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1.
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments.  相似文献   
2.
Diagnosis Related Group (DRG) hospital payment has begun to squeeze hospitals financially and is likely to do so in the future. This study analyzed the relationship between the volume of urologic procedures by an individual urologist, hospital costs per patient, and outcome. We used a three-year DRG database of urology patients (N = 2,980) at an academic medical center to analyze these. Low-volume urologists (arbitrarily defined by us) had higher hospital costs per patient, financial losses versus profits under DRGs, and a poorer outcome when compared with high-volume urologists. Pearson correlation showed a positive relationship between cost per patient and physician volume for nonemergency patients (-0.129, p less than 0.0001) and emergency patients (-0.368, p less than 0.0001). This may have been explained (in part) by a greater severity of illness for patients of low-volume urologists. These findings suggest, however, that the volume of urologic procedures per urologist may be related to hospital resource consumption. The health care financing environment of the future should provide substantial interest in this finding for those involved in the consumption of urologic services.  相似文献   
3.
Medifoxamine, an antidepressant agent which has an original chemical structure, has been shown through in vitro studies, utilising radioligand binding in tissue homogenates, to bind with moderately high affinity to 5-HT1c and 5-HT2 receptor subtypes and to 5-HT uptake sites (IC50 950, 980, and 1,500 nM, respectively). It has been shown to bind in vivo to rat brain 5-HT2 receptors after acute treatment with high dose (50 mg/kg, i.e., 133.9 μmol/kg). After 14 days continuous treatment with low dose (20 mg/kg, 53.6 μmol/kg), a decrease in the capacity of [3H]-5-HT uptake and a dose-dependent down-regulation of 5-HT2 receptors in rat cerebral cortex were observed. These results indicate that medifoxamine, which has been shown previously to act through dopaminergic systems, interacts also with central serotonergic neurotransmission and particularly with the 5-HT2 receptors, which could contribute to its antidepressant effect.  相似文献   
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Piezo-electric extracorporeal lithotripsy with ultrasonographic detection is performed with the following material according to the following technique: 1) A mobile firing head connected to the lumbar region by a simple inflatable cushion filled with sterile water. At the centre of the firing head, a 5 MHz real time transducer is used to locate the stone. 320 piezo-electric elements, arranged around the transducer, can induce, when focussed, a pressure of about 900 bars at the focal point in vitro. The focus is 15 mm X 5 mm. The generators are electronic. 2) The technique requires: understanding of ultrasonography in order to precisely locate the stone which, when it is intrarenal, is only missed in 1% of cases in our experience. Stones of the iliac ureter are not visible. Treatment requires the patient's confidence so that, due to the quality of the piezo-electric wave, no anaesthesia is necessary. The firing time should be relatively long (45 min to 1 hr) in order to ensure good fragmentation. 26% of patients require retreatment. Secondary complications are rare (3% of endoscopic treatments). The technique is now proposed in 90% of cases without admission to hospital. The simplicity of the manipulation of the apparatus must not mask the fact that it is a technique which requires perfect mastery. Only urologists familiar with stone pathology and who are able to treat the complications of lithotripsy by endoscopy or by surgery should perform extracorporeal lithotripsy.  相似文献   
6.
Three hundred and sixty one extracorporeal lithotripsies for renal, ureteric and bladder stones have been performed by means of a system of ultrasonographic detection and piezoelectric destruction (EDAP LT01). The localisation of the stone is achieved by a 5 MHz real time sectorial transducer situated in the centre of a small dish containing 320 piezoelectric elements concentrated in a source 5 mm wide by 15 mm high. The pressure recorded in vitro is 900 bars. The stone is easily detected in 87.2% of cases, difficult to detect in 10% of cases and impossible to detect in 28% of cases. By using a frequency of 1.25 to 5 per second, extracorporeal lithotripsy can be performed without any local, regional or general anaesthesia and without premedication in the 120 patients with a renal stone, reviewed between 1 and 3 months, 88 (73%) were considered to be complete successes. Ten (8%) were considered to be failures and 19 (21%) were considered to be partial successes. The best results were obtained in stones of the renal pelvis less than 20 mm in diameter. These results relate to a mean series which must take into account the successive improvements made to the lithotripter. Today, stone fragmentation is obtained in 93% of cases. Thirty six stones of the lumber and pelvic ureter were treated with success rates of 93% and 50%, respectively. Six bladder calculi were treated with a 50% success rate. Forty two patients were treated without being admitted to hospital.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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SMI-32, an antibody which recognizes the non-phosphorylated epitopes on the neurofilament proteins was used to study the morphological changes in the human striate cortex during postnatal development. Striate cortices from 12 autopsied patients with ages ranging from 1 day to 70 years were obtained. Using the avidin-biotin-peroxidase method, the first SMI-32 immunoreactive neurons were identified at sublayers Vb/VIa on the first postnatal day. At 5 months, the next group of neurons to develop immunoreactivity were in IVb. By 15 months, SMI-32 immunoreactive neurons were observed at III, IVa, IVb, V and VI. The changes in SMI-32 immunoreactivity (ir) were stabilized from 3 years and after. The SMI-32 ir in the striate cortex could be a useful morphological correlate for studying developmental diseases affecting the neocortex.  相似文献   
9.
To better understand the extent to which familial similarities in pulmonary function (PF) are attributable to genetic rather than to shared environmental influences, we studied the twinship aggregation of PF in 256 monozygotic (MZ) and 158 dizygotic (DZ) adult twin members of the Greater Boston Twin Registry. Genetic influences on various spirometric measures were estimated with twinship intrapair correlations adjusted using a regression model to control for similarities in the anthropomorphic characteristics of twins, and for the effects of a number of environmental factors that included childhood respiratory illness, occupational dust exposure, and smoking history. A significant influence of smoking on all air-flow measures was observed in this population for whom genetic similarities were adjusted. However, highly significant adjusted intrapair correlations for all spirometric measures, ranging from 0.52 to 0.76, were observed for the MZ twins. The intrapair correlations for the DZ twins were approximately one-half the magnitude of those for the MZ twins. These data suggest that a large proportion of the measured variability in PF may be accounted for by genetic influences other than those associated with body size.  相似文献   
10.
It has been proposed that dietary linoleic acid lowers blood pressure (BP) by being converted to arachidonic acid and prostanoids of the two-ene series. We tested the effects of linoleic acid on plasma arachidonic acid, blood pressure, blood viscosity, and RBC cation transport. Oleic acid, the major dietary monounsaturated fat and which is not a prostanoid precursor, was used as a control. Seventeen adults consumed 23 g/d of linoleic acid or oleic acid provided by genetic variants of safflower seed, each for 4 weeks in a double-blind crossover design. Linoleic and oleic acids were enriched significantly in the plasma cholesteryl esters, phospholipids and triglycerides during the respective periods of supplementation but there was no increase in arachidonate. Mean BP was 116.1/76.8 during ingestion of oleic and 113.6/74.6 during ingestion of linoleic acid (p = 0.09 systolic, p = 0.12 diastolic). The power of the study was over 75% for detecting a significant (p less than 0.05) effect of 4 mm Hg in systolic BP or diastolic BP. Whole blood and plasma viscosity, and RBC Li/Na countertransport, Na/K cotransport, and Na pump systems (Vmax) were unchanged during the protocol. Therefore, variations in dietary linoleic or oleic acids are unlikely to have major effects on BP or on several membrane-dependent erythrocyte functions related to hypertension.  相似文献   
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