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81.
To assess the efficacy of quinolones in the prophylaxis of infections in neutropenic patients with acute non-lymphocytic leukemia, and to evaluate the emergence of quinolone resistance in two University Hospitals in Brazil, we retrospectively compared 101 consecutive episodes of neutropenia managed with quinolone prophylaxis between 1989 and November 1993, and 26 previous episodes without prophylaxis, and reviewed the results of in vitro sensitivity of Gram-negative strains to quinolones in the same period. Prophylaxis with quinolones resulted in less episodes of bacteremias (21% vs. 69%, p=10(-7)), including Gram-negative bacteremias (6% vs. 38%, p=10(-5)), with no statistically significant difference in the death rate (18% vs. 31%, p=0.14, 95% confidence interval -6-32). The resistance of Gramnegative strains to quinolones rose from 7% to 18% between 1990 and 1993 (p=10(-5)). The resistance against ceftazidime and amikacin, the agents used in the empirical antibiotic therapy, increased in the same proportion as the quinolones. Given the limited benefit of quinolones as prophylaxis and the increasing number of quinolone-resistant Gram-negative strains observed in our hospitals, the use of quinolones as prophylaxis must be seriously questioned. A stricter control of the use of quinolones in these hospitals might decrease resistance.  相似文献   
82.
Background: The complications of the gastric pouch in gastric bypass surgery are well known. Since the first report of this surgery 30 years ago, new technical aspects that make it safer and more effective have been implemented. Methods: As a modification of gastric bypass, the authors have performed 305 vertical banded gastroplasty-gastric bypass procedures. Two groups of patients underwent the procedure: Group I (n = 206) without a limb of jejunum interposed between the gastric pouch and the excluded stomach, and Group II (n = 99) with a limb of jejunum interposed between the pouch and the stomach. The results regarding excess weight loss and complications of the gastric pouch during the first year after surgery were compared. Results: Age, sex, initial weight, body mass index, and percentage of ideal weight were similar in both groups. Excess weight loss was also similar. The complications in Group I were 1 leak, 3 left subphrenic abscesses, 2 erosive gastritis with bleeding, 1 stenosis of the gastrojejunostomy, 1 perforated ulcer, and 4 marginal ulcers with bleeding. Two patients in Group II developed bleeding from the staple-line. Conclusions: These preliminary data suggest that complications of the gastric pouch can be reduced by interposing a limb of jejunum between the pouch and the excluded stomach. This is an early experience; long-term results are pending.  相似文献   
83.
The mutation in the hypoxanthine-guanine phosphoribosyltransferase (HPRT) gene has been determined in two brothers affected with Lesch-Nyhan syndrome. Female members of the family who are at risk for being heterozygous carriers of the HPRT mutation were also studied to determine whether they carry the mutation. DNA sequencing revealed that the boys' mother is heterozygous for the mutation in her somatic cells, but that three maternal aunts are not heterozygous. Such carrier information is important for the future pregnancy plans of at-risk females. The mutation, an A-->T transversion at cDNA base 590 (590A-->T), results in an amino acid change of glutamic acid to valine at codon 197, and has not been reported previously in a Lesch-Nyhan syndrome male. This mutation is designated HPRTBrasil.  相似文献   
84.
While prevalence of uterine leiomyoma is high, its presentation affecting the urinary tract is uncommon. We contribute the cases of two adult women with symptoms of nephritic colic and urinary retention. Etiology was acute obstruction of the urinary tract due to previously asymptomatic urine myomas. Management in both patients was surgery, using hysterectomy to resolve the urinary obstruction. A brief review of the literature is included.  相似文献   
85.
Oral administration of an infusion of lemongrass (Cymbopogon citratus) fresh leaves to rats produced a dose-dependent analgesia for the hyperalgesia induced by subplantar injections of either carrageenin or prostaglandin E2, but did not affect that induced by dibutyryl cyclic AMP. These results indicate a peripheral site of action which was confirmed with the essential oil obtained by steam distillation of the leaves. Silica gel column fractionation of the essential oil allowed the identification of myrcene as the major analgesic component in the oil. Identification of the components was made by thin-layer chromatography and checked by mass spectrometry. The peripheral analgesic effect of myrcene was confirmed by testing a standard commercial preparation on the hyperalgesia induced by prostaglandin in the rat paw test and upon the contortions induced by intraperitoneal injections of iloprost in mice. In contrast to the central analgesic effect of morphine, myrcene did not cause tolerance on repeated injection in rats. This analgesic activity supports the use of lemongrass tea as a "sedative" in folk medicine. Terpenes such as myrcene may constitute a lead for the development of new peripheral analgesics with a profile of action different from that of the aspirin-like drugs.  相似文献   
86.
87.
Sialyl-Tn antigen (STn) is a mucin-type carbohydrate normally present in goblet cells of small and large bowel. STn expression has been demonstrated to occur in complete and incomplete intestinal metaplasia as well as in many carcinomas but in no normal gastric cell. The aim of our present study was to evaluate the distribution of STn in Helicobacter pylori chronic gastritis (HpCG) of pediatric patients. Eighteen gastric biopsies from 15 children (mean age: 11.5 years) with HpCG, 9 gastric biopsies from 9 children without H. pylori infection, and 1 heterotopic gastric mucosa in Meckel's diverticulum were immunostained using the anti-STn antibody STn1 (18/18), NCL-MUC-1 (7/18), and NCL-MUC-2 (18/18) antibodies. Also, sulfated mucosubstances were investigated with the Alcian Blue-Periodic Acid Schiff (AB-PAS), pH 1.0 stain. Although with different intensity (weak in 5/18, moderate 9/18, and intense 4/18) all cases with HpCG exhibited STn immunoreactivity. The expression of STn was found to be located mainly to the supranuclear region of the epithelial cells at the foveolae and glandular necks, with occasional cells showing diffuse cytoplasmic staining. When reactivity was intense, it was for the most part found in the cells at the neck of the glands. The mucus out of the luminal border above the positive cells was usually also stained. MUC-1 was negative (2/7) or weakly positive (5/7) in a few surface mucous cells. MUC-2 was negative (16/18) or occasionally detected in some foveolar and surface cells (2/18). AB-PAS pH 1.0 revealed the presence of sulfomucins in the cytoplasm of isolated cells of gastric pits and glands of most cases (11/15). None of these findings was observed in the control group. We conclude that STn can be identified in gastric cells of pediatric patients with HpCG and that this does not correlate with other mucosubtances markers. Thefindings could indicate that minimal intestinal metaplasia takes place in children with HpCG.  相似文献   
88.
OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age.  相似文献   
89.
Skp2 protein expression in soft tissue sarcomas.   总被引:15,自引:0,他引:15  
BACKGROUND: p45 S phase kinase-associated protein-2 (p45(skp2)), a member of the F-box family of proteins, is an important component of the Skp1-Cullin-F-box protein (SCF) ubiquitin-ligase complex (SCF(skp2)). The latter has been implicated in the ubiquitination and degradation of p27(kip1) (p27) and G(1)-S cell cycle progression. The expression and prognostic role of Skp2 in a large series of soft tissue sarcomas has not been previously investigated. METHODS: Clinicopathologic features and immunohistochemical expression of Skp2, p27, and Ki-67 proteins were studied in 182 cases of soft tissue sarcomas (American Joint Committee on Cancer stages II and III). Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. RESULTS: The male to female ratio was 1.2:1, and the median age at the diagnosis was 53 years. The tumors were predominantly located in the lower extremities (n = 163; 90%) and had a median size of 9 cm. High Skp2 expression (> or = 10% of the cells) was identified in 68 tumors (37%), and was correlated with high grade histology (P =.002) and Ki-67 proliferative index (r = 0.44; P <.0001), but not with p27 expression (r = -0.02; P =.80). By univariate analysis, high Skp2 expression was associated with decreased metastasis-free, disease-free, and overall survival. In a multivariate model, high Skp2 expression was an independent predictor for decreased local recurrence-free, disease-free, and overall survival. CONCLUSION: These results indicate that Skp2 expression is associated with cell proliferation and a worse prognosis in soft tissue sarcomas. The lack of an inverse correlation between Skp2 and p27 suggests that additional molecular events associated with either Skp2 expression or p27 proteolysis may be operating in these tumors.  相似文献   
90.
To assess the role of adjuvant therapy in the treatment of osteogenic sarcoma of the head and neck, treatment and survival information from 173 patients with osteosarcoma of the head and neck was entered into a database. A meta-analysis of the data was attempted with primary emphasis on the effect of adjuvant therapy on disease outcome. The overall 5-year survival was 37%. Patients with mandibular and maxillary tumors had similar survival rates; both groups fared significantly better than patients with extragnathic tumors (P<0.001). Treatment with surgery alone was associated with significantly longer survival rates (P<0.03) than surgery with adjuvant therapy. In the majority of patients reported, information about surgical margins was not available. For this reason, the differences may not adequately represent the effect of adjuvant therapy. While there have been encouraging results with adjuvant treatment protocols for long bone osteosarcoma, the ultimate role of radiation and chemotherapy in the management of osteosarcoma of the head and neck remains unproven. Nevertheless, we recommend that adjuvant therapy be considered due to the poor prognosis in osteosarcoma of the head and neck.  相似文献   
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