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41.
42.
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
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Custer CM Custer TW Rosiu CJ Melancon MJ Bickham JW Matson CW 《Environmental toxicology and chemistry / SETAC》2005,24(1):93-109
Concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in tree swallows (Tachycineta bicolor) nesting along the Woonasquatucket River northwest of Providence (RI, USA) in 2000 and 2001 were some of the highest ever reported in avian tissues. Mean concentrations in eggs ranged from 300 to >1,000 pg/g wet weight at the two most contaminated ponds, Allendale and Lyman. Mean egg concentrations at Greystone, the upstream reference pond, were 12 and 29 pg/g. Positive accumulation rates and concentrations in diet samples from 12-day-old nestlings indicated that the contamination was accumulated locally. Concentrations in diet of between 71 and 219 pg/g wet weight were more than 6 and 18 times higher than concentrations considered safe for birds (10-12 pg/g). Hatching success was negatively associated with concentration of TCDD in eggs. Only about half the eggs hatched at Allendale compared with >77% at Greystone. The national average for hatching success in successful nests is 85%. No other contaminants, such as polychlorinated biphenyls and mercury, were present in any sample at concentrations known to affect avian reproduction. Three bioindicators, half-peak coefficient of geometric variation, ethoxyresorufin-O-dealkylase activity, and brain asymmetry were assessed relative to TCDD contamination. 相似文献
46.
S B Melancon M Vanasse G Geoffroy L Barabe A Proulx G Fontaine L Dallaire M Potier 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》1982,9(2):155-164
Twenty-two patients with Friedreich's Ataxia and ten normal controls were followed for one year and assessed as to their clinical performance after two successive six-month periods of lecithin or safflower oil. Results demonstrated no significant difference in performance scores according to group assignation, neither in patients nor in controls. According to stages, two patients in stage I and to a lesser degree, one patient in stage IV showed better scores for muscle strength and some motor accuracy and coordination tests with lecithin. Controls as groups maintained positive scores in all tests. Patients as groups showed negative mean values in nine out of eleven tests. Again as groups, patients receiving safflower oil demonstrated a mean 8% less deterioration than patients receiving lecithin. This study demonstrates that objective clinical tests and the participation of normal controls are a must in a therapeutic trial implicating patients with a progressive disorder such as Friedreich's Ataxia. The possible role of linoleic acid as the active factor from which clinical improvement proceeded in some specific patients and with early functional stages of the disease, has to be considered and reevaluated in the near future. 相似文献
47.
A diagnosis of ovarian cancer requires a woman to reevaluate her interactions with family, friends, and employers, and cope with unexpected and unwanted changes in areas spanning from financial stability to sexuality and fertility. Social well-being is the aspect of a patient's overall quality of life that encompasses these topics, as it has evolved to represent activities related to roles and relationships at work and at home. The purpose of this study was to explore the social well-being of women with ovarian cancer to better define their needs for the health care community. Data consisted of all correspondence (n = 21,806) sent to 'Conversations!: The newsletter for those fighting ovarian cancer' by women with ovarian cancer from 1994 to 2000. Using ethnographic, qualitative research methods, statements related to the impact of disease were bracketed and coded within physical, psychological, social, and spiritual domains according to the City of Hope Quality of Life Ovarian Cancer Instrument. Comments reflecting social well-being were categorized in sub-themes and reviewed for content. Statements related to social support were most common (n = 251) reflecting the need for support from family, friends, and other women with ovarian cancer. Distress regarding the genetic association of the disease comprised a major theme (n = 73). Family relationships were also discussed (n = 146) in light of the stress of changing roles and relationships at home. Issues related to employment and returning to work (n = 74) focused on both the difficulties in taking time off work to receive treat-ment and sense of achievement felt upon returning to work and regaining normalcy. The themes identified in this study challenge healthcare professionals to provide increased disease-specific support, as well as concomitant sup-port for husbands/partners and children of patients. Additional information on genetic testing and counseling for women at-risk due to a family history of ovarian cancer is also needed. 相似文献
48.
Mammary intraepithelial neoplasia outgrowths (MINO): MINO and human ductal carcinoma <Emphasis Type="Italic">in situ</Emphasis> 总被引:1,自引:0,他引:1
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Germ-line mutations in the BRCA1 tumour suppressor gene contribute to familial breast tumour formation, but there is no evidence for direct mutation of the BRCA1 gene in the sporadic form of the disease. In contrast, decreased expression of the BRCA1 gene has been shown to be common in sporadic tumours, and the magnitude of the decrease correlates with disease progression. BRCA1 expression is also tightly regulated during normal breast development. Determining how these developmental regulators of BRCA1 expression are co-opted during breast tumourigenesis could lead to a better understanding of sporadic breast cancer aetiology and the generation of novel therapeutic strategies aimed at preventing sporadic breast tumour progression. 相似文献
49.
Custer TW Custer CM Hines RK Stromborg KL Allen PD Melancon MJ Henshel DS 《Archives of environmental contamination and toxicology》2001,40(1):89-100
Double-crested cormorant (Phalacrocorax auritus) eggs at pipping and sibling 10-day-old chicks were collected from two colonies in Green Bay, WI, one colony in Lake Michigan,
WI, and reference colonies in South Dakota and Minnesota. Egg contents and chicks were analyzed for organochlorine contaminants
including polychlorinated biphenyl (PCB) congeners. Livers of embryos and chicks were assayed for hepatic microsomal ethoxyresorufin-O-dealkylase (EROD) activity. Eggshell thickness and the physical dimensions of embryo brains were measured. Concentrations
of organochlorines, including p,p′-DDE (p,p′-dichlorodiphenyldichloroethylene), PCBs, and PCB congeners were generally an
order of magnitude higher in eggs and chicks from Wisconsin than from reference locations. Total PCBs averaged 10–13 μg/g
wet weight in eggs from three Wisconsin colonies compared to 0.9 μg/g PCBs from reference locations. Double-crested cormorant
chicks accumulated on average 33–66 μg PCBs/day and 7–12 μg p,p′-DDE/day in the Wisconsin colonies compared to 0 μg PCBs/day
and 1 μg p,p′-DDE/day in the reference colonies. At pipping, EROD activity in the livers of cormorant embryos was significantly
higher in the Wisconsin colonies and significantly correlated with PCBs and the toxic equivalents (TEQs) of aryl hydrocarbon-active
PCB congeners relative to 2,3,7,8-tetrachlorodibenzo-p-dioxin. However, in 10-day-old chicks EROD activity was not consistently different among colonies and was not correlated
with PCBs or TEQs. A significant negative relationship between embryo brain asymmetry and the size of the egg suggested that
physical constraint might be an important factor influencing the response of this bioindicator. Thinner eggshells in two colonies
located near Door County, Wisconsin, suggested that historic p,p′-DDE residues associated with orchards are still an important
source of p,p′-DDE in the local environment.
Received: 26 April 2000/Accepted: 18 July 2000 相似文献
50.
Cefalu WT; Wagner JD; Bell-Farrow AD; Edwards IJ; Terry JG; Weindruch R; Kemnitz JW 《Toxicological sciences》1999,52(2):49-55
Caloric restriction (CR) has been observed to retard aging processes and
extend the maximum life span in rodents. In an effort to evaluate the
effect of this nutritional intervention on physiologic variables in higher
species, several nonhuman primate trials are ongoing. In particular, a
study evaluating the independent effect of CR on the extent of
atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys.
Therefore, the trial was designed to achieve identical cholesterol intake
after animals were randomized to a control group or a calorie-restricted
group (30% reduction from baseline caloric intake). The animals were
routinely evaluated for glycated proteins, plasma insulin and glucose
levels, insulin sensitivity, and specific measures for abdominal fat
distribution by CT scans over a 4-year interval. The results from 4 years
of intervention demonstrate that CR improves cardiovascular risk factors
(such as visceral fat accumulation) and improves insulin sensitivity. In
contrast to other primate studies with normolipidemic animals, CR had no
independent effects on plasma lipid levels and composition in the presence
of equivalent amounts of dietary cholesterol intake. Preliminary analysis
of atherosclerotic lesion extent in the abdominal aorta has failed to
demonstrate differences between control animals and CR animals. Follow- up
studies are being conducted to determine the effect of CR on
atherosclerosis extent in coronary and carotid arteries.
相似文献