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81.
PURPOSE: We determine the relative sensitivities of cytology and fluorescence in situ hybridization (FISH) for the detection of urothelial carcinoma. MATERIALS AND METHODS: A mixture of fluorescent labeled probes to the centromeres of chromosomes 3, 7 and 17, and band 9p21 (P16/CDKN2A gene) was used to assess urinary cells for chromosomal abnormalities indicative of malignancy. A total of 280 urine specimens from 265 patients, including 150 with a history of urothelial carcinoma and 115 without a history of urothelial carcinoma, were analyzed. FISH analysis was performed without prior knowledge of clinical findings, that is biopsy, cystoscopy and cytology results. A positive result was defined as 5 or more urinary cells with gains of 2 or more chromosomes. RESULTS: A total of 75 biopsies showed urothelial carcinoma at FISH analysis among the 265 patients. The sensitivity of urine cytology for pTa (36 cases), pTis (18) and pT1-pT4 (15) tumors was 47%, 78% and 60%, respectively, for an overall sensitivity of 58%. The sensitivity of FISH for pTa (37 cases), pTis (17) and pT1-pT4 (19) tumors was 65%, 100% and 95%, respectively, for an overall sensitivity of 81%. FISH was significantly more sensitive than cytology for pTis (p = 0.046), pT1-pT4 (p = 0.025), grade 3 (p = 0.003) and all tumors (p = 0.001). The specificity of cytology and FISH among patients without cystoscopic evidence of urothelial carcinoma and no history of urothelial carcinoma was 98% and 96%, respectively (p = 0.564). CONCLUSIONS: The sensitivity of FISH for the detection of urothelial carcinoma is superior to that of cytology, and the specificity of FISH and cytology for urothelial carcinoma are not significantly different. Further prospective studies are required but FISH has the potential to improve significantly the management of urothelial carcinoma.  相似文献   
82.
Background  Pancreatic redo procedures belong to the most difficult abdominal operations because of altered anatomy, significant adhesions, and the potential of recurrent disease. We report on our experience with 15 redo procedures among a series of 350 consecutive pancreatic operations. Patient and Methods  From January 1, 2004 to May 31, 2006 a total of 350 patients underwent pancreatic surgery in our department. There were 15 patients identified who had pancreatic redo surgery for benign (14) or malignant (1) disease. Perioperative parameters and outcome of 15 patients undergoing redo surgery after pancreatic resections were evaluated. Results  Operative procedures included revision and redo of the pancreaticojejunostomy after resection of the pancreatic margin (6), completion pancreatectomy (3), conversion from duodenum-preserving pancreatic head resection to pylorus-preserving pancreaticoduodenectomy (3), classic pancreaticoduodenectomy after nonresective pancreatic surgery (1), redo of left-sided pancreatectomy (1), and classic pancreaticoduodenectomy after left-sided pancreatectomy (1). Histology revealed chronic pancreatitis in 14 and a mucinous adenocarcinoma of the pancreas in 1 patient. Median operative time was 335 min (235–615 min) and median intraoperative blood loss was 600 ml (300–2,800 ml). Median postoperative ICU stay was 20 h (4–113 h) and median postoperative hospital stay was 15 days (7–30 days). There was no perioperative mortality and morbidity was 33%. Conclusion  Pancreatic redo surgery can be performed with low morbidity and mortality. Redo surgery has a defined spectrum of indications, but to achieve good results surgery may be performed at high-volume centers.  相似文献   
83.
Cadmium is a toxic heavy metal element, which probably cause infertility by impairment in spermatogenesis. The present work aimed (i) to study the toxic effect of cadmium on spermatogenesis in rat, as well as (ii) the protective effect of Crocus sativus L. on cadmium‐intoxicated rats. Cadmium chloride was administered intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. Crocus sativus L. was pre‐treated in both of control and cadmium‐injected rats. Animals were sacrificed on day 17 after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank's balanced salt solution for the evaluation of sperm count and viability, and left testis was fixed in 10% formalin for histological evaluation. Following contamination with cadmium, a decrease was observed in the number and viability of cauda epididymis sperm, which were increased by Crocus sativus L. pre‐treatment (P < 0.05). In addition, cadmium decreased both cell proliferation and Johnsen Scores in the seminiferous tubules, which were reversed by Crocus sativus pre‐treatment (P < 0.05). Furthermore, cadmium‐induced decrease in the amount of free serum testosterone as well as an increase in lipid peroxidation activity in the testicular tissue was reversed by Crocus sativus L. (P < 0.05). These findings may support the concept that Crocus sativus L. can improve the cadmium toxicity on spermatogenesis.  相似文献   
84.

Background

We used the PCR technique based on the abovementioned primer pair and sequencing to demonstrate the Theileria infection in the sheep samples collected from Sultanate of Oman.

Methods

According to the frame work of “integrated control of ticks and tick borne diseases in globalized world managed by EU-ICTTD-3 project, the samples from blood, liver, spleen, lymph node and lung were sent to the laboratory of Iranian Research Center for Ticks and Tick-borne Diseases (IRCTTD). Samples from blood smear and impression smears from liver, spleen, lymph node, and lung were analyzed by Geimsa staining. The DNA was extracted from the abovementioned samples and analyzed by PCR technique using specific primers derived from the nucleotide sequences of 18S rRNA gene of T. lestoquardi, which can amplify the common region in other Theileria and Babesia spp. Subsequently the amplified DNA was sequenced.

Results

The analysis of blood smears of the sheep was negative for piroplasmosis performed through the Giemsa staining. The impression smears prepared from liver, spleen, lymph node, and lung showed suspicious structures mimicking Theileria schizonts in some cells. The results showed an expected PCR product of 428 bp in length, which is specific for Theileria spp. The PCR products were subsequently sequenced. The corresponding nucleotide sequence is registered under accession number JF309152 in GenBank. The sequence alignment in GenBank showed that the PCR products had 99% homology to the known T. lestoquardi registered under accession number AF081135 in the GenBank.

Conclusion

Oman sheep are highly susceptible for Theileria infection and the infected sheep mostly die before the microschizonts or erythrocytic form of Theileria appears in the nucleated or erytrocytic cells respectively.  相似文献   
85.
86.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
87.

Background

Achievement of maximal hyperemia of the coronary microcirculation is a prerequisite for the measurement of fractional flow reserve (FFR). Intravenous adenosine is considered the standard method, but its use in the catheterization laboratory is time consuming and expensive compared with intracoronary adenosine. Therefore, this study compared different high, intracoronary doses of adenosine for the potential to achieve a maximal hyperemia equivalent to the standard intravenous route.

Methods

FFR was assessed in 50 patients with 50 intermediate lesions during cardiac catheterization. FFR was calculated as the ratio of the distal coronary pressure to the aortic pressure at hyperemia. Different incremental doses of intracoronary adenosine (60, 90, 120, and 150 μg as boli) and a standard intravenous infusion of 140 μg/kg/min were administered in a randomized fashion.

Results

Different incremental doses of intracoronary adenosine were well tolerated, with fewer systemic adverse effects than intravenous adenosine. At baseline, there were no significant differences for mean aortic and distal coronary pressure or heart rate in the different adenosine doses and routes. FFR decreased with increasing adenosine doses, with the lowest values observed with the 150-μg intracoronary bolus and 140-μg/kg/min dose of intravenous adenosine. All intracoronary doses, except the 150-μg bolus, resulted in mean FFR values that were significantly (P <.05) higher than FFR after the administration intravenous adenosine. Furthermore, 5 patients (10%) with a FFR value >0.75 and 3 subjects (6%) with a FFR value >0.80 who received a 60-μg intracoronary bolus reached a value below the cutoff point of 0.75 with the intravenous administration.

Conclusions

This study suggests a dose-response relationship on hyperemia for intracoronary adenosine doses >60 μg. The administration of very high intracoronary adenosine boli is safe and associated with fewer systemic adverse effects than standard intravenous adenosine. However, intravenous adenosine administration with 140 μg/kg/min produced a more pronounced hyperemia than intracoronary adenosine in most patients and should be the preferred mode of application for the assessment of FFR.  相似文献   
88.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
89.
BACKGROUND: The danger of bacteremia due to contaminated platelets is not well known. There are also no established guidelines for the management of febrile reactions after platelet transfusion. STUDY DESIGN AND METHODS: To determine the risk of symptomatic bacteremia after platelet transfusion, 3584 platelet transfusions given to 161 patients after bone marrow transplantation were prospectively studied. Platelet bags were routinely refrigerated for 24 hours after transfusion. Septic work-up was initiated for a temperature rise of more than 2 degrees C above the pretransfusion value within 24 hours of platelet transfusion or a temperature rise of more than 1 degree C that was associated with chills and rigor. Diagnosis of bacteremia after platelet transfusion was made only when the pairs of isolates from the blood and the platelet bags were identical with respect to their biochemical profile, antibiotic sensitivity, serotyping, or ribotyping. RESULTS: Thirty-seven febrile reactions, as defined above, occurred. Bacteremia subsequent to platelet transfusion was diagnosed in 10 cases. There was a 27-percent chance (95% CI, 15–43%) that these febrile reactions represented bacteremia that resulted from platelet transfusion. For a subgroup of 19 patients with a temperature rise of more than 2 degrees C, the risk of bacteremia was 42 percent (95% CI, 23–64%). Septic shock occurred in 4 of the 10 bacteremic patients. A rapid diagnosis was possible because the involved bacteria were demonstrated by direct Gram stain of the samples taken from the platelet bags of all 10 patients. CONCLUSION: Significant febrile reactions after platelet transfusion are highly likely to be indicative of bacteremia. Routine retention of platelet bags for subsequent microbiologic study was useful in the investigation of these febrile reactions. Empiric antibiotic therapy is indicated.  相似文献   
90.
Transient immunity to the intestinal parasite Trichinella spiralis can be transferred from the mother to the neonate during lactation. The goal of this study was to determine whether maternal ingestion of ethanol during pregnancy and lactation inhibited expression of anti- T. spiralis immunity in nursing pups. Groups of female rats were infected with 1000 T. spiralis L1 larva, mated, and fed either ethanol-containing or isocaloric liquid diets and maintained on diets through pregnancy and lactation or were fed the liquid diets for 30 days before T. spiralis infection, mated, and maintained on diets through pregnancy and lactation. Pups were challenged orally with 200 T. spiralis larva at 14 days postdelivery (preweaning period) or 21 days postdelivery (postweaning period) and were sacrificed either 3 or 8 days after respective challenge. Intestinal worm counts and serum titers of anti-T. spiralis IgG antibodies were determined for each pup. No difference in the number of intestinal worms between pups of ethanol-treated and pair-fed dams that received ethanol diet after T. spiralis infection was observed in the preweaning period. This was also true of pups from the dams sacrificed at 3 days after challenge in the postweaning period. However, similar pups sacrificed at 8 days after challenge showed significantly higher worm counts (decreased immunity) relative to their pair-fed controls. Pups of dams that received ethanol containing diet 30 days prior to T. spiralis-infection showed significantly higher numbers of intestinal worms relative to pair-fed pups at both the preweaning and postweaning periods.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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