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Parotidectomy may be associated with a significant depression in the retromandibular region and a significant incidence of gustatory sweating (Frey's syndrome). Superiorly and inferiorly based sternocleidomastoid flaps and posterior plication of the superficial musculoaponeurotic system were evaluated for their ability to ameliorate both consequences. Sixteen patients with sternocleidomastoid flaps and 16 patients with superficial musculoaponeurotic system plication were compared to a control group of 104 patients. The incidence of Frey's syndrome was 47.1% in the control group, 12.5% (P = 0.025) in the sternocleidomastoid flap group, and 0% (P = 0.005) in the superficial musculoaponeurotic system plication group. The surgical techniques are described. The prevalence of Frey's syndrome is discussed with respect to age, sex, radiation therapy, and the type of parotidectomy performed. The indications and contraindications of the three surgical techniques are described.  相似文献   
3.
This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553  相似文献   
4.
Cells of Escherichia coli deleted for genes that code for the transducers and all the known cytoplasmic Che proteins except CheY responded reversibly to the addition of acetate by spinning their flagellar motors clockwise. By varying growth conditions and using metabolic inhibitors and mutants deficient in acetate metabolism, this effect was shown to require acetate-CoA synthetase [acetate:CoA ligase (AMP-forming); EC 6.2.1.1], an enzyme that catalyzes the formation of acetyl-CoA from acetate by an acetyladenylate intermediate. A mutant deficient in this enzyme but retaining the chemotaxis genes was deficient for chemotaxis. Thus, acetyladenylate appears to play a role in generating clockwise rotation at the level of CheY or the motor.  相似文献   
5.
C L Conley 《JAMA》1990,263(18):2481-2483
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6.
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: (1) frozen foods; (2) fresh produce and/or highly perishable foods requiring refrigeration; (3) fast foods and prepared foods; (4) shelf-stable foods; (5) specialized study and non-retail (point of production) foods; and (6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects.  相似文献   
7.
As a result of the expanded use of health-related quality of life (HRQL) measures in clinical trial research, a variety of legal and ethical issues have surfaced. These issues can be put in the form of the following questlons: (1) Under what circumstances should access to HRQL measures be restricted? (2) Under what circumstances is it appropriate for the developers of HRQL measures to assert their intellectual property rights to the instruments? (3) Under what circumstances is personal profit from the sale and use of HRQL measures legally and socially appropriate? Access to HRQL research is to be encouraged since this is necessary for this field to progress. However, the need for protection against misuse of ongoing work is real and may justify the assertion of intellectual property rights. HRQL measures developed entirely with public monles should remain in the public domain or be managed for the public good. Instruments developed with private funds or with a mix of public and private funds should be treated in a manner that refiects a fair balance between the rights of the private developer and those of the scientific community and the public. HRQL questionnaires are regularly being refined; such work is costly. Investigators continuing research directly related to instrument refinement might reasonably ask for compensation from those who wish to use their work.  相似文献   
8.
Recent studies have shown that mutations in a newly described RNA editing enzyme, activation-induced cytidine deaminase (AID), can cause an autosomal recessive form of hyper IgM syndrome. To determine the relative frequency of mutations in AID, we evaluated a group of 27 patients with hyper IgM syndrome who did not have defects in CD40 ligand and 23 patients with common variable immunodeficiency. Three different mutations in AID were identified in 18 patients with hyper IgM syndrome, including 14 French Canadians, 2 Lumbee Indians, and a brother and sister from Okinawa. No mutations were found in the remaining 32 patients. In the group of patients with hyper IgM syndrome, the patients with mutations in AID were older at the age of diagnosis, were more likely to have positive isohemagglutinins, and were less likely to have anemia, neutropenia, or thrombocytopenia. Lymphoid hyperplasia was seen in patients with hyper IgM syndrome and normal AID as well as the patients with hyper IgM syndrome and defects in AID.  相似文献   
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The relationship of toxoplasma antigen(s) to the origin and long-term persistence of the mononuclear cell inflammatory infiltrate that is present in the brains of mice chronically infected with Toxoplasma gondii was studied by using the peroxidase-antiperoxidase immunohistochemical staining technique. C3H/Km mice were infected with the avirulent C37 strain of T. gondii and sequentially sacrificed over the ensuing 107 days. Comparable sections of each brain were prepared for routine light microscopy. Antisera to toxoplasma made in rabbits were used for immunohistological staining, and adjacent slides were also stained with conventional histological stains. The peroxidase-antiperoxidase stain demonstrated toxoplasma tissue cysts, tachyzoites, and intra- and extracellular antigen-antibody reaction products. Early infection was characterized by small tight clusters of free tachyzoites gaining access to brain substance in the absence of an inflammatory response. Once there was disruption of neural parenchyma, a mononuclear cellular infiltrate rapidly ensued. After the first days of infection, mononuclear cells were always present in all infected brains and were anatomically associated with some component of toxoplasma antigen(s). The histological picture of late infection suggested that recurrent episodes of hematogenous dissemination of tachyzoites occurred in infected mice and that such episodes were at least partially responsible for persistence of an antigenic stimulus.  相似文献   
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