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41.
There is an evident imbalance between the number of patients awaiting a kidney transplant and the availability of organs proceeding from donors with brain death. A high number of patients die each day from heart failure, whose organs could be used for transplants if specific care is employed. Although centres do exist where these methods of extraction are established, the problems of organic damage have yet to be resolved, since one third of the organs are still lost, besides the increase in the need for early dialysis, and the number of dysfunctioning grafts two years after the transplant, when this type or organ is employed. There is increasingly detailed knowledge of the pathogenesis of organic damage following heart failure and reanimation, as well as of the damage following the conservation and reimplantation of the kidney. Knowledge of the maximum time of hot ischemic that an organ can withstand is of crucial importance if organs are not to be unduly discarded. Besides, the increasing understanding of the physiopathology of oxidative stress could make it possible for us, through the use of antioxidants, to attempt to improve the utilisation of the organs and diminish the incidence of dysfunctions and rejections. 相似文献
42.
Yuta Kobayashi Alberto Ricci Isidoro Rossodivita Francesco Amenta 《Naunyn-Schmiedeberg's archives of pharmacology》1994,349(6):559-564
In the present study, the pharmacological characteristics and the anatomical localization of dopamine D2-like receptor sites in the extraparenchymal and in the intraparenchymal portion of the rabbit pulmonary artery were investigated using combined radioligand binding and light microscope autoradiography with [3H]-spiroperidol (spiperone) as a ligand. The ligand was bound to sections of the pulmonary artery in a manner consistent with the labelling of dopamine D2-like receptors with an equilibrium dissociation constant (K
d) of about 2.4±0.07 nmol/l and a maximum density of binding sites of 65±4.5 fmol/mg tissue. In contrast, binding experiments made with sections of rabbit lung did not allow the evaluation of specific binding. Light microscope autoradiography showed the development of specific silver grains within the tunica adventitia of extraparenchymal branches of rabbit pulmonary artery and of large and, to a lesser extent, of medium-sized intraparenchymal branches of the pulmonary artery. No silver grains were found within small branches of the pulmonary artery or of the pulmonary vein. Development of adventitial silver grains was inhibited by compounds active at dopamine receptors. The greater sensitivity to displacement by domperidone, haloperidol, (–)-sulpiride and bromocriptine than to displacement byN-propyl-norapomorphine, quinpirole or clozapine suggests that the [3H]-spiroperidol binding sites observed in extraparenchymal, large and medium-sized branches of the pulmonary artery belong, probably, to the dopamine D2 receptor subtype. The possible pre-junctional localization of these sites is discussed.
Correspondence to: R Amenta 相似文献
43.
Background: Hybrid, combined or mixed bariatric surgery is the combination of a degree of ‘malabsorption’ (as achieved by the intestinal bypass) with a ‘rrestriction’
(as achieved by gastric bypass or gastroplasty), thereby simultaneously reducing the absorption of fats in the small bowel
and decreasing the intake of food. Methods: A modification of the bilio-pancreatic diversion (BPD) with a duodenal switch
procedure, vertical lineal gastrectomy and preservation of the pylorus, has been used in 23 patients. The antropyloric pump
and 4 cm of the duodenum are left intact to preserve physiologic gastric emptying and to prevent anastomotic ulcer. The use
of staplers and continuous running sutures reduces surgical risks and operative time. Results: One patient, converted from
a vertical gastroplasty, had an intrathoracic esophageal perforation and died of multisystemic organ failure, a mortality
rate of 4.5%. One patient had a partial dehiscence of the laparotomy wound. Three patients developed subcutaneous seromas.
Mean weight losses during the first 4 months were 13, 11, 6 and 5 kg, with a loss of 70% of excess weight in patients approaching
1 year. No patient needs treatment for diarrhea. No serious secondary side-effects have been detected. Conclusion: This operation
appears to result in very satisfactory weight loss, improved quality of life, and a low incidence of complications. 相似文献
44.
Adult-derived neural precursors transplanted into multiple regions in the adult brain 总被引:4,自引:0,他引:4
Neural stem cells persist in the adult brain subventricular zone (SVZ). These cells generate a large number of new neurons that migrate to the olfactory bulb, where they complete their differentiation. Here, we transplanted cells carrying beta-galactosidase under the control of neuron-specific enolase promoter (NSE::LacZ) from the SVZ of adult mice into the striatum cortex and olfactory bulb, with or without an excitotoxin lesion. Between 2 and 8 weeks after transplantation, grafted cells were present in the recipient regions, but extensive migration and differentiation into mature neurons of grafted cells were only observed in the olfactory bulb. Clusters of graft-derived neuroblasts forming chain-like structures were observed within or close to the grated sites in the cortex and striatum; electron microscopy confirmed that graft-derived cells in the olfactory bulb and a small number in the striatum were neurons. Surprisingly, most of the cells expressing NSE::LacZ outside the olfactory bulb were astrocytes. We conclude that primary precursors from the SVZ migrate and differentiate effectively only within the environment of the olfactory bulb. Only limited survival and differentiation were observed in other brain regions studied. 相似文献
45.
BACKGROUND: Adrenalectomy in Cushing's syndrome and disease involves particular risks and complications. The aim of the study was to compare the open posterior and the flank laparoscopic approaches in this group of patients. METHODS: Forty patients who underwent unilateral or bilateral adrenalectomy for hypercortisolism between 1991 and 1999 were studied. Patients were divided as follows: adenoma--5 laparoscopic and 6 open; hyperplasia--17 laparoscopic and 12 open. Demographics, surgical details, outcome, and complications were comparatively analyzed. RESULTS: Patients undergoing laparoscopic or open adrenalectomy were comparable in terms of age, sex distribution, body mass index, respiratory status, and anesthetic risk. Operative time was longer in the laparoscopic group. One patient in the laparoscopic group died of upper gastrointestinal tract bleeding on postoperative day 17. Two patients in the open group and one in the laparoscopic group experienced postoperative complications. Cure of the disease occurred in all patients. Mild abdominal wall pain developed in one patient in each group. No abdominal wall weakness was identified in either group. CONCLUSIONS: Cure rate and operative and long-term morbidity were similar for laparoscopic and open adrenalectomies in this series. However, it is important to emphasize that late complications in our patients who underwent the posterior open procedure were rather infrequent. 相似文献
46.
M F Herrera I D Hay P S Wu J R Goellner J J Ryan J R Ebersold E J Bergstralh C S Grant 《World journal of surgery》1992,16(4):669-74; discussion 774-5
The latest World Health Organization International Classification defines papillary thyroid carcinoma by its "follicular cell differentiation...as well as characteristic nuclear changes". However the oxyphilic (Hürthle cell) papillary carcinoma have nuclei which generally resemble the nuclei seen in oxyphilic follicular carcinomas, and such oxyphilic papillary tumors may behave more aggressively than typical papillary cancers. To further characterize these rare tumors, we identified during a 32-year period 22 patients with oxyphilic papillary cancer and compared them with 1,084 patients with typical papillary cancers and 57 patients with oxyphilic follicular cancers treated by the Mayo surgical group during the same time period. Although typical papillary and oxyphilic papillary cancers were comparable with regards to patient age, tumor size and extent, TNM stage, and prognostic score (AGES), there were significant differences. Compared to typical papillary tumors, oxyphilic papillary cancers had fewer neck nodal metastases at primary diagnosis (5% vs 40%, p less than 0.0001), were more often DNA non-diploid (71% vs 21%, p less than 0.001), and after 10 postoperative years had higher rates of both tumor recurrence (28% vs 11%, p less than 0.0001) and cause-specific mortality (1.7% vs 4%, p less than 0.0005). In these four important respects the oxyphilic papillary cancers more resembled the oxyphilic follicular cancers. For oxyphilic follicular cancers, the frequency of initial neck nodal metastases was 7% (cf 5%); 83% of the oxyphilic follicular tumors were non-diploid (cf 71%), and at 10 years postoperatively the tumor recurrence and cause-specific mortality rates were 28% and 18%, insignificantly different from 28% and 17% seen with the oxyphilic papillary cancers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
47.
Public Health System accepts "New Public Health" only in a theoretical way, since in the practice essential modifications to get "Health For All-2000" aims are not implemented. It is necessary to look "bridge-heads" that permit to introduce changes gradually to reorganize Health Services. In the present article, different alternatives are analyzed, all of them giving priority to the programmes that consider Health as a natural resource. These programmes can be "Governmental Programmes" so Health policies coming from the Health Department can be assumed by the others Public Administration Departments. 相似文献
48.
49.
Trilla Herrera E Torrecilla Ortíz C Muñoz Seguí J Riera Canals L Suárez Novo JF Marco Pérez LM Franco Miranda E Serrallach Milá N 《Actas urologicas espa?olas》2000,24(5):423-428
First described by the end of the fifties, pelvic lipomatosis is an uncommon disease that develops as a result of an excessive proliferation of benign fat tissue within the perivesical and perirectal spaces. The compressive effect on the urinary, and to a lesser degree, the digestive and vascular structures result in the well-known symptoms. Diagnosis is reached through X-ray studies, primarily computerised tomography. Contribution of four new cases in young males diagnosed through imaging studies as well as biopsies in three of them. Evolution has been varying, with medical control of symptoms in two cases and renal function impairment due to upper obstructive uropathy in the other two. 相似文献
50.