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781.
In order to isolate promoters of mouse TGF-beta receptor genes, we used inverse PCR with highly overlapped primers corresponding to the 5' sequence of the receptor cDNAs. Nested primer sets only covered a 30- to 40-base region of the sequences. HinfI-digested and self-ligated mouse genomic DNA was used as a PCR template. Only one band for each receptor was seen after PCR. The amplified DNA fragments could direct luciferase production when the luciferase coding sequence was ligated after the fragments. The sequence of the fragment which correspond to the type II receptor showed partial homology with the promoter region of the human TGF-beta type II receptor. Thus, the inverse PCR with highly overlapped primers could be an easy way to isolate the promoter regions of many genes.  相似文献   
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783.
The authors report the case of a boy aged 4 years who had sudden abdominal pain and inability to walk on the day before admission to hospital and who developed abdominal distention and difficulty urinating. On admission, the abdominal skin reflexes, knee jerks, cremaster and anal reflexes were absent and power in the lower extremities was reduced. Spinal fluid examination showed a cell count of 383/mm3, with 95% neutrophils and 5% lymphocytes; spinal fluid protein of 44 mg/dl; and glucose 75 mg/dl. Serological studies did not reveal any significant antibodies for polio virus type 1, 2, 3, various ECHO viruses, Coxsackie types A4, A7, A9, B1 or B5. However, the titer of Coxsackie virus antibody type A10 was 128 in the acute phase and only 32 in the recovery phase 4 weeks later. Magnetic resonance scans were performed on the second day; the findings were normal in the brain, but interesting lesions were revealed in the thoracic cord with both T1-weighted images and T2-weighted images. Neurological symptoms improved asymmetrically.  相似文献   
784.
An immunohistochemistry method using formalin-fixed tissues, a direct immunofluorescence method using cryostat sections, an enzyme-linked immunosorbent assay (ELISA), and a PCR method were compared for diagnosis in a litter of weaned pigs that had been experimentally inoculated with wild-type porcine epidemic diarrhea virus (PEDV) and killed between 6 and 60 h after onset of diarrhea. The immunohistochemistry method proved to be as reliable as direct immunofluorescence for diagnosis of PEDV in tissues collected postmortem. The good reliability of ELISA for investigating clinical samples was confirmed, whereas the PCR method used was ineffective.  相似文献   
785.
Postmenopausal women with established vertebral osteoporosis were studied for 2 years to determine the terminal elimination half-life and the duration of response to treatment with intravenous alendronate (30 mg) given over 4 days. The urinary excretion of alendronate followed a multiexponential decline. Approximately 50% of the total dose was excreted over the first 5 days, and a further 17% was excreted in the succeeding 6 months. Thereafter, there was a much slower elimination phase with an estimated mean terminal half-life of greater than 10 years (n = 11). Urinary excretion of hydroxyproline and calcium decreased significantly from pretreatment values by day 3, reaching a nadir by 1 week (40% and 67% decrease, respectively). Thereafter, hydroxyproline remained suppressed for the following 2 years. In contrast, urinary calcium excretion returned gradually toward pretreatment values over the first year and during the second year was comparable to pretreatment values. Serum activity of alkaline phosphatase activity decreased over 3 months (23% reduction), increased gradually thereafter, and returned to pretreatment values at month 24. Bone mineral density measured at the spine increased by approximately 5% during the first year and remained significantly higher than pretreatment values at 2 years. We conclude that a short course of high doses of intravenous alendronate is associated with a prolonged skeletal retention of the agent. This open study also suggests that this regimen has a sustained effect on bone turnover persisting for at least 1 year.  相似文献   
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787.
Contents An algorithm suitable for computation of symmetrical components is presented in the paper. The algorithm is based on the Four-Sample Method and it extracts the rms values of the symmetrical components. The proposed algorithm is very simple and suitable for the application in the microprocessor-based metering and power system protection and monitoring.
Ein einfacher Algorithmus zur Erfassung symmetrischer Komponenten für Schutz und Überwachung
Übersicht In dem Beitrag wird ein geeigneter Algorithmus zur Berechnung symmetrischer Komponenten vorgestellt. Dieser beruht auf der Erfassung von vier Abtastwerten pro Grundperiode und liefert Effektivwerte der symmetrischen Komponenten. Der vorgeschlagene Algorithmus ist sehr einfach und anwendbar zur Meßwerterfassung mit Hilfe von Mikroprozessoren für den Schutz und die Überwachung von Energiesystemen.
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788.
789.
790.
A study is presented of the structure and function of the heart in the diastole in 39 patients during corinfar treatment of essential hypertension. It was established that effective corinfar monotherapy of patients with moderate essential hypertension was associated with arteriolo- and venodilating effect of the drug with prevalence of the preloading effect. Changes of the intracardiac hemodynamics resulted in changes of the left ventricular systole phase structure, namely, its transformation in the direction of myocardial hypodynamia.  相似文献   
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