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81.
目的 蜂胶除蜡后对蜂胶中黄酮类化合物含量的影响. 方法 选用紫外分光光度法,以芦丁为对照品,测定总黄酮含量. 结果蜂胶除蜡后,有8.5%的总黄酮类成分损失,但胶层与水层中总黄酮量仍大于未除蜡蜂胶的总黄酮量. 结论除蜡对蜂胶中总黄酮量影响不大,在其治疗心脑血管疾病复方制剂开发应用时可作为杂质除去.  相似文献   
82.
ObjectiveTo investigate the bioactive constituents of Shemamruthaa (SM), a herbal combination and its therapeutic effects on the mitochondrial functions with reference to lipid peroxidation (LPO), antioxidant status, citric acid cycle enzymes and electron transport chain enzymes in mammary tissues of 7,12-dimethylbenz(a)-anthracene (DMBA) induced mammary carcinoma in rat model.MethodsAdult female Sprague-Dawley rats were used for the study and were divided into four groups. Group I served as control and Group II rats were induced mammary carcinoma by administration of DMBA (25 mg/kg b.w.) orally. The normal and cancer-induced rats (Group III) were treated with SM (400 mg/kg b.w./day) orally by gastric incubation for 14 days. Group IV rats served as SM-treated control animals.ResultsCancer-induced rats showed a considerably increased level of LPO with concomitant decreased levels of antioxidants, citric acid cycle enzymes, electron transport chain enzymes and cytochrome contents in the mammary tissue. Treatment with SM brought back the aforementioned biochemical parameters to near normal.ConclusionsFrom the results, it can be inferred that Shemamruthaa possesses significant anticancer effect through its role in attenuation of LPO, prevention of membrane damage and restoring membrane integrity.  相似文献   
83.
84.

Ethnopharmacological relevance

Centaurium erythrea L. fam. Gentianaceae (CE) has been traditionally used for centuries in folk medicine of Balkans as a bitter medicinal herb for digestive complications and for treating febrile conditions and diabetes. The aim of this study was to gain insight into the chemical composition and underlying biochemical mechanism of action of the antihyperglycemic and antilipidemic activities of the dry extract of Centaurium erythrea L., wildly growing and traditionally used medicinal plant in the Republic of Macedonia.

Materials and methods

An ultrasonic methanol maceration of the aerial parts of the dried plant was performed and the extract was freeze-dried. HPLC–DAD–ESI–MSn was carried out on 150 mm×4.6 mm, 5 μm RP-18 Eclipse XDB column, at 40 °C. Mobile phase: water with 1% formic acid (A) and methanol (B) with linear gradient starting with 10% B was used to reach 15% at 5 min, 40% B at 25 min, 55% of B at 50 min and 100% at 60 min, with flow rate of 0.4 mL min−1. Normal and streptozotocin (STZ) hyperglycemic Wistar rats were used for assessment of the antihyperglycemic and antilipidemic activity by measurement of the key carbohydrate-related enzymes and substrates, as well as lipid state of the organism.

Results

HPLC–DAD–ESI–MSn analyses revealed presence of four different secoiridoids, seven flavonoid glycosides and seven xanthones in the freeze-dried extract of CE representing 53%, 25% and 22% of all compounds, respectively. The short-term (12 days) treatment of the STZ-diabetic rats with CE-extracts resulted in a 74% reduction of the produced hyperglycemia, which is only 6% less than the reduction caused by glibeclamide (GLB, positive control). The CE-extract had a significant impact on the hepatic carbohydrate metabolism enhancing the direct synthesis of glycogen, normalizing phosphorylase a activity and reducing the activity of glucose-6-phosphatase, which further causes reduction in production of blood glucose level. The long-term (45 days) treatment showed that the HbA1c in CE-treated group of animals was even lower than in the GLB-treated groups. The antilipidemic assessment of the CE-extract revealed decrease of total cholesterol, triglycerides, HDL and LDL level in the blood of the normal and STZ-hyperglycemic rats.

Conclusion

The obtained results indicate that treatment with CE extract in STZ-diabetic rats regulates the elevated level of blood glucose and carbohydrate-related disturbances slightly better than the effect of glibenclamide. There was also regulation of the serum lipid status in diabetic rats. Identified groups of bitter compounds in the extract (flavonoides, iridoids and xanthones) probably have influence on the expressed antihyperglycaemic effect.  相似文献   
85.

Ethnopharmacological relevance

Achyrocline alata is a locally marketed (Mato Grosso do Sul/ Brazil) herb used in folk medicine as an anti-inflammatory and a sedative. Evaluate the anti-inflammatory properties of Achyrocline alata in both in vivo and in vitro models.

Materials and methods

A hydroethanolic extract from inflorescences of Achyrocline alata (HEAa) was characterized by HPLC-DAD and compared to standards (chlorogenic acid; isoquercetrin; quercetin; 4,2?,4?-trihydroxy-6?-methoxychalcone; gnaphalin; 3-O-methyl-quercetin; 3,5-dicaffeoyl-quinic acid and 4,5-dicaffeoyl-quinic acid). The in vivo anti-inflammatory properties of the HEAa (4, 20 and 100 mg/kg, per os) were evaluated using the following animal models: carrageenan-induced paw edema in rats, carrageenan-induced vascular permeability and peritonitis in mice and an acetic acid-induced writhing model to test antihyperalgesic activity in mice. In vitro assays were performed to study the effects of the HEAa (0.16, 0.8 and 4 mg/ml) on the cell viability, cell spreading and production of NO and H2O2 in stimulated macrophages.

Results

The A. alata extract inhibited the development of edema and vascular permeability, reduced polymorphonuclear cell recruitment in the acute peritonitis assay and decreased the amount of writhing induced by acetic acid. The HEAa did not increase NO/H2O2 production, while it did inhibit production when the macrophages were stimulated by LPS or PMA at all tested concentrations. In the presence of HEAa, macrophage spreading did not increase even after stimulation with LPS. Additionally, the HEAa was nontoxic to macrophages at all tested concentrations.

Conclusions

The HEAa displayed anti-inflammatory and antihyperalgesic effects, which supports the use of this plant in folk medicine. These effects might be due to the flavonoids and phenylpropanoids derivatives present in the HEAa.  相似文献   
86.
ObjectiveAsthma sufferers exhibit high prevalence of anxiety/depression. Elevated tumor-necrosis factor-alpha (TNF-α) levels in peripheral system and central nervous system (CNS) are associated with anxiety/depression, whereas brain-derived neurotropic factor (BDNF) has anti-depressant effects. An anti-asthma herbal medicine intervention ASHMI inhibits peripheral TNF-α secretion in an animal model of asthma. We hypothesize that ASHMI and its compounds may have modulatory effects on CNS TNF-α and BDNF production. We sought to determine the effect of ASHMI and individual herb constituents on brain microglial cell TNF-α production, and identify the active compounds that suppress TNF-α and increase BDNF.MethodsBV-2 mouse microglial cells were pre-treated with ASHMI or extracts of Ganoderma lucidum (G. lucidum), Sophora flavescens Ait (S. flavescens), and Glycyrrhiza uralensis Fischer (G. uralensis), the herbal constituents in ASHMI, or individual compounds isolated from G. uralensis at different concentrations and then stimulated with LPS. TNF-α levels in culture supernatants were measured by ELISA. The effect of active compounds on NFκB signaling pathway and on BDNF production were determined by western blotting and ELISA, respectively.ResultsASHMI produced dose-dependent inhibition of TNF-α secretion by cultured-mouse microglia BV2 cells. Of the three herb extracts in ASHMI, only G. uralensis significantly and dose-dependently inhibited TNF-α production. Among the 5 flavonoids isolated from G. uralensis, isoliquiritigenin was the most effective. Isoliquiritigenin suppression of TNF-α production was associated with attenuation of p-NF-κB expression, and was accompanied by increased BDNF secretion.ConclusionASHMI and its effective flavonoid, isoliquiritigenin, inhibited TNF-α production by LPS stimulated microglial cells and elevated BDNF levels, which may prove to have anti-CNS inflammatory and anti-anxiety effects.  相似文献   
87.
Tephrosiapurpurea (L.) Pers. is popularly known as 'Sarapunkha" in classical Ayurvedic texts. It is a perennial plant belonging to the family Fabaceae, and occurs throughout the Indian subcontinent. T. purpurea is traditionally used to treat spleenomegaly, cirrhosis, cough and cold, abdominal swelling and as an antidote in the Ayurvedic system of medicine. Phytochemical investigations indicate the presence of semiglabrin, pongamole, lanceolatins A and B, rutin, lupeol, and β-sitosterol. Flavonoids including (+)-tephrorin A and B, (+)-tephrosone, an isoflavone, 7, 4'-dihydroxy-3', 5'-dimethoxyisoflavone and a chalcone, (+)-tephropurpurin were isolated from the whole plant. Pharmacological activities of different parts of the plant reported include anti-inflammatory, antiulcer, antimicrobial, antioxidant, antiallergic, antidiabetic, hepatoprotective, antitumor and insect repellent activity. In the present review, the literature on the phytochemical and pharmacological investigations of Tephrosia purpurea (L.) Pers. are summarized to August, 2012.  相似文献   
88.
OBJECTIVE: To study the effects of extracts from Honghua (Flos Carthaml~ on lipopolysaccharide in- duced nitric oxide (NO) production in RAW 264.7 cells and the influence of the extracts on yeast a-glucosidase activity. The total flavonoid content of the extracts was also determined. METHODS: Cytotoxicity of the extracts to RAW 264.7 cells was evaluated by the ATPliteTM method. Inhibitory effects of the extracts on NO production were evaluated by Griess assay. Curcumin was used as a positive control. Screening of extracts for po- tential a-glucosidase inhibitors was done by a fiuo- rometric assay. The assay was based on the hydroly- sis of 4-methylumbelliferyl-a-D-glucopyranoside toform the fluorescent product, 4-methylumbellifer- one. Acarbose was used as a positive control. The total t3avonoid content was tested using kaempfer- ol as the standard. RESULTS: There were significant inhibitory effects on NO production when the extracts were 25-100 μg/ mL (P〈0.05) and curcumin was 2-4 μg/mL (P〈 0.001). The extracts showed an inhibitory effect on a-glucosidase activity at the concentrations of 15.6-125 μg/mL with a half maximal (50%)inhibito- ry concentration (ICs0) of (32.8± 5.7) μg/mL, com- pared with the ICs0 of acarbose at (1.8±0.4) μg/mL. There was a significant difference between the two IC50 values (P〈0.001). The total content of flavo- noids per gram of dried herb was 1.14 mg. CONCLUSION: Honghua (Flos Carthami) showed in- hibitory effects on NO production in activated RAW 264.7 macrophage cells and an inhibitory effect on yeast a-glucosidase. There might be a relationship between these pharmacological effects and its fla- vonoid content.  相似文献   
89.

Ethnopharmacological relevance

Stem bark and fruit pulp of Hymenaea stigonocarpa Mart ex. Hayne (Fabaceae) has been popularly used to treat inflammation and gastrointestinal diseases including ulcers, diarrhea and gastric pain. The aim of this study was to investigate the intestinal anti-inflammatory activity of a methanol extract derived from the stem bark and diet with fruit pulp of Hymenaea stigonocarpa in the TNBS model of intestinal inflammation in rats.

Material and methods

The intestinal anti-inflammatory activity of stem bark extract (100, 200 and 400 mg/kg) and fruit pulp (10% and 5% in diet) was measured against the intestinal inflammatory process induced by TNBS (trinitrobenzesulphonic acid) in rats. The protective effects were evaluated as follows: evaluation of intestinal damage (damage score, extension of lesion, colon weight/length ratio), incidence of diarrhea and adherence to adjacent organs, colon glutathione (GSH) and malondialdehyde (MDA) contents, myeloperoxidase (MPO) and alkaline phosphatase (AP) activities. In addition, in vitro studies on lipid peroxidation in rat brain membranes and phytochemical profile were performed with both stem bark and fruit pulp.

Results

Treatment with 100, 200 and 400 mg/kg of stem bark extract and 10% fruit pulp flour showed protective effects in the TNBS-induced colon damage, which was related to inhibition of MPO and AP activities, reduction in colon MDA content, and counteraction of GSH depletion induced by inflammatory process. A concentration-dependent inhibitory effect on the lipid peroxidation in rat brain membranes for stem bark and fruit pulp was determined, with an IC50 value of 5.25±0.23 μg/mL and 27.33±0.09 μg/mL, respectively. Similar phytochemical composition was observed in fruit and stem bark, including mainly flavonoids, condensed tannins and terpenes.

Conclusions

Stem bark extract and fruit pulp flour of Hymenaea stigonocarpa prevented TNBS-induced colonic damage in rats and this protective effect were associated to an improvement of intestinal oxidative stress. The observed anti-inflammatory and antioxidant effects may be associated to the presence of flavonoids and tannins in the stem bark and fruit pulp of Hymenaea stigonocarpa.  相似文献   
90.
长鞭红景天化学成分的研究   总被引:10,自引:0,他引:10  
彭江南  葛永潮  李晓晖 《药学学报》1996,31(10):798-800
长鞭红景天化学成分的研究彭江南,葛永潮,李晓晖(军事医学科学院放射医学研究所,北京100850)红景天是滋补强壮药物,目前正引起人们极大的兴趣,现已有一些产品上市。我们曾对数种红景天的化学成分进行过研究[1~4]。长鞭红景天(Rhodiolafast...  相似文献   
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