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81.
We describe an efficient method for embedding frozen-section specimens. Transparent tape is used to produce a well on the surface of the tissue holder ("chuck"). This well contains a quantity of nonmotile mounting media in which a tissue specimen can be easily oriented. After freezing, the tape is removed, leaving a relatively smooth surface. 相似文献
82.
Recall strategies and memory for health-care visits 总被引:2,自引:0,他引:2
J B Jobe A A White C L Kelley D J Mingay M J Sanchez E F Loftus 《The Milbank quarterly》1990,68(2):171-189
Complex questions in health surveys place heavy cognitive demands on respondents, prompting researchers to appraise how specific cognitive interventions may improve the accuracy of people's answers. Investigators in one experiment asked participants to recall visits to medical providers in forward, backward, or no particular order, and matched results with providers' records. "Free" recall proved marginally superior to forward or backward ordering, although overall respondents underreported the number of visits by 20 percent; participants' gender and self-reported health status, among other factors, also affected quality of recall. The experiment lends support to contentions that the methods of cognitive science applied to survey research better the accuracy of population survey data. 相似文献
83.
Handler A Rosenberg D Johnson T Raube K Kelley MA 《Maternal and child health journal》1997,1(3):173-177
Objectives: This study describes the use of a Medicaid managed care list to prospectively recruit into a research project pregnant women receiving care from a variety of providers. Method: A list of women enrolled in Medicaid managed care was used to recruit pregnant African-American and Latina women into a study of prenatal care satisfaction. Due to privacy concerns, the researchers were not able to directly access names from the list. Instead, a managed care contract agency sent recruitment letters to 1009 pregnant African-American and Latina Medicaid recipients. Response rates by ethnicity and several other key variables are calculated. The biases associated with this method of recruiting pregnant women from a variety of providers are discussed. Results: Thirty-five percent of the women contacted returned consent forms and agreed to have researchers approach them; the response rate for African-American women was 43% and for Latinas was 29% (p < 0.0001). Respondents were younger and later in their pregnancies than nonrespondents, but did not differ from them by zip code of residence. The women recruited into the study obtained prenatal care from a diverse group of providers. Conclusions: While the use of a prospectively generated list of pregnant Medicaid recipients to recruit low-income pregnant women into a research study may be associated with some selection bias, the potential cost savings, decreased effort, and diminished recall bias may make their use a feasible sampling alternative, particularly when the researcher desires to recruit women seeking care from a variety of provider arrangements. 相似文献
84.
85.
86.
Both sexes of C57BL/6 (C57) mice consumed substantial quantities of ethanol without food or water deprivation whether access was continuous or limited. Food deprivation increased the amount of ethanol consumed, and the amount consumed depended upon when the animals were tested with reference to their daily food allotment. Ethanol consumption was greater if the mice were tested postprandially, high thirst motivation, rather than preprandially (approximately 10 vs. approximately 4.5 g/kg/30 min). Preference for ethanol over water, however, was greater when mice were under low thirst motivation (i.e., tested preprandially or with water available during the test). Compared to males, female mice consumed more of a high-ethanol concentration solution (10%) when access was continuous or limited to the first hour of the dark (active) phase of the circadian cycle. Also, in contrast to males, female mice exhibited increased ethanol consumption across days of drinking experience. Finally, although ethanol consumption under the food deprivation conditions of this experiment did not differ according to sex, females had higher blood ethanol concentrations than male C57 mice, a finding not previously reported for rodents but common to humans. 相似文献
87.
Asthma has a significant impact on U.S. military expenditures and readiness. Every year approximately 1,000 recruits are discharged for asthma during their first 6 months of service. This study was done to evaluate the practice of allowing some individuals with a history of asthma to enter military service (waiving). A survival analysis was performed to compare length of time until discharge and asthma-related failure for individuals waived for asthma (cases) and individuals not disqualified for asthma (controls). Cases were 587 recruit applicants initially disqualified who received waivers for asthma and accessed in the years 1995 to 1997. Controls were 1,761 matched enlisted recruits starting basic training in those years. No significant differences were found with respect to general attrition. The statistical differences for asthma-related hospitalization or discharge did not translate into practical differences. Waiving for asthma was not a significant occupational liability in terms of asthma-related hospitalization or early military attrition. 相似文献
88.
89.
Proliferative lesions of oviduct and uterus in CD-1 mice exposed prenatally to tamoxifen 总被引:1,自引:3,他引:1
Tamoxifen (TAM) is widely used as adjuvant breast cancer therapy after
surgery and as a chemopreventive agent in women of child-bearing age.
However, TAM therapy has been shown to result in an increased incidence of
endometrial carcinoma in women. The present study was designed to
investigate the effects of TAM (5 mg/kg and 7.5 mg/kg body wt) given i.g.
to pregnant CD-1 mice (1x/day, days 12 through 18 of gestation) on their
female offspring. Progressive proliferative hyperplasia of the oviduct was
frequently seen in TAM-exposed offspring, reaching 100% incidence by 52
weeks in both treatment groups. These females also developed progressive
proliferative uterine lesions, including moderate/severe cystic endometrial
hyperplasia (34-50%) and polypoid adenomas (27-30%) between 53 and 78
weeks. Deciduomas (15%) occurred at young ages (12 and 24 weeks) while
leiomyomas (14%), a malignant leiomyosarcoma, and ovarian granulosa cell
tumors (14%), were found between 72 and 78 weeks. Our findings thus suggest
a strong association between transplacental TAM and reproductive tract
abnormalities in female CD-1 mice.
相似文献
90.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献