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1.
Having in mind the significant decrease of urinary kallikrein in rat with renal hypertension and in humans with essential hypertension, the effects of furosemide on kininogenase activity has been studied in urine of normal and hypertensive rats which received tap water or a 1% NaCl solution for drinking. Administration of 20 mg furosemide which produces maximal diuretic effect in normal rats, induced in these animals a 150–200% increase of the excretion of this enzyme after 8 hours, when compared to the activity measured before giving the drug. This increase which is observed in the normal rats drinking either water or a 1% NaCl solution shows a significant correlation with the excretion of sodium, potassium and water. In hypertensive rats, in 7 or 9 cases, an increase of kallikrein excretion (200–600%) is observed, which does not reach the levels of excretion in normal untreated rats. Furosemide did not produce increase of urinary kallikrein in hypertensive rats drinking 1% NaCl solution.  相似文献   
2.
The effectiveness of a sequential regimen consisting of mifepristone, 10 mg/day for 15 days, followed by nomegestrol acetate (NOMA), 5 mg/day for the next 13 days, for inhibiting ovulation and maintaining regular bleeding cycles was assessed in 10 surgically sterilized volunteers who were followed for one pretreatment and three treated cycles. Hormonal determinations in blood and urine, ovarian ultrasonography, bleeding records in all cycles and an endometrial biopsy taken on day 22-25 of the third treatment cycle were used to monitor the effects of treatment. During treatment, 24 monophasic (no sustained progesterone rise above 12 nmol/l) and six biphasic cycles were recorded. Nine follicular ruptures were detected echographically in these 30 treated cycles, five of which occurred in monophasic cycles. All follicular ruptures occurred on days 1-7 of NOMA treatment. Echographic and endocrine features of ovulatory cycles were both present in only four treated cycles (13.3%). Development of a secretory endometrium was achieved in all cases, but it was always irregular. Regular withdrawal bleeding occurred in all subjects and no adverse reactions were recorded. The ovarian and endometrial effects of this regimen justify testing its contraceptive effectiveness in phase 2 clinical trials.   相似文献   
3.
Several preparations of testosterone and its esters are being investigated alone or in combination with other gonadotropin-suppressing agents as possible antifertility agents for men. We studied the effectiveness of 7 alpha-methyl-19-nortestosterone (MENT) as an antispermatogenic agent in men. MENT has been shown to be more potent than testosterone and to be resistant to 5 alpha-reduction. For sustained delivery of MENT, we used a system consisting of ethylene vinyl acetate implants containing MENT acetate (Ac), administered subdermally. Thirty-five normal volunteers were recruited in 3 clinics and were randomly assigned to 1 of 3 doses: 1 (12 men), 2 (11 men), or 4 (12 men) MENT Ac implants. The initial average in vitro release rate of MENT Ac from each implant was approximately 400 micro g/day. Implants were inserted subdermally in the medial aspect of the upper arm under local anesthesia. The duration of treatment was initially designed to be 6 months. However, in 2 clinics the duration of treatment was extended to 9 months for the 2-implant group and to 12 months for the 4-implant group. Dose-related increases in serum MENT levels and decreases in testosterone, LH, and FSH levels were observed. Effects on sperm counts were also dose related. None of the subjects in the 1-implant group exhibited oligozoospermia (sperm count, <3 million/ml). Four subjects in the 2-implant group became oligozoospermic, 2 of whom reached azoospermia. Eight subjects in the 4-implant group reached azoospermia, with 1 exhibiting oligozoospermia, whereas 2 were nonresponders. Side effects generally seen with androgen administration, such as increases in erythrocyte count, hematocrit, and hemoglobin and a decrease in SHBG, were also seen in this study and were reversible. Changes in lipid parameters were moderate and transient. Liver enzymes showed small changes. This study demonstrates that MENT Ac, when administered in a sustained release fashion via subdermal implants, can inhibit spermatogenesis over a prolonged period after a single administration and has the potential to be used as a male contraceptive.  相似文献   
4.
Elevations of circulating estradiol (E2) levels due to administration of exogenous E2 accelerate embryo transport through the genital tract in pregnant rats. This study relates oviductal embryo transport to tissue E2 levels associated with blood E2 oscillations of differing profiles. Plasma E2 pulses differing in rate of increase, amplitude, and duration were achieved through various schedules of iv and sc E2 administration. Rats on the first day of pregnancy received a total dose of 5 micrograms 17 beta-E2 by short (10-15 min) or long (200-300 min) term iv infusions. Some animals were used to monitor blood and tissue levels of E2 (oviduct and diaphragm). Others were killed 24 h after treatment to assess number of embryos recovered. Fast iv infusions caused brief, high amplitude (greater than 1000 pg/ml) E2 oscillations which were ineffective in eliciting accelerated embryo transport. The longer iv infusions produced lower but sustained elevations of circulating E2 levels comparable to those achieved by sc administration and were associated with accelerated embryo transport. The oviductal E2 concentration during and after a short iv infusion was never lower than that associated with a sc injection. The lack of response to a brief, high amplitude increase in circulating E2, therefore, could not be accounted for by decreased tissue content of the hormone. These results indicate that when the total mass of E2 administered is kept constant, the magnitude of embryo transport acceleration is positively correlated with the duration and negatively correlated with the amplitude and/or slope of increase in circulating estrogen. Since different tissue content of E2 does not account for the response or no response observed it follows that the geometry of E2 oscillations in plasma has a signal value for the target cells which acts independently from the bioavailability of the hormone.  相似文献   
5.
6.

Background

Cyclooxygenase-2 (COX-2) is expressed in all female reproductive organs. Therefore, inhibitors of COX-2 may affect reproductive function. We evaluated the effect of extended administration of meloxicam on ovulation and the menstrual cycle. Our hypothesis was that meloxicam administered from menstrual cycle day 5- 22 could interfere with follicular rupture, without disrupting the menstrual cycle, and could be a potential non-hormonal contraceptive method.

Methods

The study was conducted in 56 healthy sterilized women. Before the onset of treatment and after the end of treatment, participants were observed during a control cycle to ensure that they had progesterone (P4) serum levels (> 12 nmol/l) consistent with ovulation. Participants were treated for 18 days, during three consecutive cycles. They were randomized to 15 or 30 mg/day. The menstrual cycle was monitored with serial ultrasound and hormone assays in blood.

Results

Fifty-six volunteers completed the study. In 55% of cycles treated with 15 mg/day and in 78% of cycles treated with 30mg/day (p<0.001) we observed dysfunctional ovulation defined as follicular rupture not preceded 24–48 h earlier by an LH peak or preceded by a blunted LH peak (< 21 IU/l) or not followed by an elevated serum P4 level > 12 nmol/l. Ovulation was observed in 44.6% and in 21.7% of women in the lower dose group and the higher dose group, respectively. There were no differences between the two doses in other parameters measured. There were no serious adverse events and adverse events were not different between doses or between control and treated cycles.

Conclusions

Although administration of meloxicam on menstrual cycle days 5- 22 resulted in a dose-dependent inhibition of ovulation, more than 20% of subjects had normal ovulation with the highest dose.

Implications

Previous studies have shown that oral meloxicam can delay follicle rupture. This study investigated daily oral meloxicam as a non-hormonal contraceptive. Since ovulation occurs in over 20% of cycles even with a high dose of 30 mg daily, it is not likely that the approach would be a highly effective contraceptive strategy.  相似文献   
7.
Decidual natural killer cells accumulate at the fetal-maternal interface and play a key role in a successful pregnancy. However, their origin is still unknown. Do they derive from peripheral natural killer cells recruited in decidua or do they represent a distinct population that originates in situ? Here, we identified natural killer precursors in decidua and uterus of pregnant mice. These precursors underwent rapid in situ differentiation and large proportions of proliferating immature natural killer cells were present in decidua and uterus as early as gestation day 4.5. Here, we investigated the origin of decidua- and uterus-natural killer cells by performing transfer experiments of peripheral mature natural killer cells or precursors from EGFP+ mice. Results showed that mature natural killer cells did not migrate into decidua and uterus, while precursors were recruited in these organs and differentiated towards natural killer cells. Moreover, decidua- and uterus-natural killer cells displayed unique phenotypic and functional features. They expressed high levels of the activating Ly49D receptor in spite of their immature phenotype. In addition, decidua- and uterus-natural killer cells were poorly cytolytic and produced low amounts of IFN-γ, while they released factors (GM-CSF, VEGF, IP-10) involved in neo-angiogenesis and tissue remodeling. Our data reveal in situ generation of decidual natural killer cells and provide an important correlation between mouse and human decidual natural killer cells, allowing further studies to be carried out on their role in pregnancy-related diseases.  相似文献   
8.
9.
Corneal dystrophies are distinctive clinically and histopathologically; however, variations do occur. We present two cases of stromal amyloidosis from one family masquerading other corneal dystrophy. The two cases are from a six-generation family with an autosomal dominant corneal dystrophy resembling Reis-Bucklers' dystrophy. In these cases, neither the propositus nor other family members showed typical lattice lines. Light and electron microscopy of the obtained corneal buttons disclosed amyloid stromal deposits. The clinicopathologic correlation of these cases suggests that this family represents a variant of stromal amyloid dystrophies.  相似文献   
10.
Cavitary melanocytoma of the ciliary body   总被引:1,自引:0,他引:1  
The clinical and pathologic findings of a patient with an unusual cavitary melanocytoma of the ciliary body are presented. Clinically and with ultrasonography the lesion appeared to have a cystic component. Differential diagnoses included a malignant melanoma or a cyst, and the lesion was excised by iridocyclectomy.  相似文献   
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