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41.
Tuberous sclerosis: characteristics at CT and MR imaging   总被引:7,自引:0,他引:7  
Altman  NR; Purser  RK; Post  MJ 《Radiology》1988,167(2):527-532
Computed tomography (CT) and magnetic resonance (MR) imaging findings were reviewed in 26 patients with tuberous sclerosis. All patients underwent CT; 16 patients underwent both. The CT features included subependymal nodules in 25 of 26 patients (96%) and calcifications in 23 of 26 (88%). Parenchymal hamartomas (cortical tubers) were seen in 23 of 26 patients (88%). These lesions had less attenuation than surrounding brain in 16 of 26 patients (62%) and were calcified in 14 of 26 patients (54%). Contrast enhancement of a lesion, indicating a subependymal giant cell astrocytoma, occurred in three of 26 patients (12%). The MR imaging characteristics included subependymal nodules (periventricular nodules) of intermediate signal intensity in ten of the 16 patients (63%). Parenchymal hamartomas, demonstrated in 15 of the 16 patients (94%), usually exhibited long T1 and T2 relaxation characteristics. The pattern was noted to be reversed in the two newborn patients (13%). One parent demonstrated a forme fruste at CT but had a normal MR image.  相似文献   
42.
A study of 140 days duration was performed to examine if human male volunteers (n = 5) respond to ovine follicle stimulating hormone (oFSH) immunization (administered adsorbed on Alugel on days 1, 20, 40 and 70) by producing antibodies capable of both binding and neutralizing bioactivity of human FSH. The kinetics of antibody production for both the immunogen (oFSH) and the cross-reactive antigen (hFSH) were essentially similar. The volunteers responded only to the first two immunizations. The boosters given on days 40 and 70 were ineffective, probably because of the presence of substantial amounts of circulating antibody to oFSH. Of the antibodies generated to oFSH, 25-45% bound hFSH with a mean binding affinity of 0.65 x 10(9) +/- 0.53 M(-1). The binding capacities at the time of high (30-80 days of immunization) and low (>110 days) titres were 346 +/- 185 and 10.5 +/- 5.8 ng hFSH/ml respectively. During the period of high titre, free serum FSH (value in normal males 1-5 ng/ml) was not monitorable. A 50 microl aliquot of the antiserum obtained from different volunteers between days 30 and 80 and on day 140 blocked binding of (125)I-labelled hFSH to its receptor by 82 +/- 9.7 and 53 +/- 12.2% respectively. The antibody produced was specific for FSH, and no significant change in the values of related glycoprotein hormones (luteinizing hormone/testosterone and thyroid stimulating hormone/thyroxine) were recorded. Seminal plasma transferrin, a marker of Sertoli cell as well as of seminiferous tubular function, showed marked reduction (30-90%) following immunization with oFSH. Considering that endogenous FSH remained neutralized for approximately one sperm cycle only (65 days), the reduction in sperm counts (30-74%) exhibited by some volunteers is encouraging. Immunization with oFSH did not result in any significant changes in haematology, serum biochemistry or hormonal profiles. There was no production of antibodies capable of interacting with non- specific tissues. It is concluded that it should be possible to obtain a sustained long-term blockade of endogenous FSH action in men by using oFSH as an immunogen. This is a prerequisite for obtaining significant reduction in the quality and quantity of spermatozoa produced, thus leading to infertility.   相似文献   
43.
One thousand and thirty-one singleton children of teenage mothers were compared with 10 950 singleton children of older mothers in a national longitudinal cohort study. Children born to teenage mothers and living with them during the first 5 years were more liable to hospital admissions, especially after accidents and for gastroenteritis, than were children born to and living with older mothers. Frequent accidents, poisoning, burns, and superficial injuries or lacerations were more often reported by teenage mothers. The association of teenage mothering with greater likelihood that children would have accidents or be admitted to hospital remained highly significant even after controlling for social and biological confounding influences. Although in part a marker for adverse socioeconomic circumstances, low maternal age appears to be a health hazard for children.  相似文献   
44.
SUMMARY A 23-year-old man, previously fit and well, presented with an atypical pneumonia, associated with microangiopathic anaemia, thrombocytopenia, rhabdomyolysis and renal impairment. Despite administration of intravenous fluids and antibiotics, his condition rapidly deteriorated, and the possibility of an aggressive connective tissue disorder was raised. Thus he was treated with high-dose oral steroids and plasma exchange until autoantibodies were shown to be negative. At this stage it transpired that the patient had swallowed water from a stream three weeks earlier, and leptospira antibody titres were subsequently found to be elevated. Antibiotics were continued, and after a protracted course he made a full recovery. Leptospirosis should be remembered as a rare cause of atypical pneumonia, particularly if there is associated hepatic or renal impairment.  相似文献   
45.
Two cases of nonmalignant adrenal masses with prolonged T2 relaxation time and increased adrenal/liver signal ratios are reported. These two cases, one a functioning adenoma with small areas of hemorrhage and the other tuberculosis, emphasize that increased signal intensity in an adrenal mass on T2-weighted images is not always due to malignancy or a pheochromocytoma. While the signal characteristics of an adrenal mass are useful in distinguishing malignancy or pheochromocytoma from benign adenomas, other studies (such as computed tomography for the detection of hemorrhage), clinical evaluation, and percutaneous biopsy remain useful in the investigation of an adrenal mass.  相似文献   
46.
The choice of a contrast agent for pulmonary angiography has important implications for patient comfort, image quality, and perhaps the safety of the procedure, particularly for "high-risk" patients. In a prospective study the nonionic, low-osmolality agent iopamidol eliminated the problem of image degradation due to coughing, and patients showed excellent tolerance for it. However, pressure measurements obtained within 3-5 minutes of injection of iopamidol and diatrizoate sodium meglumine 76% showed no significant difference in the hemodynamic effects of the two contrast agents, either for normotensive or for pulmonary hypertensive patients. Contrary to a common presumption, pulmonary hypertension by itself did not appear to increase the risk of pulmonary angiography. The theoretic presumption of greater hemodynamic stability with low-osmolality contrast agents was not clinically evident in this trial with iopamidol. At present, enhanced patient comfort and improved image quality remain the only confirmed bases for choosing this contrast agent for pulmonary angiography.  相似文献   
47.
Gilbert syndrome is a common genetic disorder associated with mild unconjugated hyperbilirubinemia and no clinical illness. In contrast, Crigler-Najjar syndrome types I and II are rare genetic disorders associated with severe unconjugated hyperbilirubinemia and a life-long risk of kernicterus. Patients with Gilbert syndrome have low levels of a normal form of uridinediphosphoglucuronate glucuronosyltransferase because of a defect in the promoter region of both alleles, whereas patients with Crigler-Najjar syndrome are homozygous for a defect that yields an abnormal form of the enzyme that has limited or no activity. This case report describes a young adult with Crigler-Najjar syndrome type II in whom kernicterus developed after a laparoscopic cholecystectomy. The development of kernicterus was the result of a largely preventable series of events that lead to an increase in the free fraction of his serum bilirubin. Analysis of his genetic defect showed that he was homozygous for the mutation associated with Gilbert syndrome and heterozygous for a second mutation in the open reading frame of one allele of the bilirubin uridinediphosphoglucuronate glucuronosyltransferase gene. The combined defect leads to severe hyperbilirubinemia and shows how seemingly benign genetic defects, when combined, can cause serious clinical disease. (Gastroenterology 1997 Jun;112(6):2099-103)  相似文献   
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