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121.
Renal hypertrophy is a common consequence of diabetes mellitus that precedes and possibly accounts for the increased glomerular filtration rate. We have postulated that the glucose-mediated increase in the intracellular concentration of sodium [Na]i initiates the chain of events leading to the increase in cell size and eventually cell number. Experiments were conducted on Sprague-Dawley rats made diabetic by the intravenous injection of 45 mg/kg body wt of streptozotocin dissolved in a 5 mM citrate buffer solution. Control animals were injected with the vehicle alone. Ninety-six hours and 11 weeks later, measurements of [Na]i were done by NMR spectroscopy on suspensions of proximal tubules, using dysprosium tripolyphosphate as an extracellular shift reagent. At 96 hours after the induction of the diabetes, there was a 60% increase in [Na]i compared to control (P less than 0.01). No further increase in [Na]i was observed during the subsequent 11 weeks of observation. Addition of ouabain (1.0 mM) resulted in a fourfold increase in [Na]i in tubules from control animals, and a 2.5-fold increase in tubules from 96-hour diabetic rats. Ouabain-inhibitable Na+-K+-ATPase activity was substantially higher in the renal tubules of diabetic rats, the increase being proportional to that of [Na]i. In order to ascertain the effect of hyperglycemia on [Na]i, proximal tubules prepared from kidneys of normal and diabetic rats were exposed to low (5 mM) and high (25 mM) concentration of glucose in the media.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
122.
Food systems are complex and inhomogeneous in nature. Ultrasonic propagation velocity in the food systems, in this case processed milk cream and vegetable oils, is studied. Ultrasonic properties of the food systems are similar to those of complex biological tissues. The presence of vegetable oil as an adulterant in the processed milk cream is detected with the help of a double-probe-through-transmission ultrasonic technique. The present study helps to maintain quality control of various food systems, particularly with regard to their adulteration, if any. 相似文献
123.
Dipyridamole is superior to dobutamine for thallium stress imaging: a randomised crossover study.
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E. B. Kumar S. A. Steel S. Howey J. L. Caplin C. P. Aber 《Heart (British Cardiac Society)》1994,71(2):129-134
OBJECTIVE--To assess the value of dobutamine over dipyridamole as a pharmacological stressing agent in myocardial perfusion imaging with thallium-201. DESIGN--Stress and redistribution tomographic images were taken in a group of patients in a randomised crossover study of both agents. The scans were scored to give a value for the stress and redistribution images and a reversibility score (redistribution--stress). All patients had coronary angiography that was also scored. Differences between the two agents were compared by a paired t test. PATIENTS--30 patients aged 51-70 years with chest pain thought to be caused by myocardial ischaemia. 11 had had previously myocardial infarction. RESULTS--Dipyridamole caused adverse symptoms in six patients whereas dobutamine caused symptoms in 21 patients (chi 2 = 15.15, p < 0.0001). Dobutamine stress took considerably longer than dipyridamole (31 v 6 minutes) and cost more (17 pounds v 1.50 pounds). There were no significant differences between the agents in terms of total stress or redistribution scores, but regional analysis showed that dipyridamole showed significantly more defects during stress at the apex and lateral wall (p < 0.05), with no significant difference at redistribution. Dipyridamole stress also caused significantly more reversible defects at the apex (p < 0.05) and gave a better correlation than dobutamine with coronary score (dipyridamole r = 0.80, p < 0.001 v dobutamine r = 0.64, p < 0.001). In six patients who had continued to take beta blockers the results of dobutamine stress did not correlate with coronary score, r = 0.34 (NS), whereas dipyridamole studies were not affected. CONCLUSION--Compared with dobutamine, dipyridamole was as effective in producing overall perfusion defects and more effective in provoking defects at the apex and lateral segment. The dipyridamole study correlated better with coronary score and was not affected by concurrent beta blocker treatment. It was also better tolerated by the patients, was less time consuming, and was much cheaper. 相似文献
124.
Behavioral symptomatology in dementia of the Alzheimer type 总被引:1,自引:0,他引:1
A Kumar E Koss D Metzler A Moore R P Friedland 《Alzheimer disease and associated disorders》1988,2(4):363-365
125.
S. Kumar N. H. Dar M. Ashraf S. C. Sharma V. Maheshwari 《Indian journal of otolaryngology and head and neck surgery》2004,56(1):37-39
We report a cast of ossifying fibroma of the nose, arising from the bony septum and extending into the nasophaynx in a 2 yrs.
old child presenting with features of obstructed nose. 相似文献
126.
Everson L. A. Artifon Airton Z. Rodrigues Sergio Marques Bhawna Halwan Paulo Sakai Claudio Bresciani Atul Kumar 《Journal of gastrointestinal surgery》2007,11(12):1686-1691
Background Exploratory laparoscopy is commonly undertaken in patients with highly suspicious biliary and pancreatic lesions to facilitate
diagnosis and staging cancer is present. If an unresectable tumor is identified, a second endoscopic procedure may be required
do deploy a self-expandable metal stent (SEMS) for palliation. As endoscopic retrograde cholangio pancreatography (ERCP) may
be unsuccessful in up to 20% of patients, we evaluated the feasibility and safety of deployment of self-expandable metal stents
at the same time as the initial laparoscopy.
Patients and Methods A total of 23 eligible patients (8 male and 15 female) with malignant obstruction of the common bile duct underwent deployment
of SEMS at laparoscopy. Primary outcome measure was the successful laparoscopic deployment of stent and secondary outcome
measure was complications rates.
Results Indications for stent deployment were unresectable pancreatic cancer in 18, cholangiocarcinoma in two, neuroendocrine tumor
in one and ampullary adenocarcinoma in two patients. The median age was 73 years (range 49–93). Twenty-two of 23 stents were
deployed successfully: 17 stents were deployed transcystically and five via a choledochotomy. Median times for laparoscopic
exploration and SEMS deployment were 165 min (range 105–230) and 20 min (range 10–50), respectively. Pre- and post-procedures
median total bilirubin were 9.4 mg/dl (range 5.4–17.5) and 4.0 (range 2.6–7.1). The median size of the pancreatic mass was
3 cm (range 2–5 cm) and that of the common bile duct (CBD) from 9.2 mm (range 7.2–17.4). The mean duration of laparoscopy
was 170 min (range 120–230 min) and that for stent deployment 23 min (range 10–50 min). Complications included bleeding, obstruction,
and wound infection. Bleeding occurred on day 7 in two patients and on day 30 in one patient; bleeding occurred at the gastrojejunal
anastomosis site and was successfully treated with endoscopic hemostasis. A total of three stent obstructions were identified:
one each at 60, 90, and 120 days follow-up. All complications were successfully managed endoscopically. There were a total
of seven deaths, six as a result of progressive cancer and one of surgical wound infection and ensuing complications.
Conclusion This study demonstrates that laparoscopic deployment of self-expandable metal bile duct stents is feasible and safe. This
option appears to be a reasonable option in patients with inoperable malignant obstruction of the distal common bile duct. 相似文献
127.
Khaidem Ibochouba Singh Jigme Tenzing Shartsho Waikhom Ruhini Kumar Singh Raj Kumari Tamphasana Devi Ahongshangbam Meina Singh 《Indian journal of hematology & blood transfusion》2007,23(3-4):116-118
Two children out of three siblings of a family presented with tiredness, fatigue, and breathlessness for more than 6 months. Examination of peripheral blood smear, bone marrow aspirate, and a positive acidified serum test (HEMPAS) revealed these children to be a case of congenital dyserythropoietic anemia type II. This case is reported because of its rarity. 相似文献
128.
Evidence-Based Integrative Medicine - 相似文献
129.
130.
Abstract A young male motorcyclist presented to the Pelvic Unit with an open-book fracture of his pelvis and an acute obstructed direct
inguinal hernia. He was managed operatively and made an excellent recovery. Traumatic abdominal wall hernias are rare. This
is a unique combination of injuries that the trauma surgeon should be aware of. 相似文献