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21.
22.
The antiparasitic properties of the Saussurea salsa (Pall.) Spreng. extract and its cynaropicrin fraction have been studied on a model of opisthorchosis in golden hamsters. The tested substances produced a dose-dependent therapeutic effect comparable with that of the reference antihelminthic drug biltricide (praziquantel). __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 30 – 32, August, 2005.  相似文献   
23.
There is substantial heterogeneity of symptoms and signs among women with polycystic ovary syndrome (PCOS). In addition to different diagnostic criteria used, the ethnic background of women with PCOS may affect the clinical, hormonal, and metabolic characteristics of this condition. We present here studies related to the clinical, hormonal, and metabolic characteristics and response to the treatment of PCOS in Asia, which may be different from those in Western countries. It is important to take into consideration the ethnic background of patients in future studies related to PCOS.  相似文献   
24.
BACKGROUND: Since the introduction of the Pap smear screening, the incidence of squamous cell carcinoma (SCC) has decreased significantly, but the incidence of adenocarcinoma (AC) relative to SCC has increased. AIM: To compare the Pap smear history of patients with AC and SCC of the cervix. METHODS: Patients for the study were identified from the database of Queensland Centre for Gynaecological Cancer. Patients with AC and SCC were matched for age at diagnosis and International Federation of Gynecology and Obstetrics stage. The final population included 188 matched pairs, being 376 patients in total. Data were collected upon the histological type of cancer, result of the most recent Pap smear, date and result of the Pap smear prior to the most recent Pap smear and symptoms. Chi-squared tests and Fisher's exact test were used to compare the two patient groups for several variables. RESULTS: Patients with AC had significantly more false-negative results on their most recent Pap smear (P<0.0001) than patients with SCC. The incidence of symptoms such as bleeding and/or vaginal discharge was comparable in patients with AC and SCC. The time between the most recent Pap smear and the diagnosis of cervical cancer was significantly shorter for patients with AC (P=0.01). CONCLUSIONS: Patients with AC had Pap smears more regularly than those with SCC, and their most recent Pap smear was significantly more likely to be normal. Thus, Pap smear prior to a diagnosis of AC is more likely than SCC false-negative and therefore not indicative of cervical cancer.  相似文献   
25.
The food-calcium (Ca) interaction was examined in 12 healthy women (mean age 38 years) maintained on a constant metabolic diet. They underwent three phases of study, comprised of control (no Ca), Ca citrate (1 g Ca/day) during meals, and Ca citrate separately from meals. Each phase was 7 days in length and two 24-hour urine samples were collected on days 6 and 7. The rise from the control phase in urinary Ca was slightly more prominent when Ca citrate was given with meals than without (68 and 62%, respectively). The fall in urinary phosphorus was equivalent at about 25% between Ca citrate phases. The rise in urinary citrate and pH and the decline in urinary ammonium were more prominent when Ca citrate was given with meals; however, the changes were small or nonsignificant. The urinary saturation of Ca oxalate, brushite or monosodium urate did not differ between the two Ca citrate phases. There was a nonsignificant rise in serum iron during Ca citrate phases. The results suggest that: 1) dissolution and absorption of Ca citrate might be slightly greater when given with food than without; 2) that the ability of Ca citrate to attenuate crystallization of stone-forming Ca salts in urine is not modified by food; and 3) that Ca citrate may not impair iron absorption from food.  相似文献   
26.
This paper deals with the design of the robust feedforward compensator for improving the tracking performance of control systems with gain and phase specifications. The feedforward compensator is designed for single‐input–single‐output continuous‐time linear systems with constrained input and model uncertainty. The design objective is to make the transfer characteristic from command to output be one in the presence of the input saturation and the model uncertainty. To do that, the design of the feedforward compensator is formulated as a new gain‐phase optimization problem with both the gain and phase specifications. Then, the design procedures are proposed by using frequency‐matching method based on the closed‐loop frequency response. The proposed method provides a good trade‐off between system performance and control input to overcome performance reduction due to input saturation, and guarantees the robustness of the overall system in the presence of the model uncertainty. Two design examples illustrate that the frequency characteristics and the transient response of the control system are improved by the proposed method.  相似文献   
27.
Patients with hypercalciuria have been reported to have an exaggerated response to hydrochlorothiazide (HCTZ), implying a renal tubular defect in solute reabsorption. To determine whether this disturbance is generalized or unique to a particular pathogenetic type of hypercalciuria, we measured the increments in urinary sodium (delta Na), calcium (delta Ca), and magnesium after a 100-mg dose of oral HCTZ in 10 normal subjects and 31 patients with different types of hypercalciuric nephrolithiasis. Eleven patients with renal hypercalciuria had significantly greater delta Na (P less than 0.005) and delta Ca (P less than 0.005) than the normal subjects. Ten patients with absorptive hypercalciuria and 10 patients with fasting hypercalciuria without parathyroid stimulation had delta Na and delta Ca indistinguishable from those of normal subjects. In all groups, urinary HCTZ and basal 24-h urinary Na did not differ. The results suggest that the unique natriuretic and calciuric responses to HCTZ occur only in renal hypercalciuric patients with secondary hyperparathyroidism. The data support a renal tubular defect in renal hypercalciuric in contrast to other diagnostic categories of hypercalciuric nephrolithiasis.  相似文献   
28.
In order to evaluate whether 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] could increase the serum concentration of osteocalcin (BGP) in patients with post-menopausal osteoporosis, we administered 2 micrograms/d of 1,25(OH)2D3 to 14 patients with biopsy proven osteoporosis for two weeks. An additional 13 age and sex-matched patients with osteoporosis received no drug and served as the control. Administration of 1,25(OH)2D3 significantly increased the serum concentration of 1,25(OH)2D from 31 +/- 2 SE to 56 +/- 5 pg/ml (p less than 0.01). Commensurate with the rise in 1,25(OH)2D was a significant increase in BGP from 3.9 +/- 0.6 to 6.4 +/- 0.9 ng/ml (p less than 0.001). There were no significant changes for these parameters in the control group. It is concluded that short term 1,25(OH)2D3 administration is effective in raising BGP concentrations in patients with post-menopausal osteoporosis.  相似文献   
29.
An apparently unique presentation of osteoporosis was encountered in eight postmenopausal women (mean age, 56.8 yr). They had renal hypercalciuria, since they had fasting hypercalciuria [0.17 +/- 0.04 (+/- SD) mg/100 ml glomerular filtrate (GF)] in the setting of normocalcemia and parathyroid stimulation (high serum immunoreactive PTH and/or urinary cAMP). Serum 1,25-dihydroxyvitamin D was not significantly different (28 +/- 7 vs. 34 +/- 2 pg/ml) from that in a nonelderly control group, but fractional intestinal calcium (Ca) absorption was significantly lower (0.382 +/- 0.123 vs. 0.49 +/- 0.06; P less than 0.025). Thus, the patients did not have compensatory intestinal hyperabsorption of Ca despite PTH excess. Treatment with hydrochlorothiazide (50 mg/day) produced a decline in fasting urinary Ca (to 0.07 +/- 0.02 mg/100 ml GF; P less than 0.01), serum PTH (from 39 +/- 19 to 21 +/- 1 microliters eq/ml; P less than 0.05), and urinary cAMP excretion (from 5.30 +/- 0.57 to 3.57 +/- 0.59 nmol/100 ml GF; P less than 0.0025). The results suggested that hyperparathyroidism was secondary. Histomorphometric analysis of bone showed reduced trabecular bone volume without mineralization defect, compatible with osteoporosis. Four of eight patients had high or high normal fractional resorption surfaces, fractional formation surfaces, and fractional osteoid volumes. That these abnormalities may reflect PTH-dependent osteoclastic resorption and bone turnover was supported by the reduction of these indices after correction of secondary hyperparathyroidism with hydrochlorothiazide therapy. The remaining four patients, however, had normal histomorphometric results. In summary, postmenopausal osteoporosis may occur sometimes with renal hypercalciuria and secondary hyperparathyroidism. The lack of compensatory intestinal hyperabsorption of Ca predisposes to negative Ca balance, and the hyperparathyroid state may be manifested by stimulated osteoclastic and osteoblastic activities.  相似文献   
30.
We report a case of an 83-year-old gentleman presenting with acute low back pain and radicular left lower extremity pain after golfing. A magnetic resonance imaging (MRI) of the lumbar spine revealed a low-signal-density lesion compressing the L5 nerve. A computed tomography scan was then ordered, confirming an extra-foraminal disc protrusion at the L5–S1 level, containing a focus of gas that was compressing the left L5 nerve root and communicating with the vacuum disc at L5–S1. After a failed left L5 transforaminal epidural steroid injection, the patient was brought back for a percutaneous intradiscal aspiration of the vacuum disc gas. This resulted in immediate relief for the patient. A follow-up MRI performed 2 months after the procedure found an approximate 25% reduction in the size of the vacuum disc herniation. Six months after the procedure, the patient remains free of radicular pain. This case report suggests that a percutaneous aspiration of gas from a vacuum disc herniation may assist in the treatment of radicular pain.  相似文献   
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