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111.
OBJECTIVES: Herein we describe an additional case of myelolipoma of the adrenal gland, an uncommon tumor of the adrenal cortex, that had been incidentally discovered during abdominal US evaluation of the biliary tree. The clinical features, diagnosis and treatment of the condition are discussed. METHODS: Surgical treatment of the biliary tree and myelolipoma was performed through a Chevron transversal incision during the same surgical session. RESULTS: Surgery achieved good results and the postoperative course was unremarkable. CONCLUSIONS: Myelolipoma is a benign nonfunctioning tumor of the adrenal cortex comprised of adipose and hematopoietic tissue. It is usually asymptomatic and incidentally discovered during diagnostic evaluation for other pathologies. The diagnosis is made by US, CT and MRI. There is no agreement on whether surgical treatment is warranted.  相似文献   
112.
We present here some sensitive optical and mechanical experiments for monitoring the process of formation and growth of two-dimensional (2D) crystals of proteins on a lipid monolayer at an air-water interface. The adsorption of proteins on the lipid monolayer was monitored by ellipsometry measurements. An instrument was developed to measure the shear elastic constant (in plane rigidity) of the monolayer. These experiments have been done using cholera toxin B subunit (CTB) and annexin V as model proteins interacting with a monosialoganglioside (GM1) and dioleoylphosphatidylserine (DOPS), respectively. Electron microscopy observations of the protein-lipid layer transferred to grids were systematically used as a control. We found a good correlation between the measured in-plane rigidity of the monolayer and the presence of large crystalline domains observed by electron microscopy grids. Our interpretation of these data is that the crystallization process of proteins on a lipid monolayer passes through at least three successive stages: 1) molecular recognition between protein and lipid-ligand, i.e., adsorption of the protein on the lipid layer; 2) nucleation and growth of crystalline patches whose percolation is detected by the appearance of a non-zero in-plane rigidity; and 3) annealing of the layer producing a slower increase of the lateral or in-plane rigidity.  相似文献   
113.
BACKGROUND: Controversy exists regarding the effectiveness of propofol to prevent postoperative nausea and vomiting. This prospective, randomized, single-blinded study was designed to evaluate the antiemetic effectiveness of 0.5 mg/kg propofol when administered intravenously after sevoflurane- compared with desflurane-based anesthesia. METHODS: Two hundred fifty female outpatients undergoing laparoscopic cholecystectomy were assigned randomly to one of four treatment groups. All patients were induced with intravenous doses of 2 mg midazolam, 2 microg/kg fentanyl, and 2 mg/kg propofol and maintained with either 1-4% sevoflurane (groups 1 and 2) or 2-8% desflurane (groups 3 and 4) in combination with 65% nitrous oxide in oxygen. At skin closure, patients in groups 1 and 3 were administered 5 ml intravenous saline, and patients in groups 2 and 4 were administered 0.5 mg/kg propofol intravenously. Recovery times were recorded from discontinuation of anesthesia to awakening, orientation, and readiness to be released home. Postoperative nausea and vomiting and requests for antiemetic rescue medication were evaluated during the first 24 h after surgery. RESULTS: Propofol, in an intravenous dose of 0.5 mg/kg, administered at the end of a sevoflurane-nitrous oxide or desflurane-nitrous oxide anesthetic prolonged the times to awakening and orientation by 40-80% and 25-30%, respectively. In group 2 (compared with groups 1, 3, and 4), the incidences of emesis (22% compared with 47%, 53%, and 47%) and requests for antiemetic rescue medication (19% compared with 42%, 50%, and 47%) within the first 6 h after surgery were significantly lower, and the time to home-readiness was significantly shorter in duration (216 +/- 50 min vs. 249 +/- 49 min, 260 +/- 88 min, and 254 +/- 72 min, respectively). CONCLUSIONS: A subhypnotic intravenous dose of propofol (0.5 mg/kg) administered at the end of outpatient laparoscopic cholecystectomy procedures was more effective in preventing postoperative nausea and vomiting after a sevoflurane-based (compared with a desflurane-based) anesthetic.  相似文献   
114.
To evaluate the feasibility of nipple aspiration and to identify intermediate markers of breast cancer risk, nipple aspirate fluid (NAF) was collected from 177 subjects using a modified breast pump. The first 33 subjects demonstrated that we could obtain NAF quickly, reliably and repeatedly. Specimens from the remaining 144 subjects were collected to evaluate promising cellular biomarkers. NAF was obtained in 167 out of 177 (94%) subjects overall and in 99% of the 144 most recent subjects. Sufficient NAF was obtained to evaluate cytology in 160 out of 167 (96%) cases and specimens were sufficiently cellular to analyse DNA markers in 53% of cases. Among the last 144 subjects, menopausal status did not influence the ability to obtain NAF. NAF cytology correlated with increased breast cancer risk (P = 0.002). Using computerized image analysis of NAF epithelial cells, DNA index (P = 0.0002), percentage of cells in G2M (P = 0.05) and percentage of cells with hypertetraploidy (P = 0.002) increased as cytology became more abnormal. Our data indicate that NAF can be obtained in essentially all eligible subjects; that breast epithelial cells are evaluable in > 95% of NAF samples for cytology and in over half of NAF samples for DNA index (ploidy) and cell cycle analysis; and that abnormal NAF cytology correlates with increased breast cancer risk. This suggests that biomarkers identified in nipple aspirate fluid may prove useful either as an adjunct to currently accepted breast cancer screening methods, or to evaluate response to a chemopreventive agent.  相似文献   
115.
The solution structure of robustoxin, the lethal neurotoxin from the Sydney funnel-web spider Atrax robustus, has been determined from 2D 1H NMR data. Robustoxin is a polypeptide of 42 residues cross-linked by four disulphide bonds, the connectivities of which were determined from NMR data and trial structure calculations to be 1-15, 8-20, 14-31 and 16-42 (a 1-4/2-6/3-7/5-8 pattern). The structure consists of a small three-stranded, anti-parallel beta-sheet and a series of interlocking gamma-turns at the C-terminus. It also contains a cystine knot, thus placing it in the inhibitor cystine knot motif family of structures, which includes the omega-conotoxins and a number of plant and animal toxins and protease inhibitors. Robustoxin contains three distinct charged patches on its surface, and an extended loop that includes several aromatic and non-polar residues. Both of these structural features may play a role in its binding to the voltage-gated sodium channel.  相似文献   
116.
OBJECTIVE: To evaluate coagulation variables in 2 groups of dogs after tromethamine administration. ANIMALS: 13 Beagles. PROCEDURES: Both groups of dogs received a 30-minute IV infusion of 10 ml of 0.3M tromethamine/kg of body weight. In unsedated dogs (group 1, n = 8), prothrombin time, activated partial thromboplastin time, normalized ionized calcium concentration, platelet numbers, and platelet function were measured prior to treatment, at the end of the infusion, and 1 hour after the infusion. In xylazine-sedated dogs (group 2, n = 5), buccal mucosal bleeding time and plasma percentage of von Willebrand factor antigen were measured before and 1 hour after infusion, and fibrin degradation products concentration was measured 1 hour after infusion. Platelet function was assessed by determining platelet aggregation and by measuring ATP release from the aggregating platelets over 6 minutes, using a whole blood aggregometer, with 20, 10, and 5 microM ADP and 5 and 10 micrograms of collagen/ml as platelet activation agonists. RESULTS: There was no significant change in any of the variables measured in either group of dogs, compared with baseline values. CONCLUSIONS AND CLINICAL RELEVANCE: When administered to healthy dogs, tromethamine does not change the coagulation indices measured.  相似文献   
117.
PURPOSE: To report a case of Purtscher-like retinopathy after administration of retrobulbar anesthesia for an otherwise uncomplicated cataract extraction. METHOD: Case report. RESULTS: After cataract surgery with retrobulbar anesthesia, the patient followed a typical course of Purtscher-like retinopathy with an initial severe loss of vision followed by a gradual and nearly complete improvement in visual function. CONCLUSIONS: Purtscher-like retinopathy is uncommon after administration of retrobulbar anesthesia but had the same clinical course as other causes of this disorder.  相似文献   
118.
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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