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101.
A new sensitive, precise, rapid and linear RP-HPLC method was developed and validated for the determination of dexrazoxane in formulations and human serum samples. Good chromatographic separation of dexrazoxane was achieved by using Kromasil C18 column. The system was operated at ambient temperature using a mobile phase consisting of methanol, 5% ortho phosphoric acid, 0.01M ammonium dihydrogen phosphate and tetrahydrofuran, pH 4.2 (10:40:30:20, v/v) isocratically at a flow rate of 1 ml/min. The method showed high sensitivity with good linearity (r2=0.9998) over the tested concentration range of 0.1 to 0.9 mg/ml. Detection was carried out at 272 nm and retention time was 7.005 min. The accuracy, formulation assay and percentage of RSD were 100.03, 97.48 and 0.03184, respectively with tailing factor (1.84). This method can be used for the routine quality control analysis.  相似文献   
102.
Prostate cancer has been widely viewed as a chemoresistant neoplasm. Perhaps, the most prevalent antimicrotubule strategy involves docetaxel administration at its maximum-tolerated dose (MTD). Although the goal is to obtain total eradication of cancer cells, debilitating toxicities are presented by docetaxel therapy, including myelosuppression, immunosuppression, gastrointestinal toxicity and peripheral neuropathy. In addition, solubility limitations necessitate infusion of high-doses intravenously once or twice a week followed by a rest period, which allows recovery of normal proliferating cells to counter-balance efficacy. An emerging notion is that more of a toxic drug at its MTD is not necessarily better. It is likely that combinatorial antimicrotubule therapy with drugs occupying different sites on tubulin may enhance efficacy while reducing toxicity. Here we show that bromonoscapine (EM011), a microtubule-modulating noscapine analog, displays synergism with docetaxel as seen by cell viability and proliferation assays. Cell-cycle data demonstrated that lower dose-levels of docetaxel (25 nM) in combination with EM011 caused an additive increase in proapoptotic activity. Since docetaxel alone caused severe mitotic arrest followed by mitotic slippage and endoreduplication, we strategized a sequential treatment regime that involved initial pretreatment with docetaxel followed by addition of EM011 to maximize mitotic arrest and subsequent apoptosis. In vivo studies with docetaxel and EM011 in combination showed a marked inhibition of tumor growth compared to docetaxel or EM011 as single-agents. Our studies suggest the potential usefulness of EM011 in the clinic to enhance docetaxel activity. This would reduce toxicity, thus improving the quality of life of docetaxel-treated patients.  相似文献   
103.
Purpose: To both characterize the clinical features of large primary open angle glaucoma (POAG) pedigree from a village in southern India and to investigate the genetic basis of their disease.

Materials and methods: Eighty-four members of a large pedigree received complete eye examinations including slit lamp examination, tonometry, gonioscopy, and ophthalmoscopy. Some were further studied with perimetry. Those diagnosed with POAG were tested for disease-causing mutations in the myocilin and optineurin genes with Sanger sequencing.

Results: Fourteen of 84 family members were diagnosed with POAG, while eight were clinically judged to be POAG-suspects. The family structure and the pattern of glaucoma in the pedigree are complex. Features of glaucoma in this pedigree include relatively early age at diagnosis (mean 50 ± 14 years) and maximum intraocular pressures ranging from 14 to 36 mm Hg with a mean of 23 mm Hg ± 6.5 mm Hg. Patients had an average central corneal thickness (mean 529 ± 37.8 microns) and moderate cup-to-disc ratios (0.74 ± 0.14). No mutations were detected in myocilin, optineurin, or TANK binding kinase 1 (TBK1).

Conclusions: We report a five-generation pedigree with a complex pattern of POAG inheritance that includes 22 POAG patients and glaucoma suspects. Although the familial clustering of POAG in this pedigree is consistent with dominant inheritance of a glaucoma-causing gene, mutations were not detected in genes previously associated with autosomal dominant glaucoma, suggesting the involvement of a novel disease-causing gene in this pedigree.  相似文献   

104.
Accumulation of beta-amyloid (Abeta) peptide in the brain is a major hallmark of Alzheimer's disease (AD). Hypercholesterolemia is a risk factor for AD and has been shown by laboratory studies to cause Abeta accumulation. Abeta levels in the brain are governed by its generation from amyloid precursor protein by beta-secretase (BACE1), degradation by the insulin degrading enzyme (IDE), clearance from the brain by the low density lipoprotein receptor-related protein (LRP-1), and transport from circulation into the brain by receptor for advanced glycation end products (RAGE). However, the mechanisms by which hypercholesterolemia causes Abeta accumulation in the brain and contributes to the pathogenesis of AD are still to be determined. In the present study, we determined the extent to which hypercholesterolemia-induced Abeta accumulation is associated with alterations in BACE1, IDE, LRP-1, and RAGE expression levels. We show that hypercholesterolemia increases Abeta production, an effect that is associated with increased levels of BACE1 and RAGE and reduced levels of IDE and LRP-1. These results suggest that reducing Abeta accumulation in the brain may require strategies that combine reduction of generation and transport of Abeta in addition to acceleration of degradation and clearance of this peptide.  相似文献   
105.
Summary Selected anthropometric measurements of 500 rural school children are reported and compared with national and American standards. Their poor nutritional status warrants an improvement in the socio-economic status and literacy of the masses and a well planned school health service programme. From the Department of Child Health, R.N.T. Medical College, Udaipur.  相似文献   
106.
Inhibition of angiogenesis may explain the delayed ulcer healing following Helicobacter pylori infection. We have previosuly demonstrated that H. pylori can inhibit endothelial cell proliferation. Some cytokines possess antiangiogenic properties. This study assessed a role for IL-6, IL-8, and TNF- in H. pylori-induced endothelial cytostasis. First, 30 l of H. pylori was coincubated with microvascular endothelial cells in the presence or absence of monoclonal antibodies to IL-6, IL-8, and TNF- for 24, 48, 72, or 96 hr. Dual labeling with propidium iodide and Hoescht 33342 distinguished between necrosis, and apoptosis and allowed viable cell numbers to be determined. H. pylori decreased cell viability after 72 and 96 hr (P < 0.02). Neither necrosis nor apoptosis was observed. Monoclonal antibodies to IL-6 and IL-8 did not reverse cytostasis. However, significant MVEC proliferation was observed in the presence of the TNF- monoclonal antibody. In conclusion, H. pylori induces cytokine up-regulation as part of its pathophysiological mechanism, which could prove detrimental to ulcer healing through an inhibitory effect on angiogenesis.  相似文献   
107.
The mechanism underlying the anticancer effect of nonsteroidal anti-inflammatory drugs (NSAIDs) is not clear. We addressed the question whether the alterations in collagen content in lung adenocarcinomas reported in previous studies result from dysregulation of gelatinolytic activity and whether the activity is altered by acetylsalicylic acid in vitro. Human lung adenocarcinomas were divided into three groups: well-differentiated (G1), moderately differentiated (G2) and poorly differentiated (G3) tumors. Each group was compared with normal lung tissue with respect to tissue collagen and collagen degradation product content (hydroxyproline assay), gelatinolytic activity (zymography) and the expression of matrix metalloproteinases, MMP-2 and MMP-9 (Western immunoblot). Moreover, in the studied tissues, the effect of acetylsalicylic acid on gelatinolytic activity was measured. The lung adenocarcinoma G1 had a similar collagen content as normal lung tissue but increased amounts of collagen degradation products and free hydroxyproline. These phenomena were accompanied by a marked increase in gelatinolytic activity (MMP-2 and MMP-9) in the G1 tumor. In adenocarcinoma G2, the free hydroxyproline content and gelatinolytic activity were increased, while the collagen and collagen degradation product contents were not markedly altered, compared to control. In contrast, adenocarcinoma G3 had an increased tissue collagen content (by about 60%), decreased percentage of collagen degradation products and similar gelatinolytic activity, compared to normal lung. Acetylsalicylic acid was found to inhibit gelatinolytic activity both in control and adenocarcinoma tissues, preferentially the active forms of gelatinases MMP-2 and MMP-9. The results suggest that human lung adenocarcinoma G1, through an elevated expression of the activated forms of both MMP-2 and MMP-9, may represent a more invasive phenotype than less differentiated tumors G2 or G3. It indicates that lung adenocarcinoma G1 should be considered as a possible target for metalloproteinase inhibitory therapy. Acetylsalicylic acid may be such a therapeutical agent in cancer prevention or early stages of tumor growth.  相似文献   
108.
Twenty-six persons from five families comprising 34 members residing in different areas of Saptari district of the eastern region of Nepal developed symptoms of epidemic dropsy over 6-8 weeks. Seventeen patients were studied during July-August 1996. The age of affected individuals varied from 3 to 75 years. Members who had not consumed food cooked in mustard oil or who were not residing with the family were spared. Mustard oil, which was used for cooking, was found to be contaminated with oil of Argemone mexicana seeds. Sanguinarine was detected in all mustard oil samples collected from the homes of affected families. Gastrointestinal symptoms were present in 82 per cent of cases a week or so prior to the onset of pedal oedema. Pitting oedema of the lower limbs, fever, and darkening of the skin were the most consistent features, found in all cases. Other prominent features such as local erythema (82 per cent) and tenderness (88 per cent) of the lower limbs were present in most cases. Two striking features not previously noted were perianal itching (100 per cent) and severe carditis (35 per cent) with congestive cardiac failure (29 per cent). Other unique features noted were 'sarcoid' skin changes (18 per cent), bilateral pleural effusion, and Roth's spots and subhyloid haemorrhages in the fundus in one patient. Other important findings were anaemia (88 per cent), hepatomegaly (41 per cent), pneumonia (35 per cent) and ascites (12 per cent). There were no deaths due to epidemic dropsy. In the majority of cases, oedema, cutaneous changes, and carditis showed a marked improvement in 2-3 weeks and patients were well after 6-8 weeks of follow-up.  相似文献   
109.
110.
Although hyaluronic acid (HA) has been used in the treatment of osteoarthritis for 30 years, the mechanism of its protective action on collagen metabolism disturbances in tissues during inflammation is not known. The present study was undertaken to evaluate the mechanism of Interleukin-1 (IL-1)-induced deregulation of collagen metabolism in cultured human skin fibroblast and the effect of HA on the process. In normal fibroblasts IL-1 strongly induced inhibition of collagen biosynthesis, while HA counteracted the process. The mechanism of this phenomenon was independent of prolidase activity, an enzyme that plays an important role in collagen biosynthesis at the post-translational level. Instead, IL-1 was found to inhibit the expression of insulin-like growth factor-I receptor (IGF-IR) and MAP kinases-ERK1 and ERK2, while HA was shown to counteract this process. Since insulin-like growth factor-I (IGF-I) is a most potent stimulator of collagen biosynthesis in fibroblasts the mechanism of IL-1-dependent inhibition of collagen biosynthesis may be related to inhibition of IGF-IR expression and signaling. The data suggest that hyaluronic acid protects collagen against IL-1-induced inhibition of biosynthesis of this protein in cultured human skin fibroblasts at the level of IGF-IR signaling.  相似文献   
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