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61.
Immunohistochemistry using monoclonal antibodies against human inhibin, a peptide hormone produced by ovarian granulosa cells to inhibit follicle-stimulating hormone (FSH), has been recently applied to diagnostic anatomic pathology. This investigation hypothesizes that inhibin immunohistochemistry will aid in the crucial clinical distinction between sex cord-stromal and other primary ovarian neoplasms. Available H&E slides and clinical information from a retrospective surgical series of 186 primary ovarian tumors were reviewed to verify diagnoses, and representative paraffin sections were immunostained with anti-inhibin (R1 monoclonal, Serotec, Kidlington, Oxford, UK). Immunoreactivity was graded as weak/strong (W/S), and the proportion of strong staining cells was coded as follows: S1 = <10%, S2 = 10%-50%, S3 = >50%, respectively. Inhibin immunoreactivity for 137 sex cord-stromal lesions was as follows: 100% of 66 granulosa cell tumors: 80% S3, 20% S2; 100% of 17 Sertoli-stromal tumors: 90% S3, 10% S2; 100% of 13 hyperplastic follicular/stromal lesions: 90% S3, 10% S2; 100% of six steroid cell tumors: 100% S3; 90% of 18 thecomas: 40% S3, 10% S2, 10% S1, 30% W; 0% of 12 fibromas, three myxomas, and two sclerosing stromal tumors. None (0 of 49) of the other ovarian neoplasms exhibited inhibin: 22 carcinomas, 12 carcinosarcomas, seven small cell carcinomas, six germ cell tumors, and two lymphomas. In the typical case, the distinction between sex cord-stromal and other ovarian neoplasms requires nothing more than routine pathological examination. In diagnostically challenging cases, our data indicate that inhibin immunohistochemistry is a very useful adjunct because granulosa and sertoli-stromal tumors are positive whereas other potential mimickers have been negative thus far.  相似文献   
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63.
OBJECTIVE: Increase of neutrophil chemotaxis in Beh?et's disease (BD) has been described, but it is not clear whether there is a correlation with other variables of neutrophil function and whether these modifications correlate with disease activity. METHODS: We studied neutrophil functions in patients with BD in the acute phase in comparison with healthy control subjects and with the same patients during disease remission, with or without therapy. We investigated in vivo neutrophil migration by Senn's skin window technique and measured adhesion assay and superoxide production in circulating and migrating neutrophils after different stimuli. RESULTS: Neutrophil migration in vivo was 101.3 +/- 17.9 x 10(6) polymorphonuclear lymphocytes (PMN)/cm2/24 h in patients with BD in the acute phase and 66.1 +/- 7.8 x 10(6) PMN/cm2/24 h in controls (p < 0.001). No correlation was found between leukocyte counts and neutrophil migration. Neutrophil migration evaluated in the same patients in a phase of disease remission was 58.3 +/- 10.3 x 10(6) PMN/cm2/24 h (p < 0.001 vs acute phase, not significant vs controls). The neutrophils of the exudate were normally primed to response to the chemotactic peptide fMLP. No differences between the 2 groups were found in superoxide production, adhesion under basal conditions, or in response to different stimuli by circulating and migrating neutrophils. CONCLUSION: Abnormally high migration of neutrophils in the active phase of BD is the only consistent neutrophil dysfunction. Since this modification is reversed by therapy, the evaluation of in vivo neutrophil migration may be useful in diagnosing and monitoring disease activity. Blood neutrophils have normal responses to different stimuli, indicating they are not primed by the disease state.  相似文献   
64.
The clinical significance of nuclear atypia in neurofibromas that lack necrosis or significant mitotic activity has not been systematically studied. We reviewed 14 neurofibromas from six patients with mild to marked nuclear atypia, with low mitotic activity in some tumors. Five tumors also had areas of increased cellularity consistent with cellular neurofibroma. Necrosis was absent. All patients were treated by conservative excision. Clinical follow-up, ranging from 8 months to 6 years, showed that none of the tumors recurred or metastasized. To further characterize these neoplasms, we assessed p53 expression, proliferation rate, and DNA content because these methods have been suggested by others as useful in differentiating benign from malignant nerve sheath tumors. p53 expression was detected by immunostaining in one tumor with 5% positive cells and in two tumors with rare positive cells (<1%). The remaining 11 tumors were negative. Tumor cell proliferation rate as determined by Ki-67 immunostaining showed <5% positive cells in 13 tumors. In one tumor, 10% of the cells were Ki-67 positive. Using flow cytometry methods and paraffin-embedded tissue, all tumors had diploid DNA content with an S phase fraction ranging from 5.2% to 18.2% (mean 9.4%). No significant differences were observed between the neurofibromas and cellular neurofibromas. For comparison, we studied three malignant peripheral nerve sheath tumors (MPNSTs). All MPNSTs had relatively high p53 (range 10-16%; mean 12%) and Ki-67 (range 32-42%; mean 38.0%) staining. One of the MPNSTs was aneuploid. The S phase fraction of the MPNSTs ranged from 8.1% to 51.8% (mean 28.6%). These results suggest that clinically benign neurofibromas, both usual and cellular types, can have significant cytologic atypia that can be accompanied by low mitotic activity. Conservative surgical excision for these tumors is adequate. The results of p53 and Ki-67 immunostaining and DNA content and S-phase analysis by flow cytometry support this interpretation. In addition, in tumors with borderline histologic findings, results of these ancillary studies may be useful in distinguishing benign from malignant nerve sheath tumors.  相似文献   
65.
We have designed a general protocol to assess the rate of replicon initiation in mammalian cells in the presence of inhibitors of DNA synthesis. It is based on cross-linking DNA in vivo with trioxsalen, which effectively blocks the movement of the replication forks along DNA, while having little effect on initiation of replication. We applied this protocol to study the effect of the plant amino acid mimosine on the rate of replicon initiation in exponentially growing murine erythroleukemia F4N cells. We found out that during the first 2 h after application of 25-400 microM mimosine, the initiation step was inhibited more efficiently than the overall DNA synthesis. In this respect, the effect of mimosine was similar to that of gamma-ray irradiation and differed from that of hydroxyurea and aphidicolin. The results suggest that in addition to inhibiting the elongation step of DNA synthesis, mimosine inhibits the initiation of DNA replication as well.  相似文献   
66.
Immunohistochemistry was used to evaluate the effects of neonatal handling and aversive stimulation during the first 10 days of life on the number of corticotrophs in the anterior lobe of the pituitary of 11-day-old male Wistar rats. Since adult rats handled during infancy respond with reduced corticosterone secretion in response to stressors and with less behavior inhibition in novel environments, we assumed that neonatal stimulation could affect pituitary morphology during this critical period of cell differentiation. Three groups of animals were studied: intact (no manipulation, N = 5), handled (N = 5) and stimulated (submitted to 3 different aversive stimuli, N = 5). The percentage of ACTH-immunoreactive cells in the anterior lobe of the pituitary (number of ACTH-stained cells divided by total number of cells) was determined by examining three slices per pituitary in which a minimum of 200 cells were counted by two independent researchers. Although animals during the neonatal period are less reactive to stress-like stimulation in terms of ACTH and corticosterone secretion, results showed that the relative number of ACTH-stained cells of neonatal handled (0.25 +/- 0.01) and aversive stimulated (0.29 +/- 0.03) rats was not significantly different from intact (0.30 +/- 0.03) animals. Neonatal stimulation may have a differential effect on the various subpopulations of corticotroph cells in the anterior pituitary.  相似文献   
67.
OBJECTIVES: To identify the predictors of perceived health and predictors of changes in perceived health in frail hospitalized older persons during the year after hospitalization. DESIGN: Both cross-sectional and longitudinal multivariate analysis of data from a cohort followed for 1 year. SETTING: Six hospital in a group practice model health maintenance organization (HMO) in Southern California. PARTICIPANTS: A total of 1889 persons aged 65 or older who met at least one of 13 inclusionary criteria for a randomized trial of Comprehensive Geriatric Assessment consultation at admission and completed three Functional and Health Status Questionnaires (FHSQ) during a 12-month period. MEASUREMENTS: Functional and health status measures included basic and intermediate activities of daily living (BADL and IADI) and social activities (SA) scales from the Functional Status Questionnaire as well as the mental health index (MHI) and current health perception (CHP), scales from the Medical Outcomes Study short from. Subject's severity of disease was measured by the Resource Demand Scale (RD Scale). RESULTS: In the cross-sectional analyses, MHI score, IADL score, RD Scale, history of falls during the 3 months before hospitalization, and female gender were significant predictors of perceived health in all models for each time point, BADL score, age, presence of incontinence, and ethnicity were significant in the model for baseline only, and SA score was significant in models for 3 months and 12 months only. In the longitudinal analyses, the baseline CHP score and the changes in MHI, IADL, and BADL score predicted CHP change from 0 to 3 months and from 3 to 12 months. CONCLUSIONS: Functional and psychosocial health indicators are the most important and most consistent predictors of perceived health. Our study showed that several predictors of perceived health in cross-sectional analysis did not predict changes in perceived health over a 1-year period. Hence, to fully understand the medical and social contributors to perceived health, a comprehensive approach using both cross-sectional and longitudinal analyses is necessary.  相似文献   
68.
5'-Deoxy-5'-(methylthio)adenosine (MTA), a key by-product of polyamine biosynthesis, is cleaved by MTA phosphorylase and is salvaged as adenine and, through conversion of the ribose moiety, methionine. An analog of MTA, 5'-deoxy-5'-(hydroxyethylthio)adenosine (HETA), is a substrate for trypanosome MTA phosphorylase and is active in vitro and in vivo against Trypanosoma brucei brucei, an agent of bovine trypanosomiasis. In this study, HETA and three O-acylated HETA derivatives were examined for their activities against model infections of T. b. brucei and Trypanosoma brucei rhodesiense, the agent of East African sleeping sickness. HETA was curative (>60%) for infections caused by 5 of 11 clinical isolates of T. b. rhodesiense when it was given to mice at 200 mg/kg of body weight for 7 days as a continuous infusion in osmotic pumps. HETA at 150 to 200 mg/kg also extended the life spans of the mice infected with four additional isolates two- to fivefold. Di- and tri-O-acetylated derivatives of HETA also proved curative for the infections, while a tri-O-propionyl derivative, although also curative, was not as effective. This study indicates that substrate analogs of MTA should be given important consideration for development as novel chemotherapies against African trypanosomiasis.  相似文献   
69.
With the aim of improving the nutritive value of an important grain legume crop, a chimeric gene specifying seed-specific expression of a sulfur-rich, sunflower seed albumin was stably transformed into narrow-leafed lupin (Lupinus angustifolius L.). Sunflower seed albumin accounted for 5% of extractable seed protein in a line containing a single tandem insertion of the transferred DNA. The transgenic seeds contained less sulfate and more total amino acid sulfur than the nontransgenic parent line. This was associated with a 94% increase in methionine content and a 12% reduction in cysteine content. There was no statistically significant change in other amino acids or in total nitrogen or total sulfur contents of the seeds. In feeding trials with rats, the transgenic seeds gave statistically significant increases in live weight gain, true protein digestibility, biological value, and net protein utilization, compared with wild-type seeds. These findings demonstrate the feasibility of using genetic engineering to improve the nutritive value of grain crops.  相似文献   
70.
To investigate the ionic actions of insulin in hypertension, 19F- and 31P-nuclear magnetic resonance spectroscopy were used to measure cytosolic free calcium (Ca(i)) and intracellular free magnesium (Mg(i)) levels in red blood cells from normal (n = 9) and hypertensive (n = 9) subjects before and 30, 60, 120, and 180 min after in vitro incubation with insulin. In hypertensive patients, basal Ca(i) levels were significantly higher (30.0 +/- 2.2 vs. 19.8 +/- 2.5 nmol/L; P < 0.05), and basal Mg(i) levels were significantly lower (170 +/- 10.9 vs. 209 +/- 8 micromol/L; P < 0.05) than in normotensive subjects. In normal cells, insulin significantly elevated Ca(i) to 39.8 +/- 8.0, 50.1 +/- 8.2, 69.3 +/- 11.1, and 50.9 +/- 13.4 nmol/L at 30, 60, 120, and 180 min and Mg(i) to 238 +/- 10,264 +/- 14,226 +/- 11, and 216 +/- 10 micromol/L at 30, 60, 120, and 180 min. In hypertensive subjects, the insulin-dependent Ca(i) elevation was blunted, and Mg(i) accumulation was completely suppressed. Continuous relationships were observed between basal values of each ion and insulin responses; the greater the Ca(i), the less the Ca(i) rose (r = -0.574; P = 0.013), and the lower the Mg(i), the less Mg(i) rose (r = 0.524; P = 0.025). Furthermore, a blunting of Mg(i) responses to insulin could be reproduced in normal cells that were magnesium depleted by prior treatment either with A23187 in a calcium-free medium or with high glucose concentrations (15 mmol/L). Once again, insulin responsiveness followed basal Mg(i) levels (r = 0.637; P < 0.001). Together, these data demonstrate ionic aspects of insulin resistance in hypertension and suggest that Ca(i) and Mg(i) levels may regulate cellular responsiveness to insulin. This may help to explain the different vascular actions attributed to insulin in normal compared with insulin-resistant states such as hypertension.  相似文献   
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