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991.
Mitral leaflet motion during systole was studied by echocardiography in 102 healthy young men. Mean posterior maximal leaflet motion was 2 +/- 1 mm behind the CD line on 2-dimensionally (2-D) directed M-mode examination. On the apical 4-chamber cross-sectional view a mean area of 0.34 +/- 0.24 mm2 was contained by the mitral leaflets above the plane of the mitral anulus. Elevated values on the M-mode view (greater than or equal to 4 mm) compared with the 2-D 4-chamber view (greater than or equal to 0.70 mm2) were discordant, with 90% (18 of 20) of the elevated values found in 1 view only. Thus, there is a wide spectrum of mitral leaflet motion in asymptomatic young men. The value of the echocardiogram in diagnosis of mitral valve prolapse is questionable because any cutoff point between normal and abnormal is arbitrary and the degree of motion has not been shown to correlate with morbidity or mortality.  相似文献   
992.
To determine whether patients with systemic lupus erythematosus undergoing long-term peritoneal dialysis have persistent clinical and serologic remissions, the clinical courses of eight patients with end-stage renal disease in whom peritoneal dialysis was begun at Rush-Presbyterian-St. Luke's Medical Center between 1981 and 1986 were analyzed. Patients were followed for a mean of 90.1 +/- 28.8 months before dialysis and 20.8 +/- 4.7 months after the initiation of dialysis. Disease activity was quantified for each individual in terms of "flares" per year before and after the initiation of peritoneal dialysis, the means of which were 0.66 +/- 0.46 and 0.94 +/- 0.28, respectively. Comparison of these rates showed no statistical difference. Seven of the eight patients had at least one flare while receiving peritoneal dialysis, all of which required prednisone therapy (mean 31.3 mg per day). The clinical manifestations included fever, rash, myalgias, anemia, leukopenia, serositis, and cerebritis. Eighty-eight percent of these flares had associated worsening of serologic results. Prednisone was discontinued in only one patient at any time during peritoneal dialysis. This experience reveals that patients with lupus continue to show clinical and serologic disease activity and require maintenance prednisone therapy while receiving long-term peritoneal dialysis.  相似文献   
993.
Hypophosphatemia has been shown to cause acute respiratory failure. The mechanism is believed to be due to decreased high-energy substrate availability at the cellular level leading to respiratory muscle dysfunction. However, direct measurement of these substrates has not been previously studied. A patient with hypophosphatemic respiratory failure is described in whom phosphocreatine and pH were continuously monitored using nuclear magnetic resonance spectroscopy. This revealed a defect in muscle metabolism that required several weeks to recover despite prompt correction of the serum phosphate level.  相似文献   
994.
995.
We have introduced a targeted mutation in SH2D1A/DSHP/SAP, the gene responsible for the human genetic disorder X-linked lymphoproliferative disease (XLP). SLAM-associated protein (SAP)-deficient mice had normal lymphocyte development, but on challenge with infectious agents, recapitulated features of XLP. Infection of SAP- mice with lymphocyte choriomeningitis virus (LCMV) or Toxoplasma gondii was associated with increased T cell activation and IFN-gamma production, as well as a reduction of Ig-secreting cells. Anti-CD3-stimulated splenocytes from uninfected SAP- mice produced increased IFN-gamma and decreased IL-4, findings supported by decreased serum IgE levels in vivo. The Th1 skewing of these animals suggests that cytokine misregulation may contribute to phenotypes associated with mutation of SH2D1A/SAP.  相似文献   
996.
OBJECTIVE: To evaluate the efficacy of routine follow-up in patients with recurrent uterine cancer. METHODS: In a single institution study, a total of 2637 patients were treated curatively for uterine cancer from 1990 to 2006. A total of 438 patients experienced disease recurrence. Data for detailed analysis were available from 280 of the 438 patients. Prior to the diagnosis of recurrence, all patients had regular follow-up and were investigated through internal examination, vaginal vault cytology and imaging. Overall survival (OS) was the main study endpoint and was calculated from recurrence diagnosis to death or date censored. RESULTS: Clinical and histopathological features as well as patterns of recurrence were similar in symptomatic and asymptomatic patients. Eighty-one patients (28.9%) were diagnosed with asymptomatic recurrence while 199 patients (71.1%) presented with symptomatic recurrence. The overall survival probability at 5 years was 41.0% and 28.9% respectively for asymptomatic and symptomatic patients (log-rank p=0.013). Those patients with stage 1 or 2 tumors of endometrioid type were found to have an overall survival probability at 5 years of 38.0% and 25.7% respectively for asymptomatic and symptomatic recurrence (log-rank p=0.05). The absence of symptoms did not impact on the outcome of patients with stage 3 tumors or tumors of non-endometrioid type. CONCLUSIONS: While patients at low/intermediate risk of recurrence may benefit from intensive follow-up including internal examinations, routine vaginal vault cytology and imaging, high-risk patients might gain more from an alternate follow-up strategy with emphasis on imaging in conjunction with symptom education.  相似文献   
997.
OBJECTIVE: To evaluate the prognostic value of an amniotic fluid index (AFI) < or = 5 cm for an adverse perinatal outcome in pregnancies with the syndrome of hemolysis, elevated liver enzymes and low platelets (HELLP syndrome). STUDY DESIGN: A prospective, observational study of patients with the HELLP syndrome. An ultrasound estimate of amniotic fluid volume was obtained on admission. Adverse intrapartum outcomes included amnioinfusion for variable decelerations and/or indicated abdominal/vaginal operative delivery for nonreassuring fetal heart rate changes. Maternal characteristics and perinatal outcome parameters were compared AFI < or = vs. > 5 cm. Statistical analysis was performed using chi2 analysis, Student's t test and receiver-operator characteristic curve (ROC) analysis. RESULTS: Between January 1996 and February 1999, 120 patients were enrolled. Twenty-six (22%) had an AFI < or = 5 cm. This group did not differ from that with AFI > 5 cm regarding the severity of the HELLP syndrome, admission-to-delivery interval (p = 0.354), variable decelerations in labor (p = 0.06), Apgar score of < 7 at 5 minutes (p = 0.361), cesarean delivery for nonreassuring fetal status (p = 1.0) or significant fetal acidosis (pH < 7.0 [p = 0.2101). ROC analysis revealed no AFI measurement between 0 and 16 cm that was useful for identifying the compromised fetus. CONCLUSION: Antepartum/intrapartum performance of AFI in patients with the HELLP syndrome is a poor prognostic test for subsequent fetal compromise.  相似文献   
998.
BACKGROUND: Since the introduction of the Pap smear screening, the incidence of squamous cell carcinoma (SCC) has decreased significantly, but the incidence of adenocarcinoma (AC) relative to SCC has increased. AIM: To compare the Pap smear history of patients with AC and SCC of the cervix. METHODS: Patients for the study were identified from the database of Queensland Centre for Gynaecological Cancer. Patients with AC and SCC were matched for age at diagnosis and International Federation of Gynecology and Obstetrics stage. The final population included 188 matched pairs, being 376 patients in total. Data were collected upon the histological type of cancer, result of the most recent Pap smear, date and result of the Pap smear prior to the most recent Pap smear and symptoms. Chi-squared tests and Fisher's exact test were used to compare the two patient groups for several variables. RESULTS: Patients with AC had significantly more false-negative results on their most recent Pap smear (P<0.0001) than patients with SCC. The incidence of symptoms such as bleeding and/or vaginal discharge was comparable in patients with AC and SCC. The time between the most recent Pap smear and the diagnosis of cervical cancer was significantly shorter for patients with AC (P=0.01). CONCLUSIONS: Patients with AC had Pap smears more regularly than those with SCC, and their most recent Pap smear was significantly more likely to be normal. Thus, Pap smear prior to a diagnosis of AC is more likely than SCC false-negative and therefore not indicative of cervical cancer.  相似文献   
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