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71.
72.
An instrument to assess the dynamic characteristics of the circumvaginal musculature 总被引:1,自引:0,他引:1
This report describes an intravaginal balloon device (IVBD) and an improved method for measuring the dynamic characteristics of circumvaginal muscle (CVM) contractions. The IVBD measurement system may be used in research on women's health problems related to the pelvic floor musculature. The system is independent of examiner judgment and variability, and measurement conditions are carefully controlled. In an initial trial using the device with 20 volunteers, aged 22 to 58 years, the maximal pressure developed during strong CVM contractions was measured with the subjects supine. Subjects were asked to repeat the contraction while they contracted abdominal muscles. The length of time a submaximal contraction could be held was also measured. Test-retest reliability, determined by repeating each experiment, revealed significant correlations in maximal pressure attained, r = .85, p less than .03. A t test demonstrated no significant difference between the variables with and without the use of abdominal muscles, indicating the contraction of abdominal muscles did not affect intravaginal pressure when assessed with the IVBD. A weak correlation between length of time a submaximal contraction could be held and age of subject was found, r = -.44, p less than .06, but no pressure variable was correlated with age or parity, a possible effect of the small sample in this study. 相似文献
73.
B J Hurlbut J F Lubar R Switzer J Dougherty M L Eisenstadt 《Physiology & behavior》1987,39(3):381-393
Ten adult male Sprague-Dawley rats were infused with hemicholinium (HC-3) using mini-osmotic pumps over a 14 day period through bilateral, chronically implanted cannulae in the nucleus basalis magnocellularis (nbm). Ten matched controls were infused in the same fashion with saline. HC-3 rats receiving implants demonstrated a significant deficit in maze-learning ability compared with individual and group performances before receiving the implants. In saline rats there was no significant difference in maze-learning ability before and after receiving implants. The HC-3 group receiving implants demonstrated a significant deficit in maze-learning ability compared with the saline control group. Serial sections through nbm from control and HC-3 rats indicated that all cannulae were located within infusion range of nbm. In HC-3 subjects, cholinergic cell bodies were destroyed with concurrent degeneration of terminal fields in cortex. Except for cannula insertion damage, the cholinergic neurotransmitter system appeared unharmed in controls. Stains for neuritic plaques and neurofibrillary damage were negative in both groups. The memory deficit in experimental subjects supported by the demonstrated destruction of nbm cholinergic neurons suggests that HC-3 may be useful in the development of an animal model for Alzheimer's Disease. 相似文献
74.
Glenn Stuart Simon John L. Egle Jr. Robert W. Dougherty Joseph F. Borzelleca 《Toxicology letters》1986,30(3):237-245
Male rats received 3.6 or 11.4 mg/kg/day of chlordecone orally for 5 days. Some statistically significant events were seen in the reproductive data of females mated to males receiving chlordecone. However, these events did not follow a consistent pattern and do not suggest the conclusion that chlordecone causes dominant lethal effects. Male rats received a single oral dose (40 mg/kg) of chlordecone and were killed at 1, 2, 3, 5, 7, 14 or 21 days. Chlordecone was distributed throughout the reproductive tract. The descending order of concentration was seminal vesicular fluid > prostate > vas deferens > seminal vesicle > unwashed sperm > washed sperm. It is concluded that chlordecone is well distributed throughout the reproductive tract of the male rat, appears in the ejaculate, and does not appear to produce dominant lethal effects. 相似文献
75.
The most common cause of death in fires is the inhalation of noxious gases rather than thermal injury. Hydrogen cyanide gas, the most toxic product of combustion, seldom is recognized as a significant hazard in smoke inhalation. During the first four months of 1986, toxic amounts of cyanide were found in four of the six fatalities from house fires in Akron, Ohio. These cases illustrate the increasing frequency of cyanide poisoning in household fires. Sources of cyanide toxicity include the increased use of synthetic polymers in building materials and furnishings. Prompt recognition of and therapy for cyanide intoxication may reduce the morbidity and number of delayed deaths in fire victims. The key point in the diagnosis of cyanide poisoning is a high index of suspicion. The clinical presentation of cyanide intoxication, its diagnosis, and subsequent treatment are discussed. Finally, a prehospital protocol for treating smoke-inhalation victims who may have been exposed to cyanide gas is suggested. 相似文献
76.
R J Bonney P Davies H Dougherty R W Egan P H Gale M Chang M Hammond N Jensen J MacDonald K Thompson 《Biochemical pharmacology》1987,36(22):3885-3891
The biochemical and biological profile of a topical anti-inflammatory agent, 2,3-dihydro-6-[3-(2-hydroxymethyl)phenyl-2-propenyl]-5-benzofuranol (L-651,896 inhibited the 5-lipoxygenase of rat basophilic leukemia cells with an IC50 of 0.1 microM and leukotriene synthesis by human PMN and mouse macrophages with IC50 values of 0.4 and 0.1 microM respectively. L-651,896 also inhibited prostaglandin E2 synthesis by mouse peritoneal macrophages (IC50 = 1.1 microM). This compound inhibited ram seminal vesicle cyclooxygenase activity at considerably higher concentrations, and this effect was directly related to substrate concentration. When applied topically to the mouse ear, L-651,896 lowered elevated levels of leukotrienes associated with arachidonic acid-induced skin inflammation and delayed hypersensitivity induced by oxazolone. However, while L-651,896 inhibited the increased vascular permeability induced by arachidonic acid, it had no effect on the edema associated with the immune-based response to oxazolone in the same tissue. Thus, it is possible that leukotrienes may play a role in some but not all inflammatory responses. 相似文献
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Inward buckling of the dura at C1-2 may occasionally occur with hyperextension of the neck and can result in a difficult or unsuccessful puncture when the posterior lateral C1-2 approach is used for cervical myelography. In this circumstance, placement of the head in a neutral or slightly flexed position may widen the posterior subarachnoid space and facilitate the needle puncture. 相似文献
80.
Preoperative chemotherapy for children with Wilms' tumor. 总被引:6,自引:0,他引:6
M Greenberg C Burnweit R Filler S Weitzman H Sohl H Chan D Jenkin M Dougherty M Berry A Balcolm 《Journal of pediatric surgery》1991,26(8):949-53; discussion 953-6
Five years ago, the use of preoperative chemotherapy for Wilms' tumor was adopted at this institution. Thirty children ranging in age from 5 months to 9 years had histologically confirmed Wilms' tumor (needle biopsy, n = 26; open biopsy, n = 4). Stage was determined by chest and abdominal computed tomography (CT) scan. Bilateral tumors were present in 6 children. All children received actinomycin D and vincristine from 3 weeks to 6 months before surgery. Seven children with bilateral tumors or stage IV disease also received adriamycin. CT-measured tumor masses shrunk in most cases. Subsequently, nephrectomy was performed in 23 patients and partial nephrectomy in 4, 2 of whom had bilateral disease. In 2 patients, residual bilateral well-differentiated epithelial tumor was not surgically resected. One child died before surgery. Reevaluation at delayed total or partial nephrectomy resulted in a downstaging of disease in 12 (41%). Further chemotherapy and radiation was based on the surgical stage. Postoperative chemotherapy (4 months to 2 years) was administered to all patients. The chest and/or abdomen were radiated in 12. Four patients (13%) died, 1 of radiation pneumonitis and 3 of the disease progression (2 with unfavorable histology, 1 of whom had bilateral disease). Two of 4 with unfavorable histology and 4 of 6 with stage IV disease have survived. It is concluded that this preoperative chemotherapy protocol is as effective as the National Wilms' Tumor Study (NWTS) protocol. The treated tumor is smaller, less friable, and easier to remove. Furthermore, because of downstaging, less radiation is necessary for cure. 相似文献