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991.
992.
993.
Characterization of survival motor neuron (SMNT) gene deletions in asymptomatic carriers of spinal muscular atrophy 总被引:14,自引:1,他引:13
Wang CH; Xu J; Carter TA; Ross BM; Dominski MK; Bellcross CA; Penchaszadeh GK; Munsat TL; Gilliam TC 《Human molecular genetics》1996,5(3):359-365
Previous reports have established that the telomeric copy of the survival
motor neuron (SMNT) gene and the intact copy of the neuronal apoptosis
inhibitory protein (NAIP) gene are preferentially deleted in patients with
spinal muscular atrophy (SMA). Although deletions or mutations in the SMNT
gene are most highly correlated with SMA, it is not clear to what extent
NAIP or other genes influence the SMA phenotype, or whether a small
fraction of SMA patients actually have functional copies of both SMNT and
NAIP. To evaluate further the part of SMNT in the development of SMA, we
analyzed 280 asymptomatic SMA family members for the presence or absence of
SMNT exons 7 and 8. We report the following observations: (i) 4% of the
sample harbored a polymorphic variant of SMNT exon 7 that looks like a
homozygous deletion; (ii) approximately 1% of the parents are homozygously
deleted for both exons 7 and 8; (iii) one asymptomatic parent lacking both
copies of SMNT exons 7 and 8 displays a 'subclinical phenotype'
characterized by mild neurogenic pathology; (iv) another asymptomatic
parent lacking both SMNT exons showed no signs of motor neuron disorder by
clinical and neurodiagnostic analyses. The demonstration of polymorphic
variants of exon 7 that masquerade as homozygous nulls, and the
identification of SMA parents who harbor two disease alleles, serve as a
caution to those conducting prenatal tests with these markers.
相似文献
994.
995.
JJ Goedert† BM Scoppio‡ R Pfeiffer† L Neve§ AB Federici‡ LR Long§ BM Dolan† M Brambati‡ M Bellinvia‡ C Lauria¶ L Preiss V Boneschi‡ D Whitby†† L Brambilla‡ 《Journal of the European Academy of Dermatology and Venereology》2008,22(9):1101-1109
Background Kaposi sarcoma (KS), a malignancy of dermal endothelial cells that is caused by human herpesvirus 8 (HHV8) infection, is sensitive to perturbations of immunity. Nicotine might be effective against KS because of its immunologic and vascular effects and because smoking is associated with a low risk of KS.
Objective and study design We conducted a masked, randomized phase 2 clinical trial of transdermal nicotine and placebo patches to assess the safety and efficacy of nicotine against classic KS (cKS).
Subjects and methods Three cKS lesions, predominantly nodules, in each of 24 non-smoking patients were randomly assigned to 15 weeks continuous treatment with nicotine patch (escalated to 7 mg), identical masked placebo patch or no patch. Changes in lesion area and elevation from baseline through six follow-up visits, by direct measurement and by two independent readers using digital photographs of the lesions, were compared using non-parametric and regression methods. Changes in longitudinal levels of HHV8 antibodies and DNA in blood cells were similarly assessed.
Results There were no systemic or serious adverse events, and compliance was good. One patient resumed smoking and discontinued patches, and two patients withdrew at week 12 for unrelated indications. Six (29%) of the remaining 21 suspended use of patches to relieve local skin irritation; four of these six completed the trial at reduced dose. Treatment assignment was not associated with significant or consistent changes in cKS lesion area or elevation, HHV8 viral load or antibodies.
Conclusion Transdermal nicotine and placebo patches caused no serious toxicities but had no demonstrable effect on nodular cKS lesions or HHV8 levels. 相似文献
Objective and study design We conducted a masked, randomized phase 2 clinical trial of transdermal nicotine and placebo patches to assess the safety and efficacy of nicotine against classic KS (cKS).
Subjects and methods Three cKS lesions, predominantly nodules, in each of 24 non-smoking patients were randomly assigned to 15 weeks continuous treatment with nicotine patch (escalated to 7 mg), identical masked placebo patch or no patch. Changes in lesion area and elevation from baseline through six follow-up visits, by direct measurement and by two independent readers using digital photographs of the lesions, were compared using non-parametric and regression methods. Changes in longitudinal levels of HHV8 antibodies and DNA in blood cells were similarly assessed.
Results There were no systemic or serious adverse events, and compliance was good. One patient resumed smoking and discontinued patches, and two patients withdrew at week 12 for unrelated indications. Six (29%) of the remaining 21 suspended use of patches to relieve local skin irritation; four of these six completed the trial at reduced dose. Treatment assignment was not associated with significant or consistent changes in cKS lesion area or elevation, HHV8 viral load or antibodies.
Conclusion Transdermal nicotine and placebo patches caused no serious toxicities but had no demonstrable effect on nodular cKS lesions or HHV8 levels. 相似文献
996.
997.
Human urethral glands were reacted histochemically and immunohistochemically to identify glycoproteins, some androgen metabolic enzymes, and VIP-like immunoreactivity. Neutral/acid mucosubstances were detected mainly in the apical cytoplasm of the principal cells. 3 beta-, 17 beta-, and 3 alpha-hydroxysteroid dehydrogenase, G6PD, and 6PGD reactivity were intense in all the glandular epithelium. Small amounts of VIP-positive fibers were noted around the secretory elements. 相似文献
998.
BM Junghans PhD SG Crewther PhD DP Crewther PhD B Pirie 《Clinical & experimental ophthalmology》1997,25(4):103-105
Purpose: Although it is generally thought that lymphatics do not exist in the choroid, there is mounting evidence that lymphatic-like structures do exist in primates and fowl. Methods/Results: Our comparison of the ultrastructure of chick and rabbit outer choroid indicates that major differences exist in the non-vascular areas of the choroid: notably, the chick has large lymphatic sinusoids, whereas the rabbit only has a system of large vacuoles contained within the processes of individual fibroblasts. Conclusions: These results raise questions regarding the similarities or otherwise between species of the management of retinal metabolites, excess tissue fluid and choroidal homeostasis, especially during conditions of overload. 相似文献
999.
J Greig MB ChB MRCP BM Groden FRCP FRCP 《International journal of clinical practice》1995,49(4):218-219
SUMMARY Flecainide acetate is a potent class 1C antiarrhythmic agent, overdosage with which is rare. An overdose is reported in a patient on long-term therapy, resulting in life-threatening arrhythmias and prolonged electrocardiographic abnormalities. 相似文献
1000.
Ewa Idvall RNT Liselotte Rooke RNT PhD Elisabeth Hamrin RN BM DMSc 《Journal of advanced nursing》1997,25(1):6-17
The purpose of the present study was, by means of a literature review, to describe and analyse the characteristics of clinical indicators used to assess and promote quality improvement in nursing care.
It was found that a generally accepted definition of a clinical indicator is a 'quantitative measure that can be used as a guide to monitor and evaluate the quality of important patient care and support service activities'. By the seriousness of the event and the degree to which it can be avoided, clinical indicators are described as sentinel event or rate-based indicators. They can measure structure, process or outcome of care. Authors have had different approaches in focus when selecting and developing indicators viz. specific aspects of care/nursing diagnosis, medical diagnosis, generic aspects of care and clinical areas. These different points of departure were influenced by research knowledge, theories/frameworks, or by the opinions of patients or staff.
The threshold of an indicator is essential when measuring the quality of care as it describes a critical level between what is considered good or not.
Thresholds should be dynamic, realistic, and improve over time. However, the literature on how to establish specific thresholds is limited.
The review has also revealed that there is an uncertainty regarding the use of terms such as indicators, standards, norm, criteria and aspects of care. 相似文献
It was found that a generally accepted definition of a clinical indicator is a 'quantitative measure that can be used as a guide to monitor and evaluate the quality of important patient care and support service activities'. By the seriousness of the event and the degree to which it can be avoided, clinical indicators are described as sentinel event or rate-based indicators. They can measure structure, process or outcome of care. Authors have had different approaches in focus when selecting and developing indicators viz. specific aspects of care/nursing diagnosis, medical diagnosis, generic aspects of care and clinical areas. These different points of departure were influenced by research knowledge, theories/frameworks, or by the opinions of patients or staff.
The threshold of an indicator is essential when measuring the quality of care as it describes a critical level between what is considered good or not.
Thresholds should be dynamic, realistic, and improve over time. However, the literature on how to establish specific thresholds is limited.
The review has also revealed that there is an uncertainty regarding the use of terms such as indicators, standards, norm, criteria and aspects of care. 相似文献