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51.
M Nemer D G Wilkinson E C Travaglini E J Sternberg T R Butt 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(15):4992-4994
The metallothioneins (MTs) constitute a diverse family of proteins, which are enriched in cysteines and bind heavy metals. The amino acid sequence of sea urchin MT has been obtained from its mRNA sequence and compared with MT sequences of various sources. A largely conserved sequence of 10 amino acids, the "central segment," is located near the center of the MT molecules of Neurospora, yeast, and Drosophila and the center of putative domains in mammalian and sea urchin MTs. The sea urchin carboxyl-terminal-half MT resembles the mammalian 9-cysteine amino-terminal MT domain I, both in the presence of this central segment and in the relative placement of cysteine residues. Conversely, the sea urchin amino-terminal-half MT, containing 11 cysteines, resembles the mammalian carboxyl-terminal MT domain II in its exclusive enrichment in vicinal cysteines. The reversed order of these sea urchin and mammalian MT halves appears to be just one aspect of a diversity based on the elaboration of structures containing the central segment. Still another variation in this diversity is the duplication of the central segment, apparent in Drosophila and crab MTs. 相似文献
52.
Ahsan Azhar Angelique N. Wong Agustina A. Cerana Vishidha R. Balankari Madhuri Adabala Diane D. Liu Janet L. Williams Eduardo Bruera 《Journal of pain and symptom management》2018,55(5):1327-1334
Context
There is limited literature regarding outpatient palliative care and factors associated with unscheduled clinic visits.Objectives
To compare characteristics of patients with unscheduled vs. scheduled outpatient palliative care clinic visits.Methods
Medical records of 183 unscheduled cancer new outpatients and 104 unscheduled follow-up (FU) patients were compared with random samples of 361 and 314 scheduled new patients and FU patients, respectively. We gathered data on demographics, symptoms, daily opioid usage, and performance status.Results
Compared with scheduled new patients, unscheduled new patients had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P = 0.002), nausea (P = 0.016), depression (P = 0.003), anxiety (P = 0.038), drowsiness (P = 0.002), sleep (P < 0.001), and overall feeling of well-being (P = 0.001); had a higher morphine equivalent daily dose of opioids (median of 45 mg for unscheduled vs. 30 mg for scheduled; P < 0.001); and were more likely to be from outside the greater Houston area (P < 0.001). Most unscheduled and scheduled new and FU visits were for uncontrolled physical symptoms. Unscheduled FU patients, compared with scheduled FU patients, had worse Edmonton Symptom Assessment Scale subscores for pain (P < 0.001), fatigue (P < 0.001), depression (P = 0.002), anxiety (P = 0.004), drowsiness (P = 0.010), appetite (P = 0.023), sleep (P = 0.022), overall feeling of well-being (P < 0.001), and higher morphine equivalent daily dose of opioid (median of 58 mg for unscheduled FU visits vs. 40 mg for scheduled FU visits; P = 0.054).Conclusion
Unscheduled new FU patients have higher levels of physical and psychosocial distress and higher opioid intake. Outpatient palliative care centers should consider providing opportunities for walk-in visits for timely management and close monitoring of such patients. 相似文献53.
The transport of cholesterol to the inner mitochondrial membrane, a key step in steroidogenesis, is subject to hormonal modulation that, at least in part, could be mediated by protein phosphorylation. This step is stimulated by sterol carrier protein 2 (SCP2) and Ca2+. To explore whether SCP2 itself is a potential control point for regulation by Ca2+-dependent phosphorylation we investigated whether highly purified SCP2 could serve as a substrate for major type Ca2+ and non-Ca2+-dependent protein kinases. Phosphorylation by calmodulin protein kinase II (CaM-PK II), myosin light chain kinase (MLCK), cAMP-dependent kinase (PKA) and protein kinase C (PKC) was monitored under optimal conditions for each enzyme. PKA, CaM-PK II and MLCK catalyzed the radiolabeling of histone 2A, synapsin I and myosin light chain (MLC), known substrates for these kinases, respectively, yet no phosphate transfer to SCP2 was observed. In contrast, PKC from two different sources (rat and calf brain) effectively catalyzed the phosphorylation of the highly purified SCP2. The phosphorylation of SCP2 depended on the addition of Ca2+ and phospholipids and was completely blocked by Polymyxin B, a PKC inhibitor. PKC catalyzed phosphorylation of SCP2 displayed a similar dependence on the concentration of ATP. Lineweaver Burk plots of the data indicate Km values for ATP of approximately 6 microM for the phosphorylation of SCP2. Our results, which have revealed for the first time that SCP2 is a substrate for PKC, are consistent with the possibilities that the control of steroidogenesis by tropic hormones and by PKC activation are mediated, at least in part, by the phosphorylation/dephosphorylation of SCP2. 相似文献
54.
Mycobacterium fortuitum is classified as a rapidly growing mycobacterium (RGM) according to the Runyon classification. RGM are increasingly being recognized as human pathogens. Joint infection due to M. fortuitum is a rare, but serious disease. This report describes a patient with acquired immunodeficiency syndrome (AIDS) and septic arthritis of the knee due to M. fortuitum in a previously normal joint with no history of surgery or intra-articular injections. 相似文献
55.
The objective of this study was to investigate changes in luteal cell cholesterol biosynthetic capacity, cholesterol accumulation, lipoprotein receptor activity, and in vivo steroidogenesis during pregnancy. Cholesterol biosynthetic capacity was assessed by measuring both the activity and the content of the rate-limiting enzyme 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase and by monitoring [14C]acetate incorporation into luteal sterols. The results showed that HMG-CoA reductase activity increased steadily during the first few days of pregnancy and reached a peak value on day 10. Subsequently, enzyme activity dropped precipitously and remained low until parturition. A parallel decline in the rate of conversion of 14C-labeled sterols was observed. Such changes in HMG-CoA reductase activity were not related to the phosphorylation/dephosphorylation state of the enzyme, but were due to a reduction in the amount of enzyme protein, as determined by the immunoblotting technique. Despite the highly active HMG-CoA reductase in the first half of pregnancy, very little cholesterol ester was stored, and serum progesterone concentrations were only about 50-75 ng/ml. However, from midpregnancy, the corpus luteum became capable of storing more cholesterol ester and producing more progesterone at a time when its ability to synthesize cholesterol declined. At this stage, luteal cells appear to shut off de novo synthesis and use principally exogenous cholesterol. To find out whether this is due to an increase in the number of high density lipoprotein (HDL) receptors, HDL-binding activity was determined in luteal cells throughout pregnancy. Whereas the Kd and the number of binding sites per mg protein were similar between days 6-18, the total content of HDL receptor increased markedly with the size of the corpus luteum. In summary, the present investigation indicates that pregnancy profoundly influences the ability of the corpus luteum to acquire, synthesize, and process the cholesterol substrate needed for steroidogenesis. 相似文献
56.
Asimina Dominari Donald Hathaway III Abdulhusein Kapasi Trissa Paul Sarabjot Singh Makkar Valeria Castaneda Sirisha Gara Bishnu Mohan Singh Kuchalambal Agadi Maliha Butt Varadha Retnakumar Spandana Chittajallu Rahima Taugir Muhammad Khawar Sana Manish KC Sarah Razzack Niala Moallem Alina Alvarez Michael Talalaev 《World Journal of Virology》2021,10(2):34-52
N-acetylcysteine (NAC) is an abundantly available antioxidant with a wide range of antidotal properties currently best studied for its use in treating acetaminophen overdose. It has a robustly established safety profile with easily tolerated side effects and presents the Food and Drug Administration's approval for use in treating acetaminophen overdose patients. It has been proven efficacious in off-label uses, such as in respiratory diseases, heart disease, cancer, human immunodeficiency virus infection, and seasonal influenza. Clinical trials have recently shown that NAC's capacity to replenish glutathione stores may significantly improve coronavirus disease 2019 (COVID-19) outcomes, especially in high risk individuals. Interestingly, individuals with glucose 6-phosphate dehydrogenase deficiency have been shown to experience even greater benefit. The same study has concluded that NAC's ability to mitigate the impact of the cytokine storm and prevent elevation of liver enzymes, C-reactive protein, and ferritin is associated with higher success rates weaning from the ventilator and return to normal function in COVID-19 patients. Considering the background knowledge of biochemistry, current uses of NAC in clinical practice, and newly acquired evidence on its potential efficacy against COVID-19, it is worthwhile to investigate further whether this agent can be used as a treatment or adjuvant for COVID-19. 相似文献
57.
Subramaniam Puvaneswary Hanumantha Rao Balaji Raghavendran Nurul Syuhada Ibrahim Malliga Raman Murali Azhar Mahmood Merican T. Kamarul 《International journal of medical sciences》2013,10(12):1608-1614
The objective of this study was to compare the morphological and chemical composition of bone graft (BG) and coral graft (CG) as well as their osteogenic differentiation potential using rabbit mesenchymal stem cells (rMSCs) in vitro. SEM analysis of BG and CG revealed that the pores in these grafts were interconnected, and their micro-CT confirmed pore sizes in the range of 107-315 µm and 103-514 µm with a total porosity of 92% and 94%, respectively. EDS analysis indicated that the level of calcium in CG was relatively higher than that in BG. FTIR of BG and CG confirmed the presence of functional groups corresponding to carbonyl, aromatic, alkyl, and alkane groups. XRD results revealed that the phase content of the inorganic layer comprised highly crystalline form of calcium carbonate and carbon. Atomic force microscopy analysis showed CG had better surface roughness compared to BG. In addition, significantly higher levels of osteogenic differentiation markers, namely, alkaline phosphatase (ALP), Osteocalcin (OC) levels, and Osteonectin and Runx2, Integrin gene expression were detected in the CG cultures, when compared with those in the BG cultures. In conclusion, our results demonstrate that the osteogenic differentiation of rMSCs is relatively superior in coral graft than in bone graft culture system. 相似文献
58.
Azhar A. Khan Aadithya B. Urs Jeyaseelan Augustine Hanspal Singh 《The Journal of forensic odonto-stomatology》2020,38(3):35
The grinding of a whole tooth specimen has been considered the conventional method to extract genomic deoxyribonucleic acid (DNA) in forensic science. However, we have tried the less destructive reverse root canal filing (RRCF) method without disturbing the morphology of the tooth to achieve competent amplifiable DNA. A total of 27 pairs of bilateral intact extracted teeth from the same subject were used in three different simulated environmental conditions for the respective RRCF and conventional methods: (a) soil burial for six months, (b) incineration at 200º C for four minutes, and (c) immersion in water for two months. Qualitative agarose gel electrophoresis assessment and downstream amplification were performed. The results showed significantly higher mean DNA concentration for the RRCF method in all three environmental conditions (p value = 0.008) in comparison to the conventional method. However, comparable qualitative results were found in both methods for the mean DNA concentration for incinerated (159.49 ng/ml), soil (119.52 ng/ml), and water (108.60 ng/ml) samples. It was concluded that the RRCF method is better quantitively (ng/ml) and comparable in terms of quality with respect to the conventional method, with the added advantage of preservation of the tooth morphology. 相似文献
59.
A novel technique using three‐dimensionally documented biopsy mapping allows precise re‐visiting of prostate cancer foci with serial surveillance of cell cycle progression gene panel
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60.