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OBJECTIVE: To analyze our experience with the management of retroperitoneal abscesses. PATIENTS AND METHODS: A retrospective study was made of 66 patients with retroperitoneal abscesses treated at our hospital from January 1975 to July 2001 for the purpose of analyzing the diagnosis and treatment of these rare infections. In each case, we analyzed patient characteristics, abscess location and origin, predisposing factors, clinical presentation, microbiology, radiographic findings, treatment, and outcome. RESULTS: In our series, the most frequent type of abscess was perinephric (45.4%), and the most frequent origin was the kidney (72.7%), generally renal lithiasis or previous urological surgery. Gram-negative bacilli were the microorganisms most often involved as causal agents of abscesses. CT had the best diagnostic performance (95%). Percutaneous drainage resolved the abscess in 86.3% of the patients in which it was used, compared with 87.5% for traditional surgical drainage. In 4 cases, the only treatment was administration of antibiotics. In all these cases the abscesses were smaller than 3 cm and patients were in good general condition. The mortality rate was excellent (1.5%), probably due to the low rate of comorbidity in our patients. CONCLUSIONS: Gram-negative bacilli were the most frequent microorganisms in our retroperitoneal abscesses. CT was the imaging technique that produced the most reliable and rapid diagnosis. Radiographically-guided percutaneous drainage was a safe and effective therapeutic alternative when used as definitive treatment or preoperatively.  相似文献   
93.
BACKGROUND: Historically, organ recovery rates in donors with cardiac arrest (CA) have been low, presumably from hemodynamic instability. We hypothesized that donor resuscitation has improved hemodynamic stability and organ recovery in CA donors, and that CA triggers ischemic preconditioning (IP) in liver grafts. METHODS: A total of 131 donor pairs with and without CA were matched in age, gender, and year of recovery. Hemodynamic stability was determined by vasopressor use. Abdominal and thoracic organs recovered and livers transplanted were compared between the groups. Liver graft function, injury, and IP benefit were examined by comparing liver chemistries after transplantation and postperfusion biopsies between recipients of grafts from both groups (n=40 each). RESULTS:Hemodynamic stability was similar in both groups, but recovery of thoracic organs was significantly lower in CA versus non-CA donors (35 vs. 53%, P<0.01). On the other hand, recovery rates of three or more abdominal organs from CA donors approached those of non-CA donors (77 vs. 87%, not significant). Although significantly fewer livers were transplanted from CA donors (69 vs. 85%, P<0.01), posttransplantation graft function and injury parameters were similar between the two groups, and CA did not appear to trigger IP. CONCLUSION: Compared with historical data, cardiovascular stability and abdominal organ recovery rates have improved considerably in CA donors. Liver grafts from CA donors function similarly to grafts from non-CA donors with no IP from CA. Our data support the increased use of livers and other organs from donors with CA.  相似文献   
94.
Naphthalmustine, 2-[2-[bis-(2-chloroethyl)amino]ethyl]-1H-benz[de]isoquinoline-1,3-dione (Compound 1) has been synthesized as a rationally designed new anticancer agent from N-(2-bromoethyl)naphthalimide. Its chemical alkylating activity exceeded that of nor-HN2 used as standard compound for comparison. Its antitumour efficacy was assessed in vivo in two murine ascites tumours namely Sarcoma-180 (S-180) and Ehrlich ascites carcinoma (EAC) by measuring the increase in median survival times (MST) of drug treated (T) over untreated control (C) mice. The clinical drug cyclophosphamide and the experimental compound mitonafide were used as positive controls for comparison. Compound 1 has displayed substantial and reproducible antitumoural activity in these tumours since very high remission times of treated animals were observed. Significant increase in the life span of mice bearing highly advanced tumour for 10 days before the drug challenge was also noted after its treatment. Its LD50 value was 200 mg/Kg by single i.p. injection. Its toxicity was also assessed in vivo in normal and in S-180 bearing mice by measuring drug-induced changes in hematological parameters, femoral bone marrow and splenic cellularity sequentially on days 9, 15 and 21 following drug treatment at the optimum dose of 12 mg/kg from day 1 to 7. The results indicated that the compound did not adversely affect hematopoiesis. Drug-induced hepatotoxicity and nephrotoxicity were also evaluated on those days but no such toxicities were detected. Naphthalmustine inhibits the synthesis of DNA and RNA in S-180 tumour cells. It was further screened in vitro in 4 different human tumour cell lines but no significant activity was observed in those lines.  相似文献   
95.
BACKGROUND: Over 6 million people live in areas of West Bengal, India, where groundwater sources are contaminated with naturally occurring arsenic. The key objective of this nested case-control study was to characterize the dose-response relation between low arsenic concentrations in drinking water and arsenic-induced skin keratoses and hyperpigmentation. METHODS: We selected cases (persons with arsenic-induced skin lesions) and age- and sex-matched controls from participants in a 1995-1996 cross-sectional survey in West Bengal. We used a detailed assessment of arsenic exposure that covered at least 20 years. Participants were reexamined between 1998 and 2000. Consensus agreement by four physicians reviewing the skin lesion photographs confirmed the diagnosis in 87% of cases clinically diagnosed in the field. RESULTS: The average peak arsenic concentration in drinking water was 325 microg/liter for cases and 180 microg/liter for controls. The average latency for skin lesions was 23 years from first exposure. We found strong dose-response gradients with both peak and average arsenic water concentrations. CONCLUSIONS: The lowest peak arsenic ingested by a confirmed case was 115 microg/liter. Confirmation of case diagnosis and intensive longitudinal exposure assessment provide the basis for a detailed dose-response evaluation of arsenic-caused skin lesions.  相似文献   
96.
The role of the central nucleus of the amygdala in nociception--conditioned and unconditioned aversion--was studied. Rats received microinjection of vehicle or the N-type Ca2+ channel blocker omega-conotoxin GVIA (0.2 microg/250 nl) into the central amygdaloid nucleus prior to intra-plantar injection of formalin, ultrasound exposure or immediately prior to the acquisition phase of an aversive conditioning trial. Intra-amygdala omega-conotoxin GVIA resulted in an earlier onset of nociceptive response to formalin and increased nociceptive behaviour during the first 5 min. Omega-conotoxin GVIA significantly reduced conditioned freezing behaviour with no effect on ultrasound-induced unconditioned aversive behaviour. These data indicate that N-type Ca2+ channels in the central amygdaloid nucleus play a role in mediating behavioural responses to nociceptive and conditioned aversive stimuli.  相似文献   
97.
We present a case of retroperitoneal fibrosis treated with a renal autotransplantation in a patient inicially treated with endourologic measures and corticotherapy without success. The extense ureteral affectation was the indication to carry out an autotransplant. The follow-up is of nine years, with the function of the renal unity still preserved. We checked the literature for the therapeutic possibilities, medical as much as surgical, of the retroperitoneal fibrosis with special attention to the usage of the refractory IRF to other treatments. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
98.
In women with hypothyroidism, levothyroxine (LT) requirements after delivery are assumed to return to prepregnancy values. The occasional observation of discordances prompted this study. Forty-one women (31 receiving LT replacement therapy and 10 receiving suppressive therapy for thyroid carcinoma) were followed during the first year after delivery. A control group of 31 nonpregnant women with hypothyroidism (n = 21) or thyroid carcinoma (n = 10) were also followed during a similar period. Twenty-three patients of 41 (56.1%) had discordant requirements at follow-up after delivery vs. 3 of 31 in the control group (9.7%; P < 0.001). The patterns of discordance in the postdelivery group were hyperthyroidism in 12, increase in LT dose in 5, hyper- and hypothyroidism in 5, and recurrence of Graves' disease in 1 women. Those in the control group were increase in LT dose, hyperthyroidism, and hypo- and hyperthyroidism. The rate of patients with discordant prepregnancy-postpartum LT doses was higher in the noncarcinoma subgroup (67.7% vs. 20.0%; P < 0.01), whereas in the control group, both subgroups displayed a similar rate of discordance (9.5% vs. 10%; P = NS). In conclusion, this study documents that women with hypothyroidism antedating pregnancy display changes in LT requirements in the first year after delivery that suggest postpartum thyroiditis.  相似文献   
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