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1.
Nucleotide sequences of the parathyroid (PTH) gene of 12 species of primates belonging to suborder Anthropoidea were examined. The PTH gene contains one intron that separates two exons that code the sequence of prepro and PTH, respectively. The intron of the PTH gene in Cebus apella, Callithrix jacchus, and Saguinus oedipus was 102 bp long, whereas a 103-bp intron was observed in the remaining species. Phylogenetic analysis using the nucleotide sequences of PTH revealed that these 12 species of primates of suborder Anthropoidea could be divided into two groups of the infraorder Platyrrhini (C. apella, C. jacchus, and S. oedipus) and the infraorder Catarrhini (Macaca fascicularis, Macaca fuscata, Cercopithecus aethiops, Papio hamadryas, Presbytes obscura, Hylobates lar, Pongo pygmaeus, Pan troglodytes, and Pan paniscus). The latter infraorder could be further subdivided into two subgroups belonging to the superfamily Cercopithecoidea (M. fascicularis, M. fuscata, C. aethiops, P. hamadryas, and P. obscura) and the superfamily Hominoidea (H. lar, P. pygmaeus, P. troglodytes, and P. paniscus). The deduced amino acid sequences of PTH gene between 12 species of nonhuman primates and human revealed no amino acid substitution in mature PTH among orangutans, chimpanzees, and humans. The results indicated that the PTH gene is very conserved among primates, especially between great apes and humans. The apes are the most suitable animals to be used for studying the bone metabolism and applying the knowledge to clinical use in humans.  相似文献   
2.
Aim: To investigate effects of quercetin on weight and histology of testis and accessory sex organs and on sperm quality in adult male rats. Methods: Male Sprague-Dawley rats were injected s.c. with quercetin at the dose of 0, 30, 90, or 270 mg/kg body weight/day (hereafter abbreviated Q0, Q30, Q90 and Q270, respectively), and each dose was administered for treatment durations of 3, 7 and 14 days. Results: From our study, it was found that the effects of quercetin on reproductive organs and sperm quality depended on the dose and duration of treatment. After Q270 treatment for 14 days, the weights of testes, epididymis and vas deferens were significantly increased, whereas the weights of seminal vesicle and prostate gland were significantly decreased, compared with those of Q0. The histological alteration of those organs was observed after Q270 treatment for 7 days as well as 14 days. The sperm motility, viability and concentration were significantly increased after Q90 and Q270 injections after both of 7 and 14 days. Changes in sperm quality were earlier and greater than those in sex organ histology and weight, respectively. Conclusion: Overall results indicate that quercetin might indirectly affect sperm quality through the stimulation of the sex organs, both at the cellular and organ levels, depending on the dose and the duration of treatment. Therefore, the use of quercetin as an alternative drug for treatment of male infertility should be considered. (Asian J Androl 2008 Mar. 10: 249-258)  相似文献   
3.
The anticancer agent paclitaxel is currently commercially available only as an infusion due to its low oral bioavailability. An oral formulation would be highly beneficial for patients. Besides the low solubility, the main reason for the limited oral bioavailability of paclitaxel is that it is a substrate of the efflux pump P-glycoprotein (P-gp). Recently, it has been demonstrated that P-gp can be inhibited by thiolated polymers. In this study, an oral paclitaxel formulation based on thiolated polycarbophil was evaluated in vivo in wild-type rats and in mammary cancer-induced rats. The paclitaxel plasma level after a single administration of paclitaxel was observed for 12 h in healthy rats. Moreover, cancer-induced rats were treated weekly for 5 weeks with the novel formulation. It was demonstrated that (1) co-administration of thiolated polycarbophil significantly improved paclitaxel plasma levels, (2) a more constant pharmacokinetic profile could be achieved and (3) the tumor growth was reduced. These effects can most likely be attributed to P-gp inhibition. According to the achieved results, thiolated polymers are believed to be interesting tools for the delivery of P-gp substrates such as paclitaxel.  相似文献   
4.
We determined the neurotherapeutic effects of Pueraria mirifica extract (PME) and pure puerarin (PU) in comparison with 17β‐estradiol (E2) in early‐ and late‐stage cognitive impaired rats. Rats were ovariectomized (OVX), kept for 2 and 4 months to induce early‐ and late‐stage cognitive impairment, respectively, and divided into four groups that were treated daily with (i) distilled water, (ii) 100 mg/kg of PME, (iii) 7 mg/kg of PU, and (iv) 80 µg/kg of E2 for 4 months. The estrogen deficiency symptoms of OVX rats were abrogated by treatment with E2 or PME, but not by treatment with PU. The mRNA level of genes associated with amyloid production (App and Bace1) and hyperphosphorylated Tau (Tau4) were upregulated together with the level of impaired cognition in the 2‐ and 4‐month OVX rats. Treatment with E2 reduced the level of cognitive impairment more than that with PME and PU, and 2‐month OVX rats were more responsive than 4‐month OVX rats. All treatments down‐regulated the Bace1 mRNA level in 2‐month OVX rats, while PU and PME also decreased the App mRNA level in 2‐ and 4‐month OVX rats, respectively. Only PU suppressed Tau4 expression in 2‐month OVX rats. Thus, PME and PU elicit neurotherapeutic effects in different pathways, and earlier treatment is optimal. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Southeast Asian macaques are natural hosts for a number of nonhuman primate malaria parasites; some of these can cause diseases in humans. We conducted a cross-sectional survey by collecting 99 blood samples from Macaca fascicularis in southern Thailand. Giemsa-stained blood films showed five (5.1%) positive samples and six (6.1%) isolates had positive test results by polymerase chain reaction. A phylogenetic tree inferred from the A-type sequences of the small subunit ribosomal RNA gene confirmed Plasmodium inui in five macaques; one of these macaques was co-infected with P. coatneyi. Hepatocystis, a hemoprotozoan parasite transmitted by Culicoides, was identified in an isolate that was confirmed by analysis of mitochondrial cytochrome b sequences. All malaria-infected monkeys lived in mangrove forests, but no infected monkeys were found in an urban area. These findings indicate regional differences in malaria distribution among these macaques, as well as differences in potential risk of disease transmission to humans.  相似文献   
8.

Purpose

We compared three in vivo assays, determining changes of body weight, and uterotropic and vaginal cytology assays, for the evaluation of estrogenic activity of an estrogen disrupting compound, Pueraria mirifica (PM), in comparison with 17β-estradiol (E).

Methods

Female rats were ovariectomized and gavaged with distilled water, 0.01, 0.1, 1, 10 and 20 mg/kg BW/day of E and 100 and 1,000 mg/kg BW/day of PM for 14 days. Body weights were measured weekly, and vaginal epithelium cells were monitored daily. The uterus was dissected at the end of the treatment period, weighed and examined for histomorphometry.

Results

There were a decrease in body weight and an increase in uterine weight, uterine, endometrium and myometrium areas, uterine gland numbers, and percent of cornified cell which were dependent on doses of E and PM treatments.

Conclusions

Of the three assays proposed, although all are reliable and had critical read-out, measurements of body and uterine weights is likely convenient and simple, but the uterotropic assay needs to kill the animals. Vaginal cytology assay appears most promising for sensitivity and shortening the duration of the assay. Compared to those of E, the estrogenic activity of PM at concentrations of 100 and 1,000 mg/kg BW was in the range of 14 to >20 mg/kg BW.  相似文献   
9.
OBJECTIVE: Effects of Pueraria mirifica on bone loss in fully mature ovariectomized rats are examined. METHODS: Two series of experiments were performed. In the first series, rats were kept with their ovaries intact and divided into two groups; initial control (IC) and sham control (SH). The IC rats were sacrificed on day 1 and their data were kept as baseline control. The SH rats were subjected to sham operation on day 0 and gavaged daily with distilled water for 90 days. In the second series, rats were subjected to ovariectomy, divided into five groups and gavaged daily with 0.1mg/kg B.W./day of 17-alpha-ethinylestradiol (EE), 0, 10, 100 and 1000mg/kg B.W./day of P. mirifica (P0, P10, P100 and P1000, respectively) for 90 days. Changes of bone mineral density and bone mineral content were measured using peripheral Quantitative Computerized Tomography. RESULTS: Bone loss was significantly induced by ovariectomy and it was dose-dependently prevented by P. mirifica treatment for 90 days. The preventive effects of P. mirifica on bone loss depended on bone types (axial or long bone), bone sites (metaphysis or diaphysis), and bone compartments (trabecular and cortical). At P100 and P1000, bone loss was completely prevented both in trabecular bone mineral density and content. The effects of P. mirifica were, as expected, comparable to that in the EE group. CONCLUSION: These results suggest that P. mirifica may be applicable to treat the osteoporosis in menopausal women; however, an undesirable side effect on stimulating reproductive organs should be concerned.  相似文献   
10.

Aim of the study

Butea superba Roxb. (Leguminosae) is a well-known Thai male potency herb with androgenic and anti-estrogenic activities. We evaluated whether oral administration of Butea superba has an androgenic or anti-estrogenic activity in female rats.

Materials and methods

Normal and ovariectomized adult female rats were each subdivided into five groups, DW, BS-10, BS-50, BS-250 and TP, and gavaged with 0, 10, 50 and 250 mg/kg BW/day of the crude of Butea superba and subcutaneously injected with 6 mg/kg BW/day of testosterone propionate (TP), respectively, during the treatment period.

Results

In intact rats, only BS-250 increased the uterine thickness and the number of uterine glands, and could induce a prolonged diestrous phase. In ovariectomized rats, treatment with BS-50 as well as BS-250 increased the uterine thickness and the number of uterine glands. However, serum luteinizing hormone (LH) levels were also increased. TP reduced serum follicle stimulating hormone and LH levels with the appearance of anestrous cycle, and could significantly increase the relative uterine weight and thickness and the number of uterine glands in both intact and ovariectomized rats.

Conclusions

Orally administered Butea superba tubers have an androgenic effect on the reproductive organs of intact and ovariectomized rats, and exhibit anti-estrogenic activity on LH secretion in ovariectomized rats.  相似文献   
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