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81.
Objective To determine whether increasing maternal age increases the risk of operative delivery and to investigate whether such a trend is due to fetal or maternal factors.
Design Analysis of prospectively collected data on a maternity unit database.
Setting A postgraduate teaching hospital.
Population 6410 nulliparous women with singleton cephalic pregnancies delivering at term (37–42) weeks of gestation) between 1 January 92 and 31 December 95.
Main outcome measures Mode of delivery, rates of prelabour caesarean section, induction of labour and epidural usage.
Results There was a positive, highly significant association between increasing maternal age and obstetric intervention. Prelabour (  P < 0.001  ) and emergency (   P < 0.001  ) caesarean section, instrumental vaginal delivery (spontaneous labour   P < 0.001  ; induced labour   P = 0.001  ), induction of labour (   P < 0.001  ) and epidural usage in spontaneous labour (  P = 0.005  ) all increased with increasing age. In the second stage of labour fetal distress and failure to advance, requiring instrumental delivery, were both more likely with increasing maternal age (in both   P < 0.001  ). Epidural usage in induced labour and the incidence of small for gestational age newborns did not increase with increasing maternal age (P = 0.68 and  P = 0.50  , respectively).
Conclusions This study demonstrates that increasing maternal age is associated with an incremental increase in obstetric intervention. Previous studies have demonstrated a significant effect in women older than 35 years of age, but these data show changes on a continuum from teenage years. This finding may reflect a progressive, age-related deterioration in myometrial function.  相似文献   
82.
Zusammenfassung Die bakterielle Meningitis stellt trotz großer Fortschritte in Diagnostik, intensivmedizinischer Betreuung und antibiotischer Behandlungsmöglichkeiten noch immer eine ernst zu nehmende, oft lebensbedrohliche Erkrankung des Kindesalters dar. Sie hinterlässt bei einer hohen Zahl der Überlebenden bleibende neurologische und neuropsychologische Defizite. Sowohl für die Verbesserung derzeitiger Strategien als auch für die Entwicklung neuer Optionen in Diagnostik, Prävention und Therapie sind die Kenntnis und das Verständnis der Pathogenese und Pathophysiologie von Meningitiden äußerst wichtig.  相似文献   
83.
84.
BACKGROUND: We examined the lateralizing value of postictal language and motor deficits and studied their underlying mechanisms. PATIENTS AND METHODS: The total sample consisted of 35 patients (26 temporals, 8 frontals, 1 parietal) with a good postsurgical outcome (Engel's class I and II). Postictal examination was blindly reviewed on videotapes. In 15 cases (29 seizures), postictal language manifestations were analyzed in relation with the diffusion of the epileptic discharge recorded by intracerebral EEG. Language dominance was determined by the intracarotid amobarbital test. RESULTS: Postictal aphasia was observed only when (1) seizure originated in the dominant hemisphere and (2) ictal activity spread to language areas (Wernicke and/or Broca areas). When the epileptic focus was in the nondominant hemisphere, no postictal aphasia was observed even if there was secondary generalization of ictal activity affecting the language areas of the dominant hemisphere. Postictal motor deficits also had a strong lateralizing value even when seizures were secondarily generalized. CONCLUSION: Postictal aphasia in temporal epilepsies and postical motor deficits in temporal and extra temporal epilepsies provided excellent lateralizing information. Postictal deficits appear to be the result of inhibitory mechanisms induced by previous ictal activity of the structures related to these functions.  相似文献   
85.
86.
PURPOSE: Uncontrolled cell proliferation, a hallmark of cancer, may result from an increased expression of cell cycle up-regulators, and/or from a reduced expression of cell cycle down-regulators. In the present study, we analyzed, by immunohistochemistry, the expression of a panel of three proteins: cyclin E and two cell cycle inhibitors, p21(Cip1/WAF1) and retinoblastoma protein (pRb) product, in different stages of papillary thyroid carcinomas (PTC). EXPERIMENTAL DESIGN: We investigated immunostaining patterns of the proteins in question in 51 resected PTC in pathologic stages, ranging from pT(1a) to pT(4), taking into consideration their relation to clinicohistopathologic factors. RESULTS: We observed a significant, progressive loss of expression of p21(Cip1/WAF1) with advancing tumor grade. The differences reached values of significance between pT(1a) [papillary thyroid microcarcinomas (PMC)] and pT(2) and between PMC and pT(4) stages of PTC. pRb presented a similar immunostaining pattern to that of p21(Cip1/WAF1) and the differences reached values of significance between pT(1a) and pT(2), and between PMC and pT(4) stages of PTC. The results of cyclin E immunostaining corresponded to our recently published result, and a negative correlation was observed between the immunostaining index of cyclin E and pRb. CONCLUSIONS: The results of the present study suggest that cyclin E expression and suppression of pRb and p21(Cip1/WAF1) may be characteristic patterns of immunostaining for PTC with a tendency to early metastasizing. If our results are confirmed in a larger study, the diagnostic panel, constructed of the antibodies against these proteins, may become a valuable tool in predicting the metastatic potential in PTC.  相似文献   
87.
PURPOSE: To establish the feasibility of capecitabine with concurrent radiotherapy (XRT) in patients with locally advanced (LA) pancreatic cancer and evaluate the effect of XRT on thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD), and tumor necrosis factor-alpha (TNF-alpha). PATIENTS AND METHODS: Fifteen patients with LA pancreatic cancer received three-dimensional conformal XRT to a dose of 50.4 Gy with capecitabine at escalating doses from 600 to 1,250 mg/m2 bid (Monday through Friday). Following chemo-XRT, stable and responding patients were treated with capecitabine 2,000 mg/m2 orally bid for 14 days every 21 days. Tumor specimens were procured with endoscopic ultrasound-guided fine-needle aspiration 1 week before and 2 weeks after chemo-XRT to evaluate TP, DPD, and TNF-alpha mRNA levels. RESULTS: Dose-limiting grade 3 diarrhea was observed in two of six patients treated at a capecitabine dose of 1,000 mg/m2 with XRT. Three patients (20%) achieved partial response. Mean percent difference in TP pre- and post-XRT was 119.2% (P = .1934). There was no significant differences in mean TNF-alpha, or DPD levels pre- and post-XRT (P = .1934 and .4922, respectively). TP and TNF-alpha levels were not significantly correlated both at pre- and post-XRT (P = .670 and P < .154, respectively). Median value of TP:DPD ratios at baseline was 2.65 (range, 0.36 to 11.08). No association between TP:DPD ratio and efficacy of capecitabine or severity of toxicities was identified. CONCLUSION: The recommended dose for phase II evaluation is capecitabine 800 mg/m2 bid (Monday through Friday) with concurrent XRT. This approach offers an easy alternative to intravenous fluorouracil as a radiosensitizer in these patients. Role of TP and TP:DPD ratio warrants further investigation in a larger clinical trial.  相似文献   
88.
89.

This cross-sectional study investigated the associations of psychosocial factors relevant to recovery from substance use disorders with monocyte activation and HIV persistence in a sample of 84 HIV-positive, methamphetamine-using sexual minority men with undetectable HIV viral load (<40 copies/mL). We examined if psychosocial factors were associated with decreased soluble CD14 (sCD14) and lower proviral HIV DNA. Multiple linear regression models adjusted for age, anti-retroviral therapy regimen, and CD4+ T-cell count. Time on ART was also included in models examining proviral HIV DNA. Greater self-efficacy for managing methamphetamine triggers and higher social support for abstinence were independently associated with lower sCD14. Greater social support for abstinence was also independently associated with lower proviral HIV DNA. Psychosocial factors relevant to recovery from substance use disorders are associated with lower monocyte activation and decreased proviral HIV DNA. Findings underscore the need for longitudinal research to identify plausible mechanisms linking psychosocial factors and substance use with biological processes relevant to HIV pathogenesis.

  相似文献   
90.

Objective

To establish the local incidence of hearing loss in newborns with Hypoxic Ischaemic Encephalopathy (HIE) and to identify associated risk factors.

Study design

Retrospective Cohort Study. Neonatal Intensive Care Unit (NICU) dual stage hearing screening protocol, including automated otoacoustic emissions (AOAE) and automated auditory brainstem response (AABR) testing.

Results

57 newborns received therapeutic hypothermia for HIE. Twelve babies (21%) died. Audiology data was incomplete in 3 babies. Complete data was available for 42 babies (male n = 24), 4 (9.5%) of whom had hearing impairment. The development of hearing loss was associated with abnormal blood glucose levels (p = 0.006), low Apgar score at 1 min (p = 0.0219) and evidence of multi organ dysfunction [high creatinine (p = 0.0172 and 0.0198) and raised liver transaminases (aspartate aminotransferase (AST) p = 0.0012, alanine aminotransferase (ALT) p = 0.0037)]. An association with gentamicin was not found.

Conclusion

This study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE. Blood glucose should be monitored carefully in these infants and developmental surveillance should include formal audiology. Further larger studies are needed to clarify the role, if any, of hypothermia per se in causation of hearing loss and to fully identify risk factors for hearing impairment in this population.

What is new

The current study confirms that hearing impairment is common in term infants who have undergone therapeutic hypothermia for moderate/severe HIE.No association between gentamicin use and the development of hearing impairment was found however initial blood glucose outside the normal range was of significance.Other factors associated with hearing impairment were low Apgar scores, greater need for resuscitation and evidence of multi organ dysfunction (renal and liver failure).  相似文献   
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