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91.
BACKGROUND: Pap smear screening studies in STD clinics have reported high rates of squamous intraepithelial lesions (SIL); however, there are limited data on levels of unsatisfactory smears of characteristics associated with cytologic abnormalities. GOAL: To assess the yield to Pap smear screening in an STD clinic and to evaluate the rates of and risk factors for atypia, low-grade SIL (LSIL), and high-grade SIL (HSIL). STUDY DESIGN: A chart review of the clinic records of women undergoing Pap smear screening between 1991 and 1994 was conducted. Results were assessed from two different screening protocols, the first using a Dacron swab to obtain the endocervical sample and the second using a cytobrush. RESULTS: Of 2034 Pap smears, 1313 (64.6%) were negative, 202 (9.9%) were unsatisfactory, 257 (12.6%) were atypical, 211 (10.4%) had LSIL, and 51 (2.5%) had HSIL. With the change to the cytobrush protocol, the rate of unsatisfactory smears decreased from 14.4% to 3% (p < 0.001), atypia increased from 10% to 16.7% (p < 0.001), and HSIL rose from 1.7% to 3.7% (p < 0.001). By multivariate analysis, atypia was associated with genital warts (odds ratio (OR) 1.53, 95% confidence interval (CI): 1.16-2.02); LSIL with younger age (p < 0.001, for trend), black race (OR 1.51, 95% CI: 1.08-2.10), genital warts (OR 1.81, 95% CI: 1.33-2.47), and an abnormal appearance of the cervix on examination (OR 2.49, 95% CI: 1.85-3.35); and HSIL with a previous abnormal Pap smear (OR 2.48, 95% CI: 1.08-2.10). Overall, abnormality rates were significantly higher in adolescents (35.5%) than older women (21.7%) (p < 0.01). CONCLUSIONS: Obtaining satisfactory Pap smears among women undergoing screening in an STD clinic is feasible and cytologic abnormalities are common. These results continue to support the need for Pap smear screening in STD clinics, but the high rates in adolescents, a group in whom the natural history of cytologic abnormalities has not been well-defined, raise questions about the need to develop age-appropriate screening and management strategies.  相似文献   
92.
Previously, we have demonstrated that phagocytosis of IgG1-coated particles by macrophages in vitro is impaired by deletion of Fc gamma RIII in mice, suggesting that IgG1 may interact preferentially with Fc gamma RIII. In the present study, the biologic relevance of this observation was addressed by triggering various effector functions of the immune system in Fc gamma RIII(-/-) mice, using panels of mAbs of different IgG subclasses. Both binding and phagocytosis of IgG1-coated sheep or human erythrocytes by Fc gamma RIII(-/-) macrophages in vitro were strongly impaired, indicating that the impaired ingestion of complexed IgG1 by Fc gamma RIII(-/-) macrophages is due to a defect in binding. An in vivo consequence of the defective phagocytosis was observed by resistance of Fc gamma RIII-deficient mice to experimental autoimmune hemolytic anemia, as shown by a lack of IgG1-mediated erythrophagocytosis in vivo by liver macrophages. Furthermore, trapping of soluble IgG1-containing immune complexes by follicular dendritic cells in mesenteric lymph nodes from Fc gamma RIII(-/-) mice was abolished. Whole blood from Fc gamma RIII(-/-) mice was unable to induce lysis of tumor cells in the presence of IgG1 antitumor Abs. Finally, IgG1 mAbs proved unable to mount a passive cutaneous anaphylaxis in Fc gamma RIII(-/-) mice. Together, these results demonstrate that IgG1 complexes, either in particulate or in soluble form, trigger in vitro and in vivo immune effector functions in mice predominantly via Fc gamma RIII.  相似文献   
93.
BACKGROUND: Some patients who undergo cerebral aneurysm surgery require cardiopulmonary bypass and deep hypothermic circulatory arrest. During bypass, these patients often are given large doses of a supplemental anesthetic agent in the hope that additional cerebral protection will be provided. Pharmacologic brain protection, however, has been associated with undesirable side effects. These side effects were evaluated in patients who received large doses of propofol. METHODS: Thirteen neurosurgical patients underwent cardiopulmonary bypass and deep hypothermic circulatory arrest to facilitate clip application to a giant or otherwise high-risk cerebral aneurysm. Electroencephalographic burst suppression was established before bypass with an infusion of propofol, and the infusion was continued until the end of surgery. Hemodynamic and echocardiographic measurements were made before and during the prebypass propofol infusion and again after bypass. Emergence time also was determined. RESULTS: Prebypass propofol at 243 +/- 57 micrograms.kg-1.min-1 decreased vascular resistance from 34 +/- 8 to 27 +/- 8 units without changing heart rate, arterial or filling pressures, cardiac index, stroke volume, or ejection fraction. Propofol blood concentration was 8 +/- 2 micrograms/ml. Myocardial wall motion appeared hyperdynamic at the end of cardiopulmonary bypass, and all patients were weaned therefrom without inotropic support. After bypass, vascular resistance decreased further, and cardiovascular performance was improved compared to baseline values. Nine of the 13 patients emerged from anesthesia and were able to follow commands at 3.1 +/- 1.4 h. Three others had strokes and a fourth had cerebral swelling. CONCLUSIONS: Propofol infused at a rate sufficient to suppress the electroencephalogram does not depress the heart or excessively prolong emergence from anesthesia after cardiopulmonary bypass and deep hypothermic circulatory arrest.  相似文献   
94.
OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included.  相似文献   
95.
A polymerase chain reaction (PCR) method for the rapid diagnosis of tuberculous meningitis (TBM) was used to study prospectively 47 cerebrospinal fluid (CSF) samples from 45 patients. Twenty CSF samples were from patients with clinically suspected TBM and another 27 samples came from patients without clinically suspected TBM. Mycobacterial DNA was detected in 15 CSF samples (14 from patients with clinically suspected TBM and 1 from a patient not suspected of having TBM). Of the PCR-positive samples, 4 were also positive for mycobacterial culture. However, 32 PCR-negative samples were all culture-negative. All samples were negative for the acid-fast bacillus by direct smear. The single PCR-positive patient in the clinically unsuspected TBM group was initially diagnosed as suffering from aseptic meningitis on the basis of his clinical features. The mycobacterial culture of his CSF specimen was also positive and a revised diagnosis of an aseptic type of TBM was made. The estimations of specificity and sensitivity in this study were 100% and 70% respectively. The results showed that using a PCR to detect mycobacterial DNA in CSF for the early diagnosis of TBM is not only a rapid but also an accurate method.  相似文献   
96.
97.
Janus tyrosine kinase (JAK) has recently been linked to signal transduction by cytokine receptors of the hematopoietin family. We have recently described a 116-kDa tyrosine kinase (p116) present in interleukin-2 (IL-2) receptor complexes in human YT cells that showed functional characteristics of a JAK kinase. These included receptor association, rapid and transient tyrosine phosphorylation kinetics in response to ligand, and in vitro autophosphorylating tyrosine kinase activity (Kirken, R. A., Rui, H., Evans, G. A., and Farrar, W. L. (1993) J. Biol. Chem. 268, 22765-22770). Here we extend these observations by demonstrating structural homologies between IL-2-modulated p116 and prolactin-modulated JAK2 in the rat T cell line Nb2. These include similar net charge as determined by nonequilibrium pH gradient electrofocusing and related primary structure based upon phosphopeptide mapping of V8 protease-digested hyperphosphorylated proteins. This putative JAK kinase underwent marked tyrosine phosphorylation in response to IL-2, IL-4, and IL-7, lymphoid growth factors that use the common IL-2 receptor gamma-chain, but not in response to prolactin. Furthermore, polyclonal antisera to JAK1, JAK2, or tyrosine kinase 2 did not recognize either rat or human p116. However, we identified the IL-2-modulated p116 as the recently cloned novel leukocyte Janus kinase, L-JAK, using an antiserum to a peptide corresponding to the COOH terminus of human L-JAK.  相似文献   
98.
PURPOSE: To determine the maximum-tolerated dose (MTD) of iodine 131 (131I)-labeled 81C6 monoclonal antibody (mAb) in brain tumor patients with surgically created resection cavities (SCRCs) and to identify any objective responses to this treatment. METHODS: In this phase I trial, eligible patients were treated with a single injection of 131I-labeled 81C6. Cohorts of three to six patients were treated with escalating dosages of 131I (starting dose of 20 mCi with a 20-mCi escalation in subsequent cohorts) administered through an Ommaya reservoir in the SCRC. Patients were followed up for toxicity and response until death or for a minimum of 1 year after treatment. The SCRC patients, who were previously irradiated, were followed up without additional treatment unless progressive disease was identified. RESULTS: We administered 36 treatments of 131I doses up to 120 mCi to 34 previously irradiated patients with recurrent or metastatic brain tumors. Dose-limiting toxicity was reached at 120 mCi and was limited to neurologic or hematologic toxicity. None of the patients treated with less than 120 mCi developed significant neurologic toxicity; one patient developed major hematologic toxicity (MHT). The estimated median survival for patients with glioblastoma multiforme (GBM) and for all patients was 56 and 60 weeks, respectively. CONCLUSION: The MTD for administration of 131I-labeled 81C6 into the SCRCs of previously irradiated patients with recurrent primary or metastatic brain tumors was 100 mCi. The dose-limiting toxicity was neurologic toxicity. We are encouraged by the minimal toxicity and survival in this phase I trial. Radiolabeled mAbs may improve the current therapy for brain tumor patients.  相似文献   
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