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41.
The aim of this study was to investigate the changes in the levels of liver enzymes and urea associated with an outbreak of cysticercosis (Taenia taeniformis) in rat liver. At the end of a previous trial, the animals were euthanized and necropsied when cysts of T. taeniformis were found. The number of cysts ranged from ten to 30 per rat liver. Blood samples were collected from ten rats with cysticercoids (from 12 to 22 cysts) and from ten non-affected rats that were kept in another animal house. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and urea values were reduced when compared with non-parasitized animals; alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) values were increased. Since the current experiment had to be repeated due to hepatic impairment evidenced by reduced ALT, AST, and urea values and increased ALP and GGT values, this study aims to alert the scientific community to the importance of sanitary barriers in animal housing.  相似文献   
42.
The recent emergence of stem cell-based tissue engineering has now opened up new venues for gene therapy. The task now is to develop safe and effective vectors that can deliver therapeutic genes into specific stem cell lines and maintain long-term regulated expression of these genes. Human artificial chromosomes (HACs) possess several characteristics that require gene therapy vectors, including a stable episomal maintenance, and the capacity for large gene inserts. HACs can also carry genomic loci with regulatory elements, thus allowing for the expression of transgenes in a genetic environment similar to the chromosome. Currently, HACs are constructed by a two prone approaches. Using a top-down strategy, HACs can be generated from fragmenting endogenous chromosomes. By a bottom-up strategy, HACs can be created de novo from cloned chromosomal components using chromosome engineering. This review describes the current advances in developing HACs, with the main focus on their applications and potential value in gene delivery, such as HAC-mediated gene expression in embryonic, adult stem cells, and transgenic animals.  相似文献   
43.
Using three waves of data from an ongoing study of current and former university employees (N = 1,656), the authors reexamined the roles of sexual (SH) and generalized (GWH) workplace harassment and gender in predicting use of professional services by focusing on patterning (chronic, remission, onset, intermittent, and never harassed). The authors also reexamined whether services moderated relationships between SH and GWH patterns and drinking and mental health outcomes. All patterns of SH, but only chronic GWH, predicted increased odds of services use. Services use did not moderate relationship between SH patterns and outcomes, but was associated with lower alcohol consumption for men with GWH remission or chronicity, reduced escape drinking for those with GWH remission, and reduced hostility for those with intermittent GWH.  相似文献   
44.
Meckel-Gruber syndrome (MKS) is a lethal fetal disorder characterized by diffuse renal cystic dysplasia, polydactyly, a brain malformation that is usually occipital encephalocele, and/or vermian agenesis, with intrahepatic biliary duct proliferation. Joubert syndrome (JBS) is a viable neurological disorder with a characteristic “molar tooth sign” (MTS) on axial images reflecting cerebellar vermian hypoplasia/dysplasia. Both conditions are classified as ciliopathies with an autosomal recessive mode of inheritance. Allelism of MKS and JBS has been reported for TMEM67/MKS3, CEP290/MKS4, and RPGRIP1L/MKS5. Recently, one homozygous splice mutation with a founder effect was reported in the CC2D2A gene in Finnish fetuses with MKS, defining the 6th locus for MKS. Shortly thereafter, CC2D2A mutations were also reported in JBS. The analysis of the CC2D2A gene in our series of MKS fetuses, identified 14 novel truncating mutations in 11 cases. These results confirm the involvement of CC2D2A in MKS and reveal a major contribution of CC2D2A to the disease. We also identified three missense CC2D2A mutations in two JBS cases. Therefore, and in accordance with the data reported regarding RPGRIP1L, our results indicate phenotype–genotype correlations, as missense and presumably hypomorphic mutations lead to JBS while all null alleles lead to MKS. Hum Mutat 30:1–9, 2009. © 2009 Wiley-Liss, Inc.  相似文献   
45.
Objective: To present a case of an early treatment of cardiac intraperitoneal teratoma (IPT) in a newborn and its associated systematic literature review.

Methods: We presented a case of a newborn with IPT but without hydrops and having a good perinatal outcome after cardiac surgery. Using the PubMed database, we conducted a systematic literature review of articles regarding cases with cardiac IPT diagnosed and treated in the neonatal period and published in English from 2004 onward. We excluded cases that involved fetal death or interrupted gestation events.

Results: In total, 38 cases of IPT from 31 articles were included. The mean?±?standard deviation of the gestational age at diagnosis and delivery were 27.9?±?5.7 and 33.0?±?3.5 weeks, respectively, and that of birth weight was 2373?±?834.5?g. The majority of fetuses (42.1%) were males. Pericardial effusion was the most common symptom (60.5%) followed by hydrops (42.1%) and respiratory distress (42.1%). Intrauterine procedure was not performed in 63.1% of cases, and 71.0% of newborns were alive.

Conclusions: IPT in newborns is usually associated with a good prognosis without the need for intrauterine procedures. Cases with IPT-related death are associated with hemodynamic impairment in fetuses with hydrops.  相似文献   
46.
Escherichia coli O15:K52:H1 is a significant extraintestinal pathogen in Europe (G. Prats et al., J. Clin. Microbiol. 38:201-209, 2000). To search for evidence of this clonal group outside of Europe, 75 non-European E. coli isolates of serogroup O15 were compared with five members of the O15:K52:H1 clonal group from Barcelona, Spain, according to genomic background, virulence genotypes, and antimicrobial resistance profiles. Amplification phylotyping showed that 16 (21%) of the 75 non-European O15 isolates corresponded with the O15:K52:H1 clonal group. The 16 non-European O15:K52:H1 clonal group members represented diverse geographic locales. They were isolated almost exclusively from humans with extraintestinal infections and accounted for 50% of all O15 isolates from five human clinical collections studied. Most non-European clonal group members exhibited a consensus virulence factor profile that included the F16 or F7-2 papA alleles (P fimbrial structural subunit), papG allele II (P fimbrial adhesin), iha (putative adhesin siderophore), and iutA (aerobactin receptor). This resembles the virulence profiles of (i) European representatives of the O15:K52:H1 clonal group and (ii) phylogenetically related "clonal group A," a recently recognized significant contributor to trimethoprim-sulfamethoxazole resistance in the United States (A. R. Manges et al., N. Engl. J. Med. 345:1007-1013, 2001). Antimicrobial resistance profiles were variable, and resistance was inconsistently transferred by conjugation. These findings indicate that the O15:K52:H1 clonal group is broadly distributed beyond Europe, exhibits previously unrecognized phenotypic and genotypic diversity, and contributes significantly to extraintestinal infections in humans.  相似文献   
47.
48.
It has been demonstrated by several laboratories that ethanol, both acute and chronic, produces effects that are age dependent. Specifically, adolescent rats are less sensitive to the hypnotic and motor-impairing effects of ethanol but are more sensitive to the hypothermic effects of the drug. However, the results on hippocampal function are not as clear. For example, there have been mixed findings regarding adolescent sensitivity of hippocampal-dependent (spatial) memory in response to ethanol. The current review explores the present state of the field as it relates to ethanol's effects in the hippocampus, particularly as it relates to spatial memory. In addition, we review potential neurobiological mechanisms that might underlie the age-dependent effects of ethanol in the hippocampus. Finally, future directions are proposed that will advance the state of the field as it relates to ethanol's effect during this developmental period.  相似文献   
49.
This study tested cervical and oral human papillomavirus (HPV) infection in HIV-1 seropositive (HIV+) and seronegative (HIV-) women to determine any association between infections at both sites and the difference in prevalence of the HPV types infecting these women. Participants were 115 women referred to a colposcopy clinic after diagnosis of abnormal cervical cytology. The women showed low grade cervical intraepithelial neoplasia (CIN1) or high grade disease (CIN2/3) or no CIN based on colposcopy and histology. Typing of HPV in cervical and oral cells was by Roche linear array and included direct sequencing on selected oral samples. Cervical HPV prevalence was 86.5% and 97.1% in HIV- and HIV+ women respectively. With the exception of HPV-45, prominent in HIV+ women, the hierarchy of predominant types were similar in HIV- and HIV+ women. HPV-16 was most prevalent in both HIV+ (41.7%) and HIV- women (38.5%) with CIN2/3. Significantly more HIV+ women had multiple cervical (>1) infections than HIV- women (36.1% vs. 88.2%, P < 0.001) and more oral HPV infections (45.5% and 25% respectively; P = 0.04). The most prevalent oral HPV types were HPV-33, -11, and -72. The majority of women did not have concordant oral and cervical HPV types, reflecting possible independence of infection at the two sites. HIV immune suppression did not impact significantly on the predominant types of cervical HPV infection (except for HPV-45). HIV+ women had more multiple HPV infections and those with severe cervical disease a similar prevalence of HIV-16 but a lower HPV-18 prevalence than HIV- women.  相似文献   
50.

Study objective

Inter-clinician communication accounts for more than half of all information exchanges within the health care system. A non-participatory, qualitative time-and-motion observational study was conducted in order to gain a better understanding of inter-clinician communication behaviors, routine workflow patterns, and the use of information communication technologies (ICTs) within the clinical workspace.

Method

Over a 5-day period, seven attending physicians and two nurses were shadowed for 2-4 h at a time. Inter-clinician communication events were tracked in real-time using synchronized digital stopwatches. Observations were recorded on a paper-based, semi-structured observation tool and later coded for analysis.

Results

Nine hundred and eighty-seven communication events were observed over 2024.67 min. Clinicians were observed to spend the majority of their time on patient care (85.4% in this study) with about three-fourths of that time spent on indirect patient care (e.g. charting). Clinicians were observed to prefer using synchronous communication modes, which led to multitasking and created a highly interrupted workflow. Forty-two percent (n = 415) of communication events were coded as interruptions and study participants were seen multitasking 14.8% of the time. Though each interruption was short-lived (on average 0.98 ± 2.24 min for attending physicians), they occurred frequently. Both attending physicians and nurses were the recipients of more interruptions than they initiated.

Conclusion

This study demonstrated that the clinical workspace is a highly interruptive environment. Multiple interruptions in the communication processes between clinicians consume time and have the potential to increase the risk of error. This workflow analysis may inform the development of communication devices to enhance inter-clinician communication by reducing interruptions or deferring interruptions to more appropriate times.  相似文献   
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