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91.
Obscure gastrointestinal bleeding   总被引:9,自引:0,他引:9  
This is one of a series of statements discussing the utilization of GI endoscopy in common clinical situations. The Standards of Practice Committee of the American Society for Gastrointestinal Endoscopy prepared this text. In preparing this guideline, a MEDLINE literature search was performed, and additional references were obtained from the bibliographies of the identified articles and from recommendations of expert consultants. When little or no data exist from well-designed prospective trials, emphasis is given to results from large series and reports from recognized experts. Guidelines for appropriate utilization of endoscopy are based on a critical review of the available data and expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement, and revision may be necessary as new data appear. Clinical consideration may justify a course of action at variance to these recommendations.  相似文献   
92.
The coexistence of both kidney and colon primary malignancies is a rare condition. We report the case of a 75-year-old woman who presented with bilateral pulmonary nodules at chest X-ray and stratigraphy. Total-body CT scan showed multiple, apparently metastatic, bilateral pulmonary lesions, a diffusely dysomogeneous neoformation in the lower pole of the right kidney and a gross neoformation in the ascending colon. A right nephrectomy and a right hemicolectomy were performed and histology showed two primary neoplasms: clear cell renal carcinoma and undifferentiated adenocarcinoma of the colon.  相似文献   
93.
PURPOSE: To determine the role of the two angiogenic peptides, vascular endothelial growth factor (VEGF) and thymidine phosphorylase (TP) (the latter also being a target enzyme for cytotoxicity of 5-fluorouracil and methotrexate), and conventional prognostic factors in predicting relapse-free survival (RFS) and overall survival (OS) probabilities in two cohorts of patients with node-positive breast cancer (NPBC) treated with either adjuvant chemotherapy (CMF [cyclophosphamide, methotrexate, 5-fluorouracil] schedule) or hormone therapy (tamoxifen). PATIENTS AND METHODS: We studied two groups of 137 and 164 patients with NPBC, median follow-up of 72 months for both, treated with adjuvant chemotherapy or hormone therapy, respectively. The cytosolic levels of VEGF and TP were determined in the primary tumor by original immunometric methods. The association between VEGF and TP and of these angiogenic peptides with other prognostic indicators were tested by using the Spearman correlation coefficient (for continuous variables) or the Kolmogorov-Smirnov test (for dichotomous variables). Results of the clinical outcome were analyzed by both univariate and multivariate (for RFS only) Cox regression models in which VEGF and TP were treated as continuous variables. RESULTS: In the CMF group, the concentrations of VEGF and TP ranged from 5.8 to 7798 pg/mg of protein (median, 87.5 pg/mg) and from 1.2 to 904 U/mg (median, 138.2 U/mg), respectively. There was no significant association between the two angiogenic peptides. VEGF was not associated with any other variable, whereas TP showed a positive association with age and an inverse association with the number of involved nodes. In the tamoxifen group, the concentrations of VEGF (5.9-2482; median, 79.3 pg/mg protein) and TP (6.1-1542; median, 146.5 U/mg) were similar to those of the CMF group, and the two angiogenic peptides were not correlated. VEGF was positively associated with age and was inversely associated with estrogen receptor and progesterone receptor, whereas TP was not associated with any other variable. Univariate analysis in the CMF group showed that VEGF and TP were significantly predictive of both RFS and OS. Likewise, the number of involved axillary nodes was significantly associated with both RFS and OS. Univariate analysis in the tamoxifen group showed that TP did not significantly influence either RFS or OS. On the contrary, VEGF levels were significantly predictive of both RFS and OS, as were the number of involved nodes, estrogen receptor concentrations, and progesterone receptor concentration. In the multivariate analysis on RFS in the CMF group, VEGF, TP, their first-order interaction term, and age were significant and independent predictive factors. In the tamoxifen group, only VEGF and the number of involved nodes were significant and independent predictive factors. DISCUSSION: The results of our study suggest that high levels of TP and low levels of VEGF characterize the patients with NPBC treated with adjuvant CMF who have the highest likelihood of favorable outcome. Low levels of VEGF and the presence of less than three involved axillary nodes characterize the patients with NPBC treated with adjuvant tamoxifen who have the highest likelihood of favorable outcome. This information may be useful to plan future studies to better select the patients with NPBC for conventional adjuvant treatments as well as to monitor the efficacy of novel therapeutic strategies of adjuvant therapy based on inhibition of angiogenesis.  相似文献   
94.
Selective block of the femoral and sciatic nerves was performed on 601 patients undergoing knee arthroscopy. The results were good in 87%, adequate in 12%, and poor in 1%. The whole knee surface was covered by the nerve blockade. The duration of anesthesia was 152 ± 21 min and that of analgesia, was 336 ± 18 min. No correlation was observed between the effectiveness of the anesthesia and type of surgery performed. The technique described thus proved adequate for knee arthroscopic surgery, reproducibility was excellent, costs and hospital stays were reduced with respect to general anesthesia, and surgeon and patient satisfaction was high. Received: 25 May 1998  相似文献   
95.
本文用高效液相色谱分离、液闪测定放射性的方法,测定了兔口服炔诺酮肟(NETO)和炔诺酮(NET)的血浓,并比较了二者的药代动力学参数。结果表明:二者吸收迅速,从血中的消除均呈快慢两个时相。NETO在兔体内一部分迅速转变为NET,另一部分则以原药形式存在,24 h内NETO与其代谢产物NET在血清中的浓度大致各占一半。兔口服NETO与NET后,血浓—时间曲线符合二室模型,NETO的达峰时间比NET短,二者有显著差异(P<0.05),其它动力学参数无明显差异(P>0.05)。  相似文献   
96.
The autoradiographic 2-deoxy-D-[1-(-14)C]glucose ([14C]2-DG) method was used to map the effects of subcutaneous (s.c.) morphine (8.0 mg/kg), oxymorphone (0.4 mg/kg) and nalbuphine (16.0 mg/kg) on local cerebral glucose utilization (LCGU), an index of local brain function. At the dosages administered, effects of the opioid agonists on LCGU were very restricted. The mu agonists, injected 15 min before [14C]2-DG, decreased LCGU in thalamic nuclei, including some of those which have been implicated in somatosensory processing, and in the dorsal tegmental nucleus. Nalbuphine did not produce these effects, but stimulated LCGU in nuclei of the spinal tract of the trigeminal nerve and in the globus pallidus. All of the effects on LCGU were blocked by prior administration of naloxone (1.0 or 10.0 mg/kg, s.c., 5 min before morphine or nalbuphine, respectively). Our findings suggest that different supraspinal mechanisms are involved in the actions of mu vs kappa opioids, and indicate that the [14C]2-DG procedure might be helpful in elucidating the anatomical areas involved.  相似文献   
97.
STUDY OBJECTIVE: To evaluate if active cutaneous warming of the two upper limbs with reflex vasoconstriction is less effective in maintaining intraoperative normothermia than warming the vasodilated unoperated lower limb during combined spinal-epidural anesthesia (CSE). DESIGN: Prospective, randomized study. SETTING: Inpatient anesthesia at university departments of orthopedic surgery. PATIENTS: 48 ASA physical status I, II, and III patients, who were scheduled for elective total hip arthroplasty. INTERVENTIONS: Patients received CSE with intrathecal injection of 15 mg of 0.5% hyperbaric bupivacaine. All procedures started 8 to 10 AM, and operating room temperature was maintained between 21 degrees and 23 degrees C, with relative humidity ranging between 40% and 45%. For warming therapy, patients received active forced-air warming of either the two upper limbs (Group Upper body, n = 24), or the unoperated lower limb (Group Lower extremity, n = 24). Core temperature was measured before CSE placement (baseline), and then every 30 minutes until completion of surgery. Time for fulfillment of clinical discharging criteria from the recovery area was evaluated by a blinded observer. MEASUREMENTS AND MAIN RESULTS: Demographic data, duration of surgery, intraoperative blood losses, crystalloid infusion, and hemodynamic variables were similar in the two groups. Core temperature slightly decreased in both groups, but at the end of surgery the mean core temperature was 36.2 degrees +/- 0.5 degree C in Group Upper body and 36.3 +/- 0.5 in Group Lower extremity (NS). At recovery room arrival, seven patients in Group Upper body (29%) and three patients in Group Lower extremity (12.5%) had a core temperature less than 36 degrees C (NS). Shivering was observed in one patient in Group Upper body and in two patients in Group Lower extremity (NS). Clinical discharging criteria were fulfilled after 37 +/- 16 minutes in Group Upper body and 30 +/- 32 minutes in Group Lower extremity (NS). CONCLUSIONS: Forced-air cutaneous warming allows the anesthesiologist to maintain normothermia during CSE for total hip replacement even if the convective blanket is placed on a relatively small skin surface with reflex vasoconstriction. Placing the forced-air warming system on the vasodilated unoperated lower limb may be troublesome to the surgeons and does not offer clinically relevant advantages in warming efficiency.  相似文献   
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100.
High free tryptophan (F-TRP) plasma levels are found in cancer patients (CP). F-TRP plasma concentrations are affected by the levels of its carrier, albumin (ALB), and free fatty acids (FFA) competing with TRP for ALB binding sites. The lack of correlation between F-TRP, ALB and FFA in CP suggests a tumor-dependent effect on the rise in F-TRP. To verify this hypothesis, F-TRP, ALB and FFA levels were assayed in 12 lung and 16 breast CP susceptible to radical surgery, before and 15 days after surgical removal of the tumor. F-TRP levels significantly decreased after tumor ablation. Since no correlation was found between F-TRP, ALB and FFA variations, it is conceivable that the tumor itself may be responsible for the high F-TRP levels in CP.  相似文献   
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