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排序方式: 共有802条查询结果,搜索用时 15 毫秒
791.
Abstract Medical records of 18 patients with spontaneous bacterial peritonitis (SBP) and 19 patients with culture negative neutrocytic ascites (CNNA) were reviewed. The diagnosis of SBP was based on a positive ascitic fluid culture, a polymorphonuclear cell count (PMN) greater than 250 cells/mm3 and the absence of an intra-abdominal source of infection. The diagnosis of CNNA was based on a PMN count greater than 250 cells/mm3, a negative ascitic fluid culture, the absence of an intra-abdominal source of infection and no antibiotic treatment in the preceding 30 days. All patients in both groups had liver cirrhosis, which was mainly (62.2%) due to HBV infection. A single strain, mostly 'a Gram-negative' bacillus, was recovered from the ascitic fluid culture in the vast majority of patients (83%) with SBP. There were no significant differences between the clinical data of both groups. However, the CNNA group had a significantly better Pugh score ( P value = 0.01) with a mean score of 9.42 ±2.24, compared to the SBP group (10.94 ±2.88). The only significant difference in the laboratory data was that the total bilirubin was higher in the SBP group ( P 0.01). Hospital mortality was significantly higher in the SBP patients compared to those with CNNA, 50 and 16%, respectively ( P 0.03). Recurrent ascitic fluid infection occurred in one of five patients who initially presented. In contrast no recurrence was documented in 12 patients with CNNA.
Spontaneous bacterial peritonitis is a serious complication of liver cirrhosis with significantly higher mortality than CNNA. A single organism, usually enteric, is the most common causative agent.  相似文献   
792.
Ely  P; Wallace  PK; Givan  AL; Graziano  RF; Guyre  PM; Fanger  MW 《Blood》1996,87(9):3813-3821
To show that macrophages can be effectively targeted against malignant B cells, bispecific antibodies (BsAb) were constructed from two antibodies having specificity for the high-affinity Fc receptor for IgG (Fc gamma RI/CD64) and the B-cell differentiation antigens CD19 and CD37. Using a flow cytometry-based assay and confocal imaging, we show that these constructs mediated significant phagocytosis of B lymphocytes by macrophages that could be enhanced with interferon gamma (IFN gamma) and IFN gamma in combination with macrophage colony- stimulating factor. BsAb-dependent phagocytosis was triggered through Fc gamma RI and could be blocked only by using F(ab')2 fragments from the parent molecule or by cross-linking Fc gamma RI. BsAb-dependent phagocytosis was not blocked by antibodies to the other Fc receptors, Fc gamma RII and Fc gamma RIII. Because these antibody constructs bind to an epitope outside the Fc gamma RI ligand binding site, we show that autologous serum, polyclonal IgG, and monomeric IgG1 did not block BsAb- dependent phagocytosis, whereas autologous serum and the IgG fractions blocked parent molecule monoclonal antibody-dependent phagocytosis due to the avid binding of monomeric IgG to Fc gamma RI. Finally, BsAb- mediated phagocytosis was effective against the malignant B cells of patients with mantle cell lymphoma, prolymphocytic leukemia, and chronic lymphocytic leukemia. Based on these studies, we propose that BsAbs may provide an effective means of immunomodulation for patients with B-cell malignancies.  相似文献   
793.
Damen  JE; Mui  AL; Puil  L; Pawson  T; Krystal  G 《Blood》1993,81(12):3204-3210
The erythropoietin receptor (EpR) belongs to a family of hematopoietin receptors whose members lack tyrosine kinase activity. Nonetheless, within minutes of binding Ep, a number of cellular proteins become transiently phosphorylated on tyrosine residues. One of these proteins, as we and others have shown previously, is the EpR itself. To identify the remaining protein substrates, we have examined the antiphosphotyrosine immunoprecipitates of lysates from Ba/F3 cells expressing high levels of cell surface EpRs. We now present data showing that, in response to Ep, the 85-Kd regulatory subunit of phosphatidylinositol 3-kinase (PI 3-kinase) becomes immunoprecipitable with antiphosphotyrosine antibodies. This appears to be due, in large part, to the specific association of PI 3-kinase with the tyrosine- phosphorylated EpR, either directly or through a 93- or 70-Kd tyrosine- phosphorylated intermediate. The activity of this EpR associated PI 3- kinase, assessed in anti-EpR immunoprecipitates, is maximal within 2 minutes of incubation with Ep and returns almost to baseline levels by 10 minutes. In vitro studies suggest that the interaction between PI 3- kinase and the activated EpR is mediated by the N- and C-terminal SH2 domains of p85 and tyrosine-phosphorylated motifs on the EpR.  相似文献   
794.
Aim: It is known that botulinum neurotoxin type A (BoNTA) improves some kinds of cancer (e.g. prostate) and that synaptic vesicle glycoprotein 2 (SV2) is the molecular target of this neurotoxin. Besides having potential therapeutic value, this glycoprotein has recently been proposed as a molecular marker for several types of cancer. Although the mechanisms of cancer development and the improvement found with botulinum treatment are not well understood, the formation of the botulinum-SV2 complex may influence the presence and distribution of SV2 and the function of vesicles. To date, there are no reports on the possible effect of botulinum on breast cancer of unknown causes, which have a great impact on women’s health. Thus we determined the presence of SV2 in three breast cancer cell lines and the alterations found with botulinum application. Materials and methods: With and without adding 10 units of botulinum, SV2 protein expression was determined by optical densitometry in T47D, MDA-MB-231 and MDA-MB-453 cell lines and the distribution of SV2 was observed with immunochemistry (hematoxylin staining). Results: The SV2 protein was abundant in the cancer cells herein tested, and maximally so in T47D. In all three cancer cell lines botulinum diminished SV2 expression, which was found mostly in the cell periphery. Conclusion: SV2 could be a molecular marker in breast cancer. Its expression and distribution is regulated by botulinum, suggesting an interesting control mechanism for SV2 expression and a possible alternative therapy. Further studies are needed in this sense.  相似文献   
795.
[概述]创面生理性愈合仍是当今国际医学界的一个棘手问题.目前, 创面处理的方法随着细胞生物学与生物活性因子学的发展发生了根本性变化, 对创面愈合机理也有了更深入的研究.创面形成的原因包括外源性损伤因素, 如急、慢性机械性损伤, 物理性或化学性烧伤, 冻疮, 感染或毒素, 内源性损伤因素如基因变异、血管病变、自身免疫性疾病、代谢紊乱、癌变或身心疾病等.  相似文献   
796.
Background and aimsBMV is an established treatment for rheumatic mitral valve stenosis. The procedure is historically guided by fluoroscopy, and the role of intracardiac echocardiogram (ICE) guidance is not well defined. We report our initial experience of using ICE to guide BMV procedures.MethodsDuring BMV procedure, ICE catheter was inserted into the right atrium from the right femoral vein, and the septal puncture was monitored by ICE, as well as positioning of the balloon in the mitral valve. Comparisons were made between ICE, transthoracic echocardiography (TTE), and catheterization derived hemodynamic measurements (cath).ResultsSeventeen patients with mitral stenosis underwent the procedure. The mean age was 44.4 ± 21 years. The mean MV area increased from 0.9 ± 0.1 cm2 to 1.7 ± 0.2 cm2, P < 0.0001 and the mean gradient decreased from 12.6 ± 5.8 mmHg to 4.9 ± 1.8 mmHg, P < 0.001. Atrial septum puncture and guidance of the balloon into the MV apparatus were obtained in all patients under ICE guidance. Severe MR developed in one patient and was readily detected by ICE. ICE derived gradient measurements were comparable to those obtained by TTE, and cath.ConclusionICE guidance of BMV is feasible, and useful in monitoring safe septal puncture, optimizing balloon positioning, and in detecting complications. The hemodynamic measurements obtained were comparable to those obtained by TTE, and cath.  相似文献   
797.
BACKGROUND: Little is known about the prevalence of and risk factors for human T-lymphotropic virus type I and type II (HTLV-I, HTLV-II) infections in Brazil. STUDY DESIGN AND METHODS: Sera from 17,063 healthy Brazilian donors were screened by enzyme-linked immunosorbent assay for antibody to HTLV-I/II between August 1991 and July 1993. Repeatedly reactive samples were confirmed by Western blot, and discrimination between HTLV-I and HTLV-II was made by polymerase chain reaction or synthetic peptide enzyme-linked immunosorbent assay. A univariate analysis was performed on demographic and serologic data. RESULTS: HTLV-I infection was demonstrated in 83 percent of the 30 donors with reactive serologic tests (0.15% of the total tested [17,063]; 95% CI, 0.09-0.20) and HTLV-II infection in 17 percent (0.03% of the total tested [17,063]; 95% CI, 0.01-0.05). HTLV-I-positive donors were more likely than reference groups to be of Asian ethnicity (odds ratio [OR] 15.1; reference group: whites), more than 50 years old (OR 4.2; reference group: 20–29 years old), and positive for antibody to hepatitis C virus (anti-HCV) (OR 21.8) or to hepatitis B core (antigen) (anti-HBc) (OR 5.7). HTLV-II showed a significant association with anti-HCV (OR 75.2) and anti-HBc (OR 21.8). Eleven of the 25 HTLV-I- positive donors were counseled. Family origin in endemic areas of Japan (n = 4), prior blood transfusion (n = 3), or sexual contact with prostitutes (n = 1) were the risk factors reported by 8 donors. In 3 white men, no risk factors could be identified. CONCLUSION: Both HTLV-I and HTLV-II occur among Brazilian blood donors. HTLV-I is associated with Asian ethnicity, greater age, and the presence of anti-HCV and anti-HBc. Three HTLV-I-positive donors had a history of blood transfusion, which emphasizes the need for HTLV-I/II screening in Brazil.  相似文献   
798.
The relationship between the various haemodynamic abnormalities observed in cirrhosis and their prognostic value remains unclear. We report haemodynamic measurements on 96 patients with alcoholic cirrhosis (mean Childs-Pugh Score, CPS, 9.0 +/- 0.2, mean age 55.6 +/- 1.0 years) and assess their value in predicting variceal bleeding and death during a mean follow-up of 19.3 +/- 1.5 months. Baseline CPS correlated with hepatic venous pressure gradient (HVPG) (p = 0.001), azygos blood flow (p < 0.05), cardiac index (p < 0.05), and inversely with mean arterial pressure (p < 0.01) and systemic vascular resistance index (p < 0.05). Renal blood flow was not related to any haemodynamic parameter or CPS. Thirty-eight patients died during follow-up, and 16 had a variceal bleed. Death (p = 0.001) and variceal bleeding (p < 0.05) were more likely in patients with HVPG > 16 mmHg than in those with HVPG < 16 mmHg, and variceal bleeding was more likely in patients with HVPG > 12 mmHg (vs. HVPG < 12 mmHg, p < 0.05). HVPG also predicted death and variceal haemorrhage on univariate and multivariate analyses. No other haemodynamic parameter predicted death or bleeding. In alcoholic cirrhosis, severity of liver disease is related to HVPG, collateral blood flow and degree of systemic circulatory abnormalities. HVPG is a useful predictor of survival and variceal bleeding in these patients.   相似文献   
799.
BACKGROUND: Trypanosoma cruzi, the cause of Chagas' disease, is often transmitted by transfusion in Latin America. Previous studies showed that at least 1 in 1000 eligible blood donors at the Los Angeles County+University of Southern California (LAC+USC) Medical Center Blood Bank had specific antibodies to T. cruzi. In June 1993, serologic screening of prospective allogeneic donors at epidemiologic risk for T. cruzi infection was begun voluntarily. STUDY DESIGN AND METHODS: The risk of T. cruzi infection in all eligible donors was assessed by questionnaire. At-risk donors were screened serologically for antibodies to T. cruzi with an enzyme immunoassay, and confirmatory testing was done with a radioimmunoprecipitation assay. RESULTS: During the 29-month study period 1311 (39.5%) of 3320 donors were judged to be at risk for T. cruzi infection. Seven donors (1/475) were reactive by an enzyme immunoassay, and six of these seven (1/ 553) were positive in a radioimmunoprecipitation assay. All radioimmunoprecipitation assay- positive donors had been born in countries in which Chagas' disease is endemic. One person in this group had received a transfusion in his homeland. CONCLUSION: These results demonstrate that a substantive proportion of eligible blood donors at our institution have antibodies specific for T. cruzi and that a commercially available assay can be used to detect these antibodies. Our data suggest that the risk of transmission of T. cruzi by transfusion could be eliminated by serologic testing limited to persons born in or transfused in countries in which Chagas' disease is endemic.  相似文献   
800.
HLA antigens in Omani patients with vitiligo   总被引:7,自引:0,他引:7  
Fifty native Omanis with vitiligo were studied to compare the incidence of HLA ABC and DR antigens with a control population. HLA Bw6 was found in 82% of patients compared with 49% controls (Pc= 0.0009 RR = 4.56) and HLA DR7 occurred in 40% of patients and 9% in controls (Pc= 0.00075 RR = 6.17). HLA DR7 was significantly increased in those patients with acrofacial, compared to focal disease (57% vs. 24%P= 0.038). Sixty-six per cent of the patients in this study had parents who were consanguineous and a positive family history was only found in this group with an incidence of 32%. HLA Bw4 segregated 100% with patients with a positive family history compared with 48% in consanguineous patients without a positive family history (Pc= 0.011 RR = 23). Vitiligo appears to be associated with different HLA antigens in different ethnic groups.  相似文献   
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