancilha Maurício A. Queiroz Maria G. A. Felipe Ines C. Roberto Michele Vitolo 《Journal of basic microbiology》1994,34(3):205-208
The xylose conversion into xylitol by Candida guilliermondii was evaluated in semi-synthetic media supplemented with different nitrogen sources in a ratio C/N equal 25.6. It was noticed that the xylitol yield was around 80% and also that the type of nitrogen source did not influence this bioconversion. 相似文献
18.
Coxsackievirus B3-Induced Myocarditis : Perforin Exacerbates Disease, But Plays No Detectable Role in Virus Clearance 总被引:8,自引:3,他引:8 下载免费PDF全文
John R. Gebhard Christopher M. Perry Stephanie Harkins Thomas Lane Ignacio Mena Valrie C. Asensio Iain L. Campbell J. Lindsay Whitton 《The American journal of pathology》1998,153(2):417-428
Viral myocarditis is remarkably common, being detected in approximately 1% of unselected asymptomatic individuals. Many cases are attributable to enteroviral infection, and in particular to coxsackievirus B3. The underlying pathogenesis is controversial, but most studies admit the important immunopathological role of infiltrating CD8+ (cytotoxic) T lymphocytes (CTLs). We have previously shown that CTLs play conflicting roles in coxsackievirus B (CVB) myocarditis; they assist in controlling virus replication, but also are instrumental in causing the extensive inflammatory disease, which often results in severe myocardial scarring. A role for perforin, the major CTL cytolytic protein, in CVB myocarditis has been suggested, but never proven. In the present study we use perforin knockout (PKO) mice to show that perforin plays a major role in CVB infection; in broad terms, perforin is important in immunopathology, but not in CVB clearance. For example, PKO mice are better able to withstand a normally lethal dose of CVB (100% survival of PKO mice compared with 90% death in +/+ littermates). In addition, PKO mice given a nonlethal dose of CVB develop only a mild myocarditis, whereas their perforin+ littermates have extensive myocardial lesions. The myocarditis in PKO mice resolves more quickly, and these mice show minimal histological sequelae; in contrast, late in disease the perforin+ mice develop severe myocardial fibrosis. PKO mice, despite lacking this major CTL effector function, can control the infection and eradicate the virus; growth kinetics and peak CVB titers are indistinguishable in PKO and perforin+ mice. Therefore, the immunopathological and antiviral effects of CTLs can be uncoupled by ablation of perforin; this offers a promising target for therapy of myocarditis. Furthermore, we evaluate the possible roles of apoptosis, and of chemokine expression, in CVB infection. In perforin+ mice, apoptotic cells are detected within the inflammatory infiltrate, whereas in their PKO counterparts, apoptotic myocyte nuclei are seen. Chemokine expression in both PKO and perforin+ mice precedes and parallels the course of myocarditis. Several chemokines are detectable earlier in PKO mice than in perforin+ mice, but PKO mice show reduced peak levels, and chemokine expression decays sooner. In particular, MIP-1α expression is barely detectable at any time point in PKO mice, but it is readily identified in perforin+ animals, peaking just before the time of maximal myocarditis; this is particularly interesting, given that MIP-1α knockout mice are resistant to CVB myocarditis, but remain able to control viral infection. Thus, the chemokine pathway offers a second route of intervention to diminish myocarditis and its sequelae, while permitting the host to eradicate the virus. 相似文献
19.
Rotavirus diarrhea severity is related to the VP4 type in Mexican children 总被引:6,自引:0,他引:6 下载免费PDF全文
Mota-Hernández F Calva JJ Gutiérrez-Camacho C Villa-Contreras S Arias CF Padilla-Noriega L Guiscafré-Gallardo H de Lourdes Guerrero M López S Muñoz O Contreras JF Cedillo R Herrera I Puerto FI 《Journal of clinical microbiology》2003,41(7):3158-3162
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas. 相似文献
20.