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61.
OBJECTIVE: The aims of this study were to clarify changes in total ghrelin within the somatotropic axis in severe burn subjects with or without inhalation injury as well as the responsiveness of GH, IGF-1, and IGFBP-3 to the different severity of burn injuries. DESIGN: Twenty-three patients with severe burn injuries (>30% of 2nd degree burns or >10% of 3rd degree burns) were classified into 2 groups according to inhalation injury: group I with inhalation injury (n=9) and group II without inhalation injury (n=14). The evaluations of serum GH, IGF-1, IGFBP-3, and total ghrelin were done on post-burn injury days 3, 7, 14, 21, and 40. Cortisol levels were measured from 24-h urine collections on post-burn injury days 7 and 21. RESULTS: In all subjects, the levels of GH fluctuated throughout the observation period whereas IGF-1 showed an initial decline with nadir on day 7 and a subsequent increase through day 40. The levels of IGFBP-3 and total ghrelin showed a progressive increase with nadir on day 3. Compared with the group II, the GH levels were increased in the group I on post-burn days 3, 7, and 14, of which day 7 showed statistical significance (p<0.05). The levels of IGF-1 (days 7 and 21; p<0.05) and IGFBP-3 (days 7, 14, 21, and 40; p<0.05, p<0.01, p<0.05, p<0.05, respectively) were lower in the group I than in the group II throughout the study period. On post-burn injury days 3, 7, 14, and 21, total ghrelin levels were lower in the group I than in the group II with statistical significance on post-burn day 7 (p<0.001). CONCLUSIONS: Our present data show a concurrence of elevated GH levels and decreased IGF-I, IGFBP-3, and total ghrelin levels during the early burn injury period, in addition to more GH burst amplitude as well as greater falling of IGF-I, IGFBP-3 and total ghrelin levels proportional to the severity of burn injury. Further studies are needed to ascertain whether acyl- and desacyl-ghrelin instead of total ghrelin are completely independent of increased GH or other stress mediators, and whether GH-releasing hormone (GHRH) mainly stimulates the production and release of GH in acute critical conditions.  相似文献   
62.
A novel device is described that generates an ultrasonic force field in a fluid layer. The force field arises because of the acoustic radiation force, a second order effect, generated as an ultrasonic wave interacts with a suspended particle. This force field can be used to manipulate objects in the fluid layer trapped between this device and an arbitrary surface, in this case, a flat object slide. The device is shown to be capable of positioning and, in doing so, concentrating human cells to predictable locations. Mesenchymal and HeLa cells were used. Critically, the forces required to do this can be generated by ultrasonic pressure fields that do not affect the viability of the cells. The viability has been assessed using trypan blue dye. The device used consists of a 14 mm square glass plate that is excited by at least one of four piezotransducers attached to the edges. The resulting ultrasonic force field and, importantly, the location of the minima in the force potential at which the cells are collected, has been calculated analytically.  相似文献   
63.
In order to investigate the status of some circulating factors in nephrotic syndrome, we examined the secretion of monocyte chemotactic peptide (MCP)-1, tumor necrosis factor (TNF) alpha or fibronectin in sera or by peripheral blood mononuclear cells (PBMC) from patients with membranous nephropathy (MN), diabetic nephropathy (DN) or minimal change disease (MCD). Also the effects of PBMC or sera on human mesangial cells (MC) were evaluated. Serum TNF alpha levels were higher in patients with MN than in controls, but PBMC exhibited no differences in TNF alpha production between patients and controls. Serum fibronectin levels were higher in patients with MN than in controls. PBMC from diabetic patients with or without nephropathy produced more MCP-1 than cells from controls. When MC were cultured with PBMC supernatants from patients, TNF alpha levels in PBMC supernatants correlated with production of MCP-1 or fibronectin by MC. PBMC supernatants obtained from patients with MCD and MN decreased MCP-1 production by MC, but did not affect thymidine incorporation or fibronectin production by MC. Sera obtained from patients with DN and MCD reduced thymidine incorporation in MC. In summary, serum TNF alpha or fibronectin levels were increased in patients with MN that is known to progress to renal failure. MCP-1 Production was increased by PBMC obtained from diabetic patients with or without nephropathy. Also TNF alpha production by PBMC in individual patients may affect the pathophysiology of their MC.  相似文献   
64.
This multicenter, phase 4, Prospective Randomized Open, Blinded End‐point (PROBE) study aimed to evaluate safety and efficacy of telmisartan/rosuvastatin single‐pill combination (SPC) therapy on lowering central blood pressure (BP) compared with telmisartan monotherapy in hypertensive patients with dyslipidemia in Korea. Study was terminated earlier than planned due to COVID‐19 pandemic, thus should be considered as a pilot study. Among 125 patients who met the inclusion criteria of hypertension and dyslipidemia (defined as 10‐year Atherosclerotic Cardiovascular Disease risk score over 5%), 80 patients went through 4‐week single‐group run‐in period with telmisartan 40–80 mg, then randomized to telmisartan 80 mg + rosuvastatin (10 or 20 mg) SPC group or telmisartan 80 mg monotherapy group. The central/brachial BP, brachial‐ankle pulse wave velocity (baPWV), and augmentation index (AIx) were assessed at baseline and 16 weeks later. Mean brachial SBP changed from 135.80 ± 14.22 mmHg to 130.69 ± 13.23 mmHg in telmisartan/rosuvastatin group and from 134.37 ± 12.50 mmHg to 133.75 ± 12.30 mmHg in telmisartan monotherapy group without significant difference (between‐group difference = .149). Mean central SBP were reduced significantly in the telmisartan/rosuvastatin group with change from 126.72 ± 14.44 mmHg to 121.56 ± 14.56 mmHg while telmisartan monotherapy group showed no significant change (between‐group difference = .028). BaPWV changed from 1672.57 ± 371.72 m/s to 1591.75 ± 272.16 m/s in telmisartan/rosuvastatin group and from 1542.85 ± 263.70 m/s to 1586.12 ± 297.45 m/s in telmisartan group with no significance (between‐group difference = .078). Change of AIx had no significant difference (between‐group difference = .314). Both groups showed excellent compliance rate of 96.9 ± 4.5% with no significant difference in adverse rate. Telmisartan/rosuvastatin SPC therapy was more effective in lowering central BP compared with the telmisartan monotherapy. The results of this study showed benefit of additive statin therapy in hypertensive patients combined with dyslipidemia.  相似文献   
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67.
A high pressure liquid chromatographic system (HPLC) has recently been developed for the simultaneous detection of malondialdehyde (MDA), formaldehyde (FA), acetaldehyde (ACT) and acetone (ACON). We have examined the urinary excretion of these four lipid metabolites in the urine of rats following the acute oral administration of MDA (158 mg/kg body weight). During the first 12 h, increases in the urinary excretion of MDA and ACT of approximately 192- and 70-fold, respectively, were observed. The urinary excretion of both MDA and ACT decreased thereafter. An increase in FA excretion was observed only 12–24 h after MDA administration. A significant decrease in ACON relative to control values was observed 12–48 h after MDA treatment. Two new peaks were present in the HPLC chromatograms of urine samples 0–24 h after MDA administration. Both peaks were shown to be due to methyl ethyl ketone (MEK) which appears to be formed as a result of MDA metabolism. The results demonstrate that orally administered MDA is rapidly excreted in the urine, and alters the metabolism and excretion of other lipid metabolites.  相似文献   
68.
We explored poly(4-vinylimidazole) (P4V) as a nonviral gene carrier. We show that P4V can form DNA condensates of small size (<110 nm) using a dye-exclusion assay with ethidium bromide and dynamic light scattering, and that the complexes form in a pH-sensitive manner, due to the amphotericity of the polymer. P4V was demonstrated to lead to transfection in vitro as effectively as polyethyleneimine (PEI), but at lower cytotoxicity, under conditions where higher amounts of either polymer are required, using luciferase and green fluorescent protein as examples. Transfection in vivo was also explored, using a gene encoding yellow fluorescent protein and human osteoprotegerin injected in the tail vein of the rat. Transfection was observed, both at the gene and protein levels in lung and spleen tissue. Transfection in vivo appeared to be at least as effective using P4V as with PEI. Based upon this good transfection and low cytotoxicity, P4V seems to show promise as a nonviral gene transfer vector.  相似文献   
69.
A ductographical and histological study was carried out in 70 human pancreata postmortem. The diameter, the thickness and the length of the major pancreatic duct were measured. The obtained data were evaluated statistically. The autopsy revealed in 7 cases an acute or a mild chronic pancreatitis, in 20 cases a disease of the bile duct system, in 4 both an acute pancreatitis and a bile duct disease, while the other patients showed no inflammatory or neoplastic diseases of the pancreas or the bile ducts. The relative wall thickness of the duct increases with growing distance from the papilla, while the real thickness of the wall decreases. The inner and outer diameter of the duct steadily rises with aging. The relative thickness decreases with aging, but in a considerable less degree. The length of the duct growths with aging. All these relations were expressed in mathematical equations. In acute pancreatitis, in mild chronic pancreatitis and in disease of the bile duct system no statistically significant differences of the outer and inner diameter, of the length and the relatative thickness of the wall were found in comparison to normal pancreata.  相似文献   
70.
Parathyroid cysts: diagnosis and management   总被引:3,自引:0,他引:3  
  相似文献   
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