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91.
We report on some members of two unrelated families showing the characteristic features of Robinow syndrome. In a consanguineous Kuwaiti family, the index case with Robinow syndrome showed some unusual features including severe IUGR, laxity of ligaments, hyperextensible joints, redundant skin folds, severe normocytic anaemia, repeated infection, increased percentage of total T cells and CD4 positive population, reduced percentage of CD8 positive cells, and EMG abnormality. In a Pakistani family with a high degree of multigenerational consanguinity, a single case with the Robinow phenotype also had congenital heart disease, mainly involving the right side of the heart, with pulmonary stenosis, tricuspid atresia, ASD, VSD, double outlet right ventricle, and right atrial isomerism. This report suggests that the disease profile of Robinow syndrome may be extended to accommodate the unusual traits mentioned above. The association of the Robinow phenotype with congenital heart disease in case 2 of this report is consistent with the previously reported finding that congenital heart disease, particularly involving the right side of the heart, may be a prominent component of Robinow syndrome in a subset of patients.  相似文献   
92.
MANOVA and repeated measures ANOVA approaches have provided evidence of a number of limitations in several event-related potential (ERP) studies due to violations of their statistical assumptions and the typically moderate size of the available sample. Alternative, computer-intensive methods based on permutation principles have recently been developed. Up to now this methodology has focused mostly on magnitude differences between scalp distributions as measured by t statistics. In this paper the scope of permutation techniques in ERP analysis was widened. A new statistic (D statistic) is introduced to compare the shapes of scalp distributions of ERPs. Additionally a general non-parametric combinatory technique is introduced to evaluate, by means of multivariate permutation tests, several time points and/or recording sites in ERP data. The methodology described here was used to test if two ERP components elicited during word-pair matching tasks to semantic or phonological incongruences had different scalp distributions.  相似文献   
93.
The mechanism of uptake of human immunodeficiency virus-1 (HIV-1) into alveolar macrophages (AM), freshly isolated blood monocytes (MN), and cultured MN (CM) was investigated focusing on the role of CD4 and of surfactant-associated protein A (SP-A). By radioimmunoassay which obviated the problems of auto- and nonspecific fluorescence of more differentiated macrophages, each of the macrophage populations studied expressed CD4. Semiquantitative polymerase chain reaction was performed to assess uptake of HIV-1(JR-FL) into cells. OKT4a (directed against CD4) blocked uptake of HIV-1 into CM, AM, and MN by 67 to 100%. OKT4 (directed against another epitope of CD4) had a smaller and less consistent effect (0-90%), and control antibodies showed minimal effects and only at supersaturating concentrations. SP-A had no effect on uptake of HIV-1 into AM. SP-A also had no consistent effect on production of HIV-1(JR-FL) by AM infected in vitro (p24 antigen ELISA). Thus CD4 is the major receptor for HIV-1 in mononuclear phagocytes, including AM, and SP-A does not modulate entry.  相似文献   
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For the rapid genetic analysis of feline immunodeficiency virus (FIV), we developed a heteroduplex mobility assay (HMA) that utilizes a PCR-amplified fragment of the FIV envelope gene spanning the third and fourth variable regions of the envelope surface protein coding sequence. Viral sequences were successfully amplified from blood specimens from 98 naturally infected cats from Australia, Canada, Germany, Italy, South Africa, and the United States. Eighty were clearly assignable to the A or B envelope sequence subtypes. Three belonged to subtype C, one was dually infected with viruses harboring the A and B env subtypes, and several were categorized as outliers to any of the established subtypes or as probable intersubtype recombinants. Some geographic clustering was evident, with subtypes A and B found in greater frequency in the western and eastern regions of the United States, respectively. Subtypes A, B, and C were found on more than one continent, and countries with more than two samples analyzed contained at least two subtypes. The broadest representation of subtypes was found in Munich, Germany, where three subtypes and one virus that was not classifiable by HMA were found. Thirteen samples were selected for DNA sequence determination over the same region of env used for HMA. Analysis of all available FIV env sequences from this and previous studies revealed the existence of recombinant viruses generated from subtype A/B, B/D, and A/C envelope gene sequences. Subtype A env sequences were less diverse than subtype B sequences, although both groups had well-supported clusters. Furthermore, the mutational pattern giving rise to diversification in the two subtypes differed, with the subtype A viruses showing half as many synonymous site mutations compared to subtype B yet showing similar levels of nonsynonymous site changes. These results are consistent with the hypothesis that FIV-B is an older virus group and is possibly more host adapted than FIV-A.  相似文献   
96.
BACKGROUND: Previous studies in dogs showed that the phrenic nerve response to an acute hypoxic stimulus was dose dependently depressed by 0.5-2.0 minimum alveolar concentration (MAC) of halothane but not abolished. Because a carbon dioxide stimulus is transduced by a different mechanism in the carotid body chemoreceptors (CBCRs) than is a hypoxic stimulus, inhalational anesthetics may preferentially depress one of these transduction processes, the central neuronal processing, or both, of the integrated responses to these two types of inputs. METHODS: Carotid body chemoreceptor stimulation was produced by short (1-1.5 s), bilateral, 100% carbon dioxide in saline infusions into the carotid arteries during neural inspiration in unpremedicated, halothane-anesthetized, paralyzed, vagotomized dogs during constant mechanical ventilation. The phrenic neurogram quantified the neural inspiratory response. Four protocols were performed in the study: (1) the dose-dependent effects of halothane anesthesia (0.5-2.0 MAC) during hyperoxic hypercapnia on phrenic nerve activity, (2) the effects of three background levels of the partial pressure of carbon dioxide (PaCO2) on the magnitude of the carbon dioxide infusion responses at 1 MAC halothane, (3) the effects of anesthetic type on the magnitude of the carbon dioxide infusion response, and (4) the effects of CBCR denervation. RESULTS: Peak phrenic nerve activity (PPA) increased significantly during the carbon dioxide-stimulated phrenic burst in protocols 1-3; after denervation there was no response (protocol 4). Halothane produced a dose-dependent reduction in the PPA of control and carbon dioxide infusion-stimulated phrenic bursts and in the net carbon dioxide response. The net PPA responses for the different PaCO2 background levels were not different but were somewhat larger for sodium thiopental anesthesia than for 1.0 MAC halothane. CONCLUSIONS: The phrenic nerve response to an acute, severe carbon dioxide stimulus was dose dependently depressed by surgical doses of halothane. The observed responses to carbon dioxide infusion were mediated by the CBCRs because they were eliminated by CBCR denervation. These results suggest that the CBCR transduction and central transmission of the carbon dioxide signal in terms of inspiratory excitatory drive are not abolished at surgical levels of halothane anesthesia.  相似文献   
97.
The recently discovered tumor suppressor gene maspin has been shown to inhibit tumor cell motility, invasion, and metastasis in breast cancer by our laboratories. Nonetheless, the exploitation of maspin as a potential diagnostic and/or therapeutic tool has remained limited due to the lack of knowledge concerning its molecular and biological mechanism(s) of action. The work reported here demonstrates that recombinant maspin (rMaspin) has the ability to induce higher cell surface levels of alpha5- and alpha3-containing integrins and reduced levels of alpha2-, alpha4-, alpha6-, alpha(v)-, and some beta1-containing integrins in the metastatic human breast carcinoma cell line MDA-MB-435 concomitant with its ability to inhibit the invasive process in vitro. Furthermore, treatment of MDA-MB-435 cells with rMaspin results in the selective adhesion of the cell to a fibronectin matrix and conversion from a fibroblastic to a more epithelial-like phenotype. In addition, the ability of rMaspin to inhibit the invasive process can be abrogated with a blocking antibody to the alpha5beta1 integrin, which diminishes the ability of the cells to invade through a fibronectin matrix-containing barrier in vitro. Taken together, these data address the hypothesis that rMaspin reduces the invasive phenotype of MDA-MB-435 cells by altering their integrin profile, particularly alpha5, which in turn converts these cells to a more benign epithelial phenotype, with less invasive ability. These data provide new insights into the biological significance of this tumor suppressor gene found in normal mammary epithelium and may form the basis of novel therapeutic strategies in the management of breast carcinoma.  相似文献   
98.
Non-traumatic stereotyped postictal purpura is rare. A 25-year-old woman presented with right facial, cheek and periorbital purpuric eruptions that occurred after secondarily generalized tonic-clonic seizures. The stereotyped, invariably right-sided facial skin eruption, which resolved in 48 hours, falsely raised concerns of spousal abuse. Possible pathophysiological mechanisms include: (a) valsalva-induced capillary hypertension with secondary purpura, (b) ictal corticolimbic stimulation of the autonomic nervous innervation of facial vasomotor structures, and (c) trigeminal-mediated local release of vasoactive substances. Although rare, such stereotyped patterns of purpura should be recognized to avoid incorrect attribution of spousal abuse.  相似文献   
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100.
OBJECTIVE: To examine the effect of a clinical and administrative partnership with an academic urban Level I trauma center on the patient transfer practices at a suburban/rural Level II center. METHODS: Data for 2 years before affiliation (PRE) abstracted from inpatient charts and the trauma registry were compared with that for 2 years after (POST). The following data were collected: number of, reason for, and destination and demographics of transfers. Chi(2) test and t test analyses were used; p < 0.05 defined significance; data are mean +/- SEM. RESULTS: Transfer rate increased from 4% PRE to 6.9% (p = 0.001) POST with no significant difference in age, Glasgow Coma Scale score, Injury Severity Score, or Revised Trauma Score. Repatriation occurred in 12.8% POST (none PRE). The current Level I facility accepted 1.8% of all transfers PRE and 36.4% POST (p = 0.0001). PRE/POST rates by reason are as follows: pediatric, 14.6%/9.0% (p = 0.04); intensive care unit, 0.4%/1.7% (p = 0.13); complex orthopedic, 100%/0% (p = 0.005); vascular, 50%/0% (p = 0.008); spinal cord injury, 100%/100%; and ophthalmologic, 0%/100% (p = 0.005). CONCLUSIONS: In this experience of Level I/II partnership (1) transfer patterns were altered, (2) select patient cohort transfers decreased (pediatric, complex orthopedic, vascular), whereas others increased (aortic work-up), and (3) repatriation rates were low.  相似文献   
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