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991.
The wide use of multimodal radiologic analysis of bone tissue has led to a new concept of the term osteopenia towards grouping the various osteopathies as demineralizing osteopathies. With bone densitometry measurements both high precision and accuracy can be achieved, whereas conventional radiographs provide insights into the architecture of the bone to better advantage. By using both modalities discrepancies of the radiological reports with the final diagnosis may be avoided. Despite ongoing success in techniques of semi-automated data analysis and reporting the radiological and the clinical assessment of bone diseases are still an indispensable part of establishing the diagnosis.  相似文献   
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993.
Transvaginal hydrolaparoscopy (THL) is a new culdoscopic technique for exploration of the pelvic cavity that takes advantage of micro-endoscopic technology and uses aquaflotation for inspection of the tubo-ovarian structures. In infertility patients, THL is systematically combined with mini-hysteroscopy, chromopertubation, fimbrioscopy and, when indicated, salpingoscopy. Mini-hysteroscopy in combination with the chromopertubation test allows accurate assessment of the uterine cavity and tubal patency. The transvaginal access combined with the aquaflotation during THL facilitates detailed inspection of the tubo-ovarian structures and detection of subtle pelvic disease. This combined transvaginal endoscopic approach allows complete evaluation of the reproductive tract. THL is better tolerated than hysterosalpingography, less invasive than standard laparoscopy, and can be used safely as a first line investigation of the female partner in a one-stop infertility clinic.  相似文献   
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996.
OBJECTIVES: Antigastric autoantibodies (AGA) can be detected in as many as 50% of adults infected with Helicobacter pylori. We investigated H pylori -associated antigastric autoimmunity in children and adolescents. STUDY DESIGN: Patients with dyspepsia (n = 78; mean age 10.9 years, range 2-21 years, SE 0.46 years) underwent gastroscopy. H pylori infection was determined by serologic and histologic features and breath tests. AGA were detected by immunohistochemistry and were characterized by immunoprecipitation with the gastric hydrogen ion, potassium ion, adenosine triphosphatase (H(+),K(+)-ATPase). In absorption assays, antibodies against H pylori were removed to determine the role of molecular mimicry. RESULTS: AGA were detected in 9 (18%) of the 51 infected patients and in 1 (4 %) of the 27 noninfected patients (P =.08; nonsignificant) and could not be absorbed to H pylori. Children with AGA were significantly older (P =.01). AGA in H pylori gastritis reacted against the gastric H(+),K(+)-ATPase in 3 (33%) of the 9 patients. CONCLUSIONS: The age of the patient or the duration of gastritis seem to be relevant factors for the formation of antigastric autoimmunity. The gastric H(+),K(+)-ATPase represents an autoantigen as early as childhood. No evidence for a role of molecular mimicry between H pylori and the host at this young age could be found.  相似文献   
997.
The purpose of this study was to investigate the fMRI response of the sensorimotor cortex to a vibration paradigm produced by a novel vibrotactile stimulator. Fifteen contiguous slices covering the sensorimotor cortex parallel to the anterior (AC) and posterior commissure (PC) line were obtained with echoplanar magnetic resonance imaging at 1.5T. Cortical activity in ten healthy subjects (20-45 years) was investigated during vibration (50 Hz) of the palm of the right hand and compared to a finger-to-thumb tapping paradigm. For the vibration paradigm a mechanically driven vibration head was mounted on the palm of the right hand. The new vibration device produces vibration frequencies (1-130 Hz) and displacement amplitudes (0.5-4 mm) suitable to elicit the tonic vibratory reflex. The fMRI measurement during vibratory stimulation revealed activation in the pre- and postcentral gyrus in all subjects. These activations were comparable to the finger-to-thumb tapping paradigm. The advantages of the new MR compatible vibration device include effective transmission of the stimulus and controlled vibration frequencies and intensities. These preliminary fMRI results indicate that vibration can be an alternative paradigm for the evaluation of sensory and motor functions in patients unable to perform active motor paradigms.  相似文献   
998.
Study objective: To determine if measuring skin tissue thickness by a recently developed 10 MHz ultrasound scan may be used as a valuable parameter to guide fluid therapy and detect fluid shifts to the extravascular space during surgical procedures in addition to central venous pressure (CVP). Study design: Prospective, clinical and observational study. Setting: An operation theatre of the Ear Nose Throat (ENT) department of an university hospital. Patients: Following approval by the local ethics committee 12 otherwise healthy male patients undergoing ENT surgery for oropharyngeal carcinoma were involved in this study. The patients stayed nil per os for 10 h before induction of anaesthesia. Interventions/measurements: Crystalline fluids (Ringer's solution) were supplied at a constant rate of 10 ml kg–1 bw h–1. Patients were kept in the supine position during surgery, no further interventions were performed. Additional to routine monitoring, tissue thickness (TT) of proximal pre‐tibial skin and CVP were measured every 30 min, haematocrit was determined hourly for 5 h starting at t0. Main results: Haematocrit constantly declined during the observation period, showing a significant difference in t0 after 120 min. The increase in TT was strongly correlated with intraoperative positive fluid balance (r=0·96), while the course of CVP did not reflect the amount of fluid application comparably. Conclusions: Non‐invasive determinations of skin tissue thickness by the presented ultrasonic device appears to give additional information on fluid intake and distribution during clinical anaesthesia.  相似文献   
999.
Idiopathic myelofibrosis (IMF) is a breakpoint cluster region rearrangement-negative chronic myeloproliferative disease with progressive bone marrow fibrosis. We report a female patient (65 years old) who was admitted to our hospital in 1996. Trephine bone marrow biopsy revealed diffuse fibrosis with atypical multilobulated megakaryocytes. A cellular phase of IMF was diagnosed. Three years later, despite being at intermediate risk, the patient developed generalized lymphadenopathy and multiple sclerosing tumors throughout the peritoneum and retroperitoneum. Biopsy specimens from these tumors revealed sclerosing hematopoietic infiltrates. The present case demonstrates that IMF not only can progress to acute leukemia but can also spread uncontrollably, or 'metastasize' with extensive sclerosing hematopoietic tumors throughout the body.  相似文献   
1000.
BACKGROUND: The administration of radiographic contrast agents remains an important cause of acute renal failure. The optimal infusion for hydration has not been evaluated. OBJECTIVE: To compare the incidence of contrast media-associated nephrotoxicity with isotonic or half-isotonic hydration. DESIGN: Prospective, randomized, controlled, open-label study. METHODS: Patients scheduled for elective or emergency coronary angioplasty were randomly assigned to receive isotonic (0.9% saline) or half-isotonic (0.45% sodium chloride plus 5% glucose) hydration beginning the morning of the procedure for elective interventions and immediately before emergency interventions. An increase in serum creatinine of at least 0.5 mg/dL (44 micromol/L) within 48 hours was defined as contrast media-associated nephrotoxicity. Secondary end points were cardiac and peripheral vascular complications. RESULTS: A total of 1620 patients were assigned to receive isotonic (n = 809) or half-isotonic (n = 811) hydration. Primary end point analysis was possible in 1383 patients. Baseline characteristics were well matched. Contrast media-associated nephropathy was significantly reduced with isotonic (0.7%, 95% confidence interval, 0.1%-1.4%) vs half-isotonic (2.0%, 95% confidence interval, 1.0%-3.1%) hydration (P =.04). Three predefined subgroups benefited in particular from isotonic hydration: women, persons with diabetes, and patients receiving 250 mL or more of contrast. The incidence of cardiac (isotonic, 5.3% vs half-isotonic, 6.4%; P =.59) and peripheral vascular (isotonic, 1.6% vs half-isotonic, 1.5%, P =.93) complications was similar between the 2 hydration groups. CONCLUSION: Isotonic hydration is superior to half-isotonic hydration in the prevention of contrast media-associated nephropathy.  相似文献   
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