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991.
Nyholt DR; Dawkins JL; Brimage PJ; Goadsby PJ; Nicholson GA; Griffiths LR 《Human molecular genetics》1998,7(3):459-463
Migraine is a common complex disorder that shows strong familial
aggregation. There is a general increased prevalence of migraine in females
compared with males, with recent studies indicating that migraine affects
18% of females compared with 6% of males. This preponderance of females
among migraine sufferers coupled with evidence of an increased risk of
migraine in first degree relatives of male probands but not in relatives of
female probands suggests the possibility of an X-linked dominant gene. We
report here the localization of a typical migraine susceptibility locus to
the X chromosome. Of three large multigenerational migraine pedigrees two
families showed significant excess allele sharing to Xq markers (P = 0.031
and P = 0.012). Overall analysis of data from all three pedigrees gave
significant evidence in support of linkage and heterogeneity (HLOD = 3.1).
These findings provide conclusive evidence that familial typical migraine
is a heterogeneous disorder. We suggest that the localization of a migraine
susceptibility locus to the X chromosome could in part explain the
increased risk of migraine in relatives of male probands and may be
involved in the increased female prevalence of this disorder.
相似文献
992.
External validation of prognostic models for ongoing pregnancy after in- vitro fertilization 总被引:3,自引:2,他引:3
Stolwijk AM; Straatman H; Zielhuis GA; Jansen CA; Braat DD; van Dop PA; Verbeek AL 《Human reproduction (Oxford, England)》1998,13(12):3542-3549
This study aimed to validate prognostic models for predicting ongoing
pregnancy after the first and second in-vitro fertilization cycles. Models
were developed using data from the University Hospital, Nijmegen, 1991-1994
and tested using more recent data from the same centre and data from two
other centres. Although the variables included in the models seemed
plausible, the predictions of the models were unsatisfactory. The models
did not discriminate between women who had achieved pregnancy and women who
did not achieve pregnancy; neither could they indicate which women had a
(very) low probability of ongoing pregnancy. Taking into account the
success rate of a specific clinic or the success rate during a specific
period did not show any advantage. The predictions were even inaccurate in
the same hospital during another period. It is obvious that these
prognostic models should not be used. This study shows the importance of
validating prognostic models before their implementation in clinical
practice.
相似文献
993.
Schiebel K; Winkelmann M; Mertz A; Xu X; Page DC; Weil D; Petit C; Rappold GA 《Human molecular genetics》1997,6(11):1985-1989
XX males and XY females have a sex reversal disorder which can be caused by
an abnormal interchange between the X and the Y chromosomes. We have
isolated and characterized a novel gene on the Y chromosome, PRKY. This
gene is highly homologous to a previously isolated gene from Xp22.3, PRKX,
and represents a member of the cAMP-dependent serine threonine protein
kinase gene family. Abnormal interchange can occur anywhere on Xp/Yp
proximal to SRY. We can show that abnormal interchange happens particularly
frequently between PRKX and PRKY. In a collection of 26 XX males and four
XY females, between 27 and 35% of the interchanges take place between PRK
homologues but at different sites within the gene. PRKY and PRKX are
located far from the pseudoautosomal region where XY exchange normally
takes place. The unprecedented high sequence identity and identical
orientation of PRKY to its homologous partner on the X chromosome, PRKX,
explains the high frequency of abnormal pairing and subsequent ectopic
recombination, leading to XX males and XY females and to the highest rate
of recombination outside the pseudoautosomal region.
相似文献
994.
Takasuke Yamachika J Lawrence Werther Carol Bodian Mark Babyatsky Masae Tatematsu Yoshitaka Yamamura Anli Chen Steven Itzkowitz 《Clinical cancer research》2002,8(5):1092-1099
PURPOSE: Intestinal trefoil factor (ITF) is a marker of intestinal differentiation that may also play a role in cancer cell biology by inhibiting cell adhesion, promoting cell invasion, and blocking apoptosis. Gastric adenocarcinomas can arise through a process of intestinalization, but no study has yet comprehensively examined the expression of ITF in gastric cancer or correlated ITF expression with clinical outcome in any cancer type. EXPERIMENTAL DESIGN: Patients (209) with primary gastric adenocarcinoma were evaluated for ITF expression by immunohistochemistry. Results of immunostaining were correlated with clinicopathological variables and overall survival. RESULTS: In normal gastric mucosa, ITF expression was absent, whereas areas of intestinal metaplasia revealed strong ITF expression by goblet cells. A portion of gastric cancers (55%) demonstrated ITF expression. Women were more likely than men to express ITF in gastric cancers. However, in men, the expression of ITF correlated with aggressive phenotype of tumors (advanced stage, infiltrative growth pattern, and positive lymph nodes). Multivariate analysis revealed that expression of ITF was associated with a poor prognosis, independent of tumor stage. CONCLUSIONS: This is the first study to correlate ITF expression with clinicopathological features or outcome in any cancer type. ITF expression in gastric cancer exhibited a curious gender-associated relationship, being more frequently expressed in tumors of women, but associated with more aggressive pathological features in men. The poor prognosis of patients with ITF-positive gastric cancers further implicates ITF in cancer cell biology. 相似文献
995.
MF van der Wal DC van den Boom H Pauw-Plomp GA de Jonge 《Archives of disease in childhood》1998,79(4):312-317
OBJECTIVES: To investigate the prevalence of infant crying and maternal soothing techniques in relation to ethnic origin and other sociodemographic variables. DESIGN: A questionnaire survey among mothers of 2-3 month old infants registered at six child health clinics in Amsterdam, the Netherlands. SUBJECTS: A questionnaire on sociodemographic characteristics and crying behaviour was completed for 1826 of 2180 (84%) infants invited with their parents to visit the child health clinics. A questionnaire on soothing techniques was also filled out at home for 1142 (63%) of these infants. RESULTS: Overall prevalences of "crying for three or more hours/24 hour day" "crying a lot", and "difficult to comfort" were 7.6%, 14.0%, and 10.3%, respectively. Problematic infant crying was reported by 20.3% of the mothers. Of these infants, only 14% met all three inclusion criteria. Problematic crying occurred less frequently among girls, second and later born children, Surinamese infants, and breast fed infants. Many mothers used soothing techniques that could affect their infant's health negatively. Shaking, slapping, and putting the baby to sleep in a prone position were more common among non-Dutch (especially Turkish) mothers than among Dutch mothers. Poorly educated mothers slapped their baby more often than highly educated mothers. CONCLUSIONS: Mothers' reports of infant crying and soothing varied sociodemographically. Much harm may be prevented by counselling parents (especially immigrants) on how and how not to respond to infant crying. Health education should start before the child's birth, because certain soothing techniques could be fatal, even when practised for the first time. 相似文献
996.
In vivo He-3 MR images of guinea pig lungs 总被引:4,自引:0,他引:4
997.
998.
目的观察32P-磷酸铬胶体注入兔类风湿关节炎模型膝关节腔后对外周血淋巴细胞染色体畸变率的影响。方法9只新西兰兔随机分成3组,A组3只为正常对照;B组3只为模型对照;C组3只诱导成模型1周后,右膝关节腔内各注射32P-胶体磷酸铬44.4MBq。3组均在C组核素注射后2个月时经耳缘静脉采血,其中C组另在核素注射前、注射后3d时采血。经培养后比较各组分裂中期淋巴细胞染色体畸变率的变化。结果A、B、C3组外周血淋巴细胞染色体观察均未见双着丝粒,无着丝粒断片率3组无明显差异(P>0.05)。C组各时间点外周血淋巴细胞染色体观察也未发现双着丝粒,无着丝粒断片率也无明显差异(P>0.05)。结论关节腔注射实验剂量的32P-磷酸铬胶体,兔外周血淋巴细胞畸变率的波动在正常范围内,说明放射性滑膜切除术是一种安全的治疗方法。 相似文献
999.
1000.
F Bonvicini E Manaresi G Gallinella GA Gentilomi M Musiani M Zerbini 《BJOG : an international journal of obstetrics and gynaecology》2009,116(6):813-817
Objective The purpose of our work was to examine the most reliable laboratory diagnosis of fetal parvovirus B19 infection in hydropic fetuses by evaluating the most appropriate clinical sample and laboratory test.
Design B19 DNA detection in fetal samples and serological signs of B19 infection in the respective mothers. Samples collected between January 2000 and July 2008.
Setting Microbiology, University of Bologna, Bologna, Italy.
Samples One hundred thirty-five fetal samples (58 fetal cord blood and 77 amniotic fluid samples) and 109 serum samples collected from 109 pregnant women.
Methods Validated and certified in situ hybridisation assay (ISH) and polymerase chain reaction–enzyme-linked immunosorbent assay (PCR-ELISA) were performed on fetal samples to detect B19 DNA. B19-specific antibodies were investigated in maternal serum samples by a commercial enzyme immunoassay.
Main outcome measures Parvovirus B19 DNA detection in fetal specimens was analysed in relation to maternal serological signs of infection.
Results Parvovirus B19 DNA was detected in 22.41% of fetal cord blood and 36.36% of amniotic fluid samples. A statistically significant difference was found between DNA detection by ISH (23.70%) and PCR-ELISA (14.81%) ( P = 0.004). Only 11.76% of fetuses with virological diagnosis of B19 infection were from women with serological signs of acute/recent B19 infection.
Conclusions Diagnosis of fetal parvovirus B19 infection cannot always rely on maternal serological investigations but rather on the virological analysis of fetal samples. Both fetal cord blood and amniotic fluid samples are suitable for diagnosis, but the detection of B19 DNA in the cells of amniotic fluid samples by ISH proved to be the most reliable diagnostic system. 相似文献
Design B19 DNA detection in fetal samples and serological signs of B19 infection in the respective mothers. Samples collected between January 2000 and July 2008.
Setting Microbiology, University of Bologna, Bologna, Italy.
Samples One hundred thirty-five fetal samples (58 fetal cord blood and 77 amniotic fluid samples) and 109 serum samples collected from 109 pregnant women.
Methods Validated and certified in situ hybridisation assay (ISH) and polymerase chain reaction–enzyme-linked immunosorbent assay (PCR-ELISA) were performed on fetal samples to detect B19 DNA. B19-specific antibodies were investigated in maternal serum samples by a commercial enzyme immunoassay.
Main outcome measures Parvovirus B19 DNA detection in fetal specimens was analysed in relation to maternal serological signs of infection.
Results Parvovirus B19 DNA was detected in 22.41% of fetal cord blood and 36.36% of amniotic fluid samples. A statistically significant difference was found between DNA detection by ISH (23.70%) and PCR-ELISA (14.81%) ( P = 0.004). Only 11.76% of fetuses with virological diagnosis of B19 infection were from women with serological signs of acute/recent B19 infection.
Conclusions Diagnosis of fetal parvovirus B19 infection cannot always rely on maternal serological investigations but rather on the virological analysis of fetal samples. Both fetal cord blood and amniotic fluid samples are suitable for diagnosis, but the detection of B19 DNA in the cells of amniotic fluid samples by ISH proved to be the most reliable diagnostic system. 相似文献