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91.
Retroperitoneal venous hemangioma is a very rare condition. Only two cases have been reported in the English literature. We report the case of a 28-yr-old man with a retroperitoneal venous hemangioma who underwent surgical resection. Preoperative magnetic resonance imaging revealed a retroperitoneal tumor with low signal intensity on the T1-weighted image and high signal intensity on the T2-weighted image, typical of hemangiomas. In addition, it showed a partial interruption of the muscle layer surrounding the tumor. Intraoperative findings showed a large, reddish brown retroperitoneal mass with an ill defined capsule firmly attached to the muscular tissue surrounding the tumor. Retroperitoneal hemangioma is rare and is almost always of the cavernous type. Although accurate pre- and intraoperative diagnosis of retroperitoneal venous hemangiomas is difficult, magnetic resonance imaging and the presence of a firm attachment to the muscles may be helpful for the important diagnostic findings of this disease.  相似文献   
92.
BACKGROUND: Survival of post-myocardial infarction patients is related inversely to their levels of very-low-frequency (0.003 to 0.03 Hz) RR-interval variability. The physiological basis for such oscillations is unclear. In our study, we used blocking drugs to evaluate potential contributions of sympathetic and vagal mechanisms and the renin-angiotensin-aldosterone system to very-low-frequency RR-interval variability in 10 young healthy subjects. METHODS AND RESULTS: We recorded RR intervals and arterial pressures during three separate sessions, with the patient in supine and 40 degree upright tilt positions, during 20-minute frequency (0.25 Hz) and tidal volume-controlled breathing after intravenous injections: saline (control), atenolol (0.2 mg/kg, beta-adrenergic blockade), atropine sulfate (0.04 mg/kg, parasympathetic blockade), atenolol and atropine (complete autonomic blockade), and enalaprilat (0.02 mg/kg, ACE blockade). We integrated fast Fourier transform RR-interval spectral power at very low (0.003 to 0.03 Hz), low (0.05 to 0. 15 Hz), and respiratory (0.2 to 0.3 Hz) frequencies. Beta-adrenergic blockade had no significant effect on very-low- or low-frequency RR-interval power but increased respiratory frequency power 2-fold. ACE blockade had no significant effect on low or respiratory frequency RR-interval power but modestly (approximately 21%) increased very-low-frequency power in the supine (but not upright tilt) position (P<0.05). The most profound effects were exerted by parasympathetic blockade: Atropine, given alone or with atenolol, abolished nearly all RR-interval variability and decreased very-low-frequency variability by 92%. CONCLUSIONS: Although very-low-frequency heart period rhythms are influenced by the renin-angiotensin-aldosterone system, as low and respiratory frequency RR-interval rhythms, they depend primarily on the presence of parasympathetic outflow. Therefore the prognostic value of very-low-frequency heart period oscillations may derive from the fundamental importance of parasympathetic mechanisms in cardiovascular health.  相似文献   
93.
The bacteria isolated from the patients with lower respiratory tract infections were collected by institutions located throughout Japan, since 1981. Ikemoto et al. have been investigating susceptibilities of these isolates to various antibacterial agents and antibiotics, and characteristics of the patients and isolates from them each year. Results obtained from these investigations are discussed. In 16 institutions around the entire Japan, 557 strains of presumably etiological bacteria were isolated mainly from the sputa of 449 patients with lower respiratory tract infections during the period from October 1996 to September 1997. MICs of various antibacterial agents and antibiotics were determined against 98 strains of Staphylococcus aureus, 93 strains of Streptococcus pneumoniae, 84 strains of Haemophilus influenzae, 84 strains of Pseudomonas aeruginosa (non-mucoid strains), 17 strains of Pseudomonas aeruginosa (mucoid strains), 31 strains of Moraxella subgenus Branhamella catarrhalis, 21 strains of Klebsiella pneumoniae etc., and the drug susceptibilities of these strains were assessed except for those strains that died during transportation. 1) S. aureus S. aureus strains for which MICs of oxacillin (MPIPC) were higher than 4 micrograms/ml (methicillin-resistant S. aureus) accounted for 67.3%. The frequency of the drug resistant bacteria increased comparing to the previous year's 52.7%. Arbekacin (ABK) and vancomycin (VCM) showed the highest activities against both S. aureus and MRSA with MIC80s of 1 microgram/ml. 2) S. pneumoniae Imipenem (IPM) and panipenem (PAPM) of carbapenems showed the most potent activities with MIC80s of 0.063 microgram/ml. Faropenem (FRPM) showed the next potent activity with MIC80 of 0.125 microgram/ml. The other drugs except erythromycin (EM), clindamycin (CLDM) and tetracycline (TC) were active against S. pneumoniae tested with MIC80s of 8 micrograms/ml or below. 3) H. influenzae The activities of all drugs were potent against H. influenzae tested with MIC80s of 4 micrograms/ml or below. Cefotiam (CTM), cefmenoxime (CMX), cefditoren (CDTR) and ofloxacin (OFLX) showed the most potent activities with MIC80s of 0.063 microgram/ml. 4) P. aeruginosa (mucoid strains) Tobramycin (TOB) showed the most potent activity against P. aeruginosa (mucoid strains) with MIC80 of 1 microgram/ml. Ceftazidime (CAZ), cefsulodin (CFS), IPM, gentamicin (GM), ABK and ciprofloxacin (CPFX) showed the next potent activities, with MIC80s of 2 micrograms/ml. The MIC80s of the other drugs ranged from 4 micrograms/ml to 16 micrograms/ml. 5) P. aeruginosa (non-mucoid strains) TOB and CPFX showed the most potent activities against P. aeruginosa (non-mucoid strains) with MIC80s of 1 microgram/ml. The MIC80s of piperacillin (PIPC) and cefoperazone (CPZ) were 16 micrograms/ml in 1995, and they were 64 micrograms/ml in 1996. 6) K. pneumoniae All drugs except ampicillin (ABPC) were active against K. pneumoniae. CMX, cefpirome (CPR), cefozopran (CZOP) and carumonam (CRMN) showed the most potent activities against K. pneumoniae with MIC80s of 0.125 microgram/ml. The MIC80s of the other drugs ranged from 0.25 microgram/ml to 2 micrograms/ml. 7) M.(B) catarrhalis Against M.(B.) catarrhalis, all drugs showed good activities with MICs of 4 micrograms/ml or below. IPM and minocycline (MINO) showed the most potent activities with MICs of 0.063 microgram/ml. Also, we investigated year to year changes in the characteristics of patients, their respiratory infectious diseases, and the etiology. Patients' backgrounds were examined for 557 isolates from 449 cases. The examination of age distribution indicated that the proportion of patients with ages over 60 years was 71.0% of all the patients showing a slight increase over that in 1994. Proportions of diagnosed diseases were as follows: Bacterial pneumonia and chronic bronchitis were the most frequent with 35.9% and 30.3% respectively. They were followed by bronchiectasis with a proportion of 10.  相似文献   
94.
Oligosaccharides, especially mannose residues, expressed on the cell surface, are thought to be important for virus-induced membrane fusion. We examined the effect of mannose-binding compounds, pradimicin derivative BMY-28,864 (PRM) and concanavalin A (Con A), on cell fusion of human parainfluenza type 2 virus (hPIV2)-infected HeLa cells. Syncytium formation of hPIV2-infected HeLa cells was suppressed in the presence of Con A. On the other hand, PRM enhanced cell fusion of hPIV2-infected HeLa cells. These effects were blocked by addition of mannose-rich mannan. However, PRM shows little effect on virus growth and the expression of viral glycoproteins on the cell surface in hPIV2-infected HeLa cells. Fluorescein-isothiocyanate-labeled pradimicin and Con A bound to both uninfected and hPIV2-infected mononuclear cells, indicating that these compounds have an affinity to several cellular component(s). In contrast to Con A, PRM had little affinity to the viral glycoproteins. It is inferred from these results that the enhancement of hPIV2-induced cell fusion is probably due to the interaction between PRM and cellular component(s).  相似文献   
95.
We designed the present study to examine the cross-sectional relation between age-related lens opacities and vitamin C supplement use over a 10-12-y period before assessment of lens status in women without diagnosed cataract or diabetes. This design avoids biased measurement of nutrient intake that results when knowledge of lens opacities influences nutrition-related behavior or its reporting. The participants were 247 Boston-area women aged 56-71 y selected from the Nurses' Health Study cohort with oversampling of women with high or low vitamin C intakes. Lens opacities were graded with the Lens Opacification Classification System II. Use of vitamin C supplements for > or = 10 y (n = 26) was associated with a 77% lower prevalence of early lens opacities (odds ratio: 0.23; 95% CI: 0.09, 0.60) at any lens site and a 83% lower prevalence of moderate lens opacities (odds ratio: 0.17; 95% CI: 0.03, 0.85) at any lens site compared with women who did not use vitamin C supplements (n = 141) after adjustment for age and other potentially confounding variables. Women who consumed vitamin C supplements for < 10 y showed no evidence of a reduced prevalence of early opacities. These data, together with data from earlier experimental and epidemiologic studies, suggest that long-term consumption of vitamin C supplements may substantially reduce the development of age-related lens opacities.  相似文献   
96.
We retrospectively reviewed 11 patients with culture-proven Acanthamoeba keratitis who presented at the National Taiwan University Hospital between 1989 and 1996. We assessed predisposing factors, initial diagnosis, clinical presentation, treatment, and outcome. A history of contact lens-wear, poor contact lens hygiene, intractable eye pain, and ring infiltrates in the cornea were the most prominent characteristics and clinical manifestations. Acanthamoeba keratitis was often misdiagnosed, with herpetic keratitis (7/11) being the most common initial diagnosis from referring hospitals. These patients were usually treated on the basis of the inaccurate diagnosis for more than 1 month (range 1-8 mo) before referral. All patients ultimately received penetrating keratoplasty because of poor response to delayed medical treatment. We suggest that inadequate contact lens hygiene may be important in Acanthamoeba keratitis. This condition is often misdiagnosed and, as early diagnosis is a major factor for successful medical treatment in such patients, awareness in clinical practice is critical.  相似文献   
97.
A newly identified member of the fibroblast growth factor (FGF) family, designated FGF-10, is expressed during development and preferentially in adult lung. The predicted FGF-10 protein is most related to keratinocyte growth factor (KGF, or FGF-7). The latter is unique among FGFs in that it binds and signals only through the FGF receptor (FGFR2b) isoform KGF receptor (KGFR) expressed specifically by epithelial cells. In order to examine the biological and biochemical properties of human FGF-10, we isolated the cDNA and expressed its encoded protein in bacteria. The recombinant protein (rFGF-10) was a potent mitogen for Balb/MK mouse epidermal keratinocytes with activity detectable at 0.1 nM and maximal at around 5 nM. Within this concentration range, FGF-10 did not stimulate DNA synthesis in NIH/3T3 mouse fibroblasts. rFGF-10 bound the KGFR with high affinity comparable to that of KGF, and did not bind detectably to either the FGFR1c (Flg) or FGFR2c (Bek) receptor isoforms. The mitogenic activity of FGF-10 could be distinguished from that of KGF by its different sensitivity to heparin and lack of neutralization by a KGF monoclonal antibody. These results indicate that FGF-10 and KGF have similar receptor binding properties and target cell specificities, but are differentially regulated by components of the extracellular matrix.  相似文献   
98.
A 19-year-old woman was admitted to Kushiro city general hospital due to chest pain and dyspnea. Chest radiographs and computed tomographic scan showed a large intrathoracic mass adjacent to the pleura. Angiographs disclosed feeding veins of the tumor arising from lateral thoracic artery. Fine-needle aspiration cytology of the tumor revealed small round cells with a large nuclear/cytoplasmic ratio. Immunocytochemical study demonstrated that the tumor cells were positive for neuron-specific enolase and MIC 2 gene product. The diagnosis was primitive neuroectodermal tumor of the parietal pleura (also known as Askin tumor). Chemotherapy combined with peripheral blood stem cell transplantation reduced the size of the tumor significantly. However, multiple bone metastasis recurred, and the patient died 35 months after the start of therapy.  相似文献   
99.
A vacuolar H+-ATPase-negative mutant of Saccharomyces cerevisiae was highly sensitive to nickel ion. Accumulation of nickel ion in the cells of this mutant of less than 60% of the value for the parent strain arrested growth, suggesting a role for this ATPase in sequestering nickel ion into vacuoles. An artificially imposed pH gradient (interior acid) induced transient nickel ion uptake by vacuolar membrane vesicles, which was inhibited by collapse of the pH difference but not of the membrane potential. Nickel ion transport into vacuoles in a pH gradient-dependent manner is thus important for its detoxification in yeast.  相似文献   
100.
The rotating dilution refrigerator has been built up and tested to study topology and dynamics of vortices in thin helium films in porous glasses. The torsional oscillator method is considered as the basic technique to be used. We are able to rotate the cryostat with angular velocity up to 6.3 rad/s and resolve changes of about 0.3 mrad/s. The 40mK minimum temperature of the cryostat does not change up to the highest angular velocities.  相似文献   
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