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1.
A series of 5-hydroxy and 5-benzyloxy analogs of the antiarrhythmic and multidrug resistance (MDR) modulating drug propafenone was synthesized and the MDR-modulating activity of the compounds was evaluated using a daunomycin efflux assay system. The key step of the synthesis is the selective reduction of the double bond in 1 without cleavage of the benzyl group thus leading to the phenol 3 . Alkylation with epichlorohydrine followed by nucleophilic epoxide ring opening gave the benzylated target compounds 5a–d . Subsequent cleavage of the benzyl group gave the 5-hydroxy analogs 6a–d . Structure activity relationship studies showed, that the 5-hydroxy derivates 6a–d fit the log P/log potency correlation line previously established for a series of propafenone analogs. In contrast, all four 5-benzyloxy analogs 5a–d showed almost identical EC50 values, independent of their log P value.  相似文献   
2.
Hirschsprung's disease: associated abnormalities and demography.   总被引:3,自引:0,他引:3  
We here examine the demographic parameters of patients with Hirschsprung's disease. The study population includes all patients with histologically confirmed disease treated at the Children's Hospital Medical Center of Boston over the 25-year period extending from 1961 through the first quarter of 1986. There were 179 cases. Overall, children with Hirschsprung's disease were found less likely to be first born (P less than .01). This relationship was seen to persist irrespective of maternal age, maternal race, or type of disease. The implications of this finding are discussed. Overall, 22% of these children had one or more associated abnormalities involving the neurological, cardiovascular, urological, and gastrointestinal systems. Many of the disorders appeared to be related to neurocrestopathies. Frequent associations included Down's syndrome, defects in cardiac septation, tetralogy of Fallot, and Dandy-Walker syndrome. These conditions occurred more frequently than would have been predicted through chance alone. This study found no association between an increased maternal age and the occurrence of Hirschsprung's disease. This study also found that approximately 7% of the affected children had been born prematurely.  相似文献   
3.
In a prospective, randomized study of insemination with donor semen, intracervical insemination by straw was compared with insemination using a cervical cap with an intracervical reservoir. A total of 91 patients completed 486 treatment cycles. There were no significant differences in age, parity, indication for insemination by donor, or method of cycle monitoring between women who became pregnant and those who did not conceive with either insemination method. In 236 standard intracervical insemination cycles, 14 patients became pregnant (5.9% per cycle), whereas 38 patients conceived in 250 cervical cap cycles (15.2% per cycle). Both the crude pregnancy rates and the cumulative pregnancy rates calculated by the Kaplan-Meier life-table method were significantly different (chi(2)-test, P < 0.001, and log-rank test, P < 0.005 respectively). Pregnancy rates in artificial insemination with cryopreserved donor semen may be improved by the use of a cervical cap when compared to cervical insemination by straw. The use of the cervical cap may prolong the exposure of the spermatozoa to the cervical mucus and prevent the backflow of semen into the vagina.   相似文献   
4.
Femoral stress fractures following revision total hip arthroplasty developed about a cortical window in two patients. These cases differ from previously reported fractures in that there was no significant trauma, the pain was gradual in onset, and there was no displacement at the fracture site. Tomograms and radionuclide bone scans were necessary to reveal the fracture. One femur healed with hip spica immobilization, while the other required bone grafting. Femoral stress fractures should be considered in the differential diagnosis of patients with thigh pain after revision total hip arthroplasty, particularly if a cortical window had been necessary.  相似文献   
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The ocular tropism of adenovirus type 37 (Ad37) does not correlate with the wide distribution of the 46-kDa coxsackievirus and adenovirus receptor (CAR), the major receptor for most adenovirus serotypes. We previously found that Ad37 infects and binds well to conjunctival cells (Chang C), but poorly to lung epithelial (A549) cells that express CAR and hypothesized that this serotype uses a distinct receptor that is selectively expressed on conjunctival cells. To test this, we produced particles of a fiber-deleted Ad5 vector containing the Ad37 fiber protein. The "pseudotyped" vector infected Chang C cells better than A549 cells using a CAR-independent pathway. Ad37 binding was calcium-dependent and was abolished by protease digestion of cell surface proteins. Using a virus overlay protein blot assay (VOPBA), we detected calcium-dependent Ad37 binding to 50- and 60-kDa membrane proteins on permissive Chang C cells. In contrast, calcium-dependent binding was detected with only the 60-kDa protein on nonpermissive A549 cells. Ad19p, a closely related serotype that failed to bind to conjunctival cells, recognized the 60-kDa, but not the 50-kDa, protein. Ad37 has been reported to use sialic acid instead of CAR as a cell receptor on A549 cells. Pretreatment of Chang C cells with neuraminidase abolished Ad37 binding to only the 60-kDa protein, suggesting that sialic acid mediates Ad37 binding to the 60-kDa protein. The pseudotyped Ad37 vector was also able to infect neuraminidase-treated Chang C cells. Thus, subgroup D adenoviral binding to the 50-kDa protein is calcium-dependent and cell type- and serotype-specific, whereas binding to the 60-kDa protein is not necessary for infection of conjunctival cells. Together, these data suggest that the 50-kDa protein is the major receptor for Ad37 on conjunctival cells.  相似文献   
9.
An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.   相似文献   
10.
Digital data from 3‐D treatment planning computers is generally used for patient planning and then never considered again. However, such data contains enormous quantities of information regarding patient geometries, tissue outlining, treatment approaches and dose distributions. Were such data accessible from planning systems from multiple manufacturers, there would be substantial opportunities for undertaking quality assurance of radiotherapy clinical trials, prospective assessment of trial outcomes and basic treatment planning research and development. The technicalities of data exchange between planning systems are outlined, and previous attempts at producing systems capable of viewing and/or manipulating imaging and radiotherapy digital data reviewed. Development of a software system for enhancing the quality of Australasian clinical trials is proposed.  相似文献   
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