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41.
Despite evident interest in age-related bone changes, data on regional differences within the proximal femur are scarce. To date, there has been no comprehensive study on site-specific age-related changes in the trabecular architecture of three biomechanically important femoral subregions (medial neck, lateral neck, and intertrochanteric region) for both genders. In this study we investigated age-related deterioration in the trabecular architecture of those three subregions of the femoral neck for both genders. The research sample included 52 proximal femora (26 males, 26 females; age range, 26–96 years) from Forensic Department at University of Belgrade. Bone sections from the three regions of interest were scanned by micro-CT at University of Hamburg. The study revealed that proximal femoral microarchitecture cannot be perceived as homogeneous and, more importantly, that the aging process is not uniform. Besides the initial intersite differences, microarchitecture changed differently with increasing age, maintaining significant differences between the regions. In addition, we observed a different aging pattern between genders: deterioration was most significant in the intertrochanteric region in women, while the lateral neck was most affected in men. This finding supports epidemiological data about the differential occurrence of cervical vs. trochanteric fractures in aging males and females. In conclusion, the aging process in the proximal femur cannot be regarded as a simple function of quantitative bone loss but, rather, as an alteration of specific architecture that may degrade bone strength.  相似文献   
42.
The data about the fatty acid (FA) status of non-Hodgkin lymphoma (NHL) patients are poor. Therefore, the aim of this study was to investigate the FA profile of serum phospholipids in NHL patients related to the aggressiveness and clinical stage of NHL. We analyzed the FA profile of serum phospholipids in 47 newly diagnosed, untreated NHL patients and in 29 healthy subjects. Significantly higher (p?<?0.001) levels of palmitic (16:0), oleic (18:1 n-9) and arachidonic acids (20:4 n-6), saturated and monounsaturated FA were found in NHL patients, while linoleic acid (18:2 n-6) and the levels of total polyunsaturated FA (PUFA), n-3 PUFA, eicosapentaenoic (20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) were significantly reduced (p?<?0.01). The level of oleic acid in patients with indolent NHL was significantly lower (p?<?0.05) than in more aggressive types of disease. Contents of palmitoleic acid, docosatetraenoic (22:4 n-6), and PUFA was lower in very aggressive NHL. According to clinical stage (CS), patients with CS I had significantly higher SFA and lower n-6 FA than other three groups, and group with CS IV showed significantly decreased DHA and n-3 PUFA. Our results showed an abnormal FA profile in serum phospholipids in NHL patients.  相似文献   
43.
The study was designed to evaluate and compare the effects of single oral (or) and intraperitoneal (i.p.) cadmium (Cd) administration on parameters of oxidative stress in liver of rats. Furthermore, investigation on protective effects of magnesium (Mg) or and i.p. pretreatment on the same parameters was performed. Wistar rats were administrated oral dose of Cd (30 mg Cd/kg b.w.)/Cd+Mg (30 mg Cd/kg b.w., 50 mg Mg/kg b.w.) or i.p. dose of Cd (1.5 mg Cd/kg b.w.)/Cd+Mg (1.5 mg Cd/kg b.w., 3 mg Mg/kg b.w.) and sacrificed after 24 h. In liver homogenates superoxide anion, malondialdehyde, non-protein sulfhydryl groups, total sulfhydryl groups content, and superoxide dismutase activity were determined. Cadmium intoxication caused the increase of superoxide anion and malondialdehyde levels and had negative effect on investigated parameters of antioxidant defense system, except on total sulfhydryl groups. The negative effect was more emphasized after i.p. Cd administration. Oral Mg pretreatment induced more pronounced positive effect than Mg given intraperitoneally that can be attributed, at least partly, to Cd and Mg interactions on the level of GIT. On the basis of the obtained results it can be concluded that both Cd and Cd+Mg effects on parameters of oxidative stress in rats liver are route-dependent.  相似文献   
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Preclinical studies have shown that nitric oxide (NO)-donating nonsteroidal anti-inflammatory drugs possess anticancer activities. Here, we report in vitro and in vivo studies showing the antitumor effect of the NO-donating isoxazole derivative (S,R)-3-phenyl-4,5-dihydro-5-isoxazole acetic acid (GIT-27NO). GIT-27NO, but not the NO-deprived parental compound VGX-1027, significantly affected viability of both rodent (L929, B16, and C6) and human (U251, BT20, HeLa, and LS174) tumor cell lines. GIT-27NO triggered either apoptotic cell death (e.g., L929 cells) or autophagic cell death (C6 and B16 cells). Moreover, GIT-27NO hampered the viability of cisplatin-resistant B16 cells. NO scavenger hemoglobin completely prevented GIT-27NO-induced death, indicating that NO release mediated the tumoricidal effect of the compound. Increase in intracellular NO upon on the treatment was associated with intensified production of reactive oxygen species, whereas their neutralization by antioxidant N-acetylcysteine resulted in partial recovery of cell viability. The antitumor activity of the drug was mediated by the selective activation of mitogen-activated protein kinases in a cell-specific manner and was neutralized by their specific inhibitors. In vivo treatment with GIT-27NO significantly reduced the B16 melanoma growth in syngeneic C57BL/6 mice. The therapeutic effect occurred at dose (0.5 mg/mouse) up to 160 times lower than those needed to induce acute lethality (80 mg/mouse). In addition, a dose of GIT-27NO five times higher than that found effective in the melanoma model was well tolerated by the mice when administered for 4 consecutive weeks. These data warrant additional studies to evaluate the possible translation of these findings to the clinical setting.  相似文献   
47.
Central vision loss, photopsia, floaters, and macular edema in a highly myopic patient can easily be misinterpreted as high myopia complications. In atypical cases, detailed examination and a thorough diagnostic workup are required to establish the proper diagnosis, which is often beyond the scope of diagnoses initially considered.  相似文献   
48.

Objective

To investigate the spatial and temporal expression of proliferation Ki-67 marker, pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins during early development of the human tooth.

Materials and methods

Histological sections of eight human conceptuses, 5–10 postovulatory weeks old, were used for immunolocalization for Ki-67, Bax and Bcl-2 markers. Quantification was performed by calculating the fraction of Ki-67 positive cells, expressed as a mean ± SD, and analysed by Mann–Whitney test, Kruskal–Wallis and Dunn's post hoc test.

Results

In 6th–7th developmental weeks, the tooth germ and dental crest contained 37% of proliferating cells, which increased to 40% in the 8th week, and then decreased to 15% in the 10th week, whilst the proliferation in the ectomesenchyme subsequently dropped from 37% to 23%. Epithelial parts of the enamel organ displayed similar proliferation activity (31–36%), dental crest 10%, whilst enamel knot showed no proliferating activity. The tooth ectomesenchyme contained more proliferating cells (50%) than the jaw ectomesenchyme (35%), and both dropped to 28% in the 10th week. Ectomesenchyme between the tooth germs contained 23%, whilst the jaw ectomesenchyme contained 15% of proliferating cells. Bcl-2 expression had following pattern: strong in proliferating cells, moderate in tooth germs and dental crest, and weak in the ectomesenchyme. Bax co-expressed with Bcl-2 in the tooth germ and dental crest. In the reticulum and inner enamel epithelium Bcl-2 had prevalent expression, whilst Bax prevailed in the outer enamel epithelium and tooth ectomesenchyme.

Conclusions

Proliferating cells most likely influence growth of the tooth germ, Bcl-2 affects proliferation and differentiation of specific cell lineages, whilst Bax influences process of cell death.  相似文献   
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The 43rd European Congress of Cytology in Wrocław, Poland, was held as a hybrid meeting in the Fall of 2021. After nearly 2 years without in-person cytology conferences, the 43rd Congress represents 1 of the first major international scientific meetings to occur during the severe acute respiratory syndrome-coronavirus 2 pandemic. Since March 2020, the pandemic situation substantially modified the organization of scientific meetings because of both domestic and international travel restrictions, new health standards, and concern among participants, resulting in new alternative forms of virtual conferencing. Cancer (Cancer Cytopathol) 2022;130:000-000. ;  相似文献   
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