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451.
Mice lacking inducible nitric oxide synthase (iNOS) or treated with iNOS inhibitors resolved chlamydial genital tract infections. Additionally, treatment of primary murine cell cultures with gamma interferon restricted chlamydial growth in the absence of nitric oxide. From these results, iNOS activity is unnecessary for the resolution of chlamydial genital tract infections in mice and inhibition of chlamydial growth in culture.  相似文献   
452.
Intraperitoneal glucose tolerance tests were performed at 4-week intervals in groups of weanling rats before and after feeding with maize- or cassava-based diets with and without adequate protein and sublethal cyanide supplementation. Weaning weights were doubled (increase of about 50 g) after 4 weeks on control (maize-based with adequate protein) and protein-replete diets. Weight gain on the protein-deficient diets was much less (22 g or 50%), a pattern maintained by the rats on these diets until the age of 12 weeks. Plasma thiocyanate levels were identical at weaning and after 8 weeks of the control diet but increased by 200-300% after 4 weeks intake of the cassava or cyanide-supplemented feeds. Levels returned to normal in all groups after a further 4 weeks feeding with the control diet. Glucose tolerance (as assessed by the area under the 2 h glucose v. time curve) was impaired to a varying extent in the rats after 4 weeks on the various diets: protein-replete cassava and protein-deficient maize diets by 50% protein-deficient cassava diet by 300%, and cyanide-supplemented protein-deficient maize diet by 150%. The derangement in the rats on the protein-replete cassava diet was unaffected by a further 4 weeks intake of the control diet, unlike in the other groups where there was significant improvement in the glucose tolerance indices at the same time. It is concluded that in growing rats: (1) cassava intake and protein malnutrition may have independent and additive effects on the genesis of glucose intolerance, (2) cyanide supplementation of a cassava-free protein-replete diet has no effect on glucose tolerance.  相似文献   
453.
BACKGROUND: Benzopyrones can reduce the volume of high-protein edema fluid by stimulating proteolysis. These compounds provide a method for removing excess protein and its consequent edema and reduce its clinical sequelae, such as chronic inflammation and secondary infections. METHODS: We conducted a randomized, double-blind, placebo-controlled, crossover trial of 5,6-benzo-[alpha]-pyrone in 31 patients with postmastectomy lymphedema of the arm and 21 patients with lymphedema of the leg of various causes (this agent, also known as 56 BaP, 1,2-benzopyrone, or coumarin, is not an anticoagulant). The patients received 400 mg of the active drug or placebo, each for six months. RESULTS: During the placebo period, lymphedema often worsened, especially in the arms. Measurements of limb volume showed that the active drug reduced the mean amount of edema fluid in the arms from 46 percent above normal to 26 percent above normal (P < 0.001) and the amount in the legs from 25 percent to 17 percent above normal (P < 0.001). The circumference of the arms was reduced from 17 percent to 13 percent above normal, and the circumference of the legs from 11 percent to 7 percent above normal (P < 0.001). The softness of the limb tissue was increased (P < 0.001), and elevated skin temperatures were reduced (P < 0.001). There were fewer attacks of secondary acute inflammation (P = 0.01). Bursting pains and feelings of hardness were decreased, as were feelings of tightness, tension, swelling, and heaviness; limb mobility also improved. The active drug was preferred to the placebo by 93 percent of the patients (P < 0.001). Side effects--mild nausea or diarrhea--occurred in seven patients taking the active drug. None withdrew from the trial, and the side effects disappeared after the first month of therapy. CONCLUSIONS: 5,6-Benzo-[alpha]-pyrone results in slow but safe reduction of lymphedema of the extremities.  相似文献   
454.
OBJECTIVE: The purpose of this study was to determine the distribution of referred pain from the lumbar zygapophyseal joints (L1/2 to L5/S1) and the medial branches of the lumbar dorsal rami (Th12 to L5) in a large number of patients with chronic low back pain. SETTING: This study was conducted at the pain clinics of Kanto Teishin Hospital and Hannan Central Hospital from March 1994 to May 1996. PATIENTS AND DESIGN: Chronic low back pain patients who underwent zygapophyseal joint injection or radiofrequency facet denervation were studied. Under fluoroscopic control, the joints from L1/2 to L5/S1 were stimulated by injection of contrast medium, and the lumbar medial branches of the dorsal rami from Th12 to L5 underwent electrical stimulation during radiofrequency facet denervation. OUTCOME MEASURES: If the injection or electrical stimulation reproduced the patient's usual pain, the distribution of induced pain was determined, and the sites of induced pain were divided into six areas. RESULTS AND CONCLUSIONS: A total of 71 joints and 91 medial branches were studied in 48 patients. The distribution of referred pain from the L1/2 to L5/S1 zygapophyseal joints, and the medial branches of the dorsal rami from L1 to L5 were similar for each level stimulated, and the overlap of referred pain between each level was considerable.  相似文献   
455.
Hickman catheters were the major venous access devices utilized at the University of Maryland Cancer Center from November 1978 to 1987. This study provided an opportunity to standardize insertion technique, to manage catheter-related activities and daily maintenance procedures in order to examine the progression of Hickman-catheter-related problems, to identify those factors that may minimize them, and to develop guidelines for the management and prevention of complications and malfunctions. In all, 690 Hickman catheters (368 double lumens) were placed in patients with acute leukemia and other cancers: 401 catheters were placed in patients with leukemia; 269 were placed during neutropenia; and 230 at platelet counts of < 50,000/microliters. Two surgeons inserted 490 catheters, and the remaining 200 were placed by a group of rotating surgeons. All catheters were placed with the intention that they would remain in place as long as clinically necessary. Total Hickman catheter days were 134273. Infectious complications included exit site infections (160), tunnel infections (46) and bacteremias (397). There were 438 instances of noninfectious complications including thrombosis, lack of function, catheter migration, fracture and hemorrhage. Recommendations for prevention and treatment of Hickman-catheter-related complications include the development of a select group committed to placement, daily maintenance and management of problems; prompt removal of catheters with Candida sp. fungemia and bacteremia due to Bacillus sp. or a bacteremia that persists for > 48 h after initiation of appropriate antibiotics, tunnel infections or Hickman-catheter-associated thrombosis. The majority of bacteremias and exit site infections can be effectively treated with antibiotics and local care.  相似文献   
456.
OBJECTIVE: To determine the effect of a unique educational program in critical care medicine on the attitudes, knowledge, and skills of general internists who care for critically ill patients. DESIGN: Comparison of objective assessments and self-assessments obtained before and after the one-year educational program. SETTING/PARTICIPANTS: Eighteen general internists practicing in a 350-bed university-affiliated community teaching hospital. RESULTS: After the program, the internists felt significantly more competent in, knowledgeable about, comfortable with, and satisfied with caring for critically ill patients than they did when completing the precourse self-assessments (p < 0.05). Participants felt particularly more comfortable with managing ventilator patients and leading the advanced cardiac life-support team (p < 0.05). Comfort levels for other commonly performed critical care procedures did not vary. No significant change in knowledge test scores was noted from before to after the one-year program (61% vs 60%). Residents and nurses rated the internists' overall ability in critical care medicine to be the same as that of senior medical residents. They also favorably rated the internists on humanism, teaching skills, and interpersonal interactions. Residents also appreciated the decrease in their night call because of the program. CONCLUSIONS: This unique educational program increased comfort and satisfaction of general internists caring for critically ill patients. The program was well accepted by residents and nurses because of favorable interaction with the internists and a decrease in resident night-call responsibility. This curriculum is recommended to other teaching hospitals.  相似文献   
457.
Current advances have shown the apolipoprotein E (APOE)-epsilon 4 allele to be highly associated with late-onset familial and sporadic Alzheimer's disease (AD) in Western populations. The association of APOE allele frequencies and dementia remain unknown in populations from developing countries. We recently initiated a project to examine APOE frequencies in non-demented and demented elderly East Africans. Blood DNA collected from two hospital-based populations showed that the APOE allele frequencies in a group of non-demented 67 Tanzanians over the age of 65 years were found to be 14% for epsilon 2, 61% for epsilon 3 and 25% for epsilon 4. By comparison, the frequency of APOE-epsilon 4 in an age-matched demented group was also 25%. Assessment of APOE genotypes in the group of elderly Kenyan subjects from Nairobi also revealed high frequencies of the epsilon 4 allele with no clear difference in frequency between demented and non-demented subjects. Our preliminary observations suggest that elderly East Africans with no apparent clinical AD possess relatively high APOE-epsilon 4 allele frequencies compared to normal ageing subjects from Western countries including African-Americans. These results appear similar to those reported in a recent study in Nigerian Africans where a lack of correlation between APOE-epsilon 4 allele frequency and Alzheimer type of dementia was noted, and imply that APOE-epsilon 4 allele may not necessarily be a risk factor in some populations of Africa.  相似文献   
458.
Cytogenetic studies over the past 35 years have made a major contribution towards the understanding of the nature of Hodgkin's disease by demonstrating unequivocally the consistent presence of a clonal population of cells that have the cardinal features of malignancy e.g. more or less gross aneuploidy, frequently with complex chromosomal changes and showing considerable variation from case to case, thus comparable to the findings in carcinomas and other solid cancers. The mode is frequently in the triploid-tetraploid region, as we found in 17 of 27 cases studied in this laboratory by Feulgen microspectrophotometry, compared to only 10 cases with neardiploid modes. It is disappointing that no specific change, such as a translocation that could give a clue to the chromosomal location of a gene or genes involved in the etiology of Hodgkin's disease, has yet been found. Nevertheless it is clear that a number of nonrandom changes, including several that are also common in other malignancies including the non-Hodgkin's lymphomas, are frequently present, e.g., deletions of 1p, 6q, and 7q. Interestingly, deletions of 4q, with loss of 4q25 --> q27, that have also been reported may show some specificity for Hodgkin's disease.  相似文献   
459.
The experience of treatment of 15 children with isolated invagination of processus appendicularis was summarized. The clinic, diagnosis, principles of operative treatment were analyzed.  相似文献   
460.
Phosphorylation and dephosphorylation of the retinoblastoma gene product (pRB) are recognized as necessary events in the cell cycle progression. To study the role of pRB in regulation of cell proliferation, the stable cell lines with constitutive expression of the exogenous RB gene can be employed. In order to obtain such cell lines in this work C3H10T1/2 mouse fibroblasts were infected with defective retrovirus encompassing the RB and Neo gene conferring resistance to geniticine (G418). The pRB production and its phosphorylation pattern were analyzed by immunoblotting in cell lysates considering well known data on correlation between pRB phosphorylation pattern and its electrophoretic mobility. Cell lines subjected to G418 selection with the following cloning procedure were identical to the control cells expressing beta-galactosidase, when compared for pRB production and phosphorylation in the cell cycle stages characterized by hyperphosphorylated pRB. However, cells of the experimental cell lines hypophosphorylated pRB much faster and accumulated much more underphosphorylated protein compared to the control cell lines. The doubling time of the cells was not affected either by changes in the pRB phosphorylation pattern or by its overproduction during separate cell cycle stages. These results suggest that maintaining of the physiological level of pRB phosphorylation in cycling cells is strictly controlled and is considered to be a more important condition of the cell cycle progression than pRB dephosphorylation.  相似文献   
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