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1.
E MOLKE JENSEN K. A. THIESSEN AA. CHRISTENSEN 《Acta anaesthesiologica Scandinavica》1986,30(2):109-110
The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs. 相似文献
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Factors thought to affect the success of and energy requirements for cardioversion of atrial fibrillation were studied in 80 (49 male, 31 female) patients aged 21-88 (mean 61.5 years). Transthoracic impedance was measured in advance of the countershock using a 30 kHz low amplitude AC current passed through self-adhesive ECG/defibrillator pads (diameters 8 and 12 cm) applied to the chest in the antero-posterior (AP) position in 57 patients and the anteroapical (AA) position in 23 patients. Mean transthoracic impedance for all patients was 69.3 +/- 16 (SD) ohms (range 39-131 ohms), but transthoracic impedance was significantly greater in the AA than the AP position (75.4 +/- 13 vs. 66.7 +/- 16 ohms, p = 0.02). Initial energy was 50 J (delivered) and was gradually increased to a maximum of 360 J if required. Cardioversion was successful in 73 of 80 (91.2 per cent), and low energy shocks (< or = 200 J) were successful in 45 of 80 (56.2 per cent) patients. Using single factor analysis, sex, left atrial enlargement, electrode pad positions, aetiology of atrial fibrillation, presence of left ventricular failure, and prior treatment with verapamil or beta-adrenergic blockers were not significant determinants of cardioversion success or success of low energy shocks but prior treatment with digoxin was, both for cardioversion success and success at low energies. In patients with transthoracic impedance < or = 70 ohms, low energy shocks were more often successful (33 of 50, 66 per cent) than in patients with transthoracic impedance > 70 ohms (12 of 30, 40 per cent), p = 0.04. Using univariate analysis, cardioversion success with low energy shocks was not only significantly associated with prior treatment with digoxin but also with the duration of atrial fibrillation (24 hours to less than one month and one month to three years) and for shocks of < or = 100 J, with prior treatment with amiodarone. Multifactorial linear regression analysis selected, in rank order, only duration of atrial fibrillation of 24 hours to less than one month and one month to three years as significant predictors of both cardioversion success irrespective of shock strength, and success of low energy shocks. 相似文献
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Smoking and female infertility: a systematic review and meta-analysis 总被引:11,自引:10,他引:11
The high prevalence of smoking among women in their reproductive years
continues to be a matter of concern. The negative effects of smoking on
general health are well known, but smoking may also affect fertility. The
objective of the present study was to perform a systematic review of the
literature to determine whether there is an association between smoking and
risk of infertility in women of reproductive age, and to assess the size of
this effect. In the 12 studies used for this meta- analysis, the overall
value of the odds ratio (OR) for risk of infertility in women smokers
versus non-smokers was 1.60 [95% confidence interval (CI) 1.34-1.91].
Studies of subfertile women undergoing in-vitro fertilization (IVF)
treatment also show a reduction in fecundity among women smokers. A
meta-analysis of nine studies found an OR of 0.66 (95% CI 0.49-0.88) for
pregnancies per number of IVF- treated cycles in smokers versus
non-smokers. Despite the potential limitations of meta-analyses of
observational studies, the evidence presented in this review is compelling
because of the consistency of effect across different study designs, sample
size and types of outcome. However, continued reassurance is needed that
the calculated overall effect is not in fact due to confounding variables.
相似文献
9.
Positional cloning of the gene for X-linked retinitis pigmentosa 3: homology with the guanine-nucleotide-exchange factor RCC1 总被引:6,自引:7,他引:6
Roepman R; van Duijnhoven G; Rosenberg T; Pinckers AJ; Bleeker-Wagemakers LM; Bergen AA; Post J; Beck A; Reinhardt R; Ropers HH; Cremers FP; Berger W 《Human molecular genetics》1996,5(7):1035-1041
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X-
linked RP (XLRP), has been mapped previously to a chromosome interval of
less than 1000 kbp between the DXS1110 marker and the OTC locus at
Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization
(YRH)', we have recently identified a small XLRP associated microdeletion
in this interval, as well as several putative exons including the 3' end of
a gene that was truncated by the deletion. cDNA library screening and
sequencing of a cosmid centromeric to the deletion has now enabled us to
identify numerous additional exons and to detect several point mutations in
patients with XLRP. The predicted gene product shows homology to RCC1, the
guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our
findings suggest that we have cloned the long-sought RP3 gene, and that it
may encode the GEF of a retina-specific GTP-binding protein.
相似文献
10.
Lundberg S; Rasmussen C; Berg AA; Lindblom B 《Human reproduction (Oxford, England)》1998,13(6):1490-1492
Falloposcopy is a transvaginal microendoscopic technique to explore the
human Fallopian tube from the uterotubal ostium to the fimbrial end.
Falloposcopy provides a unique possibility to visualize endotubal disease
and may be used therapeutically for removal of debris and for cutting down
filmy intraluminal adhesions. To assess the clinical performance of
falloposcopy as part of an infertility investigation, a total of 43 women
scheduled for laparoscopy as part of an investigation of infertility had a
falloposcopy performed in conjunction with the laparoscopy. All women were
investigated at Danderyd Hospital, Stockholm and Akademiska Hospital,
Uppsala, during 1995 and 1996. Images from the endosalpinx were obtained in
26 of 43 women (60.5%). In 10 women (23.3%), it was possible to obtain
images from both tubes. No images were of sufficient quality to describe
the entire tubal mucosa in detail. Falloposcopy represents a unique tool
for visualization of endotubal disease and may provide a valuable
instrument for in-vivo exploration of tubal physiology. However, certain
technical problems limit the usefulness of this method in routine clinical
practice. These technical problems have to be solved before falloposcopy
can achieve a central position in investigation and treatment of tubal
disease.
相似文献