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排序方式: 共有2637条查询结果,搜索用时 15 毫秒
1.
Anneloes Dirks Lucianne Groenink Koen G C Westphal Jocelien D A Olivier P Monika Verdouw Jan van der Gugten Mark A Geyer Berend Olivier 《Neuropsychopharmacology》2003,28(10):1790-1798
Chronically elevated levels of corticotropin-releasing factor (CRF) in transgenic mice overexpressing CRF in the brain (CRF-OE) appear to be associated with alterations commonly associated with major depressive disorder, as well as with sensorimotor gating deficits commonly associated with schizophrenia. In the present study, we tested the hypothesis that antipsychotics may be effective in normalizing prepulse inhibition (PPI) of acoustic startle in CRF-OE mice, which display impaired sensorimotor gating compared to wild-type (WT) mice. The typical antipsychotic haloperidol and atypical antipsychotic risperidone improved PPI in the CRF-OE mice, but were ineffective in WT mice. The atypical antipsychotic clozapine did not influence PPI in CRF-OE mice, but reduced gating in WT mice. This effect of clozapine in the CRF-OE mice may thus be regarded as a relative improvement, consistent with the observed effect of haloperidol and risperidone. As expected, the anxiolytic, nonantipsychotic chlordiazepoxide was devoid of any effect. All four compounds dose-dependently reduced the acoustic startle response irrespective of genotype. These results indicate that antipsychotic drugs are effective in improving startle gating deficits in the CRF-OE mice. Hence, the CRF-OE mouse model may represent an animal model for certain aspects of psychotic depression, and could be a valuable tool for research addressing the impact of chronically elevated levels of CRF on information processing. 相似文献
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Kaufmann SJ; Sharif K; Sharma V; McVerry BA 《Human reproduction (Oxford, England)》1998,13(2):498-499
The patient was diagnosed in childhood as having severe congenital
neutropenia and had recurrent admissions with severe infections. In 1987,
prior to getting married, she was sterilized. She continued to require i.v.
antibiotics when she contracted a severe infection. On one occasion, she
was treated with growth colony stimulating factor (G- CSF). Her increased
neutrophil count was sustained following this treatment. In June 1993, she
wished to start a family and underwent in- vitro fertilization (IVF)
treatment. G-CSF was given prior to oocyte retrieval. She conceived on her
first cycle and an ultrasound scan revealed a singleton pregnancy.
Throughout the course of the pregnancy, her white cell count was monitored
closely and remained at <1.0x10(9)/l. The pregnancy progressed
uneventfully and at 37 weeks gestation she was admitted for G-CSF
injections. At 38 weeks she was delivered of a boy weighing 3350 g, by
elective Caesarean section. His white cell count was normal. This is the
first case of G-CSF being used before conception and during pregnancy in a
patient with congenital neutropenia. It shows that advances in cytokine
therapy and close interdisciplinary liaison can lead to a successful
outcome and help patients, who would otherwise remain childless, to achieve
a family.
相似文献
4.
Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
The aim of the study was to determine whether a prior diagnostic testicle
biopsy can predict success or failure of testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI) in patients with
non-obstructive azoospermia caused by testicular failure, and what is the
minimum threshold of sperm production in the testis which must be surpassed
for spermatozoa to reach the ejaculate. Forty- five patients with
non-obstructive azoospermia caused by testicular failure underwent
diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure.
The diagnostic testicle biopsy was analysed quantitatively, and correlated
with the quantitative findings of spermatogenesis in patients with normal
spermatogenesis, as well as with the results of subsequent attempts at
TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure
had a mean of 0-6 mature spermatids/seminiferous tubule seen on a
diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in
men with normal spermatogenesis and obstructive azoospermia. These findings
were the same for all types of testicular failure whether Sertoli cell
only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia.
Twenty-two of 26 men with mature spermatids found in the prior testis
biopsy had successful retrieval of spermatozoa for ICSI, 12 of their
partners became pregnant, and are either ongoing or delivered. The study
suggests that 4-6 mature spermatids/tubule must be present in the testis
biopsy for any spermatozoa to reach the ejaculate. More than half of
azoospermic patients with germinal failure have minute foci of
spermatogenesis which are insufficient to produce spermatozoa in the
ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for
the presence of mature spermatids) can predict subsequent success or
failure with TESE-ICSI. Incomplete testicular failure may involve a sparse
multi-focal distribution of spermatogenesis throughout the entire testicle,
rather than a regional distribution. Therefore, it is possible that massive
testicular sampling from many different regions of the testes may not be
necessary for successful TESE-ICSI.
相似文献
5.
β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis. 相似文献
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9.
James W. Geyer Frank Hancock Charles Carrico Marilyn Kirkpatrick James Linder 《Diagnostic cytopathology》1993,9(4):417-422
A new cervical cytology monolayer preparation system called Cyto-Rich was evaluated. Using samples from 557 patients, Cyto-Rich monolayers were compared to matched conventional smears. After conventional smears were prepared and spray fixed, residual exfoliated cells were transferred to preservative fluid. The cell suspensions were gently disaggregated and the epithelial component enriched with gradient centrifugal sedimentation. The batched samples were then placed on the Cyto-Rich work station where slides are automatically prepared and stained. The results demonstrate that Cyto-Rich prepared monolayers are vastly superior to the conventional smears for cell presentation. While the study showed 99% overall concordance, Cyto-Rich improved the detection of low-grade cervical intraepithelial lesions. 相似文献
10.
Previous studies demonstrated that drug effects on the movement sequences of rats in unconditioned motor activity paradigms can be quantified by scaling measures that describe the average relationship between a variable of interest and an experimental parameter. However, rats engage in a wide variety of geometrically distinct movements that can be influenced differentially by drugs. In this investigation, the extended scaling approach is presented to capture quantitatively the relative contributions of geometrically distinct movement sequences to the overall path structure. The calculation of the spectrum of local spatial scaling exponents,f(d), is based on ensemble methods used in statistical physics. Results of thef(d) analysis confirm that the amount of motor activity is not correlated with the geometrical structure of movement sequences. Changes in the average spatial scaling exponent,d, correspond to shifting the entiref(d) function, and indicate overall changes in path structure. With the extended scaling approach, straight movement sequences are assessed independently from highly circumscribed movements. Thus, thef(d) function identifies drug effects on particular ranges of movement sequences as defined by the geometrical structure of movements. More generally, thef(d) function quantifies the relationship between microscopically recorded variables, in this paradigm consecutive (x, y) locations, and the macroscopic behavioral patterns that constitute the animal's response topography.Exemplary calculations of path segments with different geometrical characteristics can be obtained from the authors. Questions regarding the computational implementation of this method should be addressed to MPP preferably via email (martin@rat.ucsd.edu) or FAX (619-543-2493) 相似文献