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1.
The authors have demonstrated previously that human plasma contains an inhibitor(s) of the enzymatic activity of renin. The purpose of this study is to identify the circulating renin inhibitor. Plasma initially was fractionated with preparative sephacryl S-300 chromatography. A fraction with low protein content inhibited the in vitro enzymatic activity of human renin by 76%. The inhibitory activity of this fraction was not altered by boiling and/or acidification. This fraction was applied to an affinity column, using purified mouse submaxillary renin as ligand. The inhibitor was recovered after elution with hypertonic NaCl. Linoleic acid, a previously identified renin inhibitor, was present in this fraction. The authors conclude that circulating linoleic acid inhibits renin. Conceivably, the overall activity of the renin-angiotensin-aldosterone cascade may be modified by alterations of plasma fatty acid concentrations.  相似文献   
2.
Perforative peritonitis is the most common surgical emergency in general surgical practice. Gastrointestinal perforation is the etiology in the vast majority of the patients. However, occasionally, other rare causes may be encountered. One such cause of peritonitis is spontaneous perforation of non-gravid uterus. Uterine perforation is a potential complication of any intrauterine procedure and may be associated with injury to surrounding blood vessels or viscera such as the urinary bladder or intestine. Spontaneous uterine perforation is rare and less than 50 cases have been reported in the English literature. We are presenting two such cases of spontaneous perforation of the uterus in elderly postmenopausal women which presented with generalized peritonitis and were clinically indistinguishable from gastrointestinal perforation.  相似文献   
3.
Therapy related acute lymphoblastic leukemia (t‐ALL) of B cell origin is rare and constitutes approximately 2% of all ALL. Previously compiled data on the complete cytogenetic analysis of 48 t‐B‐ALL cases suggested that MLL rearrangement at 11q23 gene locus is the most common abnormality. Philadelphia chromosome (Ph) and a normal karyotype were reported as the second and third most common karyotypes, respectively. We investigated cytogenetic karyotypes of six t‐B‐ALL cases with a pre‐B cell immunophenotype. Ph + t‐B‐ALL was noted in four of six patients previously treated with radiation and/or chemotherapy. In addition, one case demonstrated MLL rearrangement at 11q23 locus while one case demonstrated normal cytogenetic karyotype. Five of the six t‐B‐ALL patients had persistent leukemia following initiation of chemotherapy for secondary leukemia with survival ranging from 10 to 21 months. To our knowledge, only fourteen patients with Ph + t‐B‐ALL have been described in the literature. In the current study, three of four cases with Ph + t‐B‐ALL were associated with treated breast carcinoma while one patient was treated for Hodgkin lymphoma. All four patients had undergone radiation therapy. The results may indicate a plausible association between Ph+t‐B‐ALL and prior radiation exposure.  相似文献   
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There is an association between celiac disease (CD) and primary biliary cirrhosis, but there is little information regarding the association between CD and autoimmune cholangitis (antimitochondrial antibody-negative primary biliary cirrhosis). We describe a case of a 60-yr-old woman with chronic serum liver biochemistry elevations, recent onset of pruritus, and unexplained iron deficiency anemia. Liver biopsy was suggestive of stage 1 primary biliary cirrhosis, but serum antimitochondrial antibody testing was negative. Subsequent evaluation revealed CD based on markedly elevated antiendomysial antibody titers and characteristic histological features on mucosal biopsies. Initiation of a gluten-free diet led to resolution of iron deficiency anemia, pruritus, and elevated serum liver biochemistries. This suggests that CD may play a direct role in the development of autoimmune cholangitis. Additionally, normalization of hepatic biochemistries may be achieved without the use of immunosuppressive agents in some patients. CD should be considered in all patients diagnosed with autoimmune cholangitis as a gluten-free diet may avoid the need for immunosuppressive therapy in affected patients.  相似文献   
6.
This study investigated the protective effect of melatonin on dexamethasone (Dex), an extensively used anti‐inflammatory and immunosuppressive synthetic glucocorticoid, induced testicular oxidative stress and germ cell apoptosis in golden hamster. Hamsters were randomly divided into four groups (n = 7): group I – control; group II – melatonin treated (10 mg kg?1 day?1); group III – Dex treated (7 mg kg?1 day?1) and group IV – combination of Dex and melatonin. All the injections were administered intraperitoneally for seven consecutive days. The histopathological changes, specific biochemical markers, including antioxidative enzymes, plasma melatonin level and the markers for germ cell apoptosis were evaluated. Dex administration decreased antioxidant enzyme activities (SOD, CAT, GSH‐PX), plasma melatonin level and melatonin receptor (MT1) expression with a concomitant increase in lipid peroxidation (TBARS) and altered testicular histopathology which might culminate into increased germ cell apoptosis as evident from increased Bax/Bcl‐2 ratio and caspase‐3 expression. However, melatonin pre‐treatment enhanced enzyme activities for SOD, CAT, GSH‐PX with a simultaneous decrease in Bax/Bcl‐2 ratio and caspase‐3 expression. Our findings clearly suggest that melatonin improved defence against Dex‐induced testicular oxidative stress and prevented germ cell apoptosis, suggesting a novel combination therapeutic approach for management of male reproductive health.  相似文献   
7.
Patients with cirrhosis require endoscopic screening for large esophageal varices. The aims of this study were to determine the cost-effectiveness and patient preferences of a strategy employing abdominal computerized tomography (CT) as the initial screening test for identifying large esophageal varices. In a prospective evaluation,102 patients underwent both CT and endoscopic screening for gastroesophageal varices. Two radiologists read each CT independently; standard upper gastrointestinal endoscopy was the reference standard. Agreement between radiologists, and between endoscopists regarding size of varices was determined using kappa statistic. Cost-effectiveness analysis was performed to determine the optimal screening strategy for varices. Patient preference was assessed by questionnaire. CT was found to have approximately 90% sensitivity in the identification of esophageal varices determined to be large on endoscopy, but only about 50% specificity. The sensitivity of CT in detecting gastric varices was 87%. In addition, a significant number of gastric varices, peri-esophageal varices, and extraluminal pathology were identified by CT that were not identified by endoscopy. Patients overwhelmingly preferred CT over endoscopy. Agreement between radiologists was good regarding the size of varices (Kappa = 0.56), and exceeded agreement between endoscopists (Kappa = 0.36). Use of CT as the initial screening modality for the detection of varices was significantly more cost-effective compared to endoscopy irrespective of the prevalence of large varices. CONCLUSION: Abdominal CT as the initial screening test for varices could be cost-effective. CT also permits evaluation of extra-luminal pathology that impacts management.  相似文献   
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9.
Therapy-related myeloid neoplasms (t-MN) have a common origin in prior cytotoxic therapy and/or radiation. These neoplasms include therapy-related acute myeloid leukemia, myelodysplastic syndrome (t-MDS), and myelodysplastic/myeloproliferative neoplasms (t-MDS/MPN). Myeloid sarcoma (MS), on the other hand, is a rare disease manifesting as an extramedullary collection of immature cells of myeloid lineage. Rarer still is therapy-related MS (t-MS), which has not been adequately studied due to its rarity and its lack of recognition as a unique entity among other t-MN. Here, we report what is to our knowledge the first case series of t-MS, with the aim of investigating and establishing salient clinicopathological and molecular features of this entity.  相似文献   
10.
We have implemented the use of a small-scale, 7-vial Micro Freeze Dryer (MicroFD®; Millrock Technology, Inc.) that has the capability to accurately control heat transfer during lyophilization. We demonstrate the ability to fine-tune the MicroFD® vial heat transfer coefficient (Kv) to match the Kv of vials in a LyoStar III laboratory-scale unit. When the MicroFD® is run under conditions that match the Kv of the LyoStar III, the resulting lyophilization performance between scales results in equivalent product temperature profiles and critical quality attributes for the same drying process. The proposed workflow demonstrates how exploitation of Kv control in the MicroFD® enables cycle development of at-scale lyophilization processes using only 7 product vials. By changing the MicroFD® Kv, laboratory and, potentially, manufacturing cycles may be simulated using only 7 product vials for tremendous active pharmaceutical ingredient savings, as long as at-scale heat transfer coefficients are well characterized.  相似文献   
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