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Urinary excretion of cross-linked N-telopeptide of type I collagen (NTx) has been reported to be a specific marker of bone resorption [18]. We assessed a new immunoassay for NTx as an indicator of changes in bone resorption caused by spontaneous menopause and compared cross-sectionally the levels of urinary NTx, hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), hydroxyproline (OH-Pr), other serum biochemical indices, and lumbar spine and proximal femur bone mineral density (BMD). Eighty-one Japanese women aged 22–77 participated in this study; 36 were premenopausal and 45 were postmenopausal. Urinary HP, LP, and NTx stayed at low levels in the premenopausal period and rose 21%, 30%, and 67% in the postmenopausal period, respectively. The rise in LP and NTx was statistically significant (P < 0.01), suggesting that NTx is mostly released from bone matrix when bone resorption is accelerated. When premenopausal women were divided into two age groups and postmenopausal women were divided into two groups according to years since menopause (YSM) there were significant differences in LP and NTx between women <4 YSM and women aged <40 and those women aged 41+ (P < 0.01 and P < 0.05, respectively). A significant 110% increase in urinary NTx and a 48% increase in urinary LP were observed in postmenopausal women compared with age-matched premenopausal women aged 45–55. All biochemical markers other than serum PTH correlated significantly with each other (r = 0.243–0.858, P < 0.05–0.0001). Urinary NTx inversely correlated with lumbar spine BMD. When postmenopausal women were divided into three groups, the correlation between bone resorption and formation markers in women 0-1 YSM was greater than in women 2–10 YSM and in women 11 + YSM, indicating that resorption and formation are coupled at the early postmenopausal period. We conclude that urinary NTx is responsive to changes in bone metabolism caused by estrogen deficiency and may be a more sensitive and specific marker than HP, LP, or OH-Pr in the early postmenopausal years. Received: 15 February 1995 / Accepted: 18 October 1996  相似文献   
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The adjuvant effect of mannan-coated liposomes on human immunodeficiency virus type-1 (HIV-1) DNA vaccine and the mechanism of this enhancement were studied. Coating of cationic liposomes with mannan significantly enhanced the ability of this vaccine to induce an HIV-specific delayed-type hypersensitivity (DTH) response. HIV-specific cytotoxic T-cell (CTL) activity elicited by DNA vaccination was also significantly enhanced with the mannan-liposome cocktail. This mannan-liposome-mediated activity was greatly inhibited by in vivo injection of anti-interferon (IFN)-gamma antibody, which suggests that IFN-gamma plays an important role in this HIV-specific immune response. The results of both isotype-specific antibody and cytokine analysis revealed that mannan-liposome-mediated DNA vaccination enhances Th1-mediated immunity.  相似文献   
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Chemosensitivity to the drugs plays a crucial role in the treatment of ovarian cancer. In this study, we evaluate the cytotoxicity of chemotherapeutic agents in six ovarian cancer cell lines; four clear cell adenocarcinoma and two serous papillary adenocarcinoma, using seven single drugs and seven sets of drug combinations with tetrazolium-based semiautomated colorimetric (MTT) assay. The drug concentration which produced 50% growth inhibition (IC50) of cisplatin was within clinically achievable range in five cell lines. The area under the curve (AUC) at IC50 of cyclophosphamide was below the clinically achievable AUC in two serous papillary cell lines. Paclitaxel was more effective in clear cells than serous papillary cells. The intensification of cytotoxicity was observed in the combinations of paclitaxel and cisplatin, and cyclophosphamide and cisplatin or 5-fluorouracil irrespective of histopathological characteristics of the original tumor. Our results indicate that ovarian cancer cell lines respond to chemotherapeutic agents heterogeneously depending upon histopathological features, indicating individualized regimens may improve survival in ovarian cancer patients.  相似文献   
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Purpose of Review

Gastrointestinal disturbances are seen in nearly all patients with Parkinson’s disease and lead to impaired quality of life, affect drug pharmacodynamics, and potentially worsen patient’s existing motor fluctuations, leading to further disability. Recent evidence links abnormal accumulations of α-synuclein aggregates in the periphery (gut) as seen in the cortex which causes dysfunctions impacting every level of the gastrointestinal tract from the esophagus, to the stomach, small bowel, colon, and rectum and can even predate the onset of the central neurologic disorder itself. Many treatments exist for the clinical phenotypes that result from the autonomic dysfunction and neuropathy involved in this neurodegenerative disorder.

Recent findings/summary

The treatments for the gut dysfunction seen in Parkinson’s disease (PD) depend on the specific area of the gastrointestinal tract affected. For dysphagia, behavioral therapies with speech pathology, neuromuscular electrical stimulation, or botulinum toxin injection may be helpful. For gastroparesis, domperidone may serve as an antiemetic while also blunting the hypotensive potential of Levodopa while new treatments such as ghrelin agonists may prove beneficial to help appetite, satiety, gastric emptying in those with constipation, and even improve constipation. Antibiotics such as rifaximin with poor systemic absorption may be used to treat small bacterial overgrowth also found in those with PD while the benefits of probiotics is yet to be determined. Finally, constipation in PD can be a reflection of pelvic floor dyssynergia, slow transit constipation, or both, thus treatments targeting the specific anorectal dysfunction is necessary for better outcomes.
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Primary malignant peripheral nerve-sheath tumors of the common bile duct are extremely rare. To our knowledge, the published literature contains no previous case report of this disease. Here we report on a 58-year-old Japanese woman with a primary malignant peripheral nerve-sheath tumor of the common bile duct, which was completely resected. A hypoechoic mass was identified in the hepatic hilus, using ultrasonography and computed tomography. Endoscopic retrograde cholangiography revealed a smooth stricture and deviation of the common bile duct. Laparotomy exposed a firm mass around the common bile duct that had not invaded the surrounding tissues. Partial resection of the common bile duct and cholecystectomy were performed as the treatment of choice. The final histopathological diagnosis was malignant peripheral nerve-sheath tumor arising from the wall of the common bile duct.  相似文献   
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Polymer dielectrics with ultra-high charge–discharge rates are significant for advanced electrical and electronic systems. Despite the fact that polymers possess high breakdown strength, the low dielectric constant (k) of polymers gives rise to low energy densities. Incorporating metal into polyimides (PI) at the polyamic acid (PAA) precursor stage of the synthetic process is a cheap and versatile way to improve the dielectric constant of the hybrid system while maintaining a high breakdown strength. Here, we explore inclusion of different percentages of Sn as a coordinated complex in a polyimide matrix to achieve metal homogeneity within the dielectric film to boost dielectric constant. Sn–O bonds with high atomic polarizability are intended to enhance the ionic polarization without sacrificing bandgap, a measurable property of the material to assess intrinsic breakdown strength. Enhancements of k from ca. 3.7 to 5.7 were achieved in going from the pure PI film to films containing 10 mol% tin.

Polyimide with high dielectric constant and breakdown strength is synthesized via tin complexation of the polyamide acid precursor. Sn–O bonds with high atomic polarizability are intended to enhance the ionic polarization without sacrificing bandgap.  相似文献   
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