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Vasopressin (AVP) receptor binding within hypothalamic sites was compared between cycling and lactating female golden hamsters. The density of AVP receptor binding was analyzed by quantitative autoradiography within the ventrolateral hypothalamus and dorsomedial hypothalamic nucleus. Lactation was correlated with a disappearance of AVP receptor binding within the ventrolateral hypothalamus. In contrast, lactation was associated with a two- to three-fold increase in the density of AVP receptor binding within the dorsomedial hypothalamic nucleus. These results suggest that AVP receptor binding within the ventrolateral hypothalamus is responsive to gonadal hormones in female golden hamsters. However, the increase in binding observed within the dorsomedial hypothalamus may be related to other neurobiological changes associated with lactation. 相似文献
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Hypertrophic smooth muscle in the partially obstructed opossum esophagus. Excitability and electrophysiological properties 总被引:1,自引:0,他引:1
Partial obstruction of the opossum esophagus leads to thickening of the circular muscle, hypertrophy of smooth muscle cells, and diminution of the extracellular space. The pharmacological and electrophysiological properties of this hypertrophied muscle were studied. Carbachol produced phasic and tonic contractions of the circular muscle. The EC50 for tonic contractions was greater for hypertrophied than for normal muscle (21.1 +/- 3.9 mumol/L vs. 4.8 +/- 2.2 mumol/L; P less than 0.05). The resting membrane potential difference of hypertrophied muscle (-50.8 +/- 0.2 mV) was similar to that of normal muscle (-50.0 +/- 0.2 mV). Electrical stimulation of intrinsic nerves in the normal muscle produced a hyperpolarization followed by a depolarization of smooth muscle membrane potential. Hypertrophied muscle responded either with an attenuated hyperpolarization or no hyperpolarization, both of which were followed by a depolarization. The space constant in the long axes of the hypertrophied circular muscle cells was greater than normal (4.4 +/- 0.2 mm vs. 3.4 +/- 0.1 mm; P less than 0.001). The threshold potential for initiation of action potentials was more negative for hypertrophied (-43.2 +/- 0.4 mV) than for normal circular muscle (-41.6 +/- 0.2 mV; P less than 0.005). These data indicate that alterations in neuromuscular function accompany the hypertrophy of esophageal smooth muscle. 相似文献
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A ventilator-dependent patient obtunded from severe head trauma suffered a spontaneous corneal perforation with lens extrusion secondary to nosocomial Pseudomonas keratitis. Despite the patient's guarded condition, a successful tectonic penetrating keratoplasty with lens removal was performed for restoration of the globe. Upon recovery, the patient's only useful vision was in her operated eye. Preventative measures against prolonged corneal exposure in an obtunded patient include copious artificial tears and lubricants, use of scleral lenses, moisture chambers, bandage contact lenses, or tarsorrhaphies. 相似文献
7.
Regional differences in oesophageal motor function 总被引:1,自引:0,他引:1
Abstract We tested the hypotheses that oesophageal bolus transit and motor function vary regionally, with bolus viscosity and with body position. In healthy volunteers, we measured the bolus head advance time, bolus presence time and bolus transit time in the proximal and distal oesophagus using water and viscous materials. We compared concurrent manometric responses. Bolus head advance time, bolus presence time and bolus transit time were longer in the distal oesophagus during water and viscous swallows in the upright and supine positions. The total bolus head advance time and transit time, measured across the entire oesophageal body, were shorter for water than viscous swallows. The amplitudes of peristaltic pressure waves were lower for viscous swallows, and varied as a function of region. These studies demonstrated true functional differences between the proximal and distal oesophagus using multichannel intraluminal impedance and that the viscosity of the bolus is a determinant of oesophageal function. 相似文献
8.
We present a report of a case of retroperitoneal actinomycosis 3 years after appendectomy for a ruptured appendix. Actinomycosis is an unusual infectious disease that occasionally occurs after enteric perforation. The literature is reviewed, and the pathogenesis, diagnosis, and treatment are discussed. 相似文献
9.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
10.
bcl-2 transgene expression promotes survival and reduces proliferation of CD3-CD4-CD8- T cell progenitors 总被引:16,自引:0,他引:16
Proliferative expansion and apoptotic cell death play prominent roles in T
cell development. The molecular control of cell cycle progression and
apoptosis appear to be inter-connected since the Bcl-2 protein can inhibit
apoptosis and slow cell cycle progression in cortical thymocytes and mature
T cells, particularly during the transition from the quiescent state into
the cell cycle. Here the impact of bcl-2 transgene expression on
CD3-CD4-CD8- T cell progenitors was assessed. Bcl-2 enhanced the survival
of these progenitors at all of the four major differentiation stages, CD25-
CD44+ (pro-T1), CD25 + CD44+ (pro- T2), CD25 + CD44- (pro-T3) and
CD25-CD44- (pro-T4). However, it reduced cell cycling and slowed turnover
only in the pro-T4 subset. From an analysis of bcl-2 transgenic mice
expressing a TCR transgene or bearing a mutation in the scid or rag-1 gene
we conclude that Bcl-2 inhibits proliferation only of T cell progenitors
that are activated via the pre- TCR, not those stimulated via c-Kit and the
IL-7 receptor.
相似文献