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991.
We report an epidemic of 16 cases of measles during pregnancy. The risk factors for such an association and the materno-fetal outcomes are presented. The mean age of the patients was 20.6 years, with a mean gravidity and parity of 2.1 and 1.1 respectively. The mean clinical features were: conjunctivitis, hyperthermia and cutaneous rash. Nine maternal complications occurred: 6 laryngitis and 3 pneumopathies. All patients were HIV negative. The outcomes of the pregnancy were the following: 2 abortions, 3 stillbirths, 1 preterm delivery and 2 full term births. Eight patients with ongoing pregnancies were lost to follow-up after their discharge from the hospital. We conclude on the need for a systematic prevention in exposed pregnant women by immunotherapy and in children by immunization.  相似文献   
992.
PURPOSE: To determine risk factors for secondary hemorrhage and poor visual outcome in children with traumatic hyphemas. METHODS: We reviewed 99 eyes of 97 children younger than 18 years who had been hospitalized for hyphema within 48 hours of blunt eye trauma. Inpatient records were examined for race, age, sickle cell trait status, size of hyphema and intraocular pressure at admission, secondary hemorrhage (rebleed of hyphema), and medications while hospitalized. Fifty-five eyes of 53 children had at least 1 month of follow-up or attained best-corrected visual acuity of 20/50 or better at their last outpatient visit. RESULTS: Among 99 eyes of 97 children with traumatic hyphema, secondary hemorrhage occurred in nine eyes (9%). Among 72 eyes of 70 African-American children, secondary hemorrhage occurred in nine eyes (14%), whereas in 27 eyes of 27 white children, there were no secondary hemorrhages. However, when the 14 eyes of 13 sickle cell trait-positive children were excluded from the African-American group, the 57 eyes of sickle cell trait-negative African-American and white children did not have any secondary hemorrhages. The sickle cell trait-positive group had secondary hemorrhages in nine of 14 eyes (64%), significantly (P < .005) different from the 0% rate in the 57 eyes of African-American sickle cell trait-negative and white children. The sickle cell trait-positive group also had higher intraocular pressure and permanent visual impairment. CONCLUSION: Sickle cell trait is a significant risk factor for secondary hemorrhage, increased intraocular pressure, and permanent visual impairment in children who have traumatic hyphemas following blunt trauma.  相似文献   
993.
BACKGROUND: The purpose of the study was to evaluate the evidence supporting the use of hypodermoclysis (i.e., subcutaneous infusion of fluids) to treat dehydrated elderly patients, and to discuss clinical applications of this mode of therapy in the long-term care setting. METHOD: Articles reporting the use of hypodermoclysis were identified using a systematic MEDLINE search between January 1966 and May 1996. Articles were included in our sample if they contained original patient data that evaluated either the efficacy or adverse effects associated with the use of subcutaneous infusions to treat dehydration in adults, whether hyaluronidase was required to facilitate the absorption of subcutaneous fluid, or if potassium could be added to the solution. RESULTS: Eighteen articles met the inclusion criteria. Since we hypothesized that adverse effects associated with hypodermoclysis may have been related largely to the use of nonelectrolyte or hypertonic solutions, the studies were evaluated according to the type of fluid administered. Six hundred and eighty-five patients were described in 13 studies evaluating the efficacy and toxicity of subcutaneously administered fluid. Four studies evaluated hypodermoclysis using electrolyte-containing solutions in 25 patients. Two of these were randomized control trials (RCT) that compared hypodermoclysis to intravenous therapy. Both reported similar absorption of fluids. In the single RCT that evaluated adverse effects, 4 of 17 patients receiving hypodermoclysis reported minor side effects similar to those reported with intravenous therapy. Adverse effects were more severe when electrolyte-free or hypertonic solutions were evaluated. Of the 639 patients who may have received electrolyte-free solutions, 16 patients (2.5%) reported adverse effects, 8 of which were severe. Both patients reported to have received hypertonic solutions noted adverse effects, one of which was severe. The use of hyaluronidase to facilitate absorption was evaluated in 74 patients. These studies suggest that hyaluronidase improves the speed of fluid absorption but may not change the patient's comfort level. A single case report of 350 subcutaneous infusions in 67 patients investigated the administration of up to 34 mmol/L of potassium chloride (KCl) by hypodermoclysis. The only adverse reaction observed was discomfort at the infusion site. CONCLUSIONS: Hypodermoclysis can be used to most safely provide fluids when electrolyte-containing fluids are administered. Hypodermoclysis may have fallen into disuse because of reports of severe adverse reactions related to infusions of electrolyte-free or hypertonic solutions that would likely be considered inappropriate today. Whether or not hyaluronidase is required to promote subcutaneous fluid absorption remains unresolved. Limited evidence suggests that potassium chloride may, with caution, be safely added to subcutaneous infusions. The majority of the available studies evaluating hypodermoclysis are of poor quality. Because of the tremendous potential benefits of administering fluid subcutaneously, there is a need for good quality studies to evaluate the efficacy of hypodermoclysis.  相似文献   
994.
995.
A duplication of a 1.5-Megabase genomic region encompassing the gene for the peripheral myelin protein 22 (PMP22) is found on chromosome 17p11.2-12 in Charcot-Marie-Tooth disease type 1A (CMT1A), whereas the reciprocal deletion is associated with hereditary neuropathy with liability to pressure palsies (HNPP). Since most CMT1A patients harbor three copies of the PMP22 gene, and most HNPP patients carry only a single copy, a gene dosage effect has been proposed as a mechanism for both diseases. We have analyzed the steady-state expression of PMP22 protein in sural nerve biopsies from three CMT1A and four HNPP patients. Quantitative immunohistochemical determination showed that PMP22 protein expression relative to that of myelin protein zero and myelin basic protein was increased in all CMT1A patients and reduced in all HNPP patients, as compared with biopsy samples of patients with normal PMP22 gene expression. These data demonstrate that both neuropathies result from an imbalance of PMP22 protein expression.  相似文献   
996.
In a recent study by Ellason and Ross, patients with Dissociative Identity Disorder reported a decrease in symptoms on the Millon Clinical Multiaxial Inventory-II over a 2-yr. follow-up period. Patients judged to have achieved integration of their personalities rated themselves as more substantially improved on the Millon-II than did patients judged not to have achieved integration. Ellason and Ross suggested that this improvement reflected the influence of treatment; however, for several reasons, their findings are open to alternative interpretations. First, in the absence of proper control conditions, one cannot rule out the contribution of other factors to the over-all improvement of patients such as regression of symptoms toward the mean following the initial assessment. Second, patients self-reported improvement was less substantial when data were reanalyzed using more appropriate statistical criteria. Third, the greater improvement observed among integrated patients relative to nonintegrated patients may reflect influences other than differential responsiveness to treatment, such as less severe pathology prior to treatment. More systematic research is needed to clarify the effect of treatment on Dissociative Identity Disorder.  相似文献   
997.
998.
We have created two sets of substitution mutations in the Moloney murine leukemia virus (Mo-MuLV) matrix protein in order to identify domains involved in association with the plasma membrane and in incorporation of the viral envelope glycoproteins into virus particles. The first set of mutations was targeted at putative membrane-associating regions similar to those of the human immunodeficiency virus type 1 matrix protein, which include a polybasic region at the N terminus of the Mo-MuLV matrix protein and two regions predicted to form beta strands. The second set of mutations was created within hydrophobic residues to test for the production of virus particles lacking envelope proteins, with the speculation of an involvement of the membrane-spanning region of the envelope protein in incorporation into virus particles. We have found that mutation of the N-terminal polybasic region redirected virus assembly to the cytoplasm, and we show that tryptophan residues may also play a significant role in the intracellular transport of the matrix protein. In total, 21 mutants of the Mo-MuLV matrix protein were produced, but we did not observe any mutant virus particles lacking the envelope glycoproteins, suggesting that a direct interaction between the Mo-MuLV matrix protein and envelope proteins either may not exist or may occur through multiple redundant interactions.  相似文献   
999.
In this study, we demonstrate that: (i) injection of an adenovirus (Ad) vector containing the brain-derived neurotrophic factor (BDNF) gene (Ad.BDNF) into the vitreous chamber of adult rats results in selective transgene expression by Müller cells; (ii) in vitro, Müller cells infected with Ad.BDNF secrete BDNF that enhances neuronal survival; (iii) in vivo, Ad-mediated expression of functional BDNF by Müller cells, temporarily extends the survival of axotomized retinal ganglion cells (RGCs); 16 days after axotomy, injured retinas treated with Ad.BDNF showed a 4.5-fold increase in surviving RGCs compared with control retinas; (iv) the transient expression of the BDNF transgene, which lasted approximately 10 days, can be prolonged with immunosuppression for at least 30 days, and such Ad-mediated BDNF remains biologically active, (v) persistent expression of BDNF by infected Müller cells does not further enhance the survival of injured RGCs, indicating that the effect of this neurotrophin on RGC survival is limited by changes induced by the lesion within 10-16 days after optic nerve transection rather than the availability of BDNF. Thus, Ad-transduced Müller cells are a novel pathway for sustained delivery of BDNF to acutely-injured RGCs. Because these cells span the entire thickness of the retina, Ad-mediated gene delivery to Müller cells may also be useful to influence photoreceptors and other retinal neurons.  相似文献   
1000.
Campylobacter jejuni with Gm1 ganglioside in the core of its lipopolysaccharide has been associated with Guillain-Barré syndrome. Since this epitope may be of considerable pathophysiologic importance and since this ganglioside binds cholera toxin, a rapid screening assay to detect bacteria that bind cholera toxin as an indication of Gm1 on their surfaces was developed. In the assay, bacterial lawns were grown on agar plates, harvested with phosphate-buffered saline, boiled, and incubated with a standard concentration of cholera B subunit. Preparations from strains with Gm1 were observed to inhibit the binding of cholera B subunit to Gm1 in a microtiter enzyme-linked immunosorbent assay. By using this assay with two groups of strains, 37 positive strains were detected among the 197 tested. Species with positive isolates included C. jejuni, Campylobacter coli, and Helicobacter pylori. The assay is capable of testing large numbers of isolates and should prove useful in future clinical and epidemiological studies of bacteria with this epitope.  相似文献   
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