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81.
The aim of this study was to compare the efficacy of pure follicle stimulating hormone (FSH) with that of FSH/human menopausal gonadotrophin (HMG) combination in downregulated cycles. A total of 357 patients was evaluated retrospectively. Sixty percent of patients in the FSH group and 55% in the FSH/HMG group were new; the others were repeat patients. Ovulation was suppressed with leuprolide acetate in all patients, followed by either FSH (n = 218) or FSH/HMG (n = 119). There was no difference in patients' age, infertility factors, number of ampoules used, length of stimulation, oestradiol levels on day of human chorionic gonadotrophin (HCG) administration, number of oocytes recovered or the number of embryos transferred. Also, nuclear maturity at aspiration and fertilization rates were not different between the two groups. FSH stimulation resulted in a significantly higher percentage of mature oocytes that showed the typical 'mature' morphological characteristics (P < 0.0001). The clinical pregnancy rates per transfer were 40 and 28% in patients stimulated with pure FSH and FSH/HMG respectively (P < 0.05). The significantly higher number of immature oocytes matured in vitro in the FSH/HMG group (P = 0.001) suggests a possible effect on in-vitro maturation, due to luteinizing hormone present in HMG. The difference in mature oocyte quality may be an important determinant in the higher pregnancy rates for the FSH- stimulated patients.   相似文献   
82.
Using trypsin Giemsa banding (GTG), major polymorphisms of the constitutive heterochromatin regions of chromosome 1, 9, 16, and Y were recorded in a New York City population. Polymorphisms were recorded from amniotic fluid specimens received from 6,250 patients from 4 major population groups, ie, White (European)-2,334 cases, American Black-1,795 cases, Hispanic descent-1,737 cases, and Asian (Oriental and Indian)-384 cases. The major chromosomal polymorphisms were classified as follows: obvious pericentric inversion of the constitutive heterochromatin of the long arm of the chromosome (inv qh); significantly enlarged heterochromatic region of the long arm (qh + is greater than, or equal to, twice the size of the short arm of chromosome 16 [16p]); very small or deficient heterochromatic region in the long arm (qh-); large Y (Yq + greater than size of chromosome 18), small Y (Yq- less than size of a G-group chromosome), and pericentric inversion of Y. Our prenatal study confirmed that the incidence of specific chromosomal variants is different in each population group. The most striking examples of this are the pericentric inversion of chromosome 9 and the different polymorphisms of the Y chromosome. The incidence of inv (9) is highest in the Black population (3.57%); slightly above average in Hispanics (2.42%); and relatively low in Whites (0.73%) and Asians (0.26%). The Y appears to be more variable in Asian (3.37%) and Hispanic (1.82%) than in White or Black groups. The 9qh+ is seen more frequently than 1qh+, or 16qh+. Inv (1), 9qh-, and 16qh- are rare. There were no cases of either 1qh- or inv (16).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
83.
Homozygote hypotransferrinaemic mice (hpx/hpx) have cytopathological features similar to those of human congenital atransferrinaemia, genetic haemochromatosis, and neonatal haemochromatosis. These conditions all have in common high levels of cytotoxic non-transferrin-bound serum iron. This study describes the ultrastructural features of iron overload in liver, pancreas, heart, and small intestine of 2- and 12-month-old hypotransferrinaemic mice. Electron microscopic studies of unstained sections showed early parenchymal cell siderosis, with accumulation of numerous ferritin particles and clusters in the cytosol, as well as ferritin and haemosiderin in lysosomes (siderosomes). In the 12-month-old animals, iron was also found in Kupffer cells and macrophages in other tissues. In addition, there were conspicuous iron-containing compounds in the bile canaliculi, and marked iron deposition in the pancreas and heart. Laser microprobe mass analysis (LAMMA) enabled localization and relative quantitation of iron deposition in subcellular compartments providing in situ documentation of iron accumulation in siderosomes and contributed in assessing total cytosolic iron in various cell types. Moreover, it demonstrated the importance and magnitude of the biliary route for iron excretion in these animals.  相似文献   
84.
We have studied a patient with clinically established Fanconi type anemia whose peripheral blood leukocyte culture and bone marrow showed a normal male karyotype, with no morphological alterations. The skin fibroblasts in cultures derived from his father, however, revealed a mosaic pattern, 47 , XY F+/46, XY. The findings of a trisomic cell line in a parent of a patient with Fanconi's anemia has been reported only once before.  相似文献   
85.
Neonatal sepsis is a major cause of death in newborns despite sophisticated neonatal intensive care. This retrospective study reviewed the clinical characteristics of cases of culture-proven sepsis in a neonatal intensive care unit from January 1992 to December 2001. Patients were divided into those with onset of sepsis in the first 7 days of life (early-onset group) and those with onset after the seventh day of life (late-onset group). A total of 270 cases with 325 episodes of sepsis and 353 isolated pathogens were identified and included in the study. The male-to-female ratio was 1.4. The majority of cases of sepsis occurred in low birth weight (75.9%) and premature babies (76.7%). Late onset occurred in 71.9% of cases. Patients with late onset had a lower mortality rate than those with early onset (11.3% vs 28.9%). Coagulase-negative staphylococci (20.1%) was the most common organism isolated, but infection with Pseudomonas aeruginosa was associated with the highest morality rate (55.0%). Late-onset sepsis was significantly more common in very low birth weight and premature infants. The most frequently encountered pathogens in the early-onset group were group B streptococci (GBS) and Escherichia coli, while in the late-onset group, the organisms were coagulase-negative staphylococci and Enterobacteriaceae, including E. coli, Klebsiella pneumoniae, and Acinetobacter baumannii. GBS infection resulted in the highest mortality when the onset of sepsis was within the first 24 hours of life.  相似文献   
86.
Previous work has established the importance of the 47-kilodalton (kDa) surface immunogen of Treponema pallidum subsp. pallidum (T. pallidum) in the immunopathogenesis of syphilis; the 47-kDa immunogen gene was cloned and expressed in Escherichia coli (M. V. Norgard, N. R. Chamberlain, M. A. Swancutt, and M. S. Goldberg, Infect. Immun. 54:500-506, 1986). To facilitate additional structural-functional analysis of this protein for immunopathogenesis studies, the recombinant DNA-derived molecule was examined with respect to its genetic expression and physicochemical properties. Subcloning of partial PstI digests of the original 47-kDa antigen-encoding DNA segment localized the 47-kDa antigen gene to a 1.3-kilobase (kb) T. pallidum DNA fragment. A 20- to 100-fold enhanced expression of the 47-kDa antigen was obtained when a 2.85-kb DNA insert containing the entire 1.3-kb structural gene was subcloned into a T7 RNA polymerase-dependent expression vector system. Under these conditions, several derivatives of the recombinant 47-kDa protein possessing different molecular masses were observed that were identical to those previously detected on Western blots of native T. pallidum antigens with monoclonal antibodies. Sarkosyl extraction of E. coli recombinant cell envelopes localized the 47-kDa protein to both the inner and outer membranes of E. coli. The absolute requirement of detergents (N-lauroylsarcosine, 3-[(3-chloramidopropyl)dimethylammonio]-1-propane sulfonate, N-octyl-beta-D-glucopyranoside, or Nonidet P-40) for solubilization of the antigen from E. coli cell envelopes and the observation that the recombinant protein partitioned into the detergent phase on Triton X-114 solubilization were consistent with the fact that it is a hydrophobic, integral membrane protein. Western blots of the 47-kDa antigen purified by immunoaffinity chromatography supported results of previous reports that the 47-kDa protein is specific to pathogenic treponemes.  相似文献   
87.
We report that the lymphokines (IFN-) and IL-10 are co-syntheslzedby previously described CD3+ TCRß+, minor antigen-specificsuppressor T cell clones. IFN- and IL-10 are known to (I) becharacteristically produced by different helper T cell types,Th1 and Th2 respectively, and (II) inhibit the function of thereciprocal subset of T cells: IFN- Inhibits the function ofTh2 and IL-10 that of Th1 cells. Although Th0 cells are alsoknown to synthesize cytoklnes of both the Th1- and Th2-typeT cells, the suppressor T cells described in this report aredifferent from Th0 cells in that they produce (I) neither IL-2nor IL-4 molecules and (II) stimulation via their CD3-TCR systemseems independent of both IL-2 and IL-4, the typical autocrinemolecules for T cell proliferation. The lymphokine profile ofthese suppressor T (TJ cell clones, as well as those of humanantigen-specific T. cells reported earlier, suggests that co-synthesisof some Th1-llke and some Th2-like cytoklnes may be a characteristicof antigen-specific T, cells as opposed to the type of reciprocalinhibition mediated through IFN- or IL-10, which is antigennon-specific.  相似文献   
88.
Monoclonal antibodies reactive with B and T lymphocytes, monocytes, and granulocytes were applied to B-5-, Bouin's-, or formalin-fixed paraffin-embedded sections. Most antigens were destroyed or masked by fixation or embedding procedures, or both. However, T200, an antigen present in all lymphoid and hematopoietic cells, and Leu M1, an antigen in granulocytes, were well preserved in formalin-fixed tissues. Leu 1 and BA-1, antigens present on T and B lymphocytes, respectively, were preserved in Bouin's-fixed specimens. With careful selection of fixatives, identification of some T and B lymphocytes and granulocytes by monoclonal antibodies in paraffin-embedded specimens is possible.  相似文献   
89.
We previously reported that T cells from aged mice were resistant to activation-induced cell death (AICD) in vitro. To determine whether the presence of AICD-resistant T cells is associated with defects in age-related peripheral clonal deletion in vivo, congenic male SCID mice were reconstituted with T cells from aged or young female D(b)/H-Y TCR (Tg71) transgenic mice. Compared with recipients of young cells, the recipients of T cells from aged mice exhibited a 3-fold increase in the percentage of autoreactive CD8(+) H-Y antigen-reactive T cells as defined by the clonotypic antibody, M33. There were significantly increased sera levels of interferon-gamma, a significantly decreased expression of FasL by M33(+)CD8(+) T cells, and significantly decreased apoptosis by DNA fragmentation staining of the spleen of mice reconstituted with T cells from aged mice compared to those from young mice. By day 21, the recipients of T cells from aged mice but not young mice, exhibited infiltration of CD3(+) cells into the non-lymphoid organs. These results indicate that there is defective peripheral deletion of the self-reactive T cells derived from aged female Tg71 mice, and that failure to delete these cells is associated with the defective T-cell clonal deletion in the recipient mice.  相似文献   
90.
To uncouple the defects of activation and apoptosis of T cells from aged mice, we used anti-CD3 plus IL-2 stimulation to induce an activation response and analyzed the subsequent activation-induced cell death (AICD) response of T cells from 16-month-old mice. The results herein demonstrate that T cells from 16-month-old mice could be activated by anti-CD3-induced activation signals but exhibited distinct phenotypic and functional features compared to young (2-month-old) mice. These include a decrease in AICD, a delayed entry into the cell cycle, and a decreased telomerase activity. The decreased AICD of T cells from 16-month-old mice is associated with a decreased expression of Fas and Fas ligand (FasL), decreased susceptibility to anti-Fas-induced apoptosis, and an increased expansion of a CD8(+) T-cell population. Prior to activation, these T cells exhibit a phenotype that is CD44(hi)CD62L(hi). After stimulation, these T cells produced high levels of the pro-inflammatory cytokine, IFN-gamma, and developed an increased population of IFN-gamma(+)IFN-gamma R(-) T cells. Our results suggest that there is a dysregulation in T-cell homeostasis in aged mice associated with a decrease in AICD of CD8(+) T cells.  相似文献   
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