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241.
242.
Cypermethrin is widely used as an insecticide on animals and in agriculture, the home, and the garden. The effect of inhaled cypermethrin on the cardiac mechanics, electrophysiology, and ultrastructure in frogs was investigated in this study. Four groups received 100 microL of cypermethrin via inhalation for different exposure times, and one group was used as a control. Electrical and mechanical activities of the heart were recorded, and heart samples were examined at light and transmission electron microscopic levels for all groups. The atrial and ventricular contractile forces on the mechanogram, the amplitude of the P wave and the QRS complex on electrocardiogram, and the heart rate were significantly decreased in cypermethrin-inhalated frogs. The total duration of contraction was prolonged in the study groups. Ultrastructurally, dilatation in smooth endoplasmic reticulum cisterns, a decrease in the number of mitochondria, disorganization in the myofibrils of myocytes, and necrotic changes in endothelial cells were observed. These results suggest that cypermethrin has cardiotoxic effects that increase with exposure time. 相似文献
243.
Hepatic malignancies: improved treatment with intraarterial Y-90 总被引:4,自引:0,他引:4
Herba MJ; Illescas FF; Thirlwell MP; Boos GJ; Rosenthall L; Atri M; Bret PM 《Radiology》1988,169(2):311-314
An improved treatment method for hepatic malignancies with yttrium-90 incorporated into the matrix of glass microspheres was evaluated prospectively. Fifteen patients with 12 metastatic colorectal cancers, one carcinoid, one islet cell tumor, and one hepatoma were treated with three dose levels: 5,000 cGy (5,000 rad), ten patients; 7,500 cGy (7,500 rad), three patients; and 10,000 cGy (10,000 rad), two patients. Mean follow-up was 7 months (range, 2-12 months). Stable disease in the liver was seen in ten patients, four of whom had concurrent progression of extrahepatic disease, which resulted in two deaths. Two additional deaths were not directly related to the malignant process. Progression of liver disease was found in five patients, with three deaths occurring at 7-8 months. No procedural, hematologic, or pulmonary complications occurred. Late gastroduodenal ulceration occurred at 6-8 weeks in three patients who had histories of chronic alcohol abuse. This method of therapy seems to be feasible and efficient. Caution is necessary with high doses or with patients with a history of or predisposition to gastroduodenal ulcers. 相似文献
244.
Diana Barlow Dip. Med. Tech. Norma Saxe FF Derm SA 《International journal of dermatology》1988,27(6):388-390
Tinea capitis is regarded as rare in healthy adults. A study of 46 adults presenting with scalp problems with no other identifiable cause and 26 asymptomatic adult contacts of children with tinea capitis was undertaken. The confirmation of tinea capitis in 9 of 46 patients and 5 carriers among 26 adult contacts suggests that tinea capitis may affect healthy adults more often than was supposed. Further epidemiologic studies may be of interest. 相似文献
245.
A new hematopoietic cell line derived from a patient with Philadelphia chromosome (Ph1)-negative myeloblastic leukemia arising from a form of myelodysplastic syndrome (MDS) is described. This cell line, designated TMM, consists of immature cells with the morphological characteristics of young myeloblasts and grows in suspension culture with a doubling time of about 30 hours. By cytochemical analysis the cultured cells were positive for acid phosphatase. They were free of the Epstein-Barr virus-associated nuclear antigen as well as terminal deoxynucleotidyl transferase. Further phenotypic analysis revealed the expression of the myelomonocytic-specific antigen Leu-M1 and receptors for the Fc portion of IgG. Partial differentiation of these cells could be induced by dimethyl sulfoxide, tetradecanoyl phorbol acetate, or hypoxanthine and resulted in cells of the myeloid series expressing lysozyme and receptors for the C3b complement protein. The karyotype was 46,XY, lacked the Ph1 chromosome, and displayed no abnormalities at the light microscopic level. No rearrangement of the bcr-c-abl gene complex was found. This cell line should be useful for studying an important type of the heterogeneous population constituting Ph1-negative myeloblastic leukemia, arising in this instance from MDS, as well as for studying differentiation and proliferation of human pluripotent stem cells. 相似文献
246.
247.
FF Rubaltelli C Dani MF Reali G Bertini L Wiechmann M Tangucci A Spagnolo and the Italian Group of Neonatal Pneumology 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(12):1261-1268
A prospective multicentre 12-month survey of neonatal respiratory disorders in 63 537 Italian infants was performed to evaluate the incidence of acute neonatal respiratory disorders and of the main related complications. A total of 1427 developed respiratory disorders (2.2%), 208 of whom died (14.6%). The incidence of respiratory distress syndrome was 1.16%, with a case fatality rate (CFR) of 24%; that of transient tachypnoea was 0.93%, with a CFR of 1.3%. The rates of meconium aspiration syndrome, persistent pulmonary hypertension and pneumonia were 0.06%, 0.02% and 0.07%, with CFRs of 10.3%, 38.5% and 21.7%, respectively. The occurrences of the main complications in affected newborns were: bronchopulmonary dysplasia 5.6%, necrotizing enterocolitis 1.7%, patent ductus arteriosus 9.8%, 3o and 4o grade intraventricular haemorrhage 6.8% and air leak 4.9%. It was concluded that the incidence of acute neonatal respiratory disorders and the main related complications was lower than that reported two decades ago and that the CFR of acute neonatal respiratory disorders had increased. These results may be the consequences of (i) progress in the management of high-risk pregnancies, (ii) an increased number of viable infants with extremely low birth weight and (iii) diffusion of antenatal treatment with corticosteroids which, in this series, seemed to reduce the morbidity but not the mortality in the high-risk infants. 相似文献
248.
249.
FF Coppolino G Gatta G Di Grezia A Reginelli F Iacobellis G Vallone M Giganti EA Genovese 《Critical Ultrasound Journal》2013,5(Z1):S4
Gastrointestinal tract perforations can occur for various causes such as peptic ulcer, inflammatory disease, blunt or penetrating trauma, iatrogenic factors, foreign body or a neoplasm that require an early recognition and, often, a surgical treatment.Ultrasonography could be useful as an initial diagnostic test to determine, in various cases the presence and, sometimes, the cause of the pneumoperitoneum.The main sonographic sign of perforation is free intraperitoneal air, resulting in an increased echogenicity of a peritoneal stripe associated with multiple reflection artifacts and characteristic comet-tail appearance.It is best detected using linear probes in the right upper quadrant between the anterior abdominal wall, in the prehepatic space.Direct sign of perforation may be detectable, particularly if they are associated with other sonographic abnormalities, called indirect signs, like thickened bowel loop and air bubbles in ascitic fluid or in a localized fluid collection, bowel or gallbladder thickened wall associated with decreased bowel motility or ileus.Neverthless, this exam has its own pitfalls. It is strongly operator-dependant; some machines have low-quality images that may not able to detect intraperitoneal free air; furthermore, some patients may be less cooperative to allow for scanning of different regions; sonography is also difficult in obese patients and with those having subcutaneous emphysema. Although CT has more accuracy in the detection of the site of perforation, ultrasound may be particularly useful also in patient groups where radiation burden should be limited notably children and pregnant women. 相似文献
250.
Burak Kaymaz O. Ahmet Atay F. Bilge Ergen M. Ugur Mermerkaya Z. Deniz Olgun Kıvanc Atesok M. Nedim Doral 《Knee surgery, sports traumatology, arthroscopy》2013,21(8):1841-1848