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A synthetic DNA based on the known amino acid sequence of the brain/gut peptide cholecystokinin (CCK) was synthesized. This DNA contained deoxyinosines at ambiguous codon positions and was used as a probe to isolate the CCK gene directly from a human genomic library. Nucleotide sequence analysis of the isolated gene revealed that human preprocholecystokinin consists of 115 amino acid residues, with 11 amino acids in common with the human gastrin precursor, another member of the gastrin-CCK family, and that the coding region is separated by a single, long intron. CCK appears to be encoded by a single-copy gene in the haploid human genome, as revealed by genomic Southern hybridization analysis, suggesting that the same gene is expressed both in gut and brain.  相似文献   
85.
Influence of luminal Ca2+ on the integrity of normal mucosa and recovery of damaged mucosa in anesthetized rat stomachs was studied using a perfusion system. Changes in the mucosal integrity were monitored by measuring transmucosal potential difference (PD) and luminal pH. EDTA, a Ca2+ chelator, dose-dependently reduced PD and increased luminal pH. Five mM Ca2+ (CaCl2) alone produced no changes in either PD and luminal pH, but the PD which was reduced by 250 mM EDTA was significantly recovered. Ethanol or NaCl concentration-dependently reduced PD, but gradually reverted to baseline levels. While 5 mM Ca2+ or 5 mM EDTA did not influence the reduction in PD with 50% ethanol or 1 M NaCl, these agents either enhanced or delayed the recovery processes in reduced PD, respectively. Five mM Ca2+ enhanced the recovery of PD which was reduced by 50% ethanol plus 5 mM EDTA. Gastric damage induced by 50% ethanol plus 5 mM EDTA was much more severe than that induced by 50% ethanol alone or 50% ethanol plus 5 mM Ca2+. Both 50% ethanol and 1 M NaCl significantly increased Ca2+ contents in the gastric lumen. Luminal Ca2+ appears to play an important role in maintaining mucosal integrity, under normal physiological conditions, and in accelerating the recovery process of damaged mucosa in rat stomachs.  相似文献   
86.
Summary The gene encoding the specific glycosyltransferases which catalyze the conversion of the H antigen to A or B antigens shows a slight but distinct variation in its allelic nucleotide sequence and can be divided into 6 genotypes when digested with specific restriction enzymes. We extracted DNA from formalin-fixed, paraffin-embedded tissues using SDS/proteinase K treatment followed by phenol/chloroform extraction. The sequence of nucleotides for the A, B and O genes was amplified by the polymerase chain reaction (PCR). DNA fragments of 128 by and 200 by could be amplified in the second round of PCR, using an aliquot of the first round PCR product as template. Degraded DNA from paraffin blocks stored for up to 10.7 years could be successfully typed. The ABO genotype was deduced from the digestion patterns with an appropriate combination of restriction enzymes and was compatible with the phenotype obtained from the blood sample.  相似文献   
87.
1 ), forced vital capacity, static compliance, and maximal oxygen uptake. The functional residual capacity as measured by the gas dilution method (FRCgas), was unchanged; however, it was found to be decreased significantly when measured by body plethysmograph (FRCbox). Positive correlations existed between the reduction in FRCbox and the increase in FEV1 (r = 0.586, P = 0.0042) and maximal oxygen uptake (r = 0.550, P = 0.018). Pulmonary ventilation and exercise ability in patients with pulmonary emphysema were improved in a volume-dependent manner by thoracoscopic lung volume reduction. These findings indicate that patients with a preoperative trapped gas volume level exceeding 1 l would be ideal candidates for thoracoscopic lung volume reduction. (Received for publication on Mar. 4, 1998; accepted on Jan. 7, 1999)  相似文献   
88.
BACKGROUND: A very rare case of retroperitoneal bleeding due to spontaneous rupture of a large adrenal myelolipoma in a 62-year-old woman is reported. METHODS/RESULTS: She consulted the emergency room of the Nagano Red Cross Hospital with a complaint of sudden left flank pain. A computerized tomography (CT) scan revealed a tumor with areas of fat density and hematoma in the left retroperitoneal space. After her general condition improved, an operation was performed. The tumor strongly adhered to the left kidney and a left nephrectomy with the tumor was curative. Histologic diagnosis was adrenal myelolipoma. No blood transfusion was required. CONCLUSIONS: A CT scan is very useful in the pre-operative diagnosis of adrenal myelolipoma with retroperitoneal hemorrhage. Watch and wait treatments before operation and nephrectomy with adhered tumor are safe and curative.  相似文献   
89.
BACKGROUND: Exercise intolerance of the hand after harvest of the radial artery is not well understood, although mild reductions of blood flow to the hand are reported. To ascertain its prevalence, patient symptoms implying potential exercise intolerance were evaluated by measuring transcutaneous oxygen pressure of the hand during grip exercise. For ascertaining predictive values, we verified ulnar flow reserve measured by Doppler ultrasonography before the harvest of radial artery. METHODS: Forty patients whose radial artery was harvested for coronary bypass graft, were interviewed and tested 1 year after operation, and their preoperative ultrasonographic data compared. RESULTS: Five patients (12.5%) had mild symptoms implying exercise intolerance. Exercise tests revealed severe decreases in tissue oxygenation in 7 patients (17.5%), but in accordance with symptoms (p = 0.0018). Tissue oxygenation in the operated hand was lower than in the nonoperated even in asymptomatic patients (p = 0.0011). Preoperative Doppler echography revealed that ulnar arteries of symptomatic patients were smaller (p = 0.0019) and carried lower blood flows during manual compression of the radial artery (p = 0.0004) compared with those of asymptomatic patients. Smaller ulnar arteries (less than 1.4 mm/m(2)) with poor flow reserves (less than 60 mL x min(-1) x m(-2) during radial compression) appear to indicate risks for exercise intolerance (p = 0.0004). CONCLUSIONS: More than 10% of patients after harvest of radial arteries had mild symptoms implying exercise-intolerance, which accorded with abnormal tissue oxygenation during grip exercise. Work habits of patients should be considered in radial harvest decisions, especially if preoperative Doppler echography indicates lower flow reserves for the ulnar artery.  相似文献   
90.
The subject was a 65-year-old woman with chest pain. An electrocardiogram revealed T-wave-inversion in leads III, aVF, V1-V5. 99mTc-tetrofosmin myocardial SPECT showed mildly reduced uptake in the anteroseptal wall and the apex. These findings suggested acute myocardial ischemia. Coronary angiography did not show any stenotic lesions, but diffuse coronary ectasia was noted in three vessels. Coronary flow velocity was remarkably reduced on coronary angiography. Epicardial coronary spasm was not provoked by ergonovine loading test. Left ventriculography showed diffuse hypokinesis. 123I-BMIPP myocardial SPECT showed mildly reduced uptake in the anteroseptal wall and the apex on the early images. But 4-hour delayed images showed an increase of 8% in myocardial 123I-BMIPP uptake. We treated this patient with ticlopidine and nicorandil. After drug therapy her symptoms and left ventriculography improved. 123I-BMIPP myocardial SPECT findings on the early images improved, whereas delayed images showed a decrease of 28% in myocardial 123I-BMIPP uptake after two weeks and 36% after four weeks. These dynamic changes in 123I-BMIPP findings might be a reflection of myocardial fatty acid metabolism in patients with acute myocardial ischemia. Delayed 123I-BMIPP myocardial SPECT images are useful for the assessment of fatty acid metabolism.  相似文献   
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