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991.
992.
PURPOSE: To evaluate retrospectively the optimum dosage of irradiation for Kimura's disease. METHODS AND MATERIALS: Twenty patients with Kimura's disease were treated with radiotherapy. The sex ratio was 19 males to 1 female. The mean ages at onset, initial treatment, and radiotherapy were 26.2, 29.5, and 32.2 years, respectively. Radiotherapy was mainly applied for residual or recurrent tumors. The eosinophil count increased by more than 10% in 18 of the 20 patients. In most instances, irradiation was given through a single field with dosages ranging from 20 to 44 Gy. RESULTS: At the completion of radiotherapy, a marked response in tumor size was noted in all cases. The minimum follow-up was 48 months. Local control was obtained in 23 of 31 lesions (74.1%). At dosages of < or =25 Gy, 26-30 Gy, and > 30 Gy, local control was obtained in 2 of 8 (25.0%), 9 of 10 (90.0%), and 12 of 13 sites (92.3%), respectively. CONCLUSIONS: Radiotherapy is an effective treatment for Kimura's disease. This strongly suggests that no surgical procedure other than a biopsy should be carried out. The radiation field should be limited to the lesion and swelling of the adjacent lymph nodes as much as possible, with a optimum dosage of 26-30 Gy regardless of tumor size.  相似文献   
993.
994.
Recombinant immunotoxins have been shown to cure human tumor xenografts in mice, but their biodistribution to both tumors and normal organs has not been reported. Anti-Tac(Fv)-PE38 is a single-chain recombinant immunotoxin composed of the variable heavy and light domains of the anti-Tac monoclonal antibody that reacts with the primate interleukin 2 (IL2) receptor alpha subunit (IL2R alpha or CD25) fused to a truncated form of Pseudomonas exotoxin (PE). 125I-labeled anti-Tac(Fv)-PE38 was given i.v. to immunodeficient mice each bearing two A431 tumors, one that expresses IL2R alpha (ATAC-4) and one that does not (A431, parental). A single i.v. dose of 4 microg/mouse caused complete regression of the IL2R alpha + tumor. At 6 h, over 6% of the injected dose/g was found in the ATAC-4 tumor, and 2% was in the A431 tumor. Uptake in the ATAC-4 tumor was higher than in any other tissue. Sections of tumor examined by autoradiography indicated that anti-Tac(Fv)-PE38 was distributed throughout the entire tumor, with some portions having higher uptake than others. By subtracting uptake in tumors without receptor (A431) from uptake in receptor-containing tumors (ATAC-4), we calculated that at least 400 molecules/cell specifically bound to IL2R alpha-positive tumor cells at 90 min and 750 molecules/cell bound at 360 min. This is similar to the 400-870 molecules/cell required for >99.9% killing of ATAC-4 cells growing as a monolayer. The results show that solid tumors in mice can be eradicated like cells in tissue culture, and that delivery of less than 1000 molecules/cell is sufficient to cause complete tumor regressions.  相似文献   
995.
The authors present an overview of current graduate medical education (GME) issues, particularly the financial challenges to teaching hospitals resulting from the Balanced Budget and Tax Payer Relief Acts of 1997 and other recent market-driven factors. They describe in detail the nature of Medicare GME payments before and after the 1997 legislation, with specific examples, and explain the negative financial impact of the legislation and aspects of the legislation that are designed to alleviate that impact. Other factors influencing GME program size and composition are also discussed, including oversupplies or shortages of physicians, the concern that teaching hospitals are using public funds to train international medical graduates, changing training requirements, etc. The authors also describe a recent consulting assignment during which they assisted a major teaching hospital to develop a GME strategy that was responsive to the organization's mission and patients and that took into account future GME financing challenges. Detailed explanations are given of how the consultants analyzed the hospital's GME programs and finances, developed and ranked key institution-specific program criteria (strategic, organizational and operational, and financial), and, in consultation with all key stakeholders, formulated a GME strategy specific to the institution's needs. The authors conclude by cautioning that each institution's GME strategy will be different, but that it is important for institutions to develop such strategies to better face future challenges.  相似文献   
996.
997.
BACKGROUND: To clarify which types of cancer result from AIDS, we compared the cancer experiences of people with AIDS with those of the general population by matching population-based cancer and AIDS registries in the USA and Puerto Rico. METHODS: We used a probabilistic matching algorithm to compare names, birth dates, and, where available, social-security numbers of 98,336 people with AIDS and 1,125,098 people with cancer aged less than 70 years. We defined AIDS-related cancers as those with both significantly raised incidence post-AIDS and increasing prevalence from 5 years pre-AIDS to 2 years post-AIDS. FINDINGS: Among people with AIDS, we found 7028 cases of Kaposi's sarcoma (KS), 1793 of non-Hodgkin lymphoma (NHL), and 712 other cases of histologically defined cancer. Incidence rates among people with AIDS were increased 310-fold for KS, 113-fold for NHL, and 1.9-fold (95% CI 1.5-2.3) for other cancers. Of 38 malignant disorders other than KS and NHL, only angiosarcoma (36.7-fold), Hodgkin's disease (7.6-fold), multiple myeloma (4.5-fold), brain cancer (3.5-fold), and seminoma (2.9-fold) were raised and increasing significantly (p<0.02) from the pre-AIDS to the post-AIDS period. INTERPRETATION: Interpretation is complicated by screening and shared risk factors, such as sexual behaviour and cigarette smoking. However, our data indicate that AIDS leads to a significantly increased risk of Hodgkin's disease, multiple myeloma, brain cancer, and seminoma. Immunological failure to control herpes or other viral infections may contribute to these malignant diseases.  相似文献   
998.
Nitric oxide (NO) is detectable in the exhaled gas of adults during spontaneous respiration and, according to current knowledge, mainly originates from the paranasal sinuses. We studied total NO excretion rates by chemiluminescence in preterm infants whose paranasal sinuses are known to be only partially pneumatized. NO excretion was 7.15 +/- 1.13 nl/min (mean +/- SD, range 6.33-9.36 nl/min) measured from spontaneously exhaled nasal gas (n = 6) and 0.3 +/- 0.05 nl/min (range 0.26-0.36 nl/min) measured from the lower airways in intubated individuals (n = 3). These values are considerably lower than those reported for older children and adults. Body weight-related amounts of NO excretion, however, seem comparable between infants and adults.  相似文献   
999.
OBJECTIVE: To test whether isoenergetic isoenergetically-dense doses of dietary 1-monoglyceride or triglyceride differentially influence appetite and meal-to-meal energy intake in man. DESIGN: Six men and six women were each studied twice in a 2 d protocol. On day 1 (maintenance day) they were fed a medium fat (MF) maintenance diet (MF: 40% fat, 47% carbohydrate and 13% protein by energy) calculated at 1.6 x resting metabolic rate (RMR). On day 2 (manipulation day) at 08.30 h subjects consumed a high-fat breakfast designed to contain 80-85% of RMR, composition 10% protein, 56% fat and 34% carbohydrate by energy, with 65% of energy for fat derived as either 1-monoglyceride or triglyceride. Food and energy intake were monitored at lunch (given at 12.30pm) and throughout the remainder of the day. During this time subjects had ad libitum access to isoenergetic, isoenergetically dense MF (40:47:13) foods (550kJ/100g), until 22.30pm). Subjective hunger and satiety were tracked hourly, during waking hours. RESULTS: There was no significant effect of fat type on food or energy intake at lunch or during the ad libitum period. There was no diet effect on subjective hunger (F(1,10)0.00; P= 0.975) in the inter-meal periods of morning or afternoon, nor during the whole day. Subjects found both diets to be similarly pleasant (F(1,61)0.84;P= 0.364). Men and women responded similarly, except that men ate more on all occasions than women. CONCLUSIONS: This study suggests that when a large dose of l-monoglyceride or triglyceride is incorporated into a breakfast meal, it behaves in a manner that is very similar to triglyceride in terms of the effects on hunger, appetite or feeding behaviour.  相似文献   
1000.
The authors used a directed-forgetting task to investigate whether psychiatrically impaired adult survivors of childhood sexual abuse exhibit an avoidant encoding style and impaired memory for trauma cues. The authors tested women with abuse histories, either with or without posttraumatic stress disorder (PTSD), and women with neither abuse histories nor PTSD. The women saw intermixed trauma words (e.g., molested), positive words (e.g., confident), and categorized neutral words (e.g., mailbox) on a computer screen and were instructed either to remember or to forget each word. Relative to the other groups, the PTSD group did not exhibit recall deficits for trauma-related to-be-remembered words, nor did they recall fewer trauma-related to-be-forgotten words than other words. Instead, they exhibited recall deficits for positive and neutral words they were supposed to remember. These data are inconsistent with the hypothesis that impaired survivors exhibit avoidant encoding and impaired memory for traumatic information.  相似文献   
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