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41.
Cell surface glycosylation diversity of embryonic thymic tissues 总被引:1,自引:0,他引:1
In the thymus, glycosylation status of many cell surface molecules changes during the thymocyte maturation and selection processes. In this study, we evaluated the glycosylation changes and possible relationships with programmed cell death in the thymic tissues from mouse embryos at the days 14 (E14), 15 (E15), 16 (E16), 17 (E17) and 18 (E18) of embryonic development. In order to determine glycosylation changes we used three different plant lectins: peanut agglutinin (PNA), Maackia amurensis leucoagglutinin (MAL or MAAI) and Sambucus nigra agglutinin (SNA), which recognize core disaccharide galactose (1-3) N-acetylgalactosamine [Galbeta(1-->3)GalNAc], sialic acid linked (2-->3) to galactose [SAalpha(2-->3)Gal] and sialic acid linked to galactose [SAalpha(2-->6)Gal] structures, respectively. Our lectin histochemistry and lectin blotting studies indicated that glycosylation pattern was modified in thymocytes at the embryonic developmental stages analyzed. The immature cortical thymocytes were labeled by PNA, whereas medullary thymocytes were positive for MAL and SNA binding. Many medullary thymocytes exhibited alpha(2-->6)-linked sialic acid on their surface and this increased throughout the gestational stages. In the lectin blotting studies, different protein bands of various molecular weights were identified in thymocytes. Two of them were putatively identified as CD43 and CD45 glycoproteins. In addition, TUNEL (deoxynucleotdyltransferase-mediated dUDP nick end labeling) indicated that only PNA-positive cortical thymocytes were deleted in all embryonic stages. These results indicate that the glycosylation pattern was modified in thymocytes at all embryonic developmental stages, and these modifications can affect the T cell deletion, probably via the galectin-1 molecule in the embryonic thymus. 相似文献
42.
Objectives: Genetic variants in Toll-like receptors (TLRs) are considered a potential indicator for host susceptibility to and outcome of several infectious diseases including tuberculosis. The aim of this study was to determine whether −129 C/G and Met1Val polymorphisms of TLR8 were associated with pediatric pulmonary tuberculosis in Turkish population.
Methods: The −129 C/G and Met1Val polymorphisms were studied in 124 children with pulmonary tuberculosis compared to 150 age-matched healthy control subjects.
Results: We did not identify any statistically significant differences between the patients with TB and control groups with regard to the frequency of genotypes GG or G/(−), CG, and CC or C/(−); and alleles G and C at rs3764879 (p > 0.05). We found a strong association with genotype A/(−) at rs3764880 with susceptibility to pulmonary TB in males (OR 2.87, 95%CI 1.38–5.98, p = 0.007).
Conclusions: Our results provide evidence, for the first time, of a role for the TLR8 gene in susceptibility to pulmonary TB in male children. Additional research to verify our results are necessary. Tuberculosis in children presents particularly difficult challenges, but research priorities and advances in pediatric tuberculosis could provide wider insights and opportunities for tuberculosis control. 相似文献
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44.
Tuncer Demir Ibrahim Turkbeyler Davut Sinan Kaplan Yavuz Pehlivan Mustafa Orkmez Ediz Tutar Seyithan Taysi Bunyamin Kisacik Ahmet Mesut Onat Cahit Bagcı 《Inflammation》2013,36(1):75-79
Systemic sclerosis (SSc) is a disease characterized by skin and internal organ involvement. There is progressive accumulation of extracellular matrix components in the skin and involved organs. Tissue fibrosis is the prominent reason for mortality, and still, there is no satisfactory treatment. The aim of this study was to evaluate the effects of urotensin-II (U-II) antagonist palosuran in an animal model of scleroderma. We also planned to measure U-II, endothelin-1 (ET-1), and transforming growth factor-β1 (TGF-β1) levels, as well as the association of these levels with dermal thickness. Twenty-four male mice were included in this study and they were divided into three groups—group 1: control group, group 2: fibrosis group, and group 3: fibrosis + palosuran treatment group. Fibrosis + palosuran treatment in group 3 reduced ET-1, U-II, and TGF-β1 levels. In total, the diminished values were statistically significant in the ET-1 and TGF-β1 levels (p?<?0.05). Dermal thickness was higher in the fibrosis group, when compared with the other groups. There was no significant relationship between dermal thickness and ET-1, U-II, or TGF-β1 levels (p?>?0.05). It is believed that U-II is an important mediator in SSc, and its antagonism with palosuran could be a new treatment choice in SSc. 相似文献
45.
Ahmet Mesut Onat Yavuz Pehlivan Ibrahim Halil Turkbeyler Tuncer Demir Davut Sinan Kaplan Ali Osman Ceribasi Mustafa Orkmez Ediz Tutar Seyithan Taysi Mehmet Sayarlioglu Bunyamin Kisacik 《Inflammation》2013,36(2):405-412
Pulmonary arterial hypertension (PAH) is a progressive and a life-threatening disease with its high morbidity and mortality ratios. On searching for new shining targets in pathogenesis, we noticed, in our previous studies, urotensin-II (UII) in systemic sclerosis with potent angiogenic and pro-fibrotic features. Owing to the mimicking properties of UII with endothelin-1 (ET1), we attempted to investigate the effect of palosuran in a PAH rat model. Thirty rats were randomly divided into three groups, with each group comprising 10 rats: group 1 (control group) received the vehicle subcutaneously, instead of monocrotaline (MCT) and vehicle; group 2 (MCT group) received subcutaneous MCT and vehicle; and group 3 (MCT + palosuran group) received subcutaneous MCT and palosuran. Serum UII, ET1, transforming growth factor-β1 (TGF-β1) levels, pulmonary arteriolar pathology of different diameter vessels, and cardiac indices were evaluated. The ET1, TGF-β1, and UII levels were significantly diminished in the treatment group, similar to the controls (p?<?0.001). Right ventricular hypertrophy index and mean pulmonary arterial pressure scores were also significantly reduced in the treatment group (p?=?0.001). Finally, in the 50–125-μm diameter arterioles, in contrast to Groups 3 and 1, there was a statistically significant thickness (p?<?0.01) in the arteriolar walls of rats in Group 2. The treatment effect on arteries of more than 125-μm diameters was found to be valuable but not significant. Owing to its healing effect on hemodynamic, histological, and biochemical parameters of MCT-induced PAH, palosuran as an antagonist of UII might be an optional treatment alternative for PAH. 相似文献
46.
ümit Ko? Erdin? ?etinkaya Erdal B. Bostanci Ahu S. Kem?k Mesut Tez ?smail G?mceli Musa Ako?lu 《Disease markers》2013,35(5):363-367
Introduction. Gastric cancer is the second cause of cancer-related deaths worldwide. Delayed diagnosis leads to high mortality rates. Eotaxin-1 was originally discovered as an eosinophil-selective chemoattractant and may play a role in a number of chronic inflammatory diseases, cancer, and other gastrointestinal disorders. The aim of this study was to analyse diagnostic and prognostic significance of serum eotaxin-1 (s-eotaxin-1) levels in gastric cancer. Methods. Sixty gastric cancer patients and 69 healthy subjects were included into the study. S-eotaxin-1 levels were compared with clinicopathological features and outcomes in gastric cancer. Results. Serum levels of eotaxin-1 in gastric cancer patients were significantly higher than controls (74.51 ± 16.65 pg/mL versus 16.79 ± 5.52 pg/mL, respectively (P < 0.001)). The s-eotaxin-1 levels did not differ significantly with histopathological grade, tumor-node-metastasis (TNM) stage, tumor localization, lymph node metastases, positive lymph node ratio, size, perineural and perivascular invasion. So there is no relationship found between s-eotaxin-1 level and prognosis. Conclusion. S-eotaxin-1 levels may be used as an easily available biomarker for gastric cancer risk and may alert physicians for early diagnosis. Due to the limited number of patients included in this study, larger cohort studies are warranted to validate the diagnostic value of s-eotaxin-1 level in gastric cancer. 相似文献
47.
Etensel B Ozkisacik S Ozkara E Serbest YA Oztan O Yazici M Gürsoy H 《Pediatric surgery international》2007,23(3):271-275
Despite the prompt diagnosis and treatment of testicular torsion (TT), there are problems with fertility and atrophy after
testicular salvage. Dexpanthenol (Dxp) is the biologically active alcohol of pantothenic acid (PA). Dxp is converted to PA
in tissues. PA increases the content of reduced glutathione (GSH), Coenzyme A and ATP synthesis in cells. GSH and glutathione-dependent
peroxidases (GPX) are the major defense systems against oxidative stress. GPX-4 is the major antioxidant in testicular tissue.
However, the activity of GPX-4 appeared and increased only after puberty. We investigated the effect of Dxp on testicular
atrophy after TT at the 60th day. Rats were separated randomly into four groups. Group C: control group, group Td: torsion + detorsion,
group Sal: torsion + saline + detorsion, group Dxp: torsion + Dxp + detorsion. The left testis was rotated 720° for 2 h. In
group Sal, normal saline and in group Dxp, Dexpanthenol were injected intraperitonally, 30 min before detorsion. After 60 days,
the testicular weights and volumes were measured. Histopathology of the left testis was evaluated with mean seminiferous tubular
diameter (MSTD) and mean testicular biopsy score (MTBS). The left (torsed) testicular weight and volume of groups Td and Sal
were significantly lower compared to group Dxp. The MSTD and MTBS of group Td and Sal were significantly lower than group
Dxp. Contralateral testicular weight and volume of groups Td, Sal and Dxp had no significant difference compared to the control
group. Dxp significantly prevented testicular atrophy after 60 days of TT. Dxp has FDA approval, is safe, cost effective and
readily available. Its relevance for clinical trials may especially be for the problem of testicular atrophy catastrophe,
seen very frequently following testicular salvage. 相似文献
48.
49.
OBJECTIVES: Estrogen action in the brain influences many neurochemical processes. The aim of the study was to evaluate the acute effect of intranasal 17beta-estradiol on cerebral and cerebellar perfusion in postmenopausal women. METHODS: The study group included 24 healthy postmenopausal women who had been in natural menopause for at least 1 year (mean age: 47.38+/-5.9 years). We conducted an experimental, randomized, placebo-controlled, cross-over, double-blind study. Cerebral and cerebellar perfusion was measured after placebo (saline serum physiologic) or intranasal 17beta-estradiol administration by Single Photon Emission Computed Tomography (SPECT) using technetium-99m-hexamethylpropylene amine oxime (Tc99m-HMPAO). Regions of interest (ROIs) were drawn manually. Cerebral and cerebellar perfusions were calculated for each ROI using average number of counts per pixel. Semiquantitative analysis was performed in bilateral frontal, temporal, parietal and occipital lobes, thalamus, putamen, hippocampus, amygdala, caudate nuclei, cerebellar region, anterior/posterior of cingulate gyrus and pons. RESULTS: After intranasal 17beta-estradiol administration, SPECT study revealed significant increases in cerebral and cerebellar perfusion compared to placebo measurements in all studied slices (p<0.05). There was a positive correlation between serum estrogen levels after 17beta-estradiol and cerebral and cerebellar perfusion. CONCLUSIONS: Administration of single dose intranasal 17beta-estradiol increases cerebral and cerebellar perfusions in healthy postmenopausal women. 相似文献
50.
Tezer MS Tahamiler R Canakçioğlu S 《Asian Pacific journal of allergy and immunology / launched by the Allergy and Immunology Society of Thailand》2006,24(2-3):123-127
The purpose of this study was to compare the paranasal sinus mucosal thickenings, bony changes consistent with chronic sinusitis, and bony anatomic variations detected by computed tomography (CT) in chronic rhinosinusitis patients with and without allergy. Three hundred and thirty-nine patients with chronic rhinosinusitis were analyzed for their allergic status by performing skin prick test. Two hundred and thirteen patients (62.8%) had at least one positive skin prick test (allergic patients, male/female: 85/128, mean age: 29.1 +/- 1.2). One hundred and twenty-six patients (37.2%) were included in the non-allergic group (male/female: 53/73, mean age: 31 +/- 2.2). Maxillary mucosal thickening and frontal hypoplasy were significantly more common in allergic chronic rhinosinusitis patients. Moreover, pneumatized uncinate process is apparently more common in the allergic group than non-allergic group, and statistical analysis revealed marginal significance (p = 0.0535). In conclusion CT findings of allergic chronic rhinosinusitis patients are comparable to the CT findings of chronic rhinosinusitis patients without allergy. However, presence of maxillary mucosal thickening, frontal hypoplasia or pneumatized uncinate process in the CT scan of a patient with chronic rhinosinusitis could be of clinical significance, and might guide the otolaryngologist for the evaluation of the presence of allergy. 相似文献