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32.
目的探讨新生儿肺炎期间及肺炎合并心衰时肺动脉压力、心腔内径及心功能变化规律。方法用彩色多谱勒超声TR压差法检测肺炎期间及肺炎合并心衰时肺动脉压力、心腔内径及心脏功能,同时做血气及心肌酶谱检查,并与正常新生儿比较,找出变化规律。结论新生儿肺炎期间肺动脉压力增高、肺动脉内径增宽、血气及心肌酶谱均有不同程度改变。肺炎合并心衰时左心室内径及右心室内径均有不同程度的增大。同时也证明肺炎合并心衰时是肺动脉压力增高及毒素等作用的结果。  相似文献   
33.

Background and Purpose

Spontaneous intracranial arterial dissections are characterized by the sudden disruption of the internal elastic lamina in the intracranial arteries. The purpose of our retrospective study was to investigate whether patients with nontraumatic intracranial arterial dissections had normal endothelial function.

Methods

The study included symptomatic patients with nontraumatic intracranial arterial dissections who underwent an endothelial function test. Controls were selected from headache patients matched for sex and age. Endothelial function was assessed using flow-mediated dilatation. We investigated patients’ ankle brachial index and pulse wave velocity to determine the degree of atherosclerosis. Patient characteristics, brachial flow-mediated dilatation, ankle brachial index, and pulse wave velocity were compared between the 2 groups.

Results

During the study period, there were 22 patients with nontraumatic intracranial arterial dissections matched with 22 controls. Clinical characteristics were compared between the groups. Although there were no significant differences in ankle brachial index or pulse wave velocity between the 2 groups, patients with intracranial arterial dissections had lower flow-mediated dilatation values than controls (median flow-mediated dilatation, 3.95% in dissection patients versus 7.3% in controls, P = .0035). Brachial flow-mediated dilatation was impaired in symptomatic patients with nontraumatic intracranial arterial dissections despite the normal ankle brachial index and pulse wave velocity.

Conclusions

Impaired brachial flow-mediated dilatation is a probable predictor of intracranial arterial dissections.  相似文献   
34.
The diameters of six different sized Lightspeed cutting heads were measured using a modified optical micrometer. Six specimens of instrument sizes 20, 22.5, 27.7, 30, 32.5 and 45 were examined. Except for one cutting head of size 30, all the recorded diameters were oversized compared to the expected diameter and the permitted tolerance (+0.005 mm). Perfectly machined instruments would increase by 12.5%, 9.09% and 8.3% from instrument sizes 20–22.5, 27.5–30 and 30–32.5, respectively. Under the conditions of this study, the corresponding increases were 7.1%, 6.75% and 8.54%. Instrument size 20 had the widest range and is the smallest instrument in the Lightspeed set. The largest differences between the recorded and expected means were registered for the size 45 group. An earlier study using a different measuring method reported that Lightspeed instruments were mostly undersized.  相似文献   
35.
Because the lizard cochlear duct is anatomically accessible as well as relatively simple in structure it is an excellent model in which to study auditory hair cells, nerve fibers, and innervational patterns. The objectives of this study were to determine the intra- and interspecific variations of auditory hair cell and nerve fiber numbers, nerve fiber/hair cell ratios, and nerve fiber sizes in a varied of lizard species and to relate these to auditory function and phylogeny. Hair cell numbers were determined by SEM and serial frontal sections of the papilla basilaris and nerve fiber numbers and diameters by use of a Zeiss TGZ3 particle counter. The coefficient of variation of hair cell numbers varied from 3.2 to 16.6 (171 specimens, 15 species) and of nerve fiber numbers from 1.2 to 14.4 (381 specimens, 35 species). There was no correlation between hair cell or nerve fiber number and age or sex. The nerve fiber number/hair cell number ratio was 3.5-11.1/1 in small papillae basilares of the iguanid-agamid-anguid type, 2.4-3.2/1 in the teiid type, and 0.6-1.5/1 in the larger specialized papillae of the scincid and gekkonid types. Nerve fibers varied in diameter from 0.8 to 6.0 microns (largest percentage were 2-4 microns) and were unimodally distributed. Larger nerve fibers usually supplied the unidirectionally oriented hair cells of the papilla basilaris. Variations in hair cell and nerve fiber numbers in other vertebrate classes and the functional and phylogenetic aspects of lizard papilla basilaris structure and innervation are discussed.  相似文献   
36.
37.
ObjectivesTo determine whether: 1) retinal vessel diameters in pregnant and non-pregnant women with type 1 diabetes (T1D) alter the relationship of pregnancy to severity of diabetic retinopathy (DR); and 2) retinal vessel diameters in early pregnancy alter the relationship of severity of DR in the mother to severe adverse outcome in the infant.MethodsTwo cohorts of women with T1D, one composed of pregnant women and the other of non-pregnant women of child-bearing age, were recruited in Wisconsin. Baseline examinations (including retinal photography and collection of diabetes-related characteristics) were conducted, with follow-up approximately one year later. Retinal images were graded according to the modified Airlie House classification protocol, and retinal vessel diameters were measured from digitized images. The latter were included in analyses as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE).ResultsIn multivariate models: 1) Pregnancy was significantly associated with both incidence (OR = 4.43, CI = 1.42–13.79) and progression (OR = 2.62, CI = 1.52–4.51) of DR. Neither CRAE nor CRVE were significant, but their addition modestly altered the associations of pregnancy to worsening DR; 2) Baseline retinopathy (OR = 1.28, CI = 1.05–1.57) was associated with severe adverse outcome in the infant. This association was unchanged by adjustment for retinal vessel diameters.ConclusionsPregnancy is associated with worsening DR in women with T1D. DR severity in early pregnancy is associated with severe adverse outcome in the infant. The retinal vessel diameters CRAE and CRVE were not associated with these outcomes but were modest confounders of the association of pregnancy to worsening DR.  相似文献   
38.

Aim of the study

Lindera strychnifolia (LS) is widely used in traditional Chinese medicine. In the present study, we investigated cytotoxicity and antibacterial activity of essential oils and various fractions of ethanol extract of LS to explore the active components of LS and their pharmacological effects.

Materials and methods

The in vitro cytotoxicities of essential oils and various solvent fractions of LS on three human cancer cell lines (A549, HeLa and Hep G2) and a non-cancerous cell line (HUVEC) were examined using a modified MTT assay. And by using agar disc diffusion and broth microdilution methods, the antibacterial activity of these samples was evaluated against 10 bacteria including 5 clinically isolated strains. The compositions of the essential oils from the leaves and roots of LS were also analyzed by GC and GC–MS.

Results

The leaf oil showed the strongest cytotoxicity on the cancer cell lines tested with the IC50 values ranged from 22 to 24 μg/ml after 24 h of treatment. The most sensitive microbial strain to all the samples was Staphylococcus aureus ATCC 25923.

Conclusions

Our results showed that the essential oils of LS exhibited greater cytotoxicity and antibacterial activity than the solvent fractions of ethanol extract of LS.  相似文献   
39.
本文对中国美利奴羊(新疆军垦型)超细品系羔羊初生至15月龄的体重、体尺、羊毛生长逐月测定,并与成年羊进行比较.羔羊断奶前生长发育较快达到成年羊的70%,12月龄达到成年的90%,15月龄与成年羊差别很小.羊毛品质好,突出特点是羊毛纤维直径小。  相似文献   
40.
BackgroundCombination therapy with an inhaled corticosteroid (ICS) and a long-acting β2-agonist (LABA) in a single inhaler is the mainstay of asthma management. We previously showed that switching from salmeterol/fluticasone combination (SFC) 50/250 μg bid to a fixed-dose formoterol/budesonide combination (FBC) 9/320 μg bid improved asthma control and pulmonary functions, but not fractional exhaled nitric oxide (FeNO), in patients with asthma not adequately controlled under the former treatment regimen.ObjectiveTo assess whether switching from SFC to FBC improves peripheral airway/alveolar inflammation in asthma (UMIN000009619).MethodsSubjects included 66 patients with mild to moderate asthma receiving SFC 50/250 μg bid for more than 8 weeks. Patients were randomized into FBC 9/320 μg bid or continued the same dose of SFC for 12 weeks. Asthma Control Questionnaire, 5-item version (ACQ5) score, peak expiratory flow, spirometry, FeNO, alveolar NO concentration (CANO), and maximal NO flux in the conductive airways (J’awNO) were measured.ResultsSixty-one patients completed the study. The proportion of patients with an improvement in ACQ5 was significantly higher in the FBC group than in the SFC group (51.6% vs 16.7%, respectively, p = 0.003). A significant decrease in CANO was observed in the FBC group (from 8.8 ± 9.2 ppb to 4.0 ± 2.6 ppb; p = 0.007) compared to the SFC group (from 7.4 ± 7.8 ppb to 6.4 ± 5.0 ppb; p = 0.266) although there was no significant difference in the changes in pulmonary functions between the 2 groups. Similar significant differences were found in the CANO corrected for the axial back diffusion of NO (FBC, from 6.5 ± 8.2 ppb to 2.3 ± 2.5 ppb; and SFC, from 4.3 ± 5.3 ppb to 3.9 ± 4.3 ppb). There was no difference in the changes in FeNO or J’awNO between the 2 groups.ConclusionsSwitching therapy from SFC to FBC improves asthma control and peripheral airway/alveolar inflammation even though there is no improvement in pulmonary functions, and FeNO in asthmatic patients.  相似文献   
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