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排序方式: 共有1273条查询结果,搜索用时 328 毫秒
1.
Balloon dacryocystoplasty: indications and contraindications 总被引:3,自引:0,他引:3
2.
L. S. Alton 《Archives of environmental contamination and toxicology》1995,29(1):39-44
It was established that species of Penicillium exposed to open water bodies did not perish immediately and are adaptable. Two species of Penicillium were able to grow under extremely high doses of diesel oil, although the growth of another two species were blocked at the lowest doses of diesel oil used in our experiments. Phosphates favored growth and survival of Penicillium when their level did not exceed 6.5 g per L water. Water contaminated by nitrates or nitrites at 0.2 to 2.0 g per L was not detrimental to the growth and survival of Penicillium species. The ability of Penicillium to use these compounds as a source of carbon, nitrogen, or phosphorus, as well as their survival period in the strongly contaminated marine and river water, strictly depended on the temperature of water, the level and character of pollution and the specificity of Penicillium species. Penicilliums investigated stayed alive in highly contaminated marine and river water from 2–3 months to more than one year. 相似文献
3.
D McShane J C Davies M G Davies A Bush D M Geddes E W F W Alton 《The European respiratory journal》2003,21(1):37-42
The cystic fibrosis (CF) transmembrane conductance regulator protein can transport bicarbonate and may therefore regulate airway surface (AS) pH. Disturbances of AS pH could contribute to the pathophysiology of CF lung disease. Five studies were carried out including the following: study 1) nasal pH measurements were made in 25 CF and 10 non-CF adults using an antimony pH probe. Mean nasal pH was significantly lower in the CF group. Nasal potential difference may have been a confounding factor; study 2) in a fresh cohort of CF and non-CF subjects, no significant difference was found between the two groups using a gold pH probe; study 3) simultaneous nasal pH measurements were made in 15 CF and 15 non-CF adults using both probes. In the CF group, there was a trend for the antimony probe to read lower than the gold probe. In the non-CF group, the antimony probe read higher. The pH difference noted in study 1 related to technical factors; study 4) the effect of acute changes in serum acid/base balance on nasal pH was assessed in five non-CF adults. Nasal pH was not altered by either acute respiratory acidosis or alkalosis; study 5) nasal and lower airway pH was measured in five CF and six non-CF children. No difference was found between the groups. There was a correlation between nasal and lower airway pH. The authors conclude that airway surface pH does not differ between cystic fibrosis and noncystic fibrosis subjects and therefore, cystic fibrosis transmembrane conductance regulator may not play a major role in airway surface pH in vivo. 相似文献
4.
1. The basic defect in cystic fibrosis relates to abnormalities of ion transport in affected tissues, such as the respiratory and gastrointestinal tracts. The identification of the cystic fibrosis gene has enabled studies on the production of a cystic fibrosis transgenic mouse to be undertaken. Knowledge of normal ion transport will be necessary for the validation of any such animal model. We have therefore characterized selected responses of the murine trachea and caecum mounted in 'mini' Ussing chambers under open-circuit conditions. 2. Basal values for the trachea were: potential difference, 1.1 mV (SEM 0.2; n = 18); equivalent short-circuit current, 20.4 microA/cm2 (3.6); conductance, 18.2 mS/cm2 (1.7). Corresponding values for the caecum were: potential difference, 0.7 mV (0.1; n = 18); equivalent short-circuit current, 11.0 microA/cm2 (1.6); conductance, 14.5 mS/cm2 (1.4). 3. Amiloride (10 mumol/l) produced a significant (P less than 0.001) fall in potential difference of 43.0% (5.7) in the trachea, but had no significant effect in the caecum. 4. Subsequently, one of three protocols was used to assess the capacity of either tissue for chloride secretion. Addition of a combination of forskolin (1 mumol/l) and zardaverine (10 mumol/l) produced rises in the potential difference of 873% (509) in the trachea and 399% (202) in the caecum. Both A23187 (10 mumol/l) and phorbol dibutyrate (10 nmol/l) increased tracheal potential difference by 350% (182) and 147% (47), respectively. Neither had a significant effect in the caecum. 5. Subsequent addition of bumetanide caused a fall in the stimulated potential difference of between 39.8% and 71.7%, depending on secretagogue and tissue type.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Edward?J?HolloxEmail author Jane?Davies Uta?Griesenbach Juliana?Burgess Eric?WFW?Alton John?AL?Armour 《Journal of negative results in biomedicine》2005,4(1):9
Human beta-defensin 2 (DEFB4, also known as DEFB2 or hBD-2) is a salt-sensitive antimicrobial protein that is expressed in
lung epithelia. Previous work has shown that it is encoded in a cluster of beta-defensin genes at 8p23.1, which varies in
copy number between 2 and 12 in different individuals. We determined the copy number of this locus in 355 patients with cystic
fibrosis (CF), and tested for correlation between beta-defensin cluster genomic copy number and lung disease associated with
CF. No significant association was found. 相似文献
6.
Duncan WC; Illingworth PJ; Young FM; Fraser HM 《Human reproduction (Oxford, England)》1998,13(9):2532-2540
The molecular mechanisms involved in luteolysis are still unclear in the
primate. This study aimed to investigate the effect of induced luteolysis
on the ovarian luteinizing hormone (LH) receptor and the steroidogenic
enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset
monkey. Luteolysis was induced in the mid-luteal phase either directly by
systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal
using systemic gonadotrophin releasing hormone antagonist (GnRHant)
treatment. The LH receptor was studied by isotopic mRNA in-situ
hybridization and in-situ ligand binding and 3beta-HSD expression was
studied using isotopic mRNA in-situ hybridization and immunohistochemistry.
Induced luteolysis was associated with a reduction in the expression of LH
receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a
reduction in the LH receptor (P < 0.05) and 3beta-HSD protein
concentrations within 24 h. There were no differences in the findings
whether luteolysis was induced with PGF2alpha or GnRHant. This study shows
that disparate mechanisms to induce luteolysis in the primate result in an
identical rapid loss of the LH receptor and 3beta-HSD. In conclusion,
induced luteolysis leads to rapid loss of the steroidogenic pathway in
luteal cells.
相似文献
7.
HM Clink 《Journal of clinical pathology》1980,33(8):799-800
8.
9.
Semen parameters and testicular pathology in men with testicular cancer and contralateral carcinoma in situ or bilateral testicular malignancies 总被引:2,自引:2,他引:2
Kliesch S; Bergmann M; Hertle L; Nieschlag E; Behre HM 《Human reproduction (Oxford, England)》1997,12(12):2830-2835
We evaluated 14 patients with bilateral testicular tumour, one-sided tumour
and contralateral carcinoma in situ (CIS) of the testis or testis tumour in
single testis with respect to their fertility. We analysed semen
parameters, serum hormones [follicle-stimulating hormone (FSH), luteinizing
hormone (LH) and testosterone], testicular sonography, testicular volumes
and testicular histology prior to further anti-cancer treatment. Ten out of
14 patients showed normal or reduced sperm concentrations, while 4/14
patients were azoospermic. Serum FSH levels showed a significant negative
correlation with sperm concentrations in patients with testicular
malignancies (r = -0.64, P = 0.025). Testicular volumes revealed a
significant positive correlation with semen parameters in patients with
testes that were affected by CIS (r = 0.733, P = 0.038). We conclude that
even bilateral testicular cancer and/or CIS do not preclude fertility and,
therefore, patients should be offered andrological investigation and
therapy, including possibly surveillance strategy or the chance for
cryopreservation of the semen prior to further treatment in order to
preserve their chances for paternity.
相似文献
10.