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71.
This review examines the evidence that a subset of patients with breast cancer have tumors that are stimulated to grow by host cells in the tumor stroma. The search for such a minority group was prompted by the following observations. Adjuvant chemotherapy which is immunosuppressive improves disease-free interval and survival, whereas non-specific immunostimulation worsens the prognosis. Intrinsic immune reactivity is associated with a poor prognosis. A subset of tumors with a bad prognosis has anaplastic cells, dermal lymphatic invasion and a moderate to intense lymphoplasmacytic stromal infiltrate. Evidence is reviewed that adjuvant chemotherapy may be beneficial by virtue of its immunosuppressive effects in addition to tumor kill of minimal residual disease. 相似文献
72.
Vandellia cordifolia (COLSM) G. DON of Scrophulariaceae (V. cordifolia) is an annual wild herb indigenous to Taiwan. It can be found in plains, low altitudes, swampy places, and paddy fields. Taiwanese folk physicians use it in "nephritis, uremia, furnucle, carbuncle." The LD50 (95% confidence limit) of the crude extract of V. codifolia given by the oral route was more than 10 g/kg in rats. By the intraperitoneal route, it was 4.6 g/kg (4.35-4.93). The extraction rate was 16.6%. We studied its effects on renal functions and blood pressure and found that (1) it had diuretic effect on normal rats, (2) it decreased glomerular filtration rate and renal blood flow on normal kidneys in rabbits, (3) it had no effects on glomerular filtration rate and renal blood flow on glycerin-induced insufficient kidneys in rabbits, (4) it had diuretic effects on both normal and glycerin-induced insufficient kidneys in rabbits, (5) it could inhibit Na+ and K+ reabsorption on normal and glycerin-induced insufficient kidneys in rabbits, (6) it had hypertensive effect and this effect could be blocked by phenoxybenzamine. From the above facts, we conclude that V. cordifolia has diuretic effect and it may act on renal tubules to inhibit Na+ and K+ reabsorption. 相似文献
73.
In some individuals, breathing is greater than at rest following voluntary hyperventilation. Most previous investigations have employed short hyperventilation periods; here we examine the time course of cardio-respiratory measures before, during, and after a 5-min voluntary hyperventilation, maintaining isocapnia throughout. We examined the possible co-involvement of the cardiovascular system; hypothesising that post-hyperventilation hyperpnoea results from an increase in autonomic arousal. In four subjects (two males, two females) of 18 (nine males, nine females) we observed a post-hyperventilation hyperpnoea, characterised by a slow decline of ventilation toward resting levels with a time constant of 109.0 +/- 16.1s. By contrast, heart rate, and systolic and diastolic blood pressure were unchanged from rest during and after voluntary hyperventilation for all subjects. We concluded that males and females were equally likely to exhibit post-hyperventilation hyperpnoea, and suggest that they may be characterised by an increased resting heart rate and the choice of breathing frequency to increase ventilation during the voluntary hyperventilation. We further concluded that post-hyperventilation hyperpnoea is rare, but when present is a strong and lasting phenomenon, and that it is not the result of an increased autonomic arousal. 相似文献
74.
Physical and biological properties of U.S. standard endotoxin EC after exposure to ionizing radiation. 下载免费PDF全文
Techniques that reduce the toxicity of bacterial endotoxins are useful for studying the relationship between structure and biological activity. We used ionizing radiation to detoxify a highly refined endotoxin preparation. U.S. standard endotoxin EC. Dose-dependent changes occurred by exposure to 60Co-radiation in the physical properties and biological activities of the endotoxin. Sodium dodecyl sulfate-polyacrylamide slab gel electrophoresis showed gradual loss of the polysaccharide components (O-side chain and R-core) from the endotoxin molecules. In contrast, although endotoxin revealed a complex absorption pattern in the UV range, radiation treatment failed to modify that pattern. Dose-related destruction of the primary toxic component, lipid A, was suggested by the results of activity tests: both the pyrogenicity and limulus reactivity of the endotoxin were destroyed by increasing doses of radiation. The results indicate that the detoxification is probably due to multiple effects of the ionizing radiation on bacterial lipopolysaccharides, and the action involves (i) the destruction of polysaccharide moieties and possibly (ii) the alteration of lipid A component of the endotoxin molecule. 相似文献
75.
Inherited chondrodysplasia punctata due to a deletion of the terminal short arm of an X chromosome 总被引:27,自引:0,他引:27
C J Curry R E Magenis M Brown J T Lanman J Tsai P O'Lague P Goodfellow T Mohandas E A Bergner L J Shapiro 《The New England journal of medicine》1984,311(16):1010-1015
We studied two families with an inherited deletion of the short arm of an X chromosome (Xp) in which affected male offspring have epiphyseal stippling in infancy (chondrodysplasia punctata), nasal hypoplasia, ichthyosis, and mental retardation. The presence of ichthyosis and the apparent pattern of X-linked recessive inheritance prompted investigation of the short arm of the X chromosome through studies of genetic markers and focused cytogenetic analysis. Biochemical studies suggested that there was a deletion of three genes previously mapped to the X-chromosome short arm, including the steroid sulfatase locus, the Xg locus, and the M1C2X locus. Prometaphase chromosomes demonstrated a deletion of Xp at p22.32 in the affected boys, in their obligate-carrier mothers, and in 11 of 25 women at risk as potential carriers. The women carrying the Xp deletion had normal gonadal function and fertility but were shorter than the noncarriers in their families (P less than 0.00001). These findings have implications for the genetic organization of this portion of the human X chromosome and demonstrate that small cytogenetic abnormalities may account for disorders with apparent mendelian patterns of inheritance. 相似文献
76.
Chou-Lang Huang Yao-Hsu Yang Li-Chieh Wang Yu-Tsan Lin Yu-Yuan Tsai Bor-Luen Chiang 《Journal of microbiology, immunology, and infection》2005,38(3):169-175
Measles immunoglobulin G (IgG) seroepidemiologic studies have been widely used to monitor the effectiveness of measles immunization programs in Taiwan. However, studies about cellular immunity against the measles virus have been lacking. This study surveyed cellular immunity after measles, mumps and rubella combined vaccine (MMR) immunization in Taiwan. Seventy six people between 1 and 80 years of age were enrolled. All patients lived in northern Taiwan, and none of them had immunodeficient disease. Every enrolled patient donated a tube of heparinized blood between January 2004 and June 2004 for cross-sectional studies of IgG seroepidemiologic and MMR-specific lymphoproliferative response. The results showed that the current 3-dose (measles x 1 + MMR x 2) measles immunization program induced slightly higher IgG seroprevalence (100% vs 85%, p=0.244) and a higher frequency of significant (stimulation indices > or = 3) MMR-specific lymphoproliferative response (50% vs 15%, p=0.044) than a 2-dose (measles x 1 + MMR x 1) immunization program, although there was no difference in IgG titers and stimulation indices. Furthermore, the population aged older than 36 years (pre-immunization era) had higher IgG titers and seroprevalence, and similar MMR-specific lymphoproliferative responses to that of the population aged younger than 36 years (post-immunization era). In summary, with the limited data, the current 3-dose (measles x 1 + MMR x 2) measles immunization policy probably more effectively induces humoral and cellular immunity than the 2-dose (measles x 1 + MMR x 1) policy. Measles IgG seroprevalence in populations of different age groups exceeds nearly 90%. Measles has been eliminated temporarily in Taiwan. For a better understanding of the durability of vaccine-induced immunity and in order to establish the most appropriate immunization schedule, long-term and large-scale prospective studies of measles-specific seroepidemiology and cellular immunity will be needed. 相似文献
77.
Mindy Tsai Rey-Huei Chen See-Ying Tam John Blenis Stephen J. Galli 《European journal of immunology》1993,23(12):3286-3291
The high-affinity receptor for IgE, Fc?RI, represents the major cell surface structure through which mast cells express immunologically specific secretory function. By contrast, the stem cell factor receptor (SCFR), which is encoded by c-kit, is essential for normal mast cell development. The signaling pathways initiated by the stimulation of mast cells through the Fc?RI, which lacks intrinsic kinase activity, and the SCFR, a member of the receptor tyrosine kinase family, generally have been regarded to be distinct. We report here that mouse mast cells stimulated either with SCF or with IgE and specific antigen exhibit a remarkably similar pattern of activation of mitogen-activated protein kinases (MAPK), 90 kDa-S6 kinases (pp90rsk), and pp70-S6 kinases (pp70-S6K). These results indicate that all three families of protein kinases are associated with the cell surface receptor-dependent activation of secretion, as well as proliferation, in mast cells. We also show that the immunosuppressant rapamycin, but not FK506, can inhibit both SCF-dependent pp70-S6 kinase activation and SCF-dependent proliferation in mouse mast cells, without suppressing IgE- and antigen-dependent mediator release. These findings suggest that the activation of pp70-S6 kinase represents an important link in the stimulation of cell proliferation by SCF. Our results also indicate that the intracellular signaling pathways initiated by stimulation of mast cells through the Fc?RI or the SCFR exhibit more overlap than has previously been appreciated. 相似文献
78.
Parallel genotyping of over 10,000 SNPs using a one-primer assay on a high-density oligonucleotide array 总被引:18,自引:1,他引:18 下载免费PDF全文
Matsuzaki H Loi H Dong S Tsai YY Fang J Law J Di X Liu WM Yang G Liu G Huang J Kennedy GC Ryder TB Marcus GA Walsh PS Shriver MD Puck JM Jones KW Mei R 《Genome research》2004,14(3):414-425
The analysis of single nucleotide polymorphisms (SNPs) is increasingly utilized to investigate the genetic causes of complex human diseases. Here we present a high-throughput genotyping platform that uses a one-primer assay to genotype over 10,000 SNPs per individual on a single oligonucleotide array. This approach uses restriction digestion to fractionate the genome, followed by amplification of a specific fractionated subset of the genome. The resulting reduction in genome complexity enables allele-specific hybridization to the array. The selection of SNPs was primarily determined by computer-predicted lengths of restriction fragments containing the SNPs, and was further driven by strict empirical measurements of accuracy, reproducibility, and average call rate, which we estimate to be >99.5%, >99.9%, and>95%, respectively [corrected]. With average heterozygosity of 0.38 and genome scan resolution of 0.31 cM, the SNP array is a viable alternative to panels of microsatellites (STRs). As a demonstration of the utility of the genotyping platform in whole-genome scans, we have replicated and refined a linkage region on chromosome 2p for chronic mucocutaneous candidiasis and thyroid disease, previously identified using a panel of microsatellite (STR) markers. 相似文献
79.
Detection of St. Louis encephalitis virus antigen in mosquitoes by capture enzyme immunoassay. 总被引:1,自引:4,他引:1 下载免费PDF全文
T F Tsai R A Bolin M Montoya R E Bailey D B Francy M Jozan J T Roehrig 《Journal of clinical microbiology》1987,25(2):370-376
Surveillance methods that measure St. Louis encephalitis (SLE) virus activity in nature may provide forewarning of its epidemic occurrence in humans. An antigen capture enzyme immunoassay was developed to detect SLE virus in infected mosquitoes. The assay detected purified SLE viral antigen at a concentration of 62 pg/0.1 ml when antigen was incubated overnight; 250 pg/0.1 ml was detected in a single-day assay (antigen incubated for 3 h). The assay detected 67.9 and 70.8% of laboratory-prepared pools of infected mosquitoes after 3 h and overnight incubation, respectively. The sensitivity of the procedure was 90.5% in identifying pools with infectious titers greater than dex 3.0. The specificity of the assay was controlled by retesting positive pools preincubated with SLE virus and normal antibodies, which led to a diminution of signal in the pools containing viral antigen. The procedure was suitably specific in discriminating between SLE and related flaviviruses, detecting only high infectious doses of heterologous antigens. 相似文献
80.
We present a family consisting of a mother, a daughter, and a son with Teebi hypertelorism syndrome, including some previously unrecognized manifestations. The clinical findings include a prominent forehead, arched eyebrows, pronounced hypertelorism, long philtrum, mild interdigital webbing, fifth-finger clinodactyly, umbilical anomalies, and hypotonia. The mother and daughter also had ptosis requiring surgical correction. The daughter has bilateral iridochorioretinal colobomas with high hyperopia and a small umbilical hernia. The son has less striking facial features but was born with a small omphalocele, large ASD secundum, PDA, bilateral cryptorchidism right hydronephrosis, and a cystic left kidney. The mother had an umbilical hernia requiring surgical correction as a child and a history of heart murmur. Both children have normal hearing and mild developmental delay. Their high-resolution karyotypes were normal and the FISH for 22q11 microdeletion was negative in the daughter. We conclude that cardiac defects in Teebi hypertelorism syndrome are not rare findings and that eye colobomas and renal anomalies were previously unrecognized. 相似文献