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61.
A Finch K Metcalfe J Lui C Springate R Demsky S Armel B Rosen J Murphy L Elit P Sun and S Narod 《Clinical genetics》2009,75(3):220-224
It is often recommended that women who carry a mutation in the BRCA1 or BRCA2 gene have their ovaries and fallopian tubes removed to reduce their risk of gynecologic cancer. The aim of this study was to evaluate women's perception of their risk of breast and ovarian cancer before and after prophylactic salpingo-oophorectomy. We surveyed 127 women who carry a BRCA1 or BRCA2 mutation and who underwent prophylactic salpingo-oophorectomy at the University Health Network, Toronto. Subjects were asked to estimate their risks of breast and ovarian cancer before and after surgery. Their perceived risks of cancers were then compared with published risks, based on their mutation status. BRCA1 carriers estimated their risk of breast cancer risk to be, on average, 69% before surgery and 41% after surgery. They estimated their risk of ovarian cancer to be 55% before surgery and 11% after surgery. BRCA2 carriers estimated their risk of breast cancer to be 69% prior to surgery and 45% after surgery and their perceived risk of ovarian cancer to be 43% before surgery and 8% after surgery. Compared with published risk figures, the perceived risk of ovarian cancer before prophylactic salpingo-oophorectomy was overestimated by 47% of BRCA1 mutation carriers and by 61% of BRCA2 mutation carriers. Most women who have undergone genetic counseling and subsequently choose prophylactic salpingo-oophorectomy accurately perceive their risk of breast cancer. However, in this study, many women overestimated their risk of ovarian cancer, particularly women who carry a BRCA2 mutation. 相似文献
62.
A. Finch M. Wang A. Fine L. Atri S. Khalouei M. Pupavac B. Rosen A. Eisen C. Elser G. Charames K. Metcalfe M.C. Chang S.A. Narod J. Lerner‐Ellis 《Clinical genetics》2016,89(3):304-311
In 2001, genetic testing for BRCA1 and BRCA2 was introduced in Ontario, for women at high‐risk of breast or ovarian cancer. To date over 30,000 individuals have been tested throughout Ontario. Testing was offered to all Ontario residents who were eligible under any of 13 criteria. We report the results of tests conducted at Mount Sinai Hospital from 2007 to 2014. A total of 4726 individuals were tested, 764 (16.2%) were found to carry a pathogenic variant (mutation). Among 3684 women and men who underwent testing without a known familial BRCA mutation, 331 (9.0%) were found to carry a mutation. Among 1042 women and men tested for a known family mutation, 433 (41.6%) were positive. There were 603 female mutation carriers, of these, 303 were affected with breast or ovarian cancer (50%) and 16 with another cancer (2.3%). Of 284 unaffected female carriers, 242 (85%) were tested for a known family mutation and 42 (15%) were the first person in the family to be tested. By placing greater emphasis on recruiting unaffected female relatives of known mutation carriers for testing, greater than one‐half of newly identified carriers will be unaffected. 相似文献
63.
Harriet A. Druker Lidia Kasprzak Louis R. Bgin Serge Jothy Steven A. Narod William D. Foulkes 《American journal of medical genetics. Part A》1997,72(1):30-33
Benign thyroid disease is a risk factor for nonmedullary thyroid carcinoma [Houlston and Stratton: Q J Med 88:685–693, 1995]. We report on a family with 7 members with benign and/or malignant thyroid neoplasia; one affected female died of a paravertebral alveolar rhabdomyosarcoma at age 20. The occurrence of thyroid nodular hyperplasia, nonmedullary thyroid cancer, and rhabdomyosarcoma in the same family may be due to chance, common environmental factors, or, most likely, genetic predisposition. Am. J. Med. Genet. 72:30–33, 1997. © 1997 Wiley-Liss, Inc. 相似文献
64.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
65.
Hamel N Feng BJ Foretova L Stoppa-Lyonnet D Narod SA Imyanitov E Sinilnikova O Tihomirova L Lubinski J Gronwald J Gorski B Hansen Tv Nielsen FC Thomassen M Yannoukakos D Konstantopoulou I Zajac V Ciernikova S Couch FJ Greenwood CM Goldgar DE Foulkes WD 《European journal of human genetics : EJHG》2011,19(3):300-306
The BRCA1 mutation c.5266dupC was originally described as a founder mutation in the Ashkenazi Jewish (AJ) population. However, this mutation is also present at appreciable frequency in several European countries, which raises intriguing questions about the origins of the mutation. We genotyped 245 carrier families from 14 different population groups (Russian, Latvian, Ukrainian, Czech, Slovak, Polish, Danish, Dutch, French, German, Italian, Greek, Brazilian and AJ) for seven microsatellite markers and confirmed that all mutation carriers share a common haplotype from a single founder individual. Using a maximum likelihood method that allows for both recombination and mutational events of marker loci, we estimated that the mutation arose some 1800 years ago in either Scandinavia or what is now northern Russia and subsequently spread to the various populations we genotyped during the following centuries, including the AJ population. Age estimates and the molecular evolution profile of the most common linked haplotype in the carrier populations studied further suggest that c.5266dupC likely entered the AJ gene pool in Poland approximately 400-500 years ago. Our results illustrate that (1) BRCA1 c.5266dupC originated from a single common ancestor and was a common European mutation long before becoming an AJ founder mutation and (2) the mutation is likely present in many additional European countries where genetic screening of BRCA1 may not yet be common practice. 相似文献
66.
67.
P Karagianni SA Polyzos N Kartali I Zografou C Sambanis 《Advances in medical sciences》2013,58(1):38-43
PurposeComparative efficacy of exenatide versus insulin glargine primarily on glucemic control, and secondarily on body mass index (BMI), lipid profile and blood pressure, in type 2 diabetes mellitus (T2DM) patients suboptimally treated with metformin monotherapy.Material/MethodsForty-seven inadequately treated T2DM patients on metformin assigned to exenatide (n=18) or insulin glargine (n=29) for 26 weeks. Glycosylated hemoglobin (HbA1c), serum lipids, BMI, systolic and diastolic blood pressure, and adverse events, including episodes of hypoglycemia and gastrointestinal symptoms, were recorded.ResultsEither treatment had a similar favorable mean reduction in HbA1c. However, more patients in exenatide group achieved HbA1c ≤ 7% at the 26th week compared with insulin glargine group (p=0.036). Insulin glargine group had significantly more episodes of hypoglycemia compared with exenatide group (p=0.039). Gastrointestinal adverse events were non-significantly higher in the exenatide group. A significantly greater BMI reduction was observed in exenatide group, whereas BMI was not altered in insulin glargine group. Total and LDL cholesterol (p=0.012), and triglycerides (p=0.016) significantly decreased, whereas HDL cholesterol increased (p=0.021) in the exenatide group, whereas only total cholesterol decreased in insulin glargine group. Changes in systolic and diastolic blood pressure were insignificant in both groups.ConclusionsExenatide provided similar reduction in HbA1c, but fewer episodes of hypoglycemia, compared with insulin glargine. Exenatide had also a favorable effect on weight loss, although more gastrointestinal adverse events. Exenatide may provide a justified alternative in second line treatment of T2DM, but more trials are required to elucidate its long-term safety and cost-effectiveness. 相似文献
68.
MB Delatycki M Wolthuizen MA Aitken C Hickerton SA Metcalfe KJ Allen 《Clinical genetics》2013,84(3):286-289
Hereditary hemochromatosis (HH) is a common preventable disorder of iron overload that can result in liver cirrhosis and reduced lifespan. Most HH is due to homozygosity for the HFE p.C282Y substitution. We conducted a study of screening for p.C282Y in high schools where p.C282Y heterozygotes (CY) individuals were informed of their genotype by letter. We studied whether these individuals understood the implications of their genotype, whether this resulted in anxiety or reduced health perception and whether cascade testing was higher in families of CY than wild‐type homozygous (CC) individuals. We found 586 of 5757 (1 in 10) screened individuals were CY. One month after receiving their result, 83% correctly answered that they have one copy of p.C282Y. There was no adverse change in anxiety or health perception from prior to screening to 1 month after receiving results. Significantly more family members of CY individuals than CC individuals were informed about HH and had testing for HH. In conclusion, we found that informing CY individuals of their genotype does not increase anxiety and the implications are generally well understood. This leads to cascade testing in a minority of families. CY individuals should be informed of their genetic status when identified by population screening. 相似文献
69.
GK Resaland A Mamen SA Anderssen LB Andersen 《Acta paediatrica (Oslo, Norway : 1992)》2009,98(4):687-692
Aim: To describe cardiorespiratory fitness and body mass index (BMI) values in a representative population of 9-year-old Norwegian children in two rural communities and compare present values with previous findings.
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult. 相似文献
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult. 相似文献
70.
Peripheral nerve disorders may be classified into compressive or entrapment neuropathies and non‐compressive neuropathies. Muscle denervation recognized on MRI may be a useful sign in the diagnosis of peripheral nerve disorders. Acute or subacute denervation results in prolonged T2 relaxation time, producing increased signal in skeletal muscle on short tau inversion‐recovery and fat‐suppressed T2‐weighted images. Chronic denervation produces fatty atrophy of skeletal muscles, resulting in increased muscle signal on T1‐weighted images. This review will outline and illustrate the various ways that muscle denervation as seen on MRI may assist in the diagnosis and localization of peripheral nerve disorders. 相似文献