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101.
K. M. Mitchell R. J. Hale C. H. Buckley H. Fox D. Smith 《Virchows Archiv : an international journal of pathology》1993,422(5):357-360
An immunohistochemical study was made of cathepsin-D protein expression in each of the three main types of uterine cervical carcinoma (squamous carcinoma, adenosquamous carcinoma and adenocarcinoma) with particular reference to lymph node status and prognosis. Of the 61 cases, 54.1% showed cytoplasmic staining in more than 2.5% of tumour cells counted. Cathepsin-D expression was significantly higher in adenocarcinoma (mean -3.128) than in squamous carcinoma and adenosquamous carcinoma (mean –3.709,P=0.047 using logit transformation). Cathepsin-D had no prognostic value in any of the three tumour types. No relationship was found between cathepsin-D staining and lymph node status and there was no advantage in adding cathepsin-D values to lymph node status. These results suggest that immunostaining for cathepsin-D protein expression is unlikely to be of use as a prognostic marker. 相似文献
102.
With the increasing recognition of attention deficit hyperactivity disorder (ADHD) in adults and psychotic disorders in children and adolescents, the possibility of a relationship between bipolar disorder (BP) and ADHD has attracted growing interest. This paper critically reviews the scientific literature concerning this postulated relationship by examining evidence from clinico-epidemiological, follow up, family and laboratory studies, including neuroimaging, neuropsychology and genetic studies. The evidence suggests that although the diagnostic categories of BP and ADHD appear to be unrelated, there is support for a possible relationship between some ADHD and manic-like symptoms. However, several fundamental methodological issues require rectification in future research in order to further elucidate the relationship between these disorders. 相似文献
103.
Histamine is a known secretagogue in adrenal chromaffin cells. Activation of G-protein linked H(1) receptors stimulates phospholipase C, which generates inositol trisphosphate leading to release of intracellular calcium stores and stimulation of calcium influx through store operated and other channels. This calcium leads to the release of catecholamines. In chromaffin cells, the main physiological trigger for catecholamine release is calcium influx through voltage-gated calcium channels (I(Ca)). Therefore, these channels are important targets for the regulation of secretion. In particular N- and P/Q-type I(Ca) are subject to inhibition by transmitter/hormone receptor activation of heterotrimeric G-proteins. However, the direct effect of histamine on I(Ca) in chromaffin cells is unknown. This paper reports that histamine inhibited I(Ca) in cultured bovine adrenal chromaffin cells and this response was blocked by the H(1) antagonist mepyramine. With high levels of calcium buffering in the patch pipette solution (10 mM EGTA), histamine slowed the activation kinetics and inhibited the amplitude of I(Ca). A conditioning prepulse to +100 mV reversed the kinetic slowing and partially relieved the inhibition. These features are characteristic of a membrane delimited, voltage-dependent pathway which is thought to involve direct binding of G-protein betagamma subunits to the Ca channels. However, unlike virtually every other example of this type of inhibition, the response to histamine was not blocked by pretreating the cells with pertussis toxin (PTX). The voltage-dependent, PTX insensitive inhibition produced by histamine was modest compared with the PTX sensitive inhibition produced by ATP (28% vs. 53%). When histamine and ATP were applied concomitantly there was no additivity of the inhibition beyond that produced by ATP alone (even though the agonists appear to activate distinct G-proteins) suggesting that the inhibition produced by ATP is maximal. When experiments were carried out under conditions of low levels of calcium buffering in the patch pipette solution (0.1 mM EGTA), histamine inhibited I(Ca) in some cells using an entirely voltage insensitive pathway. We demonstrate that activation of PTX insensitive G-proteins (most likely Gq) by H(1) receptors inhibits I(Ca). This may represent a mechanism by which histamine exerts inhibitory (in addition to previously identified stimulatory) effects on catecholamine release. 相似文献
104.
Critical period for monocular deprivation in the cat visual cortex. 总被引:12,自引:0,他引:12
1. Cats were monocularly deprived for 3 mo starting at 8-9 mo, 12 mo, 15 mo, and several years of age. Single cells were recorded in both visual cortexes of each cat, and the ocular dominance and layer determined for each cell. Ocular dominance histograms were then constructed for layers II/III, IV, and V/VI for each group of animals. 2. There was a statistically significant shift in the ocular dominance for cells in layers II/III and V/VI for the animals deprived between 8-9 and 11-12 mo of age. There was a small but not statistically significant shift for cells in layer IV from the animals deprived between 8-9 and 11-12 mo of age, and for cells in layers V/VI from the animals deprived between 15 and 18 mo of age. There was no noticeable shift in ocular dominance for any other layers in any other group of animals. 3. We conclude that the critical period for monocular deprivation is finally over at approximately 1 yr of age for extragranular layers (layers II, III, V, and VI) in visual cortex of the cat. 相似文献
105.
Identification of Brucella by Ribosomal-Spacer-Region PCR and Differentiation of Brucella canis from Other Brucella spp. Pathogenic for Humans by Carbohydrate Profiles 总被引:3,自引:0,他引:3 下载免费PDF全文
Karen F. Fox Alvin Fox Madan Nagpal Paul Steinberg Karen Heroux 《Journal of clinical microbiology》1998,36(11):3217-3222
Molecular and chemical characteristics often provide complementary information in the differentiation of closely related organisms. The genus Brucella consists of a highly conserved group of organisms. Identification of the four species pathogenic in humans (Brucella melitensis, Brucella abortus, Brucella suis, and Brucella canis) is problematic for many clinical laboratories that depend primarily on serology and phenotypic characteristics to differentiate species. PCR amplification of the 16S-23S ribosomal DNA interspace region was evaluated for species-specific polymorphism. B. abortus, B. melitensis, B. suis, and B. canis produced identical PCR interspace profiles. However, these PCR products were unique to brucellae, allowing them to be readily distinguished from other gram-negative bacteria (including Bartonella spp. and Agrobacterium spp.). Carbohydrate profiles differentiated B. canis from the other three Brucella species due to the absence of the rare amino sugar quinovosamine in the three other species. PCR of the rRNA interspace region is useful in identification of the genus Brucella, while carbohydrate profiling is capable of differentiating B. canis from the other Brucella species. 相似文献
106.
F J Buckwold A R Ronald G K Harding T J Marrie L Fox C Cates 《Journal of clinical microbiology》1979,10(3):275-278
A nine-test system using multiple-inoculation agar plates for biotyping of Escherichia coli is described. Testing of 959 strains resulted in 78 biotypes. On repeated testing, 96% of 182 strains had identical biotypes or differed by only one test. This system provides satisfactory differentiation among strains and is reproducible. Precise standardization of inoculum size is not required. Multiple inoculation allows time and cost-efficient testing of large numbers of strains. 相似文献
107.
Zucker B Luthi-Carter R Kama JA Dunah AW Stern EA Fox JH Standaert DG Young AB Augood SJ 《Human molecular genetics》2005,14(2):179-189
108.
Detection of early antibodies in human immunodeficiency virus infection by enzyme-linked immunosorbent assay, Western blot, and radioimmunoprecipitation. 总被引:2,自引:11,他引:2 下载免费PDF全文
A J Saah H Farzadegan R Fox P Nishanian C R Rinaldo Jr J P Phair J L Fahey T H Lee B F Polk 《Journal of clinical microbiology》1987,25(9):1605-1610
A current concept of the serological response to human immunodeficiency virus (HIV) infection in humans is that antibodies to core antigens (p55, p24, and p15) are detectable earlier during initial stages of antibody production than antibodies against envelope antigens (gp160, gp120, and gp41). Comparative studies of Western blot (immunoblot), radioimmunoprecipitation assay (RIPA), and enzyme-linked immunosorbent assay (ELISA) during initial antibody production are limited to case reports and have not resolved the issue. Thirty of the 37 participants who are part of a prospective study had at least one specimen that was negative for anti-gp41 but had one or more other bands on Western blot. Twenty-seven of these 30 specimens were reactive for anti-gp120/160 in the RIPA. Of the same 30 specimens, kits from Bionetics identified 2 (7%), ElectroNucleonics 4 (13%), Abbott 13 (43%), Du Pont 25 (83%), and Genetic Systems 25 (83%). All participants had evidence of serological progression by Western blot, including a gp41 band, on subsequent visits; the ELISA kits of all manufacturers identified these later specimens with greater accuracy. These data show that the RIPA detects anti-envelope antibodies that may be not detectable by Western blot and that the production of anti-envelope antibodies approximately parallels the production of anti-core antibodies. The false-negative results by ELISA would permit transmission of HIV by blood transfusion from donors in early stages of infection. The sensitivity of licensed ELISA kits should be improved to identify antibody as soon as possible after infection. 相似文献
109.
An epidemiologically valuable typing method for Neisseria meningitidis by analysis of restriction fragment length polymorphisms. 总被引:1,自引:0,他引:1
A J Fox D M Jones S J Gray D A Caugant N A Saunders 《Journal of medical microbiology》1991,34(5):265-270
A restriction fragment length polymorphism (RFLP) typing method was developed for Neisseria meningitidis. A cloned EcoRI fragment from a Neisseria meningitidis Group B serotype 15P1.16 sulphonamide-resistant strain was used to probe Southern blots of total chromosomal DNA restriction fragments (enzyme AvaI). A group of 75 apparently unrelated organisms gave rise to 26 different restriction fragment length patterns and two different groups of epidemiologically related strains had RFLP patterns that were distinct for each group. The technique was highly reproducible and discriminatory. The RFLP data were compared with the results of serotyping and subtyping and isoenzyme electrophoretotyping. The RFLP data were consistent with those from the alternative typing methods; clones defined by isoenzyme analysis were subdivided by this technique. The use of RFLP typing by cloned probes should be of considerable epidemiological value. 相似文献
110.
Bipolar women have a marked vulnerability to puerperal psychosis, an episode of mania or psychosis following childbirth. We have conducted a family history study to examine the question of whether a vulnerability to puerperal episodes of illness is a marker for a more familial form of bipolar disorder. A consecutive series of 103 bipolar disorder probands were recruited in a lithium clinic and given a semi-structured interview, including a detailed family history. For the 52 female probands, information was also obtained about the relationship of episodes to childbirth. The morbid risk of affective disorder in first-degree relatives of bipolar women who had suffered an episode of mania, hypomania or schizoaffective mania with onset within 6 weeks of childbirth was significantly higher than that in relatives of parous bipolar women with no episodes in relation to childbirth (P = 0.0077). Despite relatively small numbers, this study provides evidence to support the hypothesis that puerperal episodes identify a more familial subtype of bipolar disorder. 相似文献