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1.
The reduction in morbidity and mortality since the enforcement of seat-belt usage is well documented. Complications from the belt are also reported and the authors present anterior dislocation of the restrained shoulder, an injury not previously described. The mechanism of injury is explained and a change to the present standard of restraints is suggested.  相似文献   
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OBJECTIVE: To report on the high incidence of anatomical variants of the origin and course of the internal spermatic vein (ISV) discovered at the time of percutaneous embolization of left varicoceles in a pediatric population. METHODS: We reviewed retrospectively the 65 cases of left varicocele treated by percutaneous embolization (grade II and III) in our institution between 1990 and 2000. The course of the left renal vein (LRV), the origin of the ISV, and the number of ISVs and their pathway were recorded in all cases, according to the B?hren classification. RESULTS: In 37/65 (57%), the ISV was single and arose from a normal LRV (type I). The following variants were encountered: type V--circumaortic LRV 9/65 (14%); type IVb--intrarenal origin of ISV 8/65 (12%); type II--multiple ISV 5/65 (8%); and pelvic collaterals 6/65 (9%). CONCLUSION: Venous anatomical variants are frequently encountered (43%) at the time of left varicocele embolization in children. Such variants often impose some adjustments to the technique of embolization and, at times, hamper the procedure.  相似文献   
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Cytokines in the stools of children with complicated shigellosis.   总被引:1,自引:1,他引:1       下载免费PDF全文
The pathogenesis of the systemic complications, leukemoid reaction and hemolytic uremic syndrome, associated with Shigella dysenteriae type 1 infection is not well understood. The excessive production of proinflammatory cytokines, including tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), has been suggested as a possible factor. We measured IL-6 and TNF-alpha in stools of 56 children with S. dysenteriae 1 infection and 29 children without any apparent infection, all age 12 to 60 months. Sixteen children with S. dysenteriae 1 infection had leukemoid reaction or hemolytic uremic syndrome (complicated shigellosis), while the others did not (uncomplicated shigellosis). Stool IL-6 and TNF-alpha concentrations were higher in children with uncomplicated shigellosis than in children with complicated shigellosis (P = 0.009 and < 0.001, respectively) or in uninfected children (P < 0.001). It is concluded that complicated infection is not associated with higher concentrations of the proinflammatory cytokines IL-6 and TNF-alpha in stool.  相似文献   
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An oral biofilm is a community of surface-attached microorganisms that coats the oral cavity, including the teeth, and provides a protective reservoir for oral microbial pathogens, which are the primary cause of persistent and chronic infectious diseases in patients with dry mouth or Sjögren''s syndrome (SS). The purpose of this study was to establish an animal model for studying the initial adhesion of oral streptococci that cause biofilm formation in patients with dry mouth and SS in an attempt to decrease the influence of cariogenic organisms and their substrates. In nonobese diabetogenic (NOD) mice that spontaneously develop insulin-dependent diabetes mellitus (IDDM) and SS, we replaced major histocompatibility complex (MHC) class II (Ag7 Eg7) and class I Db with MHC class II (Ad Ed) and class I Dd from nondiabetic B10.D2 mice to produce an animal model that inhibited IDDM without affecting SS. The adhesion of oral streptococci, including Streptococcus mutans, onto tooth surfaces was then investigated and quantified in homologous recombinant N5 (NOD.B10.D2) and N9 (NOD.B10.D2) mice. We found that a higher number of oral streptococci adhered to the tooth surfaces of N5 (NOD.B10.D2) and N9 (NOD.B10.D2) mice than to those of the control C57BL/6 and B10.D2 mice. On the basis of our observation, we concluded that these mouse models might be useful as animal models of dry mouth and SS for in vivo biological studies of oral biofilm formation on the tooth surfaces.Oral streptococci are present in large numbers in dental plaque, and several types interact with the enamel salivary pellicle to form a biofilm on tooth surfaces (9, 16, 17, 21, 29). Streptococci account for approximately 20% of the total number of salivary bacteria (24), with Streptococcus salivarius being the primary organism. Further, the densities of Streptococcus mutans and Streptococcus sanguis in saliva are more than 1 × 105 cells per ml. S. mutans is a pioneering organism that plays an important role in biofilm formation on tooth surfaces and is a primary causative agent of dental caries (9, 16, 21). The mechanical forces of salivary flow and tongue movement tend to dislodge and expel bacteria from tooth surfaces and the oral cavity (3, 5, 6), and their importance in controlling microbial colonization in the oral cavity has been well demonstrated in individuals with diabetes mellitus, Sjögren''s syndrome (SS), and dry mouth, who suffer from a rapid overgrowth of biofilm and rampant caries, making them highly susceptible to oral infections (1-2, 6). Thus, attempts to investigate the initial adhesion by oral streptococci, including S. mutans, in mouse models are likely to aid in the understanding and prevention of oral infectious diseases caused by the components of oral biofilm.Previous studies of S. mutans infections in the oral cavities of mice have been performed by feeding the animals diets containing sucrose in the presence of glucans (13, 15, 30, 43). Since the adherence of S. mutans to the tooth surface may depend on the balance between physical adherence and synthesis of insoluble glucans in a natural environment, that infection method may be inappropriate for investigation of natural biofilm formation associated with streptococci, including S. mutans (18, 39).The nonobese diabetogenic (NOD) mouse strain is currently the best available model for the study of insulin-dependent type 1 diabetes mellitus (IDDM) and SS (11, 31), both of which develop spontaneously and are characterized by lymphatic infiltration of the pancreas and salivary glands. Oral changes are prominent features of these diseases, which are manifested by dry mouth and hyposalivation (6, 7, 37). NOD mice are also used as an animal model for the study of oral infectious diseases associated with systemic diseases such as diabetes and SS or dry mouth.The unique major histocompatibility complex (MHC) class II genes (I-Ag7, no expression of I-E) represent dominant susceptibility factors and mediate activated T cells during the development of diabetes in NOD mice (11, 22, 25, 36, 41, 42). In the NOD model of SS, histopathological analyses of the salivary glands in MHC-congenic strains of NOD mice have indicated that the I-Ag7 region is not required for lymphocytic infiltration (26, 31). Further, replacement of the NOD MHC class I Kd region with another haplotype, MHC class I Kwm7, as well as replacement of the MHC class II Ag7 Eg7 and class I Dd regions with the corresponding region from the other MHC haplotype, has been shown to prevent diabetes (12). However, replacement with MHC class I K does not completely prevent development of insulitis. In another report, NOD mice pretreated nasally by using peptides restricted with MHC class I Kd showed a delayed onset of spontaneous IDDM, though insulitis could not be prevented by the induction of tolerance (23).In the present study, we attempted to establish an animal model for oral infectious diseases such as dental caries by focusing on replacement of the MHC class II and class I D region but not the class I K region in nondiabetic NOD mice by outcrossing B10.D2 mice (Kd, I-Ad, and Dd) with NOD mice (Kd, I-Ag7, and Db) because the MHC class I K region in B10.D2 mice is identical with that in NOD mice (12). The present backcrossed and intercrossed NOD mice with the MHC class II and MHC class I D region replaced with that from B10.D2 mice developed SS, however, not diabetes. We then attempted to determine whether these mice would be useful as animal models for a sucrose-free study of the initial adhesion of oral streptococci on tooth surfaces in humans.  相似文献   
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A minority of individuals infected with the parasite Schistosoma mansoni develops hepatic fibrosis. HLA studies in Egypt and a candidate gene search in a Sudanese population indicate that the host's genetics contribute to disease susceptibility. In an Egyptian community, 32.7% of individuals 11 years and older had significant fibrosis by WHO ultrasound criteria. Linkage to 10 candidate genes was tested using 89 affected sibling pairs from 40 pedigrees in this community. The candidates included genes that initiate fibrosis, participate in collagen synthesis, or control collagen degradation. Two to four single-nucleotide polymorphisms (SNPs) were genotyped per locus, and 188 individuals were genotyped at 48 markers. Model-free modified Haseman-Elston analysis identified linkage to a SNP in the interferon gamma receptor locus (P=0.000001). There was also weak evidence for linkage to the interleukin 13-4 region and tissue growth factor beta 1.  相似文献   
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Vibrio cholerae serogroup O139, now considered to be the second organism capable of causing epidemic severe dehydrating cholera, contains a capsular polysaccharide which makes it difficult for it to be used in the conventional vibriocidal antibody assay optimized for V. cholerae O1. After modification of the procedure, which involved the use of specific bacterial strains, a lower bacterial inoculum, and increased amounts of complement, the vibriocidal antibody responses to V. cholerae O139 were measured in acute- and convalescent-phase sera from 33 V. cholerae O139-infected and 18 V. cholerae O1-infected patients and in single serum samples from 20 healthy control subjects. The responses in these individuals to V. cholerae O1 strains were also determined. Significant elevations in the homologous antibody response were found only in the convalescent-phase sera from both groups of patients with cholera. These findings may explain the basis for the lack of heterologous protection between the two serogroups of V. cholerae. Healthy controls had higher background levels of vibriocidal antibody to V. cholerae O1 than to V. cholerae O139.  相似文献   
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Introduction/ObjectivesAcute kidney injury (AKI) and malnutrition are two complications commonly reported in severe forms of COVID-19, their combined effect on short-term mortality is, however, not yet investigated. The objective of this study is to determine both their individual and combined effects on short-term prognosis.Materials and methodsThis is a prospective, uni-centric study, including 247 severe COVID-19 patients, admitted between April 25th and June 20th, 2020, at the University Hospital of Blida. AKI was defined according to the KDIGO-2012 guidelines. Nutritional status was assessed using the Controlling Nutritional Status (CONUT) score. The association with in-hospital mortality was assessed using the Kaplan-Meier method and proportional Cox regression.ResultsAmong the 247 severely affected COVID-19 patients included in this study, 34.4% developed AKI, 30.4 and 1.2%, respectively, had moderate and severe CONUT scores, 17.7% worsened and progressed to a critical state and 26.7% did not survive. Both AKI and CONUT score were significantly associated with mortality in a dose-response manner (pLog-Rank < 0.0001). Their relative risks are respectively (HR = 3.25 CI 95% [1.99–5.3] and HR = 2.42 CI 95% [1.5–3.9], p < 0.0001). In multivariate analysis, the highest risk was observed for the AKI-CONUT-high combination (HR = 3.0, 95% CI [1.5–6.1], p = 0.002).ConclusionA possible synergistic interaction between AKI and CONUT score for COVID-19 short-term mortality has been highlighted. Monitoring of renal function associated with assessment of nutritional status should be performed routinely and systematically from the early stages of admission.  相似文献   
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