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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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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
7.
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
8.
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
9.
H. de Lencastre I. Couto I. Santos J. Melo-Cristino A. Torres-Pereira A. Tomasz 《European journal of clinical microbiology & infectious diseases》1994,13(1):64-73
Fifteen pediatric patients as well as the five nursing staff of the Burn Unit of the Hospital D. Estefania in Lisbon, Portugal, were assayed at weekly intervals over a five-month period in order to identify the nature and number of methicillin-resistantStaphylococcus aureus (MRSA) clones associated with colonization and wound infection. Methicillin resistance was confirmed by amec-specific DNA probe. MRSA isolates were classified into chromosomal types (clones) on the basis of a variety of techniques: (i) ribotyping; (ii) restriction digestion by the endonucleaseClaI followed by Southern hybridization with themecA-specific DNA probe and (iii) by hybridization with Tn554; and (iv) pulsed-field electrophoresis (PFE) ofSmaI digests followed by (v) Southern hybridization with themecA DNA probe. A sixth, physiological technique (population analysis) was used to define the mode of phenotypic expression of methicillin resistance in each isolate. All isolates carried a single, common polymorph (ClaI type III) of themecA gene. Hybridization with Tn554 resolved these isolates to two novel patterns (alpha and beta), of which one (Tn554 alpha) was predominant (90 %). This pattern could be further resolved to four closely related PFE types (A through D). In contrast, all isolates with the Tn554 beta pattern belonged to an additional, grossly different PFE type E. The Tn554 beta class was also unique in that these bacteria carried themecA gene in aSmaI fragment smaller (about 170 kb) than that found in the alpha type strains (194 kb). Most isolates (83 %) showed a single heterogeneous (population analysis Class 3) mode of resistance expression. The data demonstrate the full capacity of the globally rare (ClaI type III) MRSA clone for colonization and virulence. The results also document the stability of the complex heterogeneous resistance phenotype as well as the stability of the chromosomal types under conditions of in vivo carriage over a period of several months. In a few isolates the samemecA polymorph was present in several, grossly different genetic backgrounds, suggesting horizontal transfer of themecA gene. 相似文献
10.
High level of unequal meiotic crossovers at the origin of the 22q11. 2 and 7q11.23 deletions 总被引:5,自引:3,他引:5
Baumer A; Dutly F; Balmer D; Riegel M; Tukel T; Krajewska-Walasek M; Schinzel AA 《Human molecular genetics》1998,7(5):887-894
Interstitial chromosomal deletions at 22q11.2 and 7q11.23 are detected in
the vast majority of patients affected by CATCH 22 syndromes and the
Williams-Beuren syndrome, respectively. In a group of 15 Williams- Beuren
patients, we have shown previously that a large number of 7q11.23 deletions
occur in association with an interchromosomal rearrangement, indicative of
an unequal crossing-over event between the two homologous chromosomes 7. In
this study, we show that a similar mechanism also underlies the formation
of the 22q11.2 deletions associated with CATCH 22. In eight out of 10
families with a proband affected by CATCH 22, we were able to show that a
meiotic recombination had occurred at the critical deleted region based on
segregation analysis of grandparental haplotypes. The incidences of
crossovers observed between the closest informative markers, proximal and
distal to the deletion, were compared with the expected recombination
frequencies between the markers. A significant number of recombination
events occur at the breakpoint of deletions in CATCH 22 patients (P =
2.99x10(-7)). The segregation analysis of haplotypes in three- generation
families was also performed on an extended number of Williams-Beuren cases
(22 cases in all). The statistically significant occurrence of meiotic
crossovers (P = 4.45x10(-9)) further supports the previous findings. Thus,
unequal meiotic crossover events appear to play a relevant role in the
formation of the two interstitial deletions. The recurrence risk for
healthy parents in cases where such meiotic recombinations can be
demonstrated is probably negligible. Such a finding is in agreement with
the predominantly sporadic occurrence of the 22q11.2 and 7q11. 23
deletions. No parent-of-origin bias was observed in the two groups of
patients with regard to the origin of the deletion and to the occurrence of
inter- versus intrachromosomal rearrangements.
相似文献