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51.
52.
To determine whether cesarean delivery is associated with a better outcome than vaginal delivery for infants weighing less than 1500 g (very low birth weight), we examined neonatal mortality and the incidence of intraventricular hemorrhage (IVH) in 1765 very low birth weight inborn infants admitted to seven neonatal intensive care centers. The cesarean rate was 32.5% for infants weighing 501-750 g and 52.4% for infants weighing 751-1000 g. The neonatal death rate was 53.1% for infants weighing 501-750 g delivered by cesarean, compared with 64.3% for vaginally born infants (P = .046). However, for infants weighing 1001-1250 g, the neonatal death rate for infants delivered by cesarean was 14.4%, compared with 7.8% for infants born vaginally (P = .02). The incidence of IVH was significantly lower in infants born by cesarean than in those born vaginally only in the 1251-1500-g birth weight interval (11.8 versus 18.9%; P = .03). Compared with women delivering vaginally, those delivered by cesarean were more likely to attain a higher mean gestation, to have preeclampsia, and to have a breech presentation, and less likely to be in labor. After adjusting by logistic regression for gestational age, preeclampsia, breech presentation, presence or absence of labor, and for center effects, the odds ratio for neonatal death was 1.00 (95% confidence interval 0.71-1.41); for IVH, the odds ratio was 0.85 (95% confidence interval 0.61-1.19). These data suggest that after accounting for certain maternal and fetal factors, cesarean delivery is not associated with a lower risk of either mortality or IVH. 相似文献
53.
Data from a nationally representative sample of household interviews were analyzed to examine public preparedness for childhood poisoning episodes. Eighty-eight percent (61% to 77% in nonwhite groups) of respondents from households with children younger than 10 years had heard of poison control centers and 70% (50% to 57% in nonwhites) stated that they had the telephone number of such a center. In contrast only 25% stated they had syrup of ipecac in their home. Among blacks and Hispanics this proportion was 9%. To explore possible reasons for this we telephoned a sample of 65 physicians listed in the greater Washington, DC, telephone directory as providers of care for infants and children. Of the 45 (69%) who agreed to be interviewed, 73% informed their patients about poison control centers and 53% provided the appropriate telephone number. Although 78% believed parents should have ipecac in the house, only three (7%) of 45 actually dispensed ipecac to parents. We conclude that ipecac is not widely available in the homes of American children. By regularly dispensing it in the course of pediatric care, physicians could largely remedy this deficiency. 相似文献
54.
Anxiety sensitivity among children of parents with anxiety disorders: a controlled high-risk study 总被引:1,自引:0,他引:1
Mannuzza S Klein RG Moulton JL Scarfone N Malloy P Vosburg SK Klein DF 《Journal of anxiety disorders》2002,16(2):135-148
We investigated whether parental anxiety was related to anxiety sensitivity (AS) in offspring. Subjects were 261 offspring (aged 6-17 years) of parents with lifetime DSM-IV anxiety and/or mood disorders, and 79 offspring of parents with no lifetime anxiety, mood, or psychotic disorder. Parents and offspring were interviewed by blind clinicians. Children were administered the Child Anxiety Sensitivity Index (CASI). There were no significant differences between CASI scores of the offspring of parents with anxiety and/or mood disorders, and offspring of comparison parents. We conclude that parental anxiety or mood disorder does not predispose offspring to high anxiety sensitivity. 相似文献
55.
Waterston–Cooley anastomosis may be carried out in patients with tricuspid atresia to provide pulmonary perfusion. It is associated with several complications, including preferential blood flow to the right lung, hypoplasia of the left pulmonary artery, obstruction of the anatomosis or rupture of pulmonary aneurysms. We study a patient with thrombosis in the pulmonary arteries following surgical construction of a Waterston shunt in childhood. Imaging findings and clinical symptoms are discussed with emphasis on echocardiogram‐gated multislice spiral CT. 相似文献
56.
Victoria KM Tay Robert Fitridge Mark LH Tie 《Journal of Medical Imaging and Radiation Oncology》2002,46(2):163-166
Demographic, clinical and laboratory data were retrospectively collected from records of 146 cases of CT fluoroscopy‐guided chemical lumbar sympathectomy for the palliation of inoperable peripheral vascular disease (PVD) between January 1997 and August 1999. Of these, 16% had claudication, 39% had rest pain and 44% had ischaemic ulcers or gangrene. Seventy‐three percent of elective cases were outpatients. At 3 months, 27 cases were lost to follow up, leaving 119 cases. Within 3 months, improvement, defined as doubling of the walking distance, cessation of rest pain or healing of ulcers, occurred in 30.3% of cases. No change was observed in 45.4% of cases and 24.3% of cases deteriorated. Patients with ulcers or gangrene had significantly poorer results than those without any ischaemic lesions, as only 19% versus 39% of patients improved (P < 0.05). The presence of hypertension, diabetes mellitus, hyperlipidaemia and smoking had no value in predicting clinical outcome (P > 0.05). There were no major complications noted. CT fluoroscopy‐guided chemical lumbar sympathectomy is safe and effective, with a complication rate of less than 1%, and efficacy of at least 30% measured within 3 months. It is a simple and minimally invasive procedure, easily performed on an outpatient basis. CT fluoroscopy‐guided chemical lumbar sympathectomy should be considered for all patients in the early stages of inoperable PVD. 相似文献
57.
58.
Dietary zinc deficiency in rats induces hyperplasia in the esophagus and
increases N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor
incidence. Previous work showed a direct relationship between epithelial
cell proliferation and esophageal tumor incidence in rats given multiple
doses of NMBA. We investigated the effects of single low doses of NMBA in
zinc-deficient rats since a single dose of 5.0 mg/kg was reported to be
non-carcinogenic in rats. Zinc-sufficient and deficient rats received a
single i.g. dose of NMBA at 0.5 or 2.0 mg/kg. At week 14, tumor incidence
was 50% with 0.8 +/- 1.0 tumors/rat, and 80% with 2.2 +/- 1.9 tumors/rat,
in deficient groups, D(0.5) and D(2.0), that received the lower and higher
dose, respectively. In addition, two small papillomas were found in one out
of eight untreated zinc-deficient rats. None of the NMBA-treated or
untreated zinc- sufficient rats had any tumors. Esophageal cell
proliferation, as determined by proliferating cell nuclear antigen (PCNA)
immunohistochemistry, showed that, irrespective of NMBA treatment,
deficient esophagi had significant increases in the number of labeled
cells, the total number of cells, and the labeling index, as compared with
zinc-sufficient ones. Mutations in Ha-ras and p53 genes in esophageal
tumors were detected by single strand conformation polymorphism (SSCP)
analysis. DNA sequencing of variant conformers revealed a point mutation
(GGA-->GAA, codon 12) in Ha-ras in 4/5 (80%) and 5/8 (63%) tumors, from
D(0.5) and D(2.0) rats, respectively. Three out of eight tumors from D(2.0)
rats exhibited SSCP mobility shifts within p53 exons 5 and 7: two tumors
(2/8, 25%) had missense mutations and the third, a silent mutation. Of the
two tumors with p53 mutations, one had a double mutation (transition at
codon 164, TCA-->TTA; transversion at codon 241, AGT-->TGT), and the
other tumor, a transition at codon 172 (AGA-->GGA), with amino acid
changes in all cases. In parallel with PCNA expression, elevated p53
expression was associated with hyperplastic and dysplastic regions, as well
as with tumors, in deficient esophagi. In short, these data indicate that
dietary zinc deficiency, with its associated sustained increased cell
proliferation in the esophagus, can drive an otherwise non-tumorigenic dose
of NMBA into a highly tumorigenic one.
相似文献
59.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion. 相似文献