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91.
Light and electron microscopic techniques were used to study the morphometry and dynamic changes of macrophages in the postnatal and sex hormone-treated chicken oviduct, respectively. Abundant typical macrophages, containing clear vacuoles, well-developed mitochondria, Golgi complexes and lysosomal bodies in their cytoplasms, were observed in the lamina propria of all segments of the postnatal chicken oviduct, occurring more frequently in the vaginal part. When 7-day-old chickens were injected with diethylstilbestrol (DES), and DES plus progesterone, infiltration of a significant number of macrophages in both groups, but not in controls could be seen. The light and electron microscopic structures of the macrophages in both postnatal and sex hormone-treated chicken oviduct were similar. These results show that typical macrophages are present in the chicken oviduct; their frequency of occurrence varies with different oviductal segments, and they are influenced by sex hormones.  相似文献   
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Humoral responses to a protein require T-B cell communication for B cell activation by T cells. Previous studies from this laboratory have mapped the T and B cell recognition sites (epitopes) on sperm-whale myoglobin (Mb) and several other proteins. It was found that, five of six regions on Mb recognized by T cells are also recognized by B cells (i.e. antibodies). There is, however, one region (E6) residing within Mb residues 61-77, that is recognized only by T cells and to which no antibody (Ab) responses are detectable. To investigate the function of this exclusive T cell epitope, we established, from E6-primed BALB/c mice, an E6-specific T cell line (T(e6)) which comprised Th2-type cells. These T cells provided help in vitro to B cells from Mb-primed BALB/c mice and activated them to produce anti-Mb Abs of the IgM (58.2%) and IgG (41.8%) isotypes. The helper activity of T(e6) cells was dependent on the concentration of the challenging Ag (intact Mb or peptide E6) in culture. Action of soluble factors released from E6-activated T(e6) cells on B(mb) cells led to low production of anti-Mb Abs, suggesting that activation of the B cells was more dependent on their contact with T cells. Mapping of the epitope recognition of the anti-Mb Abs produced in vitro by B(mb) cells on activation by T(e6) revealed that this activation was not general to all antigenic regions recognized by anti-Mb Abs in BALB/c mice. E6-specific T cells caused in vitro activation and differentiation of B(mb) cells into plasma cells that secreted anti-Mb Abs directed, in decreasing order, against the following Mb regions: E4 (107-120) > E3 (87 - 100) > E1 (10 - 22). Little or no Ab responses could be detected against peptides E2 (50 - 62), E5 (141 - 153) and E6 (61 - 77). With B cells of peptide-primed BALB/c mice, T(e6) cells activated strongly E4-, E3- or E1, and only very slightly E2- or E6-, primed B cells to secrete Abs against the correlate peptide, but failed completely to activate E5-primed B cells. The results show that a protein T cell epitope, to which no Abs are detectable, plays an active role in B cell responses against other epitopes within the same protein.  相似文献   
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Sporadic Creutzfeldt-Jakob disease (CJD) with 129M/M, and iatrogenic and familial CJD with E200K and M232R, showed similar clinicopathologic features, a synaptic type deposition of PrPCJD, and high transmission frequencies to mice. Sporadic patients with 129M/V or 129V/V, and mutation cases with V180I, showed slightly different features and low or null transmission frequencies to mice. Hereditary cases with P102L, P105L, A117V, Y145stop, and insertions had different features but all demonstrated a long clinical duration and the presence of PrP plaques. The experimental transmission to mice of these mutant forms was difficult, except for one-third of the cases with P102L. CJD and related diseases, even those that are hereditary, may thus be divided into two different groups, those that are easily transmissible and those that are either difficult to transmit or nontransmissible.  相似文献   
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OBJECTIVE: To examine the hypothesis that an association exists between severe asthma and familial affective and anxiety disorders. METHOD: A parent, usually the mother, of 62 adolescents admitted to a tertiary care asthma center was administered the Family History-Research Diagnostic Criteria Interview. Lifetime prevalence rates of psychiatric disorders in first-degree relatives were compared with previously reported rates. RESULTS: In relatives of asthmatic adolescents, rates for depression, mania (females only), substance abuse (males only), and antisocial personality disorder were significantly higher than the rates in the non-ill comparison sample. Rates for substance abuse (males only) and antisocial personality disorder were higher than the rates for relatives of the depressed comparison sample. Rates for anxiety disorders were not higher than rates in epidemiological samples. Rates of attention-deficit hyperactivity disorder (females only) and posttraumatic stress disorder in relatives were higher than in community samples. CONCLUSIONS: These results support the presence of a link between severe asthma and familial affective disorders, posttraumatic stress disorder, antisocial personality disorder, and substance abuse. Whether these disorders are genetically associated with asthma or represent an association with severe asthma because of environmental effects on the growing child is discussed.  相似文献   
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We previously demonstrated that in mice transgenic for genes coding for an anti-ssDNA autoantibody B cells were functionally inactivated but not physically deleted. We have now extended this model by introducing an arginine into the CDR2 of the heavy chain transgene. This change alters the specificity of the Ab from anti-ssDNA to anti-dsDNA and increases the affinity for ssDNA. Mice carrying this transgene displayed a significant reduction of peripheral B cells and anti-dsDNA B cells were not recovered from the spleens. The remaining B cells escape deletion by revising their Ag receptors in several ways: 1) elimination of the transgenic heavy chain gene via intrachromosomal recombination, followed by rearrangement and expression of endogenous VH genes; 2) ongoing rearrangement of endogenous kappa light chain genes to generate a non-dsDNA-binding Ab; and 3) expression of a rare V lambda gene, V lambda x, to generate a non-DNA-binding Ab.  相似文献   
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OBJECTIVE: To determine whether physiological severity of asthma is associated with increased psychological symptoms in children. METHOD: Participants were 337 children, aged 7 to 19 years (mean 11.9, SE 0.13), and a parent of each child. Children's asthma severity was rated by experienced pediatric asthma specialists using current guidelines from the National Heart, Lung, and Blood Institute. Children filled out the Children's Manifest Anxiety Scale and the Weinberger Adjustment Inventory. Parents reported on their child's medical history, completed the Child Behavior Checklist (CBCL) about their child, and completed the Pennebaker Inventory of Linguid Languidness as a measure of their own physical symptoms. RESULTS: Child-rated anxiety symptoms were unrelated to asthma severity or to markers of asthma functional morbidity. Parental ratings of internalizing symptoms in their children were related to severity. Parent physical symptoms explained 10.2% of the variance in CBCL Internalizing symptoms, and asthma severity added an additional 6.7% to the variance. CONCLUSIONS: Asthma severity may be a more salient stressor to parents, who in turn report higher levels of child internalizing symptoms for children with severe asthma, than to children themselves. Contrary to prior hypotheses, children with severe asthma did not rate themselves as having higher levels of anxiety than those with mild or moderate asthma or than standardized norms.  相似文献   
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