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21.
This review comprises 36 patients who were treated for Asherman's syndrome from 1968 to 1974 at the Sloane Hospital for Women. Of the 18 patients who later conceived only 6 had uncomplicated term deliveries. Four had premature deliveries resulting in neonatal death. Three had placenta accreta and postpartum hemorrhage, necessitating a cesarean hysterectomy in 1. Two patients required cesarean section for complications due to the syndrome, 2 had spontaneous abortion, and 1 had a cervical pregnancy requiring total hysterectomy. Only 10 babies survived. The incidence and severity of complications in conceptions following treatment for Asherman's syndrome is high, and the obstetrician must be prepared to manage them.  相似文献   
22.
Blood-engorged Culex tarsalis (4,209) collected during 1960 to 1965 in Kern County, California and previously shown to have fed on passeriform birds by the precipitin test were further tested by the more sensitive passive hemagglutination inhibition test (PHI). It was shown that these mosquitoes fed principally on House Finches and House Sparrows, the most common passeriform birds found in the collection areas. These data demonstrate the usefulness of the PHI test for the identification of arthropod blood meals from closely related species.  相似文献   
23.
    
Calmodulin-dependent protein kinase II (Cam kinase II) is known to desensitise epidermal growth factor receptor (HER-1) tyrosine kinase activity by a process involving phosphorylation at serines 1046/47 in the cytoplasmic tail. We have developed an experimental system to investigate phosphorylation of the related HER-2/c-erbB2 proto-oncogene utilising purified Cam kinase II and recombinant glutathione-S-transferase (GST) fusion proteins. The cDNA for rat Cam kinase II-alpha was transfected into human embryonic kidney (HEK) 293 fibroblasts and the expressed protein purified to homogeneity by calmodulin-agarose affinity chromatography. A GST fusion protein comprising residues 1126-1255 of HER-2 was phosphorylated by purified Cam kinase II, in contrast to a GST protein comprising residues 1005-1125. Phosphoamino-acid analysis and site-directed mutagenesis indicated that HER-2 was phosphorylated on a single site at threonine-1172 which resides within a consensus Cam kinase II phosphorylation site (RAKT). HER-2 (threonine-1172-alanine), in the form of a ligand-inducible chimaera HER-1/2, was co-transfected into HEK-293 fibroblasts with a constitutively active form of Cam kinase II, followed by in vivo labelling of these cells with 32 P-orthophosphate. Immunoprecipitation of ligand-activated receptors followed by two-dimensional phosphopeptide mapping indicated that threonine-1172 in HER-2 is a newly identified in vivo site which can be hyper-phosphorylated by constitutively active Cam kinase II. In addition, when over-expressed in HEK-293 fibroblasts, HER-1/2 (threonine-1172-alanine) showed a defect in desensitisation and underwent a more sustained EGF-induced receptor autophosphorylation compared to wild-type HER-1/2.  相似文献   
24.
    
Airway control and protection, in any operation, is the first priority. The presence of a T-Y stent in the proximal airway can complicate this fundamental principle. Here we describe an effective and safe technique for positive-pressure single-lung ventilation via a T-Y stent for a lung lobectomy.  相似文献   
25.
    
OBJECTIVE: To determine the efficacy of genetic testing of individuals presenting with features possibly indicative of von Hippel-Lindau (VHL) disease, regardless of other relevant family and clinical details. SETTING AND PARTICIPANTS: Between September 1994 and December 1997, 16 unrelated individuals were referred to Genetic Services of Western Australia by local clinicians and by similar genetic services in other States, for VHL gene mutation analysis because of clinical manifestations suggestive of the diagnosis. METHODS: The subjects were investigated by screening for mutations in the polymerase chain reaction products of the three VHL gene exons using single-stranded conformational polymorphism analysis (SSCP). If no mutations were detected the exons were sequenced, and if no variations were found DNA was examined by Southern analysis for germinal rearrangements. RESULTS: Mutations in the VHL gene were detected in eight of 16 individuals (50%), including 3 individuals with no family history suggestive of VHL disease. Five mutations were detected by SSCP, two by gene sequencing and one by Southern analysis. Each mutation occurred only in a single family and three had not been previously reported. CONCLUSION: Genetic screening of individuals presenting with clinical features suggestive of VHL facilitates confirmation of the diagnosis, accurate genetic counselling and surveillance of at-risk family members. The necessity for costly and time-consuming screening programs can be reduced and screening directed at those carrying the mutation. Our low stringency criteria are justified for screening for VHL mutations.  相似文献   
26.
    
ETR1 represents a prototypical ethylene receptor. Homologues of ETR1 have been identified in Arabidopsis as well as in other plant species, indicating that ethylene perception involves a family of receptors and that the mechanism of ethylene perception is conserved in plants. The amino-terminal half of ETR1 contains a hydrophobic domain responsible for ethylene binding and membrane localization. The carboxyl-terminal half of the polypeptide contains domains with homology to histidine kinases and response regulators, signaling motifs originally identified in bacteria. The putative histidine kinase domain of ETR1 was expressed in yeast as a fusion protein with glutathione S-transferase and affinity purified. Autophosphorylation of the purified fusion protein was observed on incubation with radiolabeled ATP. The incorporated phosphate was resistant to treatment with 3 M NaOH, but was sensitive to 1 M HCl, consistent with phosphorylation of histidine. Autophosphorylation was abolished by mutations that eliminated either the presumptive site of phosphorylation (His-353) or putative catalytic residues within the kinase domain. Truncations were used to delineate the region required for histidine kinase activity. An examination of cation requirements indicated that ETR1 requires Mn2+ for autophosphorylation. These results demonstrate that higher plants contain proteins with histidine kinase activity. Furthermore, these results indicate that aspects of ethylene signaling may be regulated by changes in histidine kinase activity of the receptor.  相似文献   
27.
    
The North Central Cancer Treatment Group designed a phase II trial to assess the efficacy and toxicity of topotecan in patients with unresectable malignant pleural mesothelioma. Twenty-two previously untreated patients with unresectable pleural mesothelioma and good performance status (Eastern Cooperative Oncology Group performance status 0, 1, or 2) were enrolled on this trial from October 1993 through July 1994. Nineteen men and three women, median age 66 years (range, 44-78 years), were treated with topotecan 1.5 mg/m2 intravenously over 30 minutes daily for 5 days at 3-week intervals until toxicity, progression of disease, or a patient decided to discontinue treatment. There were seven patients with measurable disease and 15 with evaluable disease; all were assessable for response and toxicity. A total of 113 cycles of treatment were given, for a median of three cycles (range, 1-26 cycles). Myelosuppression was the most frequent toxicity. Eighteen of 21 patients (86%) experienced grade 3 or 4 neutropenia during the initial treatment cycle. The median neutrophil nadir was 0.5 x 10(3)/microl (range, 0.1-1.6 x 10(3)/microl), and the median platelet nadir was 127 x 10(3)/microl (range, 18-460 x 10(3)/microl). Other toxicities more than grade 2 included malaise (two patients), and anorexia, infection, fever, pulmonary, and cardiac in one patient each. There were no objective responses, and 18 patients had stable disease for a median of 74 days. The median survival for all patients was 230 days, with 23% alive at 1 year. Topotecan as administered in this trial is reasonably well tolerated; however, the response rate was insufficient to warrant additional study in pleural mesothelioma.  相似文献   
28.
    
OBJECTIVE: This study examines our continuing experience in performing vaginal hysterectomies and laparoscopy-assisted vaginal hysterectomies with an outpatient protocol. The purpose was to review factors associated with discharge and hospitalization. STUDY DESIGN: Surgical records from all women entering our previously reported outpatient hysterectomy protocol were reviewed. Demographics, surgical indications, intraoperative data, and postoperative data were studied, and their associations with patient discharge and hospitalization were determined. Specific attention was directed to complications. RESULTS: The study group consisted of 133 women. Twelve women (9.0%) were not discharged from the hospital and 5 (3.8%) required readmission. Surgical indications, the type of hysterectomy, and the requirement for pain medication revealed no association with hospitalization. The occurrence of an intraoperative complication (p < 0.000), the need for transfusion (p = 0.043), and postoperative antiemetics (p = 0.013) were statistically associated with hospitalization. In addition, low hematocrit values and elevated temperatures on the first and second postoperative days were associated with hospitalization. CONCLUSION: Long-term experience with outpatient hysterectomy reveals a hospitalization rate of 12.8%. Complications, blood loss, elevated temperatures, and postoperative nausea are the major determinants of patient discharge and hospitalization. Readmission rates continue to remain low.  相似文献   
29.
30.
    
Three variable microsatellite loci have been isolated from the American lobster, Homarus americanus. In a population sample from the Gulf of Maine, the effective numbers of alleles (Ne) for the two most variable loci were 16.33 and 13.19, respectively. Reduced variability at all three loci was seen in the European lobster, H. gammarus, for which the maximum Ne was 4.00. The reduction in variability in H. gammarus is consistent with a bottleneck event. Inheritance analysis using H. americanus demonstrated segregation of codominant alleles and the absence of linkage. Null alleles were observed at two loci in inheritance studies. This study demonstrates that microsatellite loci should be useful in studying the population structure of clawed lobsters.  相似文献   
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