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681.
OBJECTIVES: To determine the usefulness of electrocardiography (ECG) and chest radiography (CXR) in evaluation of patients referred to the pediatric cardiologist for the evaluation of heart murmur or chest pain. DESIGN: In this prospective study, 106 consecutive outpatients were categorized with no heart disease, possible heart disease, or definite heart disease based on history and physical examination; they then underwent ECG and CXR. Studies were reviewed and the examining cardiologist could change the diagnosis and order an echocardiogram. SETTING: Academic pediatric cardiology practice. RESULTS: In patients thought to have no heart disease, the diagnosis was changed to definite heart disease in four solely on the basis of abnormal CXR or ECG. In 25 patients thought to have possible heart disease, the diagnosis was changed to no heart disease (7) or definite heart disease (5) after review of the CXR and ECG. All 25 patients diagnosed with definite heart disease had this confirmed by abnormal CXR (2), ECG (3), both abnormal CXR and ECG, or echocardiogram (18). CONCLUSIONS: ECG and CXR helped diagnose heart disease in four patients thought to have no heart disease, helped to rule out lesions in seven patients with possible heart disease, helped diagnose heart disease in five patients thought to have possible heart disease, and helped confirm heart disease in nine patients. In these days of cost containment, routine ECG and CXR continue to be valuable tools for the pediatric cardiologist in evaluation of patients with heart murmurs or chest pain. 相似文献
682.
BT Bloom J Kattwinkel RT Hall PM Delmore EA Egan JR Trout MH Malloy DR Brown IR Holzman CH Coghill WA Carlo AK Pramanik MA McCaffree PL Toubas S Laudert LL Gratny KB Weatherstone JH Seguin LD Willett GR Gutcher DH Mueller WH Topper 《Pediatrics》1997,100(1):31-38
OBJECTIVE: To compare the relative safety and efficacy of Infasurf (calf lung surfactant extract; ONY, Inc, Amherst, NY, IND #27169) versus Survanta (Beractant, Ross Laboratories, Columbus, OH) in reducing the acute severity of respiratory distress syndrome (RDS) when given at birth and to infants with established RDS. DESIGN: A prospective, randomized, double-blind, multicenter clinical trial. SETTING: Thirteen neonatal intensive care units participated in the treatment arm: seven of these concurrently participated in the prevention arm. PATIENTS: The treatment arm enrolled infants of =2000 g birth weight with established RDS, and the prevention arm enrolled infants of =29 weeks' gestation with birth weights <1250 g. INTERVENTION: Infants were randomly assigned to receive Infasurf (n = 303, treatment arm; n = 180, prevention arm) or Survanta (n = 305, treatment arm; n = 194, prevention arm) in accordance with the Survanta package insert instructions. OUTCOME MEASURES: We projected a 25% reduction between groups in the need for a third dose of surfactant for infants with established RDS, and a 25% reduction in the need for a second dose of surfactant for infants who received prophylactic surfactant. Secondary outcomes included the severity of RDS measured by inspired oxygen concentrations and mean airway pressure, air leaks, complications associated with surfactant administration, and survival to 36 weeks' postmenstrual age without the need for oxygen supplementation. RESULTS: In the treatment arm, there was no difference between groups in the number of infants requiring more than two doses of surfactant. The interval between doses was significantly longer for Infasurf, suggesting an increased duration of treatment effect. The inspired oxygen concentration and mean airway pressure were lower in the Infasurf infants during the first 48 hours in the treatment arm. In the prevention arm, there were no differences with respect to the number of surfactant doses. The dosing intervals were longer for Infasurf infants after the second dose. No difference in inspired oxygen or mean airway pressure was noted during the first 72 hours. There were no significant differences in the incidence of air leaks, complications associated with dosing, complications of prematurity, mortality, or survival without chronic lung disease in the prevention or treatment arm. CONCLUSIONS: Infants treated with Infasurf have a modest benefit in the acute phase of RDS. Infasurf seems to produce a longer duration of effect than Survanta. 相似文献
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685.
The supplementation of culture medium with protease improves the hatching rate of mouse embryos 总被引:1,自引:1,他引:1
Lee DR; Lee JE; Yoon HS; Lee HJ; Kim MK; Roh SI 《Human reproduction (Oxford, England)》1997,12(11):2493-2498
Mammalian embryos are known to exhibit delayed development and have lower
hatching rates in vitro than in vivo because of inadequate culture
condition. These discrepancies may be due to a deficiency of the paracrine
factors and proteolytic enzymes which exist in the oviduct and uterus. In
order to evaluate the effects of proteases on embryonic development and
hatching, 2-cell mouse embryos were cultured for 72 h with or without
proteases. The addition of 1.0 microg/ml pronase (PE) and/or 0.1 microg/ml
proteinase K (PK) did not affect embryonic development up to the blastocyst
stage (94.1% versus 88.2%; 92.2% versus 90.2%, respectively) but
significantly increased the hatching rate (60.4% versus 39.2%, 71.8% versus
35.3%, respectively). However, the addition of alpha-chymotrypsin (Chymo)
was detrimental to embryonic development and hatching. Changes in the
structure of the zona pellucida (ZP) structure of embryos which had been
cultured in human tubal fluid (HTF) medium with PE and PK were assessed by
fluorescein isothiocyanate-conjugated (FITC)-casein. Embryos cultured in
HTF-PE and PK were not stained with FITC-casein. When these embryos were
cultured within oviducts, their perivitelline space (PVS) became strongly
stained with FITC-casein which was easily removed by phosphate- buffered
saline washing. This suggests that PE and PK altered the structure of the
ZP. We suggest that the addition of PE and PK to culture media may
accelerate the hatching of embryo, by structurally altering the ZP and PVS.
This may provide a valuable and effective assisted hatching technique for
human in-vitro fertilization-embryo transfer.
相似文献
686.
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
687.
Electro-encephalogram disturbances in different sleep-wake states following exposure to high environmental heat 总被引:5,自引:0,他引:5
Sinha RK 《Medical & biological engineering & computing》2004,42(3):282-287
In this study, cerebral electrical activity or electro-encephalogram (EEG) was studied following exposure to high environmental
heat, in three different age groups of freely moving rats. Each age group was subdivided into three groups: the acute heat
stress group, subjected to a single exposure of 4h at 38°C in the biological oxygen demand incubator; the chronic heat stress
group, exposed for 21 days, for 1 h each day, at 38°C in the incubator; and the handling control group. The polygraphic sleep-wake
recordings involved simultaneous recordings of cortical EEG, electrooculogram (EOG), and electromyogram (EMG), on paper and
in digital form on computer hard disk, just after the heat exposure for the acute stressed rats and on the 22nd day for the
chronic stressed rats. The power spectrum was calculated for 2s epochs of the EEG signals. Quantitative analyses of EEG (qEEG)
showed that, in all three age groups, changes in higher-frequency components (β2) were significant in all sleep-wake states following both acute and chronic heat stress conditions. The power of β2 activity in all three age groups after acute heat exposure was significantly decreased during slow wave sleep (SWS) (p<0.05)
and rapid eye movement sleep (p<0.05), whereas the reverse was observed in the awake state (p<0.05). Following chronic heat
exposure, β2 activity was found to increase in all three sleep-wake stages in all groups of rats (p<0.01 for SWS in the weaning group
and p<0.05 for other data). Thus the study demonstrated that the cortical EEG is sensitive to environmental heat, and alterations
in EEG frequencies in different states of mental consciousness due to high heat can be differentiated efficiently by EEG power
spectrum analysis. 相似文献
688.
Do sequence variants in the major non-coding region of the mitochondrial genome influence mitochondrial mutations associated with disease? 总被引:12,自引:1,他引:12
Several different mutations in human mitochondrial DNA (mtDNA) have been
associated with disease, but their origins and the basis of the wide
phenotypic variability remain to be elucidated. We initially investigated
three patients with heteroplasmic disease associated mutations of mtDNA for
the presence of cis mutations in the major non- coding region that might
influence their origins or pathology. A T --> C transition at nt 16 189
previously identified in one patient with the 3243 G:C mutation was
associated with heteroplasmic length variation. Identical length variation
was found in patient-derived cybrid lines containing 0-97.5% 3243 G:C.
Similarly, heteroplasmic length variation was demonstrated in 2/6 other
probands with both the 3243 mutation and the 16,189 polymorphism. The
distribution of length variants in probands and in asymptomatic family
members was identical in all cases. Thus length variation appears to be
independent of the level of 3243 mutant mtDNA and hence probably arose
within both 3243 G:C and 3243 A:T mtDNAs. We suggest that the 16,189
polymorphism reflects a predisposition to the formation or fixation of
several different mutations in mitochondrial tRNA-LeuUUR.
相似文献
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