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1.
We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca2+ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca2+ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion.  相似文献   
2.
Two patients presenting with signs and symptoms suggestive of nerve root compression secondary to extradural masses were found to have ligamentum flavum hematomas. Both patients had neurological deficits preoperatively and regained normal function postoperatively. There was no significant antecedent injury in either case. The symptom course was longer than that for spontaneous epidural hematoma. In one case, there was remodeling of bone, initially suggesting either infection or tumor.  相似文献   
3.
Although the numbers of newly reported diagnoses of AIDS decreased in the 1990s, it is not clear whether they reflect a decreasing number of new HIV infections. Direct measurement of HIV incidence through follow-up cohort studies is difficult and costly. We estimated HIV incidence and trends in incidence among men who have sex with men (MSM) and heterosexual men and women at clinics for sexually transmitted diseases (STDs) by using a recently developed serologic testing algorithm that requires only a single blood specimen. Cross-sectional anonymous serosurveys were conducted at 13 STD clinics in nine cities in the United States from 1991 through 1997. Before anonymous HIV testing, demographic and clinical information was abstracted. Of 129,774 specimens tested, 362 (0.28%) were from persons estimated to be recently infected. Incidence among MSM was 7.1% (95% confidence interval (CI): 4.8-10.3), 14 times higher than that among heterosexuals, which was 0.5% (CI: 0.4- 0.7). Incidence among MSM and heterosexuals remained unchanged during the time studied. Decreasing rates of new AIDS diagnoses in the 1990s do not reflect stable rates of new HIV infections among MSM and heterosexual patients attending these clinics.  相似文献   
4.
5.
Renal transplant (RT) is now a therapy of choice for end stage renal disease (ESRD). The Nephrology Unit, Asvini started functioning in Dec 90 and to date 1298 sittings of hemodialysis have been given to 45 patients. Of these, 35 were in ESRD and 11 patients underwent renal transplantation at this hospital during the period Jan 91 – Dec 93. One patient expired after 18 months of transplantation due to infection. Early experience in screening patients for RT, use of immunosuppression, management of rejection episodes and protocol are presented with special emphasis on its relevance to the Armed Forces.KEY WORDS: Transplantation, Renal Failure, Immunosuppression, Rejection  相似文献   
6.
It is not always necessary or desirable for a block to extend over a wide area, involve the sympathetic system or act bilaterally. Many blocks are capable of providing excellent analgesia in a limited area of the body and with minimal systemic effect. Peripheral nerve blocks are simple to perform, provide excellent analgesia and have a historical record of safety. In general, appropriate blocks exist for almost all area of the body. Since analgesic requirements and duration of a single dose local anesthetic vary greatly, patients can be expected to obtain better analgesia if they could control the amount and timing of local analgesic medication by PCRA. A new technique is described that allows the patient to self-administer a prescribed dose of local anesthetic at home.  相似文献   
7.
BACKGROUND: Research has focused mainly on the relationship of zinc and copper contents and physical stresses like running, cycling, etc. It has also been reported that other forms of stresses change the concentration of these trace elements in humans. However,there are no reports on the effects of high altitude induced hypoxic stress on the plasma levels of these metals. Since hypoxia is one of the important stresses, we considered it appropriate to observe the changes in the levels of zinc and copper concentrations and in certain related zinc and copper enzymes and hormones in the plasma of human volunteers on acute induction to high altitude. From these findings, we intended to ascertain whether supplementation of these trace elements would be required for optimal health under such conditions. HYPOTHESIS: On acute induction to hypoxia, contents of these trace elements may change as the requirements of stressed organs and tissue may increase. Hence, further supplementation may be beneficial under hypoxic stress for better adaptability. METHOD: Volunteers were divided into two groups: with and without zinc and copper salt supplementation. Blood samples were collected at sea level and on induction to acute hypoxia on days 3 and 10. Trace mineral contents and their related enzyme (alkaline phosphatase) and hormone (ceruloplasmin) levels were determined in plasma samples. RESULTS: Plasma zinc contents were significantly reduced upon induction to high altitude in the non-supplemented group, but not in the zinc-supplemented group. Alkaline phosphatase activity increased significantly upon induction to the high altitude stress. The enzyme activity remained elevated up to day 10 of the stress. Plasma copper contents and ceruloplasmin activity did not change upon induction to high altitude. CONCLUSION: Under hypoxic stress, circulating levels of zinc and alkaline phosphatase in plasma changed appreciably as plasma zinc was transported into the organs and tissues. However, circulating levels of copper and ceruloplasmin in plasma did not change, indicating no extra supplementation of copper is required under hypoxic stress.  相似文献   
8.
PURPOSE: In vitro study of the enzymes involved in aerobic, anaerobic and hexose monophosphate shunt in ultraviolet radiation exposed mice lenses. METHOD: Of the selected enzymes, lactic dehydrogenase (LDH) was representative of anaerobic glucose oxidation, succinic dehydrogenase (SDH) of the aerobic oxidation, and Glucose-6-phosphate dehydrogenase (G-6-PDH) of the Hexose Monophosphate (HMP) shunt. Other enzymes studied were ATPase and glutathione reductase (GR). RESULTS: Experiments with mice lenses in vitro showed that transparent lens became opaque following UV-irradiation at 360 nm. Opacification of the lens was accompanied by a change in enzyme activities for energy metabolism. CONCLUSION: These changes were progressive in a manner analogous to sequential morphological changes, which would be crucial in maintaining lens transparency.  相似文献   
9.
In the present investigation thyroidal accumulation of radioiodine and its release were assessed by direct testing of thyroid function using radioactive iodine, in vivo, in sea level residents intermittently exposed to hypobaric hypoxia. Thyroidal accumulation of radioiodine and its turnover were examined daily for 14 days. Twelve healthy human male volunteers were divided into three groups, with an equal number of individuals in each group. A decompression chamber was used to expose each group of subjects to hypoxic conditions at a simulated altitude of 3810 m for 8 h/day for 14 days. An oral dose of 25Ci iodine-131 was administered to each individual of the first group immediately before the initiation of intermittent hypoxia. The second group of subjects received a tracer dose at the beginning of the 4th day of the 14 days, intermittent exposure to hypoxia, while the third group received the tracer dose 1 week after the completion of the exposure. Control studies were carried out on the subjects before they were subjected to the experimental conditions. Thyroidal accumulation of131I in experimental subjects during the hypoxic state and in the post-hypoxic state was higher than in the control studies. The pattern of accumulation during exposure to hypoxia and in the post-hypoxic state showed multiple peaks of radioactive iodine uptake (PRAIU), a unique feature. The multiple PRAIU by the thyroid in experimental subjects were sharp and of short duration, reflecting an increased rate of13I release from the thyroid. Control subjects had a single PRAIU by the thyroid 24 h after the administration of tracer.  相似文献   
10.
Forty-four-year-old male with ulcerative colitis (UC) for 11 years reported frequent relapse despite daily sulfasalazine 4 g, azathioprine 125 mg, and rectal 5-aminosalicylic acid. Repeated use of corticosteroids led to cataract. At enrollment, he was passing eight stools a day with blood with a Mayo score of 9 (3+1+3+2). Stool was negative for ova/cysts/acid fast bacilli and Clostridium difficile toxin assay. Rectal biopsy showed cryptitis, crypt abscess, and crypt distortion with no inclusion bodies, and cytomegalovirus DNA was negative. Following informed consent and approval from IEC, three sessions of fecal microbiota transplant (FMT) were performed at intervals of 2 weeks. The donor was a 34-year-old relative with no history of gastrointestinal illness, no use of antibiotics over 3 months, and free from transmissible disease as per standard protocol. At colonoscopy, 350 mL of blended and filtered donor stool, drawn into seven syringes of 50 cm3, was instilled from terminal ileum to sigmoid. Follow up sigmoidoscopy and rectal biopsy were done monthly for 6 months. There was symptomatic, colonoscopic, and histopathological improvement with the Mayo scores of 4.1 and 0 at 4.8 and 12 weeks post FMT. Azathioprine and sulfasalazine were tapered sequentially between months 4 and 6 of FMT. He remains in clinical and endoscopic remission 8 months after FMT and 2 months after withdrawal of all medication. Colonoscopic FMT may be effective in inducing drug-free remission in patients with active UC.  相似文献   
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