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81.
Zelinski-Wooten MB; Slayden OD; Chwalisz K; Hess DL; Brenner RM; Stouffer RL 《Human reproduction (Oxford, England)》1998,13(2):259-267
Large doses of antiprogestin typically disrupt menstrual cyclicity. A
chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which
permits continued menstrual cyclicity but alters gonadal- reproductive
tract activity, was established. Rhesus monkeys received vehicle (n = 6) or
0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight
daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and
gonadotrophin profiles were normal during cycles involving vehicle and 0.01
and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle
oestradiol and gonadotrophin surges, and subsequent progesterone
production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied
by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half
the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group
were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of
C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and
cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily
treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in
macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed
ovarian cyclicity, menstruation was disrupted in some animals. Increasing
the dose to 0.1 mg/kg antagonized pituitary function and resulted in
anovulation and amenorrhoea. A chronic low-dose regimen of the
antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity,
has potential as a contraceptive in women.
相似文献
82.
These studies measured changes in blood pressure and heart rates of 15-day-old SHR and WKY rat pups immediately following milk ingestion using three different methods of milk delivery. In the first experiment milk ejections were induced, using IV oxytocin, from the pups' natural mothers, while in the second experiment ejections were elicited from Marland Farms Wistar foster mothers. In the last experiment cow's milk was delivered using tongue cannulas and no mother was present. In each case we found that the dramatic increases in blood pressure associated with milk ingestion were larger in the SHR pups, while heart rate changes tended to be larger in the WKY. We also found that the dynamics of these cardiovascular responses to feeding were significantly altered by the presence of the mother. 相似文献
83.
Construction of cosmid contigs and high-resolution restriction mapping of the Huntington disease region of human chromosome 4 总被引:1,自引:0,他引:1
Zuo Jlan; Robblns Carolyn; Bahariloo Slamak; Cox David R.; Myers Richard M. 《Human molecular genetics》1993,2(7):889-899
The gene responsible for Huntington disease (HD) has been localizedto a 2.2 million base pair (Mbp) region between the loci D4S10and D4S98 on the short arm of human chromosome 4. As part ofa strategy originally designed to clone the gene based on itschromosomal location, we and others previously identified overlappingyeast artificial chromosome (YAC) clones covering most of thisregion. While these YAC clones were useful for initially obtaininglong-range clone continuity, a number of features of the YACsindicated that smaller clones are generally more useful in thesubsequent steps of the positional cloning strategy. In thispaper, we use these YAC clones to generate sets of overlappingcosmid clones covering most of the HD region. We Isolated alarge number of cosmids by screening a chromosome 4-specificcosmld library with labeled DNA from a minimal overlapping setof YAC clones. These cosmid clones were further analyzed byrestriction mapping and hybridization experiments, leading tothe assembly of 185 cosmids Into eleven contigs covering morethan 1.65 Mbp and to a fine-structure restriction map of theregion. Nine of these contigs cover 90 percent of the 1.7 Mbpsubregion between loci D4S125 and D4S98 where the HD gene isnow known to lie. The detailed restriction map and the cosmidclones should facilitate the identification and localizationof cDNAs and polymorphic markers, and they provide reagentsfor large scale DNA sequencing of this region of the human genome.Our results suggest that this strategy should be generally usefulfor converting YAC clones into cosmid contigs and generatinghigh-resolution restriction maps of genomioc regions of interest. 相似文献
84.
Objective: To present the case of a 17-year-old male soccer goalkeeper who sustained maxillofacial fractures and dental trauma after being struck in the face by an opponent's knee.Background: Because of the nature of the sport and a lack of protective headgear, soccer players are at risk for sustaining maxillofacial trauma. Facial injuries can complicate the routine management of on-field medical emergencies often encountered by certified athletic trainers. The appropriate management of maxillofacial trauma on the playing field may help to reduce both the immediate and long-term morbidity and mortality associated with these injuries.Differential Diagnosis: Lacerated superior labial artery, lacerated upper lip, dental fractures, maxillofacial fractures, orbital blowout fracture, closed head injury, cervical spine injury, cerebrovascular accident.Treatment: The athlete received immediate on-field medical care and was subsequently transported to the hospital, where diagnostic testing was performed and further treatment was provided. Hospital inpatient management included dental and plastic surgery. After discharge from the hospital, the athlete underwent several additional dental procedures, including gingival surgery and nonsurgical endodontic treatments. The fractures were followed closely to assure that adequate healing had occurred. The athlete did not return to soccer.Uniqueness: Certified athletic trainers need to be prepared for on-field medical emergencies. Bleeding associated with maxillofacial trauma can complicate basic medical interventions such as airway maintenance. Inappropriate on-field management may result in unnecessary morbidity and mortality for the injured athlete. Therefore, immediate recognition of the severity of the injury is needed in order to institute appropriate airway-management strategies.Conclusions: It is sometimes necessary to consider nonstandard methods of airway management in order to first address heavy bleeding that may be associated with facial trauma. Achieving hemostasis is essential in order to prevent potentially life-threatening complications related to hemorrhage, such as airway obstruction and hypovolemic shock. 相似文献
85.
Sahni R Schulze KF Kashyap S Ohira-Kist K Fifer WP Myers MM 《Developmental psychobiology》2000,37(2):73-81
To provide insight into the maturation of neural mechanisms responsible for variability in heart rate during quiet and active sleep, 6-hour continuous electrocardiographic recordings and simultaneous minute-by-minute behavioral activity state assignments were performed in 61 healthy, growing low birth weight infants. The infants weighed 795-1600 g at birth and ranged between 31-38 weeks in postconceptional age. During this age interval there was a decrease in heart rate during quiet sleep and an increase in both time domain and frequency domain measures of the variability in cardiac interbeat intervals. In quiet sleep, global variability, measured as SD of R-R intervals, increased in relation to age, as did higher frequency variability, measured as the square root of the mean of squared successive differences in R-R intervals. Developmental changes in the 0.5-2.0 Hz spectral power band of RR-interval variability, another measure of high frequency variability, paralleled the changes seen in the time domain measure. Evaluation of patterns of changes in the magnitude and direction of successive interbeat intervals provided evidence that the incidence of sustained accelerations or decelerations increased whereas the incidence of no change in consecutive RR-intervals decreased as infants matured. Among the various measures of heart rate variability, the incidence of sustained change and no change in successive interbeat intervals were most closely related to postconceptional age in both sleep states. The overall decrease in heart rate, increase in heart rate variability, and increase in the pattern of changes in interbeat interval with postconceptional age are consistent with the maturation of the autonomic cardio-regulatory activity from 31-38 weeks age. 相似文献
86.
87.
Aikens JE Michael E Levin T Myers TC Lowry E McCracken LM 《Journal of behavioral medicine》1999,22(6):605-617
Although comparative studies differentiate noncardiac chest pain (NCCP), panic disorder, and coronary artery disease (CAD), little research has examined the defining features of NCCP, such as cardiac complaints, medical utilization, and learning history. We administered self-report measures to 80 Emergency Department (ED) patients with a primary complaint of chest pain who were subsequently found to not have CAD. Forty-eight percent of the ED utilization variance was accounted for by NCCP duration, age, cardiac distress symptoms, and prior exposure to both siblings' and friends' cardiac distress symptoms. In turn, 67% of the variance in cardiac distress symptoms was explained by education, age, NCCP duration, number of illnesses, noncardiac panic symptoms, prior exposure (friends), and prior observation of others' cardiac distress. No effects emerged for gender, ethnicity, avoidance, or depression. Results suggest that beyond the effects of age and distress intensity, prior exposure to other people's cardiac distress may influence NCCP. 相似文献
88.
Peripheral neuropathy in the Twitcher mutant. A new experimental model of endoneurial edema 总被引:3,自引:0,他引:3
H C Powell R L Knobler R R Myers 《Laboratory investigation; a journal of technical methods and pathology》1983,49(1):19-25
The Twitcher mouse (Twi/Twi) is a recently identified mutant experimental model for human globoid leukodystrophy. Affected mice develop neurologic abnormalities with demyelination of white matter and peripheral nerve due to an inherited enzyme deficiency. The neuropathy has unusual pathologic features:severe interstitial edema and infiltration by eosinophils. To investigate its pathogenesis and to identify the mechanism of demyelination, we studied vascular permeability and measured endoneurial fluid pressure. Significantly increased endoneurial fluid pressure was detected in clinically affected animals (average, 6.4 cm H2O) versus controls (1.7 cm H2O), and these data are the first measurements of EFP to be reported in mice. Increased vascular permeability to horseradish peroxidase was visualized by electron microscopy with leakage of horseradish peroxidase between endothelial cells and flooding of the endoneurial interstitium. Numerous eosinophils were present in the interstitium, as well as some polymorphonuclear cells, occasional erythrocytes, and degranulating mast cells. Abnormalities of nerve fibers included swelling of Schwann cells with intracytoplasmic inclusions, demyelination, and remyelination. As well as being a model for globoid leukodystrophy, the Twitcher is the first spontaneously occurring experimental model for endoneurial edema and increased endoneurial fluid pressure. 相似文献
89.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
90.
Undar A Zapanta CM Reibson JD Souba M Lukic B Weiss WJ Snyder AJ Kunselman AR Pierce WS Rosenberg G Myers JL 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2005,51(1):56-59
Unreliable quantification of flow pulsatility has hampered many efforts to assess the importance of pulsatile perfusion. Generation of pulsatile flow depends upon an energy gradient. It is necessary to quantify pressure flow waveforms in terms of hemodynamic energy levels to make a valid comparison between perfusion modes during chronic support. The objective of this study was to quantify pressure flow waveforms in terms of energy equivalent pressure (EEP) and surplus hemodynamic energy (SHE) levels in an adult mock loop using a pulsatile ventricle assist system (VAD). A 70 cc Pierce-Donachy pneumatic pulsatile VAD was used with a Penn State adult mock loop. The pump flow rate was kept constant at 5 L/min with pump rates of 70 and 80 bpm and mean aortic pressures (MAP) of 80, 90, and 100 mm Hg, respectively. Pump flows were adjusted by varying the systolic pressure, systolic duration, and the diastolic vacuum of the pneumatic drive unit. The aortic pressure was adjusted by varying the systemic resistance of the mock loop EEP (mm Hg) = (integral of fpdf)/(integral of fdt) SHE (ergs/cm3) = 1,332 [((integral of fpdt)/(integral of fdt))--MAP] were calculated at each experimental stage. The difference between the EEP and the MAP is the extra energy generated by this device. This difference is approximately 10% in a normal human heart. The EEP levels were 88.3 +/- 0.9 mm Hg, 98.1 +/- 1.3 mm Hg, and 107.4 +/- 1.0 mm Hg with a pump rate of 70 bpm and an aortic pressure of 80 mm Hg, 90 mm Hg, and 100 mm Hg, respectively. Surplus hemodynamic energy in terms of ergs/cm3 was 11,039 +/- 1,236 ergs/cm3, 10,839 +/- 1,659 ergs/cm3, and 9,857 +/- 1,289 ergs/cm3, respectively. The percentage change from the mean aortic pressure to EEP was 10.4 +/- 1.2%, 9.0 +/- 1.4%, and 7.4 +/- 1.0% at the same experimental stages. Similar results were obtained when the pump rate was changed from 70 bpm to 80 bpm. The EEP and SHE formulas are adequate to quantify different levels of pulsatility for direct and meaningful comparisons. This particular pulsatile VAD system produces near physiologic hemodynamic energy levels at each experimental stage. 相似文献