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81.
82.
The objective of this study was to examine the effects of polyphenolic compounds, present in noncommercially available green tea, on hair loss among rodents. In an experimental study, we randomly assigned 60 female Balb/black mice, which had developed spontaneous hair loss on the head, neck and dorsal areas into two equal groups; A (experimental) and B (control). Group A received 50% fraction of polyphenol extract from dehydrated green tea in their drinking water for six months. Group B received regular drinking water. Both groups were fed regular rodent diets (Purina Rodent Chow 5001) and housed individually in polycarbonate cages. The results showed that 33% of the mice in experimental Group A, who received polyphenol extract in their drinking water, had significant hair regrowth during six months of treatment (p = 0.014). No hair growth was observed among mice in the control group, which received regular water.  相似文献   
83.
Sarcoidosis involves the spleen in a significant percentage of patients afflicted with this disease. The most commonly applied modality for studying such patients is the 99mTc-sulfur colloid scan. Different patterns have been recognized: “normal” spleen and nonspecific splenic enlargement, with or without focal areas of photon deficiency, which was thought to represent an infarction in a previous report. We have encountered two patients showing splenomegaly and multifocal photon deficiencies secondary to sarcoid granulomata. These cases are presented to inform clinicians of a new pattern. Our patients were managed with systemic corticosteroids and palliation of pain. If symptoms persist or worsen, splenectomy may be necessary to avoid spontaneous rupture. An abbreviated differential diagnosis of the enlarged spleen with multiple focal defects is discussed.  相似文献   
84.
OBJECTIVE: To examine results of semen culture in a population of infertile men with asymptomatic leukocytospermia, and to determine the correlation between culture results and sperm characteristics in these patients. METHODS: Semen samples were collected from a group of infertile men (n = 80) after 2-3 days of sexual abstinence. Standard semen analysis was performed according to World Health Organization (WHO) guidelines. Seminal leukocyte concentrations were determined by a myeloperoxidase staining technique. Culture of semen was performed on enriched and specific culture media. RESULTS: Based on the results of semen culture, the samples were classified into three groups: group 1 (enteric gram-negative bacilli [Enterobacteriaceae], n = 13), group 2 (bacteria other than Enterobacteriaceae, n = 15), and group 3 (negative cultures, n = 52). No correlation was found between positive semen culture and sperm characteristics (concentration, motility, and morphology). However, seminal leukocyte concentrations were negatively correlated with percentages of motile sperm and normal sperm morphology. CONCLUSION: Our data indicate that semen samples from infertile men with asymptomatic leukocytospermia may have bacterial contamination, evidenced by positive bacterial cultures. Lack of correlation between positive semen cultures and sperm characteristics may be indicative of early or mild (subclinical) infection.  相似文献   
85.
The characterization of several seven-transmembrane G protein-coupled receptors, which function as coreceptors for HIV-1, HIV-2, and/or SIV, has opened up a whole new area of AIDS research. Animal models that have played a central role in the understanding of lentivirus pathogenesis and the design of novel vaccine strategies may also be invaluable in studying the role of these secondary receptors in infection and disease progression. However, since it is known that minor species-specific sequence changes in CCR3 and STRL33 affect their ability to act as coreceptors for HIV-1, HIV-2, and/or SIV, it is important to ascertain whether the relevant receptors function as expected in the animal model of choice. Many studies have been performed on the function of rhesus macaque receptors, but not on the cynomolgus macaque equivalents. Both species are used as animal models for lentivirus pathogenesis, but since there are differences in their susceptibility to viral infection, we felt it was important for information to be available for both rhesus and cynomolgus macaque receptors. The sequence of three cynomolgus macaque receptors, CCR3, GPR15, and STRL33, are presented in this sequence note. These sequences are compared with already published human and rhesus macaque homologs. Functional studies are currently being performed on these three cynomolgus macaque receptors to determine their ability to function as coreceptors for HIV-2, SIV, and/or SHIV isolates.  相似文献   
86.
Objective To describe a novel technique of using the CO2 laser for a revision pedicled nasoseptal flap (PNSF) takedown.Patient Patient with a pituitary adenoma recurrence that had undergone an endoscopic skull base resection with a nasoseptal flap repair 3 years prior.Procedure Flap edges and bony defect are examined using an image-guidance probe to identify the full extent of the defect. The CO2 laser fiber is used to incise through to the underlying skull base. The flap is then elevated from its most distal portion toward the pedicle, using the laser to cut adhesions away from the underlying dura. The skull base defect is then repaired with an onlay graft of acellular dermis, then the PNSF.Results The laser was adept at dissecting through mucosa to the underlying bone and at dissecting the underside of the flap from the posterior adhesions and intradural structures safely.Conclusion The novel use of the of the CO2 laser for the flap takedown was very effective at safely making the mucosal cuts and dissecting the flap from the underlying structures. The nasoseptal flap takedown can be a technically challenging procedure that was made easier by the use of the CO2 laser.  相似文献   
87.
The luteinizing hormone/chorionic gonadotropin receptor (LHCGR) belongs to the family of G-protein coupled receptors and binds both luteinizing hormone (LH) and human chorionic gonadotropin (hCG). Ligand-receptor interaction mediates a downstream cascade of events which is essential for ovulation in women, and expression of the male phenotype in men. The human LHCGR gene consists of 11exons and 10 introns. Homozygous and compound heterozygous mutations may inactivate the receptor by altering its structure and subsequent function. Herein we reported a novel, compound heterozgygous inactivating LHCGR mutation in a woman who presented with secondary infertility, having previously carried to term a donor oocyte pregnancy. A 27 bp deletion was detected in exon I at amino acid number 12. This mutation involved the signal peptide region, which is important for protein targeting, maturation and cellular expression. Another mutation involving a 2 base pair (thymine and cytosine) deletion was detected in exon 11 at amino acid number 586. This deletion produced a frameshift resulting in a premature stop codon and a truncated protein. An XY sibling with the same mutations was phenotypically female and misdiagnosed as complete androgen insensitivity syndrome. Other unaffected family members were genetically tested and carried one of the two mutations.  相似文献   
88.
This review is a journey of the landmark erythroblast macrophage protein (Emp) discovered in 1994, and it walks chronologically through the progress that has been made in understanding the biological function of this protein. Historically, Emp was the first identified cell attachment molecule and is expressed in both erythroblasts and macrophages and mediates their attachments to form erythroblastic islands. The absence of Emp erythroblasts shows defects in differentiation and enucleation. Emp‐deficient macrophages display immature morphology characterized by small sizes, round shapes, and the lack of cytoplasmic projections. Although the primary sequence of Emp has already been determined and its role in both erythroid and macrophage development is well established, there are major gaps in the understanding of its function at the molecular level. Recent studies had implicated its importance in actin cytoskeleton remodeling and cell migration, but the molecular mechanisms are still enigmatic. Previous studies have also demonstrated that downregulation of Emp affects the expression of mitogen‐associated protein kinase 1 (MAPK1) and thymoma viral protooncogene (AKT‐1) resulting in abnormal cell motility. In this review, we summarize the proposed function of Emp based on previous studies, present scenarios, and its plausible future in translational research.  相似文献   
89.
Skeletal muscle contains intramyocellular lipid droplets within the cytoplasm of myocytes as well as intermuscular adipocytes. These depots exhibit physiological and pathological variation which has been revealed with the advent of diagnostic imaging approaches: magnetic resonance (MR) imaging, MR spectroscopy and computed tomography (CT). CT uses computer‐processed X‐rays and is now being applied in muscle physiology research. The purpose of this review is to present CT methodologies and summarize factors that influence muscle radiation attenuation, a parameter which is inversely related to muscle fat content. Pre‐defined radiation attenuation ranges are used to demarcate intermuscular adipose tissue [from ?190 to ?30 Hounsfield units (HU)] and muscle (?29 HU to +150 HU). Within the latter range, the mean muscle radiation attenuation [muscle (radio) density] is reported. Inconsistent criteria for the upper and lower HU cut‐offs used to characterize muscle attenuation limit comparisons between investigations. This area of research would benefit from standardized criteria for reporting muscle attenuation. Available evidence suggests that muscle attenuation is plastic with physiological variation induced by the process of ageing, as well as by aerobic training, which probably reflects accumulation of lipids to fuel aerobic work. Pathological variation in muscle attenuation reflects excess fat deposition in the tissue and is observed in people with obesity, diabetes type II, myositis, osteoarthritis, spinal stenosis and cancer. A poor prognosis and different types of morbidity are predicted by the presence of reduced mean muscle attenuation values in patients with these conditions; however, the biological features of muscle with these characteristics require further investigation.  相似文献   
90.
The objective of this study was to determine the effects of low-level laser light exposure on the motility of spermatozoa and on DNA damage. Thirty-three semen samples were collected for routine analysis and were classified as normospermic, oligospermic, or asthenospermic. After routine semen analysis was performed, residual semen was divided into treated and control aliquots. Treated samples were exposed to a 30-second infrared laser pulse of 50 mW/cm(2) at 905 nm, a wavelength thought to increase light-sensitive cytochrome c oxidase in the mitochondrial electron transport chain. Samples were then incubated at 37°C, and aliquots were analyzed at 30 minutes and 2 hours using computerassisted semen analysis. After incubation, 250 μL of each sample was frozen at 280°C until DNA fragmentation analysis by flow cytometry. A significant increase in motility, most prominent in oligospermic and asthenospermic samples (85% increase), was observed 30 minutes after the treatment (P < .0001). No significant increase in DNA damage compared with control samples was observed. Significant changes in sperm motion kinetics were observed. Low-level laser light exposure appears to have a positive short-term effect on the motility of treated spermatozoa and did not cause any increase in DNA damage measured at 2 hours. We conclude that some cases of asthenospermia may be related to mitochondrial dysfunction. The implications of this study in terms of future clinical applications needs further investigation.  相似文献   
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