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21.
Mononuclear (macrophages) and polymorphonuclear leucocytes cells play an important role in the immunopathogenesis of acquired immunodeficiency syndrome. Zidovudine is a broad-spectrum drug used in current antiretroviral therapy. The development of controlled drug delivery systems for the treatment of chronic diseases is of great interest since these systems can act as vectors, carrying the drug only to the target, and the adverse effects can be reduced. In this study, PLA and PLA/PEG blend nanoparticles containing zidovudine were developed and their uptake by polymorphonuclear leucocytes were studied in vitro. The influence of polymer type on particle size, Zeta potential and particle uptake by polymorphonuclear leucocytes was investigated. The cells were isolated from rat peritoneal exudate and their activation by nanoparticles was measured by luminol-dependent chemiluminescence and microscopical analysis. The PEG in the blend modified the Zeta potential suggested the formation of a PEG coat on the particle surface. The phagocytosis depended on the PEG and its ratio in the blend, the results showed that the PLA nanoparticles were more efficiently phagocytosed than PLA/PEG blends. The blend with the highest PEG proportion did not prevent phagocytosis, indicating that the steric effect of PEG was concentration dependent.  相似文献   
22.
Chondromyxoid fibroma is a rare bone neoplasm characterized by chondral, myxoid and fibrous differentiation. Uncommon locations include the bone surface. Roentgenography, MRI and ultrasound can suggest the diagnosis. However, diagnosis of chondromyxoid fibroma is rarely made prior to biopsy. We present the radiologic and pathologic findings in three patients with this tumor and a review of the literature.  相似文献   
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Adherence to a Mediterranean diet (MD) is associated with a reduced risk of coronary heart disease. However, the molecular mechanisms involved are not fully understood. The aim of this study was to compare the effects of 2 MD with those of a low-fat-diet (LFD) on circulating inflammatory biomarkers related to atherogenesis. A total of 516 participants included in the Prevention with Mediterranean Diet Study were randomized into 3 intervention groups [MD supplemented with virgin olive oil (MD-VOO); MD supplemented with mixed nuts (MD-Nuts); and LFD]. At baseline and after 1 y, participants completed FFQ and adherence to MD questionnaires, and plasma concentrations of inflammatory markers including intercellular adhesion molecule-1(ICAM-1), IL-6, and 2 TNF receptors (TNFR60 and TNFR80) were measured by ELISA. At 1 y, the MD groups had lower plasma concentrations of IL-6, TNFR60, and TNFR80 (P < 0.05), whereas ICAM-1, TNFR60, and TNFR80 concentrations increased in the LFD group (P < 0.002). Due to between-group differences, participants in the 2 MD groups had lower plasma concentrations of ICAM-1, IL-6, TNFR60, and TNFR80 compared to those in the LFD group (P ≤ 0.028). When participants were categorized in tertiles of 1-y changes in the consumption of selected foods, those in the highest tertile of virgin olive oil (VOO) and vegetable consumption had a lower plasma TNFR60 concentration compared with those in tertile 1 (P < 0.02). Moreover, the only changes in consumption that were associated with 1-y changes in the geometric mean TNFR60 concentrations were those of VOO and vegetables (P = 0.01). This study suggests that a MD reduces TNFR concentrations in patients at high cardiovascular risk.  相似文献   
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ObjectiveHost defense and latency determinants in viral recurrent dermatologic infections are not entirely understood, as conventional protocols are inadequate to achieve fast healing and relapse prevention. Endogenously produced oxygen/nitrogen reactive species (ROS/RNS) are essential for antiviral immune defense, while their excess may aggravate skin inflammation. Here, we sought a nutritional approach capable of controlling ROS/RNS balance to accelerate recovery and inhibit recurrences of two mucocutaneous chronic DNA-virus infections.MethodsTwo controlled clinical trials evaluated the feasibility of ROS/RNS-modulating nutriceutical dosages of coenzyme Q10, RRR-α-tocopherol, selenium aspartate, and L-methionine associated with established therapies. Clinical trial 1 evaluated 68 patients with relapsing human papillomavirus skin warts treated with cryotherapy followed by 180 d of nutriceutical/placebo administration. Clinical trial 2 compared the combination of acyclovir followed by 90 d of nutriceutical administration versus acyclovir alone in patients with recurrences of herpes simplex genitalis (n = 60) or herpes zoster (n = 29). Viral DNA levels were assessed by polymer chain reaction, biomarkers of antiviral defense (peroxynitrite and IFNα/γ) and antioxidant capacity (lipophilic antioxidants and glutathione) were assayed by biochemical/enzyme-linked immunosorbent assay techniques in blood fractions.ResultsIn both trials, the nutriceutical induced significantly faster healing (P < 0.01-0.05) with reduced incidence of relapses (P < 0.05) as compared to control groups, which was confirmed by decreased viral load and increased antiviral cytokine and peroxynitrite plasma levels. Plasma antioxidant capacity was higher (P < 0.01) in the experimental versus control groups.ConclusionsResults document positive clinical outcomes of the selected nutriceutical associated with conventional protocols in the management of relapsing mucocutaneous human papillomavirus and herpes infections.  相似文献   
26.

Objective

This study examined which domains/symptoms from the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 15 Palliative (QLQ-C15-PAL), an abbreviated version of the health-related EORTC QLQ-C30 questionnaire designed for palliative cancer patients, were predictive of overall quality of life (QOL) in advanced cancer patients.

Methods

Patients with advanced cancer from six countries completed the QLQ-C15-PAL at consultation and at one follow-up point. Univariate and multivariate regression analyses were conducted to determine the predictive value of the EORTC QLQ-C15-PAL functional/symptom scores for global QOL (question 15).

Results

Three hundred forty-nine patients completed the EORTC QLQ-C15-PAL at baseline. In the total patient sample, worse emotional functioning, pain, and appetite loss were the most significant predictive factors for worse QOL. In the subgroup of patients with bone metastases (n?=?240), the domains mentioned above were also the most significant predictors, whereas in patients with brain metastases (n?=?109), worse physical and emotional functioning most significantly predicted worse QOL. One-month follow-up in 267 patients revealed that the significant predictors changed somewhat over time. For example, in the total patient sample, physical functioning, fatigue, and appetite loss were significant predictors at the follow-up point. A sub-analysis of predictive factors affecting QOL by primary cancer (lung, breast, and prostate) was also conducted for the total patient sample.

Conclusion

Deterioration of certain EORTC QLQ-C15-PAL functional/symptom scores significantly contributes to worse overall QOL. Special attention should be directed to managing factors most influential on overall QOL to ensure optimal management of advanced cancer patients.  相似文献   
27.
Groups of 6- to 7-day-old and 10- to 11-day-old rats received cis-dichlorodiammineplatinum (cis-DDP) or inactive trans-DDP subcutaneously and were killed after 1, 6, 10, 15, or 21 days. In both age groups the acute effect (postinjection day 1) was most obvious in the germinal external granular layer (EGL), where many cells underwent shrinkage necrosis (pyknosis, apoptosis); the latter were more frequent within the fissures than on the surface of the cerebellar folia. Cell debris were often seen to be engulfed by macrophages, Bergmann cell fibers, and meningocytes. Bergmann cell bodies were swollen and the nuclei of Purkinje cells as well as of surviving cells of the EGL were enlarged. No comparable effects were observed in animals that had received an injection of trans-DDP in the same dose. Toward postinjection (p.i.) day 6, pyknotic cells disappeared from the EGL or, after the larger doses of cis-DDP, substantially decreased in number. Small nests of pyknotic cells appeared, however, at some places of the internal granular layer (IGL). The EGL was discontinuous or thinner in both age groups. In the IGL and molecular layer (ML) multiple focal fresh hemorrhages appeared together with some macrophages. The packing cell density in the IGL was less than in the controls, especially at the top of the cerebellar folia, i.e., contrary to the distribution of the primary damage in the EGL. Later, at p.i. day 10, ectopic nests of the IGL occurred occasionally in animals injected when 10 to 11 days old and severe atrophy of the ML and Purkinje cell population was observed at some places. At p.i. days 15 to 21, invasion of microglia-like cells appeared in the IGL and in some regions of the ML. Occasionally, subpial hemorrhages occurred at this interval. The acute damage caused by cis-DDP is thus similar to the effect of X rays or some, but not all, drugs with a cytostatic action. In addition, a more profound influence on dividing cells of the EGL within the fissures and distinct capillary lesions, indicated by hemorrhages, were found after cis-DDP. As in other experimental models, the acute cis-DDP damage of the immature cerebellum was partly repaired within a few p.i. days. Spatial difference of the repair process was inferred from the packing cell density in the IGL measured at the top and bottom of the cerebellar folia.  相似文献   
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During hibernation, variation in the metabolism of nerve cells occurs. Since the cytoskeleton plays an important role in nerve cell function, we have analyzed the immunocytochemical expression of two cytoskeleton components, i.e. phosphorylated 200 kDa neurofilament protein, and microtubule-associated protein 2 in the cerebellum and optic tectum of hibernating frogs (Rana esculenta) in comparison with active animals. In addition, we have considered the immunocytochemical expression of calmodulin, which is known to be involved in neurofilament phosphorylation. In hibernating animals, there was a decrease in the immunoreactivity for phosphorylated 200 kDa neurofilament protein and microtubule-associated protein 2 of fibers in both the cerebellum and in the optic tectum. In contrast, in the large neurons of the cerebellum, i.e. Purkinje neurons, there was an increase in the immunoreactivity for microtubule-associated protein 2. The changes in the cytoskeleton components were accompanied by a decrease in calmodulin immunoreactivity in the cytoplasm of nerve cells of the cerebellum. All the changes observed are consistent with a low neuronal activity during hibernation, as also indicated by previous microdensitometric and microfluorometric data. This shows a higher degree of chromatin condensation in hibernating animals and suggests that hibernation represents a simple form of neuronal plasticity.  相似文献   
30.
Evidence has been presented that the adhesion of human spermatozoato the oolemma is mediated by integrins recognizing the Arg-Gly-Aspsequence (RGD). Fibronectin and vitronectin, glycoproteins thatcontain functional RGD sequences, are both present on humanspermatozoa, and integrins that recognize these ligands havebeen detected on spermatozoa and eggs. In this work, we studiedthe effects of oligopeptides specifically designed to blockfibronectin or vitronectin receptors on the interaction of humanspermatozoa with zona-free hamster oocytes. GRGDdSP, a peptideblocking cell attachment to fibronectin, was without effect,while GdRGDSP, which blocks both fibronectin and vitronectinreceptors, significantly inhibited the binding of human spermatozoato the oolemma of zona-free hamster eggs, in a concentration-dependentmanner, over a range 1–100 µM. As these experimentssuggested that a vitronectin receptor plays a role in sperm-oolemmaladhesion, we performed a series of experiments studying theeffects of exogenous vitronectin, when added to spermatozoaand oocytes, on gamete interactions. Sperm-oolemmal adherence,as well as sperm aggregation, was promoted by vitronectin, overa range of 2.2 nM to 1 µM, but only in the presence ofcalcium ions. We propose that vitronectin released during thesperm acrosome reaction is recognized by both gametes and playsa role in their adhesion. adhesion/gametes/vitronectin  相似文献   
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