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111.
OBJECTIVE: Microalbuminuria (MA) is a marker of adverse outcome in hypertension. The aim of this study was to investigate the association of MA with cardiovascular risk factors and glomerular hyperfiltration in the early stage of hypertension and to assess its predictive value for the development of sustained hypertension requiring antihypertensive treatment. DESIGN AND PARTICIPANTS: We studied 1041 young stage 1 hypertensive subjects. Study variables were 24-h ambulatory blood pressure and heart rate, anthropometric measures, metabolic variables, creatinine clearance and lifestyle factors analyzed as a function of ascending urinary albumin measured from 24-h collections. Subjects were followed until they developed sustained hypertension and were eligible for antihypertensive medication according to current guidelines. SETTING: Seventeen outpatient clinics in Italy. RESULTS: Eighty-five percent of the subjects were normoalbuminuric, 9% had borderline MA, and 6% had overt MA. No between-group differences were found for age, body mass index, heart rate, lifestyle factors and biochemistry in both genders. Creatinine clearance was greater in the subjects with overt MA and borderline MA than in the normoalbuminuric subjects (P = 0.003 and 0.011, respectively). In a two-way ANCOVA, microalbuminuric subjects both with hyperfiltration (P < 0.001) and with normal filtration (P = 0.04) had higher 24-h systolic blood pressure than subjects with normoalbuminuria and normal filtration. In a Cox analysis, neither MA nor hyperfiltration were significant predictors of development of sustained hypertension. CONCLUSION: MA is not associated with an adverse metabolic risk profile in the early stage of hypertension. MA is associated with greater hemodynamic load and with glomerular hyperfiltration in this clinical setting, but does not help in predicting those subjects destined to develop sustained hypertension requiring antihypertensive therapy.  相似文献   
112.
Severe, medically unresponsive pulmonary hypertension (PHT) is considered to be a contraindication for orthotopic heart transplantation (OHT). Chronic left ventricular (LV) unloading using a left ventricular assist device (LVAD) might result in reversal of the elevated pulmonary vascular resistance (PVR), allowing successful OHT in such patients. In this study, we present a patient with end-stage ischemic cardiomyopathy and fixed, elevated PVR (7.1 Wood units) who underwent implantation of a Novacor LVAD (Baxter Healthcare Corp., Deerfield, IL, U.S.A.), with a subsequent reduction in PVR to 1.2 Wood units and successful OHT eleven months post-LVAD implantation. Three years after heart transplant, the patient still leads an active life with no right heart failure. In conclusion, OHT is not contraindicated in patients with end-stage heart failure and medically unresponsive PHT in the presence of elevated left atrial pressure. Left ventricular unloading should be considered in these patients to allow reversal of the elevated PVR before OHT.  相似文献   
113.
The purpose of this study was to obtain comparative data concerning the relative contribution of segmental cervical vertebral motion to the cervical range of motion (ROM) in whiplash and healthy subjects in an effort to evaluate the usefulness of X-ray analysis in future forensic and research efforts. Each subjects neck ROM was measured with an optoelectronic system and also by X-ray measurements of the angular rotation in flexion and extension. The X-rays were examined to calculate the angular movement in the sagittal plane of each of the functional units C2–C3 to C6–C7. The chronic whiplash subjects showed reduced total neck range in all directions as compared to healthy subjects (p<0.001). There was a reduced total angular rotation from flexion to extension between these two groups (p<0.01), but no significant difference, however, between chronic whiplash subjects and controls in the percentage contribution of each of the functional units C2–C3 to C6–C7 to this rotation. This data will now allow a design of trials where healthy subjects are asked to simulate restricted neck ROM while undergoing optokinetic and X-ray evaluation of segmental vertebral motion. We will be able to determine if simulators produce a similar pattern to chronic whiplash and healthy, non-simulating subjects, and thus determine if, at least for forensic and research purposes, this technique is useful in validating reported restricted neck range.  相似文献   
114.
The authors evaluated the efficacy of antithymocyte globulin (ATG) induction and delayed initiation of cyclosporine (CsA) in heart transplant (HTx) patients with postoperative renal dysfunction (RD). The authors compared 15 adult HTx patients with postoperative RD (serum creatinine [SCr] > or =150 microM) to 17 controls without postoperative RD. ATG was given daily (1.5 mg/kg/day for 5 days) in controls and every 2 to 5 days in RD patients (total lymphocyte count <200/mm). All patients received corticosteroids and mycophenolate mofetil. The initiation of CsA was delayed in RD patients until SCr had decreased to less than 150 microM (day 12 +/- 8 vs. 2 +/- 1, P<0.0001). One-year patient survival and acute rejection rates were 87% and 27% in RD patients and 88% and 59% in controls, respectively (P=not significant). SCr improved in RD patients and did not differ from controls after the first month. The authors' results suggest that marked prolongation of the period of ATG induction permits a safe delay in the initiation of CsA in HTx patients with postoperative RD.  相似文献   
115.
There is a very limited published material about experience with long-term pediatric mechanical circulatory support as a bridge to heart transplant. We report on a 2-year-old, 12 kg boy admitted with 2-week history of low-grade fever, ear pain, pulmonary edema, and congestive heart failure. Trans-thoracic echocardiography confirmed severe myocardial dysfunction with a left ventricular ejection fraction of 0.20 and percentage shortening of 13. After 2 days of ventilatory and inotropic support, the patient continued to deteriorate and subsequently required femoro-femoral extracorporeal life support (ECLS). This was later complicated by a progressive coagulopathy and massive bleeding. On day 17, a pulsatile pediatric paracorporeal biventricular assist device (VAD) (Berlin Heart) was implanted. The patient's condition improved significantly with all coagulopathies corrected, and the patient was extubated 21 days later. After 109 days of bi-VAD support, the patient was successfully transplanted and discharged home 45 days post transplant. Our early experience with initial ECLS bridge to VAD and subsequently to transplant was encouraging. It allowed for additional time to select the ideal organ donor and optimize the recipient's comorbid condition and multiorgan failure. VAD provides an additional armamentarium of circulatory support in pediatric patients with severe heart failure.  相似文献   
116.
PURPOSE: We investigated if an adequate histological diagnosis can be made from tissue after holmium laser enucleation of the prostate (HoLEP) and whether it is comparable to transurethral prostate resection (TURP) tissue findings in patients with benign prostatic hyperplasia. MATERIALS AND METHODS: We analyzed 40 HoLEP and 40 age matched TURP tissue specimens from patients who underwent 1 of the 2 procedures between January 2001 and August 2002. Each histological specimen was reviewed by a single pathologist. Preoperative prostate ultrasound volume, total serum prostatic specific antigen and postoperative tissue weight were evaluated. Microscopic histological diagnosis was assessed by standard histological techniques and immunohistochemical evaluation. RESULTS: Patients were comparable in terms of age and preoperative total serum prostate specific antigen. Tissue remaining following the procedure was estimated to be 36.3% of preoperative ultrasound volume after HoLEP and 52.8% after TURP (p <0.001). Incidental adenocarcinoma and high grade PIN of the prostate were diagnosed in a comparable percent of specimens in the 2 groups. Tissue thermal artifacts induced by the laser were mostly due to coagulation. Thus, the alterations were similar to those after TURP. CONCLUSIONS: Tissue quality is altered after HoLEP and TURP. General prostatic architecture was maintained in the majority of HoLEP histological specimens. A moderately higher percent of prostatic tissue obtained by the Ho laser is lost by vaporization and coagulation. Nevertheless, these differences do not seem to alter pathologist ability to detect incidental prostate cancer and PIN.  相似文献   
117.
We have described the 17th century dispute on the nature of the poison of the viper and its possible use as an antidote which arose between published in Britain at that time. We have also seen the reciprocal interest of Charas and members of the Royal Society in each other's work, and how Charas settled in England for a few years at the time of discrimination against the Huguenots in France. We prefer to leave any conclusions from this story to individual readers. However the dispute seems to be part of a transition from an animate view of the world to one where empirical methods do not appear to need to invoke 'spirits'. The story also seems to illustrate the limitation of experiments there can still be disagreement. If there is a the feeling that the subject is of interest, we can broaden it to cover scientific exchanges and connections between British and French Scholars in the field of pharmaceutical chemistry in the 17th and 18th centuries. At that time a number of pharmacists and scientists moved or corresponded between the two countries influencing one another. That was when modern chemistry gradually evolved out of traditional origins.  相似文献   
118.
BACKGROUND: Flow cytometry (FC) is a useful adjunct to fine-needle aspiration cytology (FNC) in evaluating lymphoproliferative disorders. The authors present a critical review of 307 lymph nodal and extra lymph nodal lymphoproliferative disorders that were diagnosed with FNC and FC. METHODS: FC was performed over a 4-year period on 185 palpable and 122 impalpable lymph nodal and extra lymph nodal lymphoproliferative processes under ultrasound or computed tomography guidance. FC was performed using the following fluoresceinated antibodies: CD3, CD4/CD8, CD2/CD7/CD3, CD5/CD10/CD19, CD19/kappa/lambda, FMC7/CD23/CD19, CD38/CD56/CD19, and bcl-2. The series included 15 inadequate, 10 suspicious, and 135 benign reactive hyperplasias (BRHs); 70 primary non-Hodgkin lymphomas (NHLs), and 77 recurrent NHLs (rNHLs). FC/FNC diagnoses of suspicious, NHL, and rNHL were controlled either histologically or clinically or by the interphase fluorescence in situ hybridization demonstration of t(11;14)(q13;q32) in two cases of mantle cell lymphoma. BRHs were controlled by follow-up. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the FC/FNC diagnoses of NHL, rNHL, and BRH were calculated as well as the identification of specific subtypes among the small- and medium-sized cells. RESULTS: Statistical analysis showed 93% sensitivity, 100% specificity, 100% PPV, and 91% NPV in NHL, rNHL, and BRH discrimination. The subclassification of small cell and medium-sized NHLs showed 63% sensitivity, 88% specificity, 95% PPV, and 37% NPV. CONCLUSIONS: FC applied to FNC enhanced the precision of cytologic diagnosis in lymph nodal and extra lymph nodal lymphoproliferative disorders and allowed further subclassification in more than half of the cases, thus avoiding invasive surgical biopsies in many patients.  相似文献   
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