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121.
The aim of this study was to examine whether maternal serum uric acid (UA) concentrations are influenced by the number of fetuses and whether this effect is confounded by maternal body mass index (BMI). Medical records of 207 consecutive twin and 69 triplet pregnancies admitted to our high-risk pregnancy unit between 1994 and 1998 were reviewed. Pregnancies complicated by acute or chronic renal diseases, vascular diseases, hypertension, hemolysis, diabetes mellitus, or proteinuria were excluded. The remaining 137 twin and 42 triplet pregnancies were matched with 118 consecutive singleton pregnancies who met the same exclusion criteria and were admitted in the first half of 1998. Each birth order study group was further stratified and compared within three maternal BMI subgroups. Serum UA concentrations were higher in twin and triplet pregnancies compared to singletons (4.6 +/- 1.3, 5.2 +/- 1.2, and 3.8 +/- 0.7 mg%, respectively; p <0.01). These differences in UA concentration persisted after grouping by BMI classes. Serum UA concentration in pregnancy are positively correlated with the number of fetuses. For clinical purpose, the UA cutoff concentration should be adjusted using mean + 2 SD as follows: 5.2, 7.2, and 7.6 for singleton, twin, and triplets, respectively.  相似文献   
122.
OBJECTIVE: To identify the risk factors for preterm birth in primigravidae with twin gestation and the role of transvaginal ultrasonographic assessment of the cervix. METHODS: Between January 1996 and December 1996, 54 twin pregnancies were prospectively enrolled. All women were at their first pregnancy. All women conceived following infertility treatments and all had a normal uterine cavity proven by hysterosalpingography (HSG) or hysteroscopy. Multiple logistic regression analysis was used to evaluate the association between the length of the cervix at 18-24 weeks of gestation and outcome variables, controlling for possible confounding factors. RESULTS: The mean +/- SD maternal age was 30.9 +/- 5.3 years (range 22-46), and five of them were aged 40 or more. Nine patients (20.5%) delivered prematurely, defined as spontaneous delivery at or before 34 weeks of gestation. There was no statistically significant difference between women who delivered before or after 34 weeks of gestation in regard to maternal age, body mass index (BMI), weight gain in pregnancy, smoking and work during pregnancy. The mean cervical length of patients who delivered before 34 weeks of gestation (30.1 +/- 6.1 mm) was significantly shorter than that of women who delivered after 34 weeks of gestation (42.2 +/- 6.2 mm; P < 0.001). Cervical length longer than 35 mm predicted delivery after 34 weeks of gestation with sensitivity and specificity of 88.5% and 88.9%, respectively. The positive and negative predictive values were 96.9% and 66.7%. CONCLUSION: A transvaginal ultrasonographic measurement of the cervix > 35 mm at 18-24 weeks in twin gestation can identify patients at low risk for delivery before 34 weeks. Maternal age, BMI, weights gain, smoking and work during the pregnancy did not influence the duration of the pregnancy.  相似文献   
123.
In vitro fertilization is a risk factor for vasa previa   总被引:2,自引:0,他引:2  
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124.
BACKGROUND: We have previously suggested that helminthic infections make the host more susceptible to HIV infection and enhance its progression due to the chronic immune activation they cause. OBJECTIVE: To study the effect of antihelminthic treatment on HIV plasma viral load (VL) in HIV- and helminth-infected individuals living in Ethiopia. METHODS: Fifty-six clinically asymptomatic HIV-1-infected individuals, 31 (55%) of whom were also infected with helminths, were studied. All participants received antihelminthic treatment at baseline and at 3 and 6 months. Worm egg excretion, HIV plasma VL, and T-cell subsets were determined at baseline and 6 months after treatment. RESULTS: The mean age, number of CD4 T cells, and gender distribution were similar in the helminth-infected and -noninfected groups. At baseline, HIV plasma VL was strongly correlated to the number of eggs excreted (p <.001) and was higher in individuals infected with more than one helminth (5.28 +/- 0.35 versus 4.30 +/- 1.13 log RNA copies/mL, respectively; p =.16). After treatment of helminths, the 6-month change in HIV plasma VL was significantly different between the successfully treated group and the persistently helminth-positive group (p =.04) CONCLUSIONS: Helminth "load" is correlated to HIV plasma VL, and successful deworming is associated with a significant decrease in HIV plasma VL. The results of the current study, if confirmed in a larger study, may have important implications for slowing disease progression and reducing risks of transmission.  相似文献   
125.
OBJECTIVES: This study sought to characterize the relationship of conduction delays detected by pace-mapping, evident as a stimulus to QRS interval (S-QRS) delay >or=40 ms, to ventricular tachycardia (VT) re-entry circuit isthmuses defined by entrainment and ablation. BACKGROUND: Areas of slow conduction and block in old infarcts cause re-entrant VT. METHODS: In 12 patients with VT after infarction, pace-mapping was performed at 890 sites. Stimulus to QRS intervals were measured and plotted in three-dimensional reconstructions of the left ventricle. Conduction delay was defined as >or=40 ms and marked delay as >80 ms. The locations of conduction delays were compared to the locations of 14 target areas, defined as the region within a radius of 2 cm of a re-entry circuit isthmus. RESULTS: Pacing captured at 829 sites; 465 (56%) had no S-QRS delay, 364 (44%) had a delay >or=40 ms, and 127 (15%) had a delay >80 ms. Sites with delays were clustered in 14 discrete regions, 13 of which overlapped target regions. Only 1 of the 14 target regions was not related to an area of S-QRS delay. Sites with marked delays >80 ms were more often in the target (52%) than sites with delays 40 to 80 ms (29%) (p < 0.0001). CONCLUSIONS: Identification of abnormal conduction during pace-mapping can be used to focus mapping during induced VT to a discrete region of the infarct. Further study is warranted to determine if targeting regions of conduction delay may allow ablation of VT during stable sinus rhythm without mapping during VT.  相似文献   
126.
Rat stromal bone-marrow cells cultured in the presence of dexamethasone, ascorbic acid, beta-glycerophosphate, and fibroblast growth factor-2 (FGF-2) express the osteogenic phenotype (Pitaru et al., J. Bone Miner. Res. 8:919-929, 1993). The purpose of this study was to establish a long-term homogeneous culture expressing the osteogenic phenotype. The cultures were routinely passaged every 5 days in the absence or presence of either or both dexamethasone and FGF-2, and the cumulative doubling number and the expression of the osteogenic phenotype were determined. Cultures treated with dexamethasone (10(-7) M) ceased proliferation and only upon addition of FGF-2 (3 ng/ml) was a spontaneous immortalization achieved, as expressed by sustained proliferation for about 1 year, with a doubling time of 22 h and more than 300 doublings in 72 passages. Both FGF-2 and dexamethasone are required and act synergistically to maintain cell propagation, alkaline phosphatase expression, and osteocalcin secretion; however, protein content was FGF-2 dependent and the mineralization was dexamethasone dependent. Repetitive single-cell cloning tested the homogeneity and stability of the cells expressing the osteogenic phenotype in these long-term cultures. It was shown that 25% to 50% of subclones derived from clones with an osteogenic phenotype do not further express the osteogenic phenotype. In conclusion, we have established a spontaneously immortalized dexamethasone- and FGF-2-dependent rat stromal bone-marrow-derived long-term culture expressing the osteogenic phenotype. The cultures tend to lose the osteogenic phenotype, and dexamethasone supports the long-term preservation of the osteogenic phenotype.  相似文献   
127.
A case of a 9-year-old child with hereditary gingival fibromatosis, supernumerary tooth, chest deformities, auricular cartilage deformation, joint laxity and undescended testes is described. The exact mode of inheritance is unclear; a new mutation pattern is possible. These features resemble but differ from the previously reported Laband syndrome. The dental treatment consisted of surgical removal of the fibrous tissue and conservative restorative treatment under general anesthesia. The dental practitioner should be alert for developmental abnormalities such as supernumerary teeth and delayed tooth eruption. A comprehensive medical history and physical systemic evaluation is essential to rule out other systemic abnormalities. Genetic consultation is mandatory for future family planing.  相似文献   
128.
Long-term mental health of men after a first acute myocardial infarction   总被引:2,自引:0,他引:2  
OBJECTIVE: To evaluate the differential and independent impact of sociodemographic, medical, and psychologic variables assessed at hospital discharge on patients' short- and long-term mental health. DESIGN: Longitudinal study. SETTING: Eight medical centers in central Israel. PARTICIPANTS: Male Israeli patients (N = 209; age range: 30-65 y) with documented first acute myocardial infarction (AMI). INTERVENTION: Subjects were interviewed 3 times, once (T1) before hospital discharge, a second time (T2) at 3 to 6 months after discharge, and a third time (T3) at 5 years post-AMI. Sociodemographic, medical, and psychologic data were elicited at the first interview and completed with medical information in the files. Psychologic well-being and psychologic distress were evaluated by the Mental Health Inventory at the second and third interviews. These 2 outcome variables were compared with normative community data on these aspects of mental health. MAIN OUTCOME MEASURES: Hierarchical regression was used to examine the relation between the independent variables, sociodemographic, medical, and psychologic variables, and the dependent variables, psychologic well-being and psychologic distress, at T2 and T3. RESULTS: Depression, perceived health, sense of coherence, social support, and educational level at discharge predicted aspects of mental health 3 to 6 months and 5 years post-AMI. However, only psychologic distress differentiated between the research participants and the normative community sample of men. CONCLUSIONS: A first episode of AMI appears to increase psychologic distress more than it decreases psychologic well-being both 3 to 6 months and 5 years post-AMI. Educational level and sense of coherence may serve as protective factors, whereas depression may foster vulnerability to distress and impaired psychologic well-being.  相似文献   
129.
130.
OBJECT: The goal of this paper was to investigate a possible relationship between the consumption of low-dose aspirin (LDA) and traumatic intracranial hemorrhage in an attempt to determine whether older patients receiving prophylactic LDA require special treatment following an incidence of mild-to-moderate head trauma. METHODS: Two hundred thirty-one patients older than 60 years of age, who arrived at the emergency department with a mild or moderate head injury (Glasgow Coma Scale [GCS] Scores 13-15 and 9-12, respectively), were included in the study. One hundred ten patients were receiving prophylactic LDA (100 mg/day) and these formed the aspirin-treated group. One hundred twenty-one patients were receiving no aspirin, and these formed the control group. There was no statistically significant difference between the two groups with respect to age, sex, mechanism of trauma, or GCS score on arrival at the emergency department. Most of the patients sustained the head injury from falls (88.2% of patients in the aspirin-treated group and 85.1% of patients in the control group), and had external signs of head trauma such as bruising or scalp laceration (80.9% of patients in the aspirin-treated group and 86.8% of patients in the control group). All patients underwent similar neurological examinations and computerized tomography (CT) scanning of the head. The CT scans revealed evidence of traumatic intracranial hemorrhage in 27 (24.5%) patients in the aspirin-treated group and in 31 patients (25.6%) in the control group. Surgical intervention was required for five patients in each group (4.5% of patients in the aspirin-treated group and 4.1% of patients in the control group). A surprising number of the patients who arrived with GCS Score 15 were found to have traumatic intracranial hemorrhage, as revealed by CT scanning (11.5% of patients in the aspirin-treated group and 16.5% of patients in the control group). Surgery, however, was not necessary for any of these patients. CONCLUSIONS: There was no statistically significant difference in the frequency or types of traumatic intracranial hemorrhage between patients who had received aspirin prophylaxis and those who had not. The authors conclude that LDA does not increase surgically relevant parenchymal or meningeal bleeding following moderate and minor head injury in patients older than 60 years of age.  相似文献   
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