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991.
Ultrasound-guided embryo transfer improves pregnancy rates and increases the frequency of easy transfers 总被引:7,自引:0,他引:7
Matorras R Urquijo E Mendoza R Corcóstegui B Expósito A Rodríguez-Escudero FJ 《Human reproduction (Oxford, England)》2002,17(7):1762-1766
BACKGROUND: Recent reports have suggested that ultrasound (US) guidance during embryo transfer might improve pregnancy rates. METHODS: A prospective randomized (computer-generated random table) trial was performed to compare embryo transfer under abdominal US guidance (n = 255 women) with clinical touch embryo transfer (n = 260). RESULTS: The clinical pregnancy rate was 26.3% (67/255) in the US-guided transfer group compared with 18.1% (47/260) in the clinical touch transfer group (P < 0.05). The implantation rate was 11.1% (100/903) in the US group compared with 7.5% (66/884) in the clinical touch group (P < 0.05). US-guided transfer was associated with a decrease in the difficulty of the transfers: 97% of transfers were easy in the US-guided group compared with 81% in the clinical touch group (P < 0.05). CONCLUSIONS: US-guided embryo transfer increased pregnancy and implantation rates in IVF cycles, as well as the frequency of easy transfers. It is suggested that the decrease in cervical and uterine trauma can play a role in the increase in pregnancy rates associated with US-guided transfer. It is recommended that embryo transfer should be performed under US guidance. 相似文献
992.
993.
Summary. BCH4 cells, persistently infected with Human Respiratory Syncytial Virus (HRSV), were obtained by Fernie et al. [12] after
infection of a BALB/c mouse embryo cell line with the Long strain of HRSV. To understand the basis of HRSV persistence, the
expression of HRSV RNAs and proteins was evaluated in BCH4 cells and infected parental BALB/c and fully permissive HEp-2 cells.
Production of viral mRNAs was severely impaired in BCH4 cells. In addition, the expression level of the surface glycoproteins
F and G was markedly reduced relative to internal viral proteins. However, virus recovered from BCH4 cells could lytically
infect HEp-2 cells and expressed normal levels of surface glycoproteins. No evidence of defective genomes or interfering particles
was found in BCH4 cells. Taken together, these data indicate that reduction of both viral mRNA accumulation and surface glycoprotein
biosynthesis are at the basis of HRSV persistence in BCH4 cells.
Accepted November 3, 2000 相似文献
994.
Arroyo JC Gabilondo F Llorente L Meraz-Ríos MA Sánchez-Torres C 《Journal of clinical immunology》2004,24(1):86-96
Monocyte-derived dendritic cells (mDC) are increasingly used as cancer vaccines. However, human monocytes are a heterogeneous cell population. We showed previously that DC derived from a monocyte subset expressing CD16 (16+mDC) stimulated allogeneic naïve T lymphocytes to secrete higher levels of IL-4 than DC derived from regular CD14highCD16? monocytes (16?mDC). Th1-type responses have been associated with effective antitumor responses, thus the use of mDC containing 16+mDC as cancer vaccines might be disadvantageous. Here, we evaluate the primary and memory immune response elicited in vitro by 16+mDC and 16?mDC in five patients with metastatic renal cell carcinoma vaccinated with autologous mDC pulsed with tumor lysates (TuLy) and keyhole limpet hemocyanin (KLH). After therapy, three of the five patients had stable disease. Surprisingly, patients with longer survival showed the highest amount of peripheral blood CD16+ monocytes. Analysis of KLH-specific antibodies revealed high titers of IgG2 in patients with longer survival. CD4+ T lymphocyte proliferation against KLH and TuLy increased after treatment, and some patients showed an augmented rate of CD4+ T lymphocyte proliferation against KLH (3/5) and TuLy (2/3) when 16+mDC were used as antigen presenting cells (APC). Before treatment, the IFN-γ/IL-4 ratio against TuLy and KLH was higher when using 16?mDC as APC, but after vaccination four of five patients had an increased ratio for TuLy with 16+mDC. These results suggest that the immune response elicited by 16?mDC and 16+mDC is modified when memory or naïve T cells are stimulated, and 16+mDC could favor a stronger and more beneficial antitumoral Th1 memory response in vivo. 相似文献
995.
Marques da Silva SH Queiroz-Telles F Colombo AL Blotta MH Lopes JD Pires De Camargo Z 《Journal of clinical microbiology》2004,42(6):2419-2424
Paracoccidioidomycosis (PCM) is a systemic fungal disease that is particularly important among individuals living and working in rural areas of endemicity in Latin America. Detection of anti-Paracoccidioides brasiliensis antibodies is of limited value due to false-negative results. Detection of P. brasiliensis-gp43 circulating antigen is a practical approach for a specific diagnosis of the disease. In a previous study we described an inhibition enzyme-linked immunosorbent assay able to detect the 43-kDa P. brasiliensis antigen in sera of 100% of patients with the acute form of PCM and in 95.31 and 100% of patients with the chronic multifocal and unifocal forms of PCM. To investigate its potential application for the follow-up of PCM patients during treatment, antigen levels were monitored at regular intervals for up 8 to 12 months in serum samples from 23 patients. The results showed that treatment with itraconazole resulted in decreasing levels of circulating gp43 that were correlated with the reduction of anti-gp43 antibodies. It was also observed that by the end of 12 months of treatment gp43 levels were <5 microg/ml in all patients. 相似文献
996.
Sousa MM Ferrão J Fernandes R Guimarães A Geraldes JB Perdigoto R Tomé L Mota O Negrão L Furtado AL Saraiva MJ 《Laboratory investigation; a journal of technical methods and pathology》2004,84(7):865-873
Familial amyloid polyneuropathy (FAP) is characterized by deposition of mutated transthyretin (TTR) in the peripheral nervous system. Prior to amyloid fibrils, nonfibrillar TTR aggregates are deposited inducing oxidative stress with increased nitration (3-NT). As the major source of TTR is the liver, liver transplantation (LT) is used to halt FAP. Given the shortage of liver donors, domino LT (DLT) using FAP livers is performed. The correlation between TTR deposition in the skin and nerve was tested in biopsies from normal individuals, asymptomatic carriers (FAP 0) and FAP patients; in FAP 0, nonfibrillar TTR was observed both in the skin and nerve in the same individuals; in patients, amyloid was detected in both tissues. The occurrence of amyloidosis in recipients of FAP livers was evaluated 1-7 years after DLT: TTR deposition occurred in the skin 3 years after transplantation either as amyloid or aggregates; in one of the recipients, fibrillar TTR was present in the epineurium 6 years after DLT. Deposits were scarce and 3-NT immunostaining was irrelevant. Nerve biopsies from DLT recipients had no FAP-related neuropathy. Our findings suggest that TTR amyloid formation occurs faster than predicted and that TTR of liver origin can cross the blood-nerve barrier. Recipients of FAP livers should be under surveillance for TTR deposition and tissue damage. 相似文献
997.
López-Giral S Quintana NE Cabrerizo M Alfonso-Pérez M Sala-Valdés M De Soria VG Fernández-Rañada JM Fernández-Ruiz E Muñoz C 《Journal of leukocyte biology》2004,76(2):462-471
B cell neoplasms present heterogeneous patterns of lymphoid organ involvement, which may be a result of the differential expression of chemokine receptors. We found that chemokine receptor (CCR)7, CXC chemokine receptor (CXCR)4, or CXCR5, the main chemokine receptors that mediate B cell entry into secondary lymphoid tissues and their homing to T cell and B cell zones therein, were highly expressed in B malignancies with widespread involvement of lymph nodes. Conversely, those pathologies with little or no nodular dissemination showed no expression to very low levels of CCR7 and CXCR5 and low to moderate levels of CXCR4. These findings provide evidence for the role of CCR7, CXCR4, and CXCR5 in determining the pattern of lymphoid organ involvement of B tumors. Functional studies were performed on B malignancies expressing different levels of CCR7, CXCR5, and CXCR4. Multiple myeloma (MM) cells did not express CCR7 nor CXCR5 and did not migrate in response to their ligands; a moderate expression of CXCR4 on MM cells was accompanied by a migratory response to its ligand, CXCL12. By contrast, cells from B cell chronic lymphocytic leukemia (B-CLL) expressed the highest levels of these chemokine receptors and efficiently migrated in response to all ligands of CCR7, CXCR4, and CXCR5. In addition, the migration index of B-CLL cells in response to both of the CCR7 ligands correlated with the presence of clinical lymphadenopathy, thus indicating that the high expression of functional chemokine receptors justifies the widespread character of B-CLL, representing a clinical target for the control of tumor cell dissemination. 相似文献
998.
Tadokoro CE Vallochi AL Rios LS Martins GA Schlesinger D Mosca T Kuchroo VK Rizzo LV Abrahamsohn IA 《Journal of autoimmunity》2004,23(2):103-115
Trypanosoma cruzi is an intracellular parasite that induces a strong Th1-type response and immunosuppression during the acute phase of infection. To study how the infection with T. cruzi would modulate the development of an autoimmune disease, we immunized C57BL/6 mice and IL-10 or iNOS knock-out mice of the same background with the encephalitogenic MOG 35-55 peptide and infected them with T. cruzi. Our results demonstrate that infection with T. cruzi completely prevents EAE development and furthermore induces complete and lasting remission in mice that were infected with this parasite after they had developed clinical EAE. Nitric oxide and IL-10 participate in triggering the mechanisms associated with EAE suppression by the infection. Decreased lymphoproliferation and increased frequencies of Annexin-positive cells and of T cells bearing CD95, CD95L or CTLA-4 were observed in the spleen from immunized/infected mice, as well as lower IL-2 and increased TGF-beta production in comparison with only immunized mice. Our results indicate that several effector and regulatory mechanisms of the immune response that arise during the acute phase of T. cruzi infection lastingly affect the expansion and/or effector functions of encephalitogenic cells, preventing the onset or inducing complete remission of EAE. 相似文献
999.
The sciatic nerve was crushed in the right hindlimb in newborn (3-8 h old) rats. Two to four months later, electromyographic activity was recorded from both the control and reinnervated ankle extensor muscles soleus or lateral gastrocnemius and from the ankle flexor muscle tibialis anterior. Tonic postural activity was present in the extensor muscles on both sides during quiet stance. The control flexor muscles were usually silent in this situation, but the reinnervated flexors exhibited abnormal sustained activity. During locomotion, the control extensors were activated during the stance phase and their mean burst made up 61.5% of the step cycle. The control tibialis anterior muscle fired only during the swing phase, with the burst lasting 18.1% of the step cycle. In the reinnervated extensor muscles, the mean burst duration was decreased (46% of the cycle) but the basic locomotor pattern was not impaired. The reinnervated tibialis muscle, however, was activated abnormally, with one appropriate flexor burst during the swing phase and an "extensor-like" burst during the stance phase of the step. Reflex responses to stretch were weak or absent on the operated side. Histological examination showed that the reinnervated soleus and tibialis muscles were almost devoid of muscle spindles. The motor unit mean firing rates in the reinnervated soleus (22 imp/s) and lateral gastrocnemius (45 imp/s) matched those of the control muscles (25 and 42 imp/s, respectively). In contrast to the phasic, high-frequency firing (52-80 imp/s) in the control tibialis, the reinnervated tibialis motor units fired at significantly lower rates (22-56 imp/s).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
1000.
Cenarro A Jensen HK Casao E Civeira F González-Bonillo J Rodríguez-Rey JC Gregersen N Pocoví M 《Human mutation》1998,11(5):413
We used the single strand conformation polymorphism (SSCP) method to investigate 13 apparently unrelated Spanish patients with familial hypercholesterolemia (FH) for mutations in the promoter region and the 18 exons and their flanking intron sequences of the low density lipoprotein (LDL) receptor gene. We found 16 aberrant SSCP patterns, and the underlying mutations were characterized by DNA sequencing. Five novel missense mutations, Q71E, C74G, C95R, C281Y and D679E, and one nonsense mutation, Q133X, were identified. We also found six missense mutations, S156L, D200Y, D200G, E256K, T413K and C646Y, and one stop codon mutation, W(-18)X, that were previously described in patients from other populations. A new frameshift mutation, 2085del19, was found in one patient. We also identified three splicing mutations; two of them are novel mutations, 1706-10G->A and 2390-1G->A, and the other one has been reported recently, 313+1G->C. Four patients were found to carry two different mutations in the same allele: Q71E and 313+1G->C; C95R and D679E; W(-18)X and E256K, and C281Y and 1706-10G->A. Our results demonstrate that there is a broad spectrum of mutations in the LDL receptor gene in the Spanish population. 相似文献