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141.
142.
Over a two-month period in 1992, a team in the Radiology Department at Bloomington Hospital recorded the number and types of delays that occurred in the computer tomography (CT) scanning process. Using the Pareto principle, the team identified two root causes for delays--equipment failure and insufficient information collected at scheduling. Appropriate interventions were identified, and the number of delays decreased dramatically. Results: The number of delays in the CT scanning process decreased from a median of 19 per day to 2. Staff overtime hours decreased from a median of 87 per month to 46. The time patients spend waiting to receive a CT scan decreased from an average of 20 minutes to 30 minutes to 0 to 10 minutes. Patients are scheduled for a scan within one day's notice, as opposed to one week previously. Complaints from patients, physician offices, and other customers decreased dramatically. Morale and empowerment improved among staff. 相似文献
143.
A comparison was made of four methods for assessing tumour vascularity in carcinoma of the cervix. Formalin fixed tumour sections were stained with Masson's trichrome and measurements were made of the percentage of tumour blood vessels, vascular density (i.e. the proportion of blood vessels in the stroma) and inter-capillary distance (ICD). ICD was also obtained on anti-Factor VIII stained sections. The assessment of tumour vascularity was shown to be operator-dependent. For all the methods examined, statistically significant differences were seen between the values obtained by two people independently scoring the same sections. Nevertheless, weak correlations were seen between the different scorers for all the methods with measurements of ICD giving the strongest correlations. Either weak or no correlations were seen between the various methods used for assessing the tumour vasculature. An evaluation was made of the ability of the various methods to predict patient outcome for patients a minimum of two years post treatment with radiotherapy alone. Only measurements of the percentage of tumour blood vessels were shown to correlate with patient outcome. These data highlight the importance of having a single individual obtain measurements of tumour vascularity and suggest that the method chosen to determine vascularity may influence the results obtained. 相似文献
144.
Jan M. West Danielle C. Humphris D. George Stephenson 《Journal of muscle research and cell motility》1995,16(3):267-284
Summary Long-(SL>6m) and short-sarcomere (SL<4m) fibres were isolated from the claw muscle of the yabby (Cherax destructor) during limb regeneration and at different stages of the moult cycle. Long-sarcomere fibres were more susceptible to the changes resulting from the moult-induced atrophy compared with the short-sarcomere fibres. Signs of atrophy included fibre erosion, loss of myosin filaments, a reduction in the diameter of myosin filaments and changes associated with the Z line. The intracellular structure of the fibres, however, remained intact in both fibre types. Fibres taken immediately prior to ecdysis could not be fully activated with Ca2+ or Sr2+ without breaking. In contrast fibres taken within 4 h after ecdysis could develop and maintain full force when activated by Ca2+ or Sr2+. The results suggest that loss of myofibrillar proteins via the moult-induced atrophy and/or events associated with fibre elongation may occur in the period just prior to ecdysis and that these changes may be responsible for the fibres inability to function during the premoult stage. Results from this study showed that short-sarcomere fibres add sarcomeres by at least two different mechanisms (1) transverse sarcomere splitting and (2) Z line splitting. Long-sarcomere fibres appear to be elongated by mechanism (s) other than those used by short-sarcomere fibres which possibly involve large electron dense structures which are positioned between the myofibrils and within the A and I bands. Results from the regenerating chelae limb bud showed that sarcomeres form from separate units comprising myosin filaments and actin filaments anchored into Z lines respectively. These sub-sarcomeric units then join together to form sarcomeres. Myofibril formation is aided by electron dense regions which are closely associated with the membrane system. These fibres although short in length and still within the non-functional limb bud could be activated by Ca2+ and Sr2+ suggesting that full fibre function exists before the chelae become functional. Regenerating muscle fibres consisted predominately of fibres with short-sarcomeres. 相似文献
145.
Brain R. West Harry Applebaum Bradford W. Edgerton 《Pediatric surgery international》1994,9(4):301-303
The most common approach to the pepair of pectus excavatum and pectus carinatum deformities is via a central transverse submammary incision. The subsequent suprasternal scar is conspicuous and prone to hypertrophic and keloid scarring. To avoid the keloid triangle and to produce a less noticeable scar, we have utilized bilateral inframammary incisions for repairs of five female and two male patients with pectus defects. This approach provides excellent access for cartilage resection, sternotomy, and sternal tupport without increasing opearative time or compromising operative exposure. On follow-up for up to 25 months, all patients have had excellent cosmetic and functional results. Chest wall configuration and stability, wound healing, and scar formation have all been without complication. No keloid or hypertrophic scars have developed. To date, there has been no recurrence of pectus defects. We believe bilateral inframammary incisions are a superior approach for pectus repairs by enchancing cosmesis with less noticeable scars and fewer hypertropic and keloid scars, all without compromising operative exposure or increasing operative time. 相似文献
146.
Oxygen enrichment of room air to improve well-being and productivity at high altitude. 总被引:11,自引:0,他引:11
J B West 《International journal of occupational and environmental health》1999,5(3):187-193
Increasingly, commercial activities, such as mines, and scientific facilities, such as telescopes, are being placed at very high altitudes, up to 5,000 m. Frequently workers commute to these locations from much lower altitudes, or even from sea level. In addition, large numbers of people permanently live and work at high altitudes. The hypoxia of high altitude impairs sleep quality, mental performance, productivity, and general well-being. Recently it has become feasible to raise the oxygen concentration of room air by injecting oxygen into the air conditioning. This is remarkably effective at reducing the equivalent altitude. For example, increasing the oxygen concentration by 1% (e.g., from 21% to 22%) reduces the equivalent altitude by about 300 m. In other words, a room at an altitude of 4,500 m containing 26% oxygen is effectively at an altitude of 3,000 m. Oxygen enrichment has now been tested in several studies and shown to improve sleep quality and cognitive function. The fire hazard is less than in air at sea level. This innovative technique promises to improve productivity and well-being at high altitude. 相似文献
147.
John C. West 《Journal of healthcare risk management》1999,19(3):14-25
Sexual harassment can arise in virtually any employment setting. Healthcare facilities must be careful to avoid sexual harassment of their employees both fry other employees and by the myriad other persons who may come into contact with their employees in the workplace. Much of what makes sexual harassment an actionable offense are the perceptions of the victim. Employers should take a proactive approach to preventing, detecting and correcting instances of harassment. 相似文献
148.
G Ursin A H Wu R N Hoover D W West A M Nomura L N Kolonel M C Pike R G Ziegler 《American journal of epidemiology》1999,150(6):561-567
Breast cancer incidence has historically been 4-7 times higher in the United States than in Asia. A previous study by the authors in Asian-American women demonstrated a substantial increase in breast cancer risk in women who migrated from Asia to the United States, with the risk almost doubling during the first decade after migration. Increased use of oral contraceptives soon after migration to the United States could possibly explain this rapid rise in risk. In a population-based case-control study of Chinese, Filipino, and Japanese-American women, aged 20-55 years, who lived in San Francisco-Oakland, California; Los Angeles, California; and Oahu, Hawaii during 1983-1987, 597 cases (70% of those eligible) and 966 controls (75%) were interviewed. Controls were matched to cases on age, ethnicity, and area of residence. Oral contraceptive (OC) use increased with time since migration; 15.0% of Asian-born women who had been in the West <8 years, 33.4% of Asian-born women who had been in the West > or =8 years, and 49.6% of Asian women born in the West had ever used OCs. However, duration of OC use (adjusted for age, ethnicity, study area, years since migration, education, family history of breast cancer and age at first full-term birth) was not associated with increased risk of breast cancer. Moreover, neither OC use before age 25 years nor before first full-term birth was associated with increased risk. Results were unchanged when restricted to women under age 45 years or under age 40 years. After adjustment for duration of OC use, women who had been in the United States > or =8 years were still at almost twice the risk of breast cancer compared with women who had been in the United States 2-7 years. This study suggests that OC use cannot explain the elevated risk observed in Asian women who migrated to the United States > or =7 years ago. 相似文献
149.
Castenmiller JJ Lauridsen ST Dragsted LO van het Hof KH Linssen JP West CE 《The Journal of nutrition》1999,129(12):2162-2169
In vitamin A-replete populations, increased concentrations of serum carotenoids have been associated with a decreased risk of degenerative diseases. The mechanism of action of carotenoids in determining antioxidant activity is largely unknown. The aim of the study was to examine the effect of carotenoid supplementation and spinach intake on erythrocyte enzyme antioxidant activities, serum or plasma nonenzymatic antioxidant concentrations, and concentrations of oxidatively damaged amino acids in plasma. Subjects received for 3 wk a basic diet (n = 10), a basic diet with a carotenoid supplement (n = 12) or with a spinach product (n = 12 per group), i.e., whole-leaf, minced, liquefied or liquefied spinach plus added dietary fiber. After 3 wk of dietary intervention, changes in serum or plasma concentrations of ascorbic acid, alpha-tocopherol, FRAP (ferric reducing ability of plasma) and uric acid and erythrocyte enzyme activities were assessed, and differences among experimental groups were tested. Consumption of spinach resulted in greater (P < 0.01) erythrocyte glutathione reductase activity and lower (P < 0.05) erythrocyte catalase activity and serum alpha-tocopherol concentration compared with the control group. Consumption of the carotenoid supplement led to lower alpha-tocopherol responses (P = 0.02) compared with the basic diet only. Our data suggest that the short-term changes in erythrocyte glutathione reductase activity and serum alpha-tocopherol concentration can be attributed to an increased carotenoid (lutein and zeaxanthin) intake, but beta-carotene is unlikely to be a causative factor. Lower erythrocyte catalase activity after intervention with spinach products may be related to other constituents in spinach such as flavonoids. 相似文献
150.