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1.
Postoperative nausea and vomiting (PONV) and postdischarge nausea and vomiting (PDNV) are common occurrences (50%-80%) after laparoscopic surgery. Palonosetron (Pal), the newest 5-HT3 antagonist, is an effective antiemetic that has advantages in treating PDNV due to its prolonged duration of action. We hypothesized that a combination of Pal and dexamethazone (Dex) could further improve the efficacy of the treatment in comparison to Pal alone in patients at high risk for PONV. Patients scheduled to undergo laparoscopic surgeries under general anesthesia were randomized to receive 8-mg dexamethasone + 0.075-mg palonosetron (Pal + Dex) or an equivalent volume of saline + 0.075 mg palonosetron (Pal). Data was collected at defined postoperative times (2, 6, 12, 24, and 72 hours). All patients also completed an 18-question QOL-Functional Living Index-Emesis instrument at 96 hours. We enrolled 118 patients, ASA 1-2, with at least 3 PONV risk factors, who were undergoing outpatient surgery. Both groups had a low incidence of vomiting in the PACU (Pal + Dex, 1.7%; Pal, 6.8%) and at 72 hours (0.0% both groups). Complete response (no vomiting, no rescue medication) was not different between treatment groups for any time intervals. Cumulative success rates over the entire 72 hours were 60.4% (Pal + Dex) versus 60.0% (Pal). The Pal + Dex group showed a trend toward greater satisfaction on the QOL- Functional Living Index-Emesis scores with the greatest differences in the "nausea domain". The combination therapy of palonosetron + dexamethasone did not reduce the incidence of PONV or PDNV when compared with palonosetron alone. There was no change in comparative efficacy over 72 hours, most likely due to the low incidence of PDNV in both groups.  相似文献   
2.
The mechanism of induction of apoptosis by double-stranded RNA (dsRNA) is not fully characterized. The dsRNA is normally present in extremely low quantities in cells, but following infection with RNA viruses, large quantities of the dsRNA viral replicative intermediate may be produced triggering the antiviral response as well as cell death. In this report, transfection of polyinosinic-polycytidylic acid [poly(I:C)] into NIT 1 cells has been used as a model of intracellular dsRNA-induced beta-cell apoptosis. At 18 h post transfection, 45% of the cells were apoptotic as indicated by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL) staining, and this was accompanied by an increase in nuclear factor kappaB (NF-kappaB) p50/p65 nuclear translocation and cleavage of caspases 3 and 8. The NF-kappaB inhibitor peptide, SN50, significantly reduced caspase-3 activity and the percentage of TUNEL-positive cells, substantiating a role for NF-kappaB in inducing intracellular dsRNA-mediated apoptosis. Concomitantly, RNA-dependent protein kinase activity was observed at 3 h post transfection along with phosphorylation and degradation of inhibitory kappaB-alpha. Expression of TRAIL (TNF-related apoptosis-inducing ligand), Fas, IL-15, and caspase-12 mRNAs was up-regulated in the presence of poly(I:C) but not when SN50 was also added. In contrast, there was no change detected in Fas, Fas-associated death domain, Bcl-2, Bcl-xl, Bax, p53, or XIAP(X-linked inhibitor of apoptosis protein) expression up to 12 h after poly(I:C) transfection. In addition, caspase-12 was cleaved, and phosphorylation of eukaryotic initiation factor 2alpha occurred, suggesting that an endoplasmic reticulum stress pathway was involved in addition to NF-kappaB induction of an extrinsic pathway, possibly mediated by TNF-related apoptosis-inducing ligand.  相似文献   
3.
Treponema denticola is an important contributor to periodontal disease. In this study we investigated the ability of T. denticola to bind the complement regulatory proteins factor H and factor H-like protein 1 (FHL-1). The binding of these proteins has been demonstrated to facilitate evasion of the alternative complement cascade and/or to play a role in adherence and invasion. Here we demonstrate that T. denticola specifically binds FHL-1 via a 14-kDa, surface-exposed protein that we designated FhbB. Consistent with its FHL-1 binding specificity, FhbB binds only to factor H recombinant fragments spanning short consensus repeats (SCRs) 1 to 7 (H7 construct) and not to SCR constructs spanning SCRs 8 to 15 and 16 to 20. Binding of H7 to FhbB was inhibited by heparin. The specific involvement of SCR 7 in the interaction was demonstrated using an H7 mutant (H7AB) in which specific charged residues in SCR 7 were replaced by alanine. This construct lost FhbB binding ability. Analyses of the ability of FHL-1 bound to the surface of T. denticola to serve as a cofactor for factor I-mediated cleavage of C3b revealed that C3b is cleaved in an FHL-1/factor I-independent manner, perhaps by an unidentified protease. Based on the data presented here, we hypothesize that the primary function of FHL-1 binding by T. denticola might be to facilitate adherence to FHL-1 present on anchorage-dependent cells and in the extracellular matrix.  相似文献   
4.
5.
Pacific Islander women represent a significant at-risk population for cervical cancer, yet little is known about the modifiable factors associated with routine Pap testing. Therefore, the aims of this paper are to report and discuss the known and unknown factors associated with cervical cancer screening among Chamorro women in California. This cross-sectional study explored the factors associated with receipt of regular Pap testing among Chamorro women age 18 years and older in California. A self-administered survey was designed and distributed to women in order to understand their knowledge, beliefs and behaviors regarding routine receipt of Pap tests. Only about two-thirds of women had received a Pap test within the past 2 years, which is below the U.S. average of 72 %. Significant predictors included younger age, health insurance coverage, knowledge of screening frequency, and medically correct beliefs regarding risk groups. These factors, however, accounted for less than 16 % of the variance in Pap testing behavior. We discuss the poor predictive value of existing demographic and theoretical variables, and discuss potentially new areas of research that can aid in the development of future intervention studies. Study limitations and implications are also discussed.  相似文献   
6.
Long-term primary cultures were established fromfetal or neonatal livers by using cell suspensionsdepleted of red blood cells and by culturing the cellsin hormonally defined medium containing dimethyl sulfoxide. Two distinct populations of hepaticprogenitor cells were evident in the cultures, based onmorphology, proliferative ability, and liver-specificgene expression. Most colonies consisted of immature hepatic progenitors: small, blastlike cells,weakly expressing alpha-fetoprotein, albumin, and-glutamyltranspeptidase, and showing evidence ofproliferation as measured by bromodeoxyuridineincorporation. At the perimeter of these colonies of immaturecells and forming some colonies by themselves were moremature hepatic progenitor cells: larger cells, withincreased cytoplasmic to nuclear ratios, little proliferation, and strongly expressing albumin,alpha-fetoprotein, and -glutamyltranspeptidase.The latter two proteins were localized to the bilecanalicular membranes of these cells. Glycogen deposits were present in the mature cells from day 14embryos after eight days of culture. Thus, DMSOtreatment of hepatic parenchymal progenitors provides anovel system for studies of liver development.  相似文献   
7.
The coronavirus disease 2019 pandemic presents unprecedented challenges for the health care system. The pressure on health care staff continues to intensify, accentuated by the confinement (lockdown) of the population and the unprecedented duration of this emergency. Separately and especially together, overwork, degraded conditions of care because of the never-ending emergency, and the risk of exposure to the virus can lead to acute psychological distress or signs of burnout.This original program was developed at Cochin Hospital in Paris, France to prevent these potentially dramatic psychological consequences, support the medical staff, and identify those most affected to offer them specific care. A program and a space for relaxation and support for hospital caregivers by hospital caregivers, the Port Royal Bulle (the Bubble) offers these workers help in decompression and relaxation. It combines a warm and caring welcome that promotes attention, listening, conversations, and exchanges as needed, empathetic support, and the ability to participate in soothing, relaxing, or low-impact physical activities. It takes care of caregivers. The Bubble is a program that is simple to set up and that appears to meet professionals' expectations. Making it permanent and enlarging its scale, as a complement to existing programs, might help to support health care personnel in their work.  相似文献   
8.
Pinta is a neglected, chronic skin disease that was first described in the sixteenth century in Mexico. The World Health Organization lists 15 countries in Latin America where pinta was previously endemic. However, the current prevalence of pinta is unknown due to the lack of surveillance data. The etiological agent of pinta, Treponema carateum, cannot be distinguished morphologically or serologically from the not-yet-cultivable Treponema pallidum subspecies that cause venereal syphilis, yaws, and bejel. Although genomic sequencing has enabled the development of molecular techniques to differentiate the T. pallidum subspecies, comparable information is not available for T. carateum. Because of the influx of migrants and refugees from Latin America, U.S. physicians should consider pinta in the differential diagnosis of skin diseases in children and adolescents who come from areas where pinta was previously endemic and have a positive reaction in serological tests for syphilis. All stages of pinta are treatable with a single intramuscular injection of penicillin.The endemic treponematoses, pinta, yaws, and bejel, are caused by spiral-shaped, not-yet-cultivable bacteria of the genus Treponema.13 These neglected infectious diseases (NIDs), for which there are no vaccines, present a diagnostic dilemma to physicians because their clinical manifestations must be differentiated from those of other diseases that affect the skin. Moreover, serological tests cannot differentiate the endemic treponematoses from each other or from venereal syphilis, which is caused by the closely related spirochete, Treponema pallidum subspecies pallidum. Unlike venereal syphilis, the endemic treponematoses are usually acquired by children or adolescents living in poor rural communities in tropical climates (see references 1 and 2 for maps showing the geographical distribution of endemic treponematoses). Whereas venereal syphilis has a global distribution and is transmitted primarily by sexual activity, the endemic treponematoses are transmitted by nonsexual, direct skin-to-skin contact with infectious lesions.Pinta, also known as mal del pinto or carate, is the most benign of the endemic treponematoses since it affects only the skin.13 Pinta was first described in the sixteenth century in the Aztec and Carib Amerindians by Spanish conquistadors and missionaries.4 In the 1950s, there were an estimated 1 million cases of pinta in Mexico, Central America, and northern South America. Although pinta was most highly endemic in Mexico and Columbia, cases declined in these countries due to treatment campaigns and possibly due to improvements in living standards, access to health services, and hygiene.4,5 The World Health Organization (WHO) lists 15 countries in Latin America where pinta was previously endemic. Because of the lack of surveillance data, the current prevalence of pinta is unknown. However, some findings suggest that pinta has not disappeared. For example, in 1982 and 1983, clinical evidence of pinta was discovered in 20% of the examined inhabitants of a remote village in Panama.6 In 1987 and 1993, pinta cases were reported in native Indians (Ticuna) living in the Amazon border region of Brazil, Columbia, and Peru.7,8 Although the last reported case of pinta in Cuba was in 1975, an active, early pinta lesion was identified in a Cuban female who was visiting Austria in 1999.9 On the basis of these data, it is plausible that pinta has remained endemic in some remote areas of Latin America where access to health services is limited and living standards have not yet risen.1,2Like syphilis, pinta is classified into stages (see references 13 for pictures of the clinical stages of pinta). The primary stage is characterized by the presence of one or several papules or erythematous scaly plaques that develop about 3 weeks after infection. The body area most commonly affected is the exposed skin of the extremities. The papule or plaque, which is teeming with infectious treponemes, does not ulcerate, but expands to a diameter of 10 cm or greater. Regional lymphadenopathy is common. During early infection, serological tests for syphilis (STS) may be negative for antibodies to nontreponemal (cardiolipin) and treponemal antigens. Plaques may last for months to years and pigmentary changes may be observed in the plaques. The lesions may heal spontaneously or they may persist and become indistinguishable from the lesions of secondary pinta.The secondary stage usually appears several months after the initial manifestations of the primary stage.13 Small disseminated lesions known as “pintids” may coalesce into plaques. The pintids change from an initial red color to brown, slate-blue, black, or gray colors. Different pigmentation may occur within a pintid. The secondary lesions can remain active and infectious for a long time, leading to extensive depigmentation. STS are positive in the majority of untreated cases.The late (tertiary) stage usually develops 2–5 years after initial infection and is characterized by pigmentary abnormalities (i.e., from dyschromic treponeme-containing lesions to achromic treponeme-free lesions), skin atrophy, and hyperkeratosis.13 The degree of lesion pigmentation can be different in the same patient, resulting in a mottled appearance of the skin, which can persist lifelong. Lesions may turn into various colors (e.g., brown, gray-blue, or black). STS are positive in virtually all untreated cases.The etiological agent of pinta, Treponema carateum, was not identified until over 30 years after the 1905 discovery of the related agents of venereal syphilis and yaws.4,1012 Initially, it was thought that a pathogenic fungus caused pinta. However, two observations suggested otherwise. First, laboratory studies of pinta patients'' sera showed that the Wassermann test, an early STS, was positive in the majority of cases. Second, treatments that were effective against syphilis (i.e., mercury and arsenicals) were also effective against pinta. In August 1938, Sáenz and others10 using dark-field microscopy, demonstrated the presence of spirochetes that were morphologically indistinguishable from the T. pallidum subspecies in exudate from a Cuban pinta patient''s lesions. Subsequently, other investigators reported the presence of spirochetes in pinta lesions. Because the presence of these bacteria was insufficient to prove causality, León-Blanco performed skin inoculation experiments on himself and human volunteers with lesion exudate that contained the spirochetes and succeeded in reproducing the early manifestations of pinta.4,12 León-Blanco also showed that some immunity to reinfection develops during pinta. Patients with late-stage pinta could not be reinfected, whereas patients whose early-stage pinta had been cured could be reinfected. Furthermore, León-Blanco and Briceno Ross and Iriarte demonstrated that syphilis and yaws patients, respectively, were not immune to infection with pinta, despite the antigenic similarity of the etiological agents.4,11,12Because animal models are necessary to propagate the T. pallidum subspecies for experimental studies, several investigators attempted to determine if laboratory animals could be infected with T. carateum.11 León-Blanco and Oteiza13 reported infection of one of the four rabbits that they inoculated intradermally with exudate from a pinta patient''s lesions. However, they were unable to successfully passage T. carateum from the rabbit''s lesion to other rabbits. Later, Kuhn and others14 demonstrated that chimpanzees could be infected intradermally and that these animals developed lesions similar to those of pinta patients. Unfortunately, T. carateum isolates are not available for study. Although phylogenetic data obtained via genomic sequencing have enabled the development of techniques to differentiate the T. pallidum subspecies, comparable information is not available for T. carateum.1,2 Thus, despite the morphological and antigenic relatedness of the agents of pinta and syphilis, molecular knowledge of T. carateum is currently insufficient to warrant classification of this spirochete as a T. pallidum subspecies.Pinta can be treated with a single intramuscular injection of long-acting benzathine penicillin (1.2 MU for adults; 0.6 MU for children), which renders the lesions noninfectious in less than 24 hours.1,3,11 Information is scant concerning the efficacy of other antibiotics. Although early pinta lesions heal within several months after penicillin administration, this treatment cannot reverse the skin changes of late pinta that can stigmatize those who were infected.4 Penicillin treatment was the mainstay for the “National Campaign to Eradicate Mal del Pinto” conducted in Mexico (1960s) and for the WHO campaign against the endemic treponematoses (1952–1964).1,2,4 A national campaign against yaws that was conducted in Columbia in the 1950s resulted in an almost parallel decline in the incidence of both yaws and pinta, even though pinta was not specifically targeted.5 Despite the initial success of these campaigns, the endemic treponematoses, particularly yaws, have resurged due to the lack of sustained resources and political will. The WHO has initiated a campaign to eradicate yaws by 2020 that is based on mass treatment of endemic communities with an oral dose of azithromycin, a macrolide antibiotic with demonstrated efficacy against yaws.1,2,15 If T. carateum is sensitive to azithromycin as is likely, this treatment strategy could have a concomitant effect on pinta in areas of Latin America where yaws and pinta may be co-endemic. Moreover, if the endemic treponematoses were rolled into the program area of the Pan American Health Organization''s (PAHO''s) Strategic Plan (2014–2019) that targets selected NIDs and focuses on strengthening national capacity for screening, treatment, and surveillance of NIDs, this could facilitate elimination of pinta and yaws in PAHO member countries and would aid WHO''s yaws eradication campaign (www.paho.org/hq/).The possibility of importation of NIDs such as the endemic treponematoses increases as record numbers of migrants and refugees from Latin America continue to enter the United States for economic or political reasons.2,3,16 Accordingly, physicians should consider pinta in the differential diagnosis of skin diseases for Latin American children and adolescents who come from areas where pinta was previously endemic and have a positive reaction in STS.3,16 This is critical to guide treatment as well as to avoid the inadvertent psychological harm and legal ramifications that can result from making an incorrect diagnosis of syphilis. Although pinta may be a forgotten disease, it is unlikely to be extinct.9,17  相似文献   
9.
The pattern of DNA polymerase activity in developing Drosophila melanogaster has been studied in seven stages of embryonic development as well as in unfertilized eggs. The crude polymerase-containing extracts, most likely of cytoplasmic origin, utilize, in the following order of decreasing template efficiency, "activated" calfthymus DNA, poly(A).oligo(dT), and poly(A).oligo(U). The highest enzymes levels occur in unfertilized eggs; the activity remains high during the first 9 hr of embryogenesis, but shows a progressive decline in the later stages. Deoxyribonuclease exhibits a similar trend. The unfertilized eggs of two genotypically different females had nearly identical levels of DNA polymerase.  相似文献   
10.
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