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101.
102.
Annulo-aortic ectasia is an extremely rare complication of Gaucher's disease. We report successful surgery in a patient with Gaucher's disease complicated by annulo-aortic ectasia and aortic dissection. Cabrol's operation was accomplished without bleeding or sternal adaptation problems.  相似文献   
103.
In our previous study, we demonstrated that high-dose 60Co irradiation was able to prevent rejection of canine tracheal allografts. To determine the maximum possible length of these grafts, in the present study we attempted to transplant five-ring and ten-ring tracheal allografts in two groups of five dogs each. Either five or ten rings were excised from donor tracheas and irradiated with 100,000 cGy of 60Co. The irradiated tracheal grafts were transplanted to replace either five- or ten-ring sections of the mediastinal tracheas removed from the recipient dogs. The grafts were covered with omental pedicles and no immunosuppressants were used. Graft incorporation was achieved in four of the five dogs in the five-ring group, and three of these dogs survived for more than 700 days. However, four of the five animals in the ten-ring group died from tracheostenosis accompanied by ischemia within 3 weeks. These findings demonstrate the impossibility of performing ten-ring tracheal allotransplantation using irradiated grafts, even with omentopexy.  相似文献   
104.
105.
Background Stressful psychological stimuli produce an increase in renal sympathetic nerve activity (RSNA) and a decrease in renal blood flow. Very few direct analyses of the relationship between RSNA and renal blood flow during the application of psychological stimuli have been conducted by recording these 2 measurements simultaneously in the same individual animals. Methods We simultaneously measured RSNA and renal blood flow as a Doppler shift in conscious, unrestrained, spontaneously hypertensive rats. The rats were stressed by directing a continuous air jet at their faces for 20 seconds. Results Air-jet stimulus increased RSNA 81%±15% (mean±standard error of the mean, n=10), mean arterial pressure (21±3 mm Hg), and renal vascular resistance (37%±6%), and decreased renal blood flow (−15%±2%). The percentage change in RSNA correlated positively with the change in mean arterial pressure (r=0.934,P<0.001) and percentage change in renal vascular resistance (r=0.912), and negatively with the percentage change in renal blood flow (r=−0.804). The denervation of renal nerves prevented renal blood flow from decreasing in response to air-jet stress. Conclusions A reduction in renal blood flow in response to short-term air-jet stress is elicited mainly by neural mechanisms in spontaneously hypertensive rats. Enhancement of RSNA by air-jet stimulus exerts a potent constricting effect on the renal vascular bed, resulting in a reduction in renal blood flow.  相似文献   
106.
The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone, one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant therapy in breast cancer patients, especially in premenopausal patients using tamoxifen.  相似文献   
107.
108.
Optimal initial palliation and a subsequent staged approach is mandatory for high-risk Fontan candidates. We describe the case of mitral atresia with severe tricuspid regurgitation and pulmonary hypertension successfully managed by repeated palliation from the neonatal period and 2-stage Fontan surgery. A 1-month-old boy diagnosed with mitral atresia and double-outlet right ventricle underwent pulmonary artery banding at 1 month of age, followed by repeated pulmonary artery banding accompanied by tricuspid annuloplasty and atrial septal defect enlargement at 6 months. Because of the presence of pulmonary artery distortion, right ventricular dysfunction, and borderline pulmonary vascular resistance, a hemi-Fontan procedure was conducted with extended pulmonary artery plasty when the boy was 3 years and 8 months old. Cardiac catheterization done 3 months after showed improvement in risk factors, and the final Fontan operation (total cavopulmonary connection) was successfully done in conjunction with repeated tricuspid annuloplasty when the boy was 4 years and 5 months old. The patient remains in excellent clinical condition at the last follow-up 5 years after the final Fontan procedure with sinus rhythm and good ventricular function.  相似文献   
109.
Recent neurophysiological studies have disclosed that the nucleus of the optic tract (NOT) in the pretectum is the first relay station responsible for horizontal optokinetic nystagmus (OKN) both in non-foveate and foveate animals. However, what parts of the retina and what kinds of retinal ganglion cells project their fibers into the NOT have been controversial. In the present study, horseradish peroxidase conjugated with wheatgerm agglutinin (WGA-HRP) was injected into the NOT of rats. The retina and injection sites were processed for the histochemical demonstration of WGA-HRP in order to investigate the distribution of the retinal ganglion cells projecting into the NOT. The present study indicated that visual signals responsible for OKN are mainly conducted from the contralateral retinal ganglion cells, and only from the ventral area of the ipsilateral retina. The retinal ganglion cells projecting into the NOT ipsilateral to the injection site were larger than those on the contralateral side. Large retinal ganglion cells existed on the peripheral areas including ipsilateral ventral area. The density of the ventral ganglion cells of the retina contralateral to the injection site was lower than that in other areas of retina, and the density of the ventral ganglion cells ipsilateral to the injection site tented to be greater than that on the contralateral side. Since the ventral area of retina corresponded to the upper visual field in front of the nose, it may receive visual signal of OKN and fire OKN. In conclusion, visual signals responsible for OKN are conducted through the retinal ganglion cells mainly contralaterally, and only from the ventral area of the retina ipsilateral to the injection site.  相似文献   
110.
Several subfamilies of the salmonid Hpa I short interspersed element (SINE) family were isolated from salmonid genomes and were sequenced. For each genomic locus that represented the subfamily, amplification by PCR of the orthologous loci in the 12 fish allowed us to determine the order of branching of the Pacific salmonid species. The deduced phylogeny suggests three evolutionary lines, namely, a line of chum salmon, pink salmon, and kokanee; a line of coho salmon and chinook salmon; and a line of steelhead trout. Our data also support a change in the phylogenetic assignment of steelhead trout from Salmo to Oncorhynchus. We present here an extensive phylogenetic tree constructed from an analysis of differential insertion of SINEs, and we propose that SINE insertion analysis is one of the best available methods for clarifying the order of divergence of closely related species.  相似文献   
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