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171.
Nakashima A  Yorioka N  Doi S  Masaki T  Ito T  Harada S 《BONE》2004,34(3):579-583
In patients with adynamic bone disease, the bone contains few osteoblasts or osteoclasts and bone turnover is slow, so the risk of fracture is increased. The decrease of bone remodeling may also decrease the capacity of bone to buffer calcium, leading to an increase of the calcium x phosphate product and an increased risk of arterial calcification. Such findings emphasize that an effective treatment for adynamic bone disease is required. The present study investigated the influence of vitamin K2 (menatetrenone) on hemodialysis patients with low serum parathyroid hormone levels by using bone metabolism markers. The subjects were 32 hemodialysis patients (19 men and 13 women) aged from 27 to 76 years with an intact parathyroid hormone (PTH) level of less than 65 pg/ml and an intact osteocalcin level below 20 ng/ml. All patients received oral menatetrenone therapy (45 mg/day) for 12 months. To obtain control data on bone metabolism markers in hemodialysis patients with normal bone turnover, we selected 50 patients who had intact PTH levels within the range that maintains relatively normal bone turnover, that is, from 120 to 250 pg/ml. The baseline levels of all bone metabolism markers were significantly lower in our patients than in the normal PTH control group. There was a significant increase of gamma-carboxyglutamate (Gla) osteocalcin, bone alkaline phosphatase (B-ALP), tartrate-resistant acid phosphatase (TRACP), and cross-linked N-terminal telopeptide of type 1 collagen (NTx) levels after vitamin K2 administration. Type 1 procollagen carboxyterminal propeptide (P1CP) and intact osteocalcin both showed a significant increase after 12 months of treatment. Although there was no significant change of the alkaline phosphatase (ALP) level during the 12 months before the start of vitamin K2 therapy, there was a significant increase of alkaline phosphatase after vitamin K2 administration. Adjusted calcium, serum phosphate, and intact PTH showed no significant changes throughout the study. These changes of bone metabolism markers suggested that vitamin K2 therapy can improve bone remodeling in hemodialysis patients with low serum PTH levels.  相似文献   
172.
OBJECTIVE: To determine the antitumor activity and toxicity of weekly hepatic arterial infusion (HAI) of 5-fluorouracil (5-FU) for liver metastases from colorectal cancer. In addition, the present study also evaluated the efficacy of second-line chemotherapy after termination of HAI. METHODS: A retrospective study was designed to evaluate the clinical outcome in patients treated with HAI. Twenty-six patients with liver metastases from colorectal cancer were treated with 5-FU 1000 mg/m(2) over 5 h once per week on an outpatient basis. The treatment was continued until disease progression, unacceptable toxicity or the patient's refusal to continue treatment occurred. One of three kinds of second-line systemic chemotherapy, irinotecan alone, protracted venous infusion of 5-FU or methotrexate (MTX) and 5-FU, was chosen after termination of HAI. RESULTS: An objective tumor response to HAI was observed in 46% (95% confidence interval, 26.9-65.2%) of 26 patients. The most common adverse events were mild nausea and vomiting (35%) and occurrence of gastroduodenal ulcers (15%). Hematological toxicity was minimal. No responder was observed to improve following second-line chemotherapy after termination of HAI. CONCLUSION: Weekly HAI of 5-FU is both active and well tolerated. However, extrahepatic progression was observed in one-third of patients with termination of HAI and the efficacy of second-line chemotherapy was not demonstrated. Regional treatment with systemic chemotherapy should be conducted to achieve good results in terms of survival.  相似文献   
173.
The present study was conducted to examine the effects of selective cyclooxygenase (COX)-2 inhibitors, nimesulide and etodolac, on early stages of tongue carcinogenesis due to 4-nitroquinoline 1-oxide(4-NQO). Fischer 344 rats, 6 weeks old, were given 15 ppm of 4-NQO in their drinking water for 8 weeks followed by diet containing either nimesulide or etodolac at the doses of 150 and 300 ppm for 16 weeks. Rats were sacrificed at 24 weeks and tongue lesions were histologically examined. Nimesulide dose-dependently reduced the incidence and multiplicity of squamous cell dysplasias and carcinomas (SCCs), with significance at the 300 ppm dose. This suppression was associated with an increased incidence and multiplicity of hyperplasias. Etodolac exhibited similar but less extensive suppressive effects. The results suggest that COX-2 is involved in the progression of hyperplasia to dysplasia and from dysplasia to SCCs.  相似文献   
174.
We have been developing a small, lightweight motor-driven pulsatile left ventricular assist device (LVAD) with a ball screw. The motor-driven LVAD consists of a brushless DC motor and a ball screw. The attractive magnetic force between Nd–Fe–B magnets (with a diameter of 5 mm and a thickness of 1.5 mm) mounted in holes in a silicone rubber sheet (thickness 2 mm) and an iron plate adhered onto the a diaphragm of the blood pump can provide optimum active blood filling during the pump filling phase. The LVAD has a stroke volume of 55 ml and an overall volume of 285 ml; it weighs 360 g. The controller mainly consists of a fuzzy logic position and velocity controller to apply doctors' and engineers' knowledge to control the LVAD. Each unit of the controller consists of a functionally independent program module for easy improvement of the controller's performance. The LVAD was evaluated in in vitro experiments using a mock circulation. A maximum pump outflow of 5.1 l/min was obtained at a drive rate of 95 bpm against an afterload of 95 mmHg, and active filling using the attractive magnetic force provided a pump output of 3.6 l/min at a drive rate of 75 bpm under a preload of 0 mmHg. The operating efficiency of the LVAD was measured at between 8% and 10.5%. While the LVAD can provide adequate pump outflow for cardiac assistance, further upgrading of the software and improvement of the blood pump are required to improve pump performance and efficiency.  相似文献   
175.
CAP18 (an 18-kDa cationic antimicrobial protein) is a granulocyte-derived protein that can bind lipopolysaccharide (LPS) and inhibit various activities of LPS in vitro. The present study examined the protective effect of a synthetic 27-amino-acid peptide (CAP18109–135) from the LPS-binding domain of CAP18 against antibiotic-induced endotoxin shock, using highly LPS-sensitive d-(+)-galactosamine (d-GalN)-sensitized C3H/HeN mice. The antibiotic-induced endotoxin (CAZ-endotoxin) was prepared from the culture filtrate of Pseudomonas aeruginosa PAO1 exposed to ceftazidime (CAZ). Injection of CAP18109–135 protected the mice injected with LPS or CAZ-endotoxin from death and lowered their tumor necrosis factor (TNF) levels in serum in a dose-dependent manner. Treatment with CAZ caused death of the d-GalN-sensitized P. aeruginosa PAO-infected mice within 48 h, while injection with CAP18109–135 rescued the mice from death. In the mice rescued from death by injection with CAP18109–135, endotoxin levels in plasma and TNF production by liver tissues were decreased but the numbers of viable infecting bacteria in their blood were not decreased significantly and remained at the levels in CAZ-treated mice. These results indicate that CAP18109–135 is capable of preventing antibiotic-induced endotoxic shock in mice with septicemia and that the effect is due to its LPS-neutralizing activity rather than to its antibacterial activity.Endotoxin, i.e., lipopolysaccharide (LPS), associated with proteins in the outer membrane of gram-negative bacteria (18), is strongly implicated in the pathogenesis of gram-negative bacterial sepsis, including fever, shock, disseminated intravascular coagulation, multiple organ failure, and death (35, 39). The septic shock induced by bacteremia due to gram-negative bacteria is thought to be due to the massive release of endotoxin from the infecting organisms by spontaneous release or bacterial lysis. The released endotoxin activates macrophages, endothelial cells, and fibroblasts to produce and release potent inflammatory mediators, including tumor necrosis factor alpha (TNF), interleukin (IL)-1β, IL-6 and nitric oxide (34). The mediators, especially TNF, cause endotoxic shock syndrome (6, 28). Endotoxic shock may occur in the process of therapy with inappropriate antibiotics. Although antibiotics kill bacteria, they do not neutralize endotoxin. Sudden release of an excess amount of endotoxin from the antibiotic-disrupted bacteria can result in endotoxic shock (22).A number of host-derived proteins, such as low-density lipoprotein, high-density lipoprotein (10), LPS-binding protein (41) and bactericidal permeability-increasing protein (9, 12, 42), can bind to endotoxin and modulate endotoxic activity negatively or positively. Lower concentrations of LPS complexed with LPS-binding protein may activate macrophages through their surface protein CD14 (41, 46). In contrast, high-density lipoprotein or bactericidal permeability-increasing protein bound to LPS inhibits the ability of LPS to elicit cellular responses (10, 30).CAP18 is an 18-kDa cationic protein capable of binding to LPS. It was isolated from rabbit granulocytes as a protein with antimicrobial, LPS-binding, and LPS-neutralizing properties and purified by using its capacity to agglutinate LPS-sensitized sheep erythrocytes (13, 16, 26). CAP18 and its C-terminal 37-amino-acid fragment inhibit the LPS-induced production of tissue factor by murine macrophages and human monocytes (13) and of TNF, IL-1β, IL-6, and nitric oxide by murine macrophages in vitro (26). The peptide has potent activity against both gram-negative and gram-positive bacteria in vitro (25). A more recent study demonstrated that treatment with a C-terminal 37-amino-acid fragment of rabbit CAP18 neutralized the deleterious effects of LPS in pigs (45). Rabbit CAP18 cDNA has been cloned (27). Based on the nucleotide sequence of the rabbit CAP18 cDNA, human CAP18 cDNA was also cloned (24). The human CAP18 cDNA encodes a protein composed of a 30-amino-acid signal peptide, a 103-amino-acid N-terminal domain of unknown function, and a 37-amino-acid C-terminal domain that binds to LPS, neutralizes LPS-mediated activation of monocytes, and reduces the lethal toxicity of LPS in mice (15, 17, 24). The C-terminal 27-amino-acid fragment was identified as the LPS-neutralizing and antimicrobial domain (15). This peptide was synthesized and was designated CAP18109–135.Recently, investigators have recognized that the use of antibiotic chemotherapy to treat infections with gram-negative microbes may result in the release of microbial constituents that might, in turn, exacerbate the pathophysiological manifestations of disease. Although the actual clinical importance of this phenomenon to patients with sepsis due to gram-negative bacteria is unclear, both in vitro and in vivo animal experiments have provided evidence in support of this concept (22, 31, 32). CAP18 may neutralize the toxicity of antibiotic-induced endotoxin in vivo and prevent death from septic shock. The present study was designed to determine the protective effect of CAP18109–135 against antibiotic-induced endotoxic shock in a murine model of Pseudomonas aeruginosa infection, and the results demonstrate that CAP18109–135 is capable of reducing the mortality of the mice due to endotoxic shock through neutralization of endotoxin and reduction of TNF production in the mice.  相似文献   
176.
BACKGROUND: We previously reported elevated levels of total serum IgE in patients with asthma, regardless of their atopic status. We hypothesized that certain factors inherent to asthma may contribute to this non-specific elevation of total serum IgE. In the current study, to evaluate the role of eosinophils in the regulation of total serum IgE, we examined whether peripheral blood eosinophil count is associated with total serum IgE level in patients with eosinophilic lung diseases. METHODS: Ninety-nine healthy controls, 277 patients with asthma, 15 patients with acute eosinophilic pneumonia, 21 patients with chronic eosinophilic pneumonia were studied for total serum IgE levels and peripheral blood eosinophil counts. RESULTS: Patients with acute or chronic eosinophilic pneumonia had significantly increased total serum IgE levels compared with healthy controls regardless as atopic status (p<0.001). In non-atopic subjects with eosinophilic lung diseases, total serum IgE level was significantly correlated with peripheral blood eosinophil count (r=0.42, p<0.001, n=57). CONCLUSION: Our findings suggest that, in addition to antigen-specific IgE production, non-specific IgE production may contribute to elevated levels of total serum IgE in patients with asthma or eosinophilic pneumonia. An increased number of activated eosinophils may underlie an increased total serum IgE level in these conditions.  相似文献   
177.
178.
gamma-Interferon (IFN-gamma) is known to induce expression of major histocompatibility complex (MHC) class II antigens on murine astrocytes and MHC class I antigens on murine oligodendrocytes. We studied whether the human IFN-gamma could induce the expression of Human Leukocyte Antigen (HLA)-A, B, C and -DR antigens on cultured human glia from autopsied brain white matter tissue. HLA-A, B, C antigens were induced on both human astrocytes and oligodendrocytes, whereas HLA-DR antigens were induced only on some astrocytes. From these results, it is suggested that IFN-gamma affects the expression of MHC class I and class II antigens on astrocytes and oligodendrocytes derived from human brain. The relationship between the induction of MHC class I and class II antigens by IFN-gamma and the pathogenesis of multiple sclerosis is discussed.  相似文献   
179.
The tissue distribution of Klebsiella pneumoniae O3 lipopolysaccharide (KO3 LPS) was studied in mice injected subcutaneously (s.c.) or intraperitoneally (i.p.) with 125I-labeled KO3 LPS. Marked retention of KO3 LPS radioactivity could be found at the site of s.c. injection for several weeks. On the other hand, about 85% of the radioactivity rapidly disappeared from the peritoneal cavity within 6 h after i.p. injection. The long-term presence of KO3 LPS at the injection site was also supported by experiments with 51Cr-labeled KO3 LPS and immunoblotting and immunofluorescence staining methods. The R-form LPS lacking the O-specific polysaccharide chain of KO3 LPS and the lipid A fraction of KO3 LPS seemed to remain at the site in larger amounts and for longer times than KO3 LPS. There were no marked differences in the retention pattern at the injection site among KO3 LPS, Escherichia coli LPS, Salmonella typhosa LPS, and Salmonella enteritidis LPS. However, much less radioactivity accumulated in the livers and spleens of mice injected with either KO3 LPS or S. typhosa LPS compared with the other LPS preparations. It was suggested that retention of LPS at the site of s.c. injection may play an important role in the development of various biological actions of s.c. injected LPS.  相似文献   
180.
Lipopolysaccharide from Klebsiella pneumoniae O3, which possesses the mannose homopolysaccharide as the O-specific polysaccharide, exhibits an extraordinarily high ability to activate the human complement system. We isolated the mannose-binding protein with a Klebsiella O3 lipopolysaccharide affinity column. The protein isolated had a molecular mass of much higher than 200 kDa, and it consisted of subunits with an apparent molecular mass of 32 kDa. The NH2-terminal sequence of the 32-kDa subunits was completely consistent with a part of the amino acid sequence of human serum mannose-binding protein. In immunoblotting, an anti-mannose-binding protein monoclonal antibody was definitely reactive with the isolated protein with the higher molecular mass. The protein isolated was bound exclusively to lipopolysaccharides possessing the mannose homopolysaccharide, not to lipopolysaccharide possessing the heteropolysaccharides. Klebsiella O3 lipopolysaccharide did not exhibit a high anticomplement activity in the serum from which the mannose-binding protein was depleted. It was concluded that the serum factor that bound to Klebsiella O3 lipopolysaccharide may be mannose-binding protein and that it may play a crucial role in the strong complement activation by Klebsiella O3 lipopolysaccharide.  相似文献   
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