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11.
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We have previously reported the development of a recombinant vaccinia virus vaccine expressing the human carcinoembryonic antigen (CEA) gene, designated rV(NYC)-CEA. This construct has been shown to elicit specific anti-CEA immune responses and an antitumor effect in a murine tumor model. In the studies reported here, the safety and immunogenicity of this recombinant vaccinia virus were evaluated in a rhesus monkey model. Human CEA is a M(r) 180,000 glycoprotein expressed in approximately 90% of gastrointestinal carcinomas and in some breast and non-small cell lung carcinomas. This family also includes normal cross-reacting antigen (NCA). Rhesus monkeys, like humans, have some NCA on the surface of their granulocytes. Eight monkeys were immunized 3 or 4 times by skin scarification with the recombinant CEA vaccine and four monkeys received wild-type vaccinia virus as control. After three vaccinations, all rV(NYC)-CEA-vaccinated animals exhibited a strong anti-CEA antibody response as measured by enzyme-linked immunosorbent assay. The functional ability of these antibodies to mediate lysis of a CEA-bearing tumor cell was demonstrated using human effector cells. This response could be enhanced by interleukin 2. Cellular immunity to CEA was measured by delayed-type hypersensitivity upon intradermal challenge with purified CEA. Only those animals receiving the recombinant vaccine displayed significant anti-CEA responses. Furthermore, peripheral blood mononuclear cells from immunized monkeys were found to proliferate in response to CEA stimulation. All vaccinated monkeys developed local skin irritation at the site of the vaccination, regional lymphadenopathy, and low-grade fevers after immunization. Following immunization with rV(NYC)-CEA, the response was consistent with the usual constitutional symptoms seen with human smallpox virus immunization. Blood counts, differentials, and hepatic and renal chemistries remained normal in all animals throughout the study and for up to 1 year following the primary vaccination. No evidence of immunological cross-reactivity to NCA was found by either a fall in the granulocyte count or analyses for anti-NCA antibodies. Thus, the rV(NYC)-CEA vaccine appears to be safe in rhesus monkeys. The administration of a CEA recombinant vaccine to rhesus monkeys induces both a humoral and a cell-mediated immune response directed against human CEA.  相似文献   
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14.
Arguably, nursing, like all health care disciplines, is an applied science. Essentially, this refers to the application of theory in order to understand and respond to the health problems of clients. These theories may be drawn (borrowed) from any applied science, or generated inductively from clinical nursing practice. Alternatively, nurses may attempt to apply deductive theory (global theoretical frameworks) known as nursing models. In this paper, all theoretical approaches, irrespective of origin, are referred to as models used by nurses. Thirteen criteria by which clinicians, and others, can evaluate the clinical and practical utility of models used by nurses which are expressed in the form of questions are identified and discussed. The criteria are an extension, both in detail and in number, of those developed by Reynolds and Cormack and subsequently applied by those writers to the Johnson Behavioural System Model of Nursing. The value, or otherwise, of individual models, or of models in general, will not be discussed in this paper. However, the authors propose that if the evaluation criteria described here are applied to existing models, serious deficits will be identified in relation to their clinical and practical utility.  相似文献   
15.
When immunocompetent mice are inoculated with Borrelia burgdorferi, they develop acute arthritis and carditis that undergo spontaneous regression despite the persistence of infection. Specific T- and/or B-cell immunity appears to be necessary for resolution of disease manifestations. Humoral immune responses to B. burgdorferi are also important in prevention of B. burgdorferi infection, in that passive transfer of immune sera or protective monoclonal antibodies prevents the spirochete from establishing infection. It has previously been suggested that complement is necessary for effective antibody-mediated host responses against B. burgdorferi. To investigate the role of complement in the pathogenesis and prevention of Lyme disease, we compared the responses to B. burgdorferi challenge inoculation of mice genetically deficient in the fifth component of complement (C5) with those of C5-sufficient mice. All C5-deficient strains tested were susceptible to B. burgdorferi infection, and disease manifestations underwent regression in a similar time-course to those of complement-sufficient mice. Moreover, passive immunization of C5-deficient mice with either immune rabbit sera or neutralizing monoclonal antibody protected them from challenge infection. These results demonstrate that the expression of Lyme disease is not altered in mice deficient in C5 and that C5-mediated complement activation is not necessary for antibody-mediated protection from infection.  相似文献   
16.
Petit mal-grand mal (PM-GM) electroconvulsive therapy (ECT) is a technique developed by Impastato to elicit unconsciousness with a subconvulsive electrical stimulus, rather than with barbiturate anesthesia. Muscle relaxation is produced with succinylcholine chloride before stimulus is applied. The cases reported here illustrate applications of the technique to depressed patients with severe cardiac and pulmonary disease, and the use of PM-GM ECT in a patient in whom seizures could not be elicited by the usual ECT technique is described.  相似文献   
17.
Vaccination with recombinant outer surface protein A (OspA) has been shown to protect mice from infection with Borrelia burgdorferi, the Lyme disease agent. To determine whether antibodies to B. burgdorferi proteins other than OspA are involved in protective immunity, antibodies to OspA were removed from protective anti-B. burgdorferi serum; the residual serum was still protective. Absorption of OspA and OspB antibodies from anti-B. burgdorferi serum eliminated the protective effect. Therefore, active immunization experiments were performed to determine the roles of OspB and flagellin in protective immunity and to determine whether protective immunity induced by OspA is dose dependent. Active immunization with recombinant OspA protected mice from infection with an inoculum of 10(4) spirochetes, but this protection could be overcome with a challenge of 10(7) spirochetes; OspB protected mice from infection with an inoculum of 10(3) spirochetes but was insufficient to fully protect against 10(4) organisms; and immunization with flagellin had no protective effect. These studies suggest that OspA and OspB, but not flagellin, play roles in protective immunity to spirochete infection.  相似文献   
18.
Non-A, non-B viral hepatitis was transmitted to four colony-born chimpanzees by infusion of three lots of antihemophilic factor (factor VIII) implicated in the transmission of non-A, non-B hepatitis to two human recipients. All four inoculated animals showed histopathological evidence of viral hepatitis, and all demonstrated significant ALT elevations between seven and one-half weeks after inoculation. Acute-phase plasma from one of the infected chimpanzees (no. 771) was shown to induce non-A, non-B hepatitis in two other chimpanzees approximately three weeks after their inoculation. In addition, an acute-phase open liver wedge biopsy obtained from animal no. 771 was processed and examined by immune electron microscopy (IEM) for virus-like particles with convalescent serum from a serologically confirmed case of non-A, non-B hepatitis. Twenty-five to 30 nm (mean = 27 nm) diameter virus-like particles that were either "full" or "empty" were identified in this liver preparation by IEM. Two additional chimpanzees inoculated with a cesium chloride gradient fraction of an isopycnically banded liver homogenate (animal no. 771) also developed elevated ALT activity two to two and one-half weeks later. Our findings have experimentally verified that commercially produced factor VIII materials can induce non-A, non-B hepatitis in champanzees and that the disease can be subpassaged in these animals by inoculation of either acute-phase plasma or liver. These results also provide evidence for the association of 27 nm-diameter virus-like particles with non-A, non-B viral hepatitis.  相似文献   
19.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
20.
Increased sweat concentrations (92, 76 and 80 mEq/l) were observed in a 7-year-old boy with pitressin-resistant diabetes insipidus. All previous observations of elevated sweat electrolytes in diabetes insipidus have been in infants less than 10 months of age. The sweat test is an exceptionally reliable, sensitive and specific test for the diagnosis of Cystic Fibrosis. Pitressin-resistant diabetes insipidus is one of the diseases associated with elevated sweat test results.  相似文献   
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