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71.
Bone sialoprotein (BSP), an osteogenic protein (OP), mixed with a carrier, was implanted in the pulp of rat first upper molars (OP group). Cavities were prepared with dental burs and pulp perforation was carried out by pressure with the tip of a steel probe. After 8, 14, and 30 days, the rats were killed and the pulps of the OP group were compared with (1) a sham group (S group), (2) a group where the carrier was implanted alone (C group), and (3) capping with calcium hydroxide (Ca group). After 8 days, a few inflammatory cells were seen, mostly located at the pulp surface near the perforation. In the Ca group, a dentin bridge started to form, in contrast to the other groups. After 15 days, globular structures were seen in the pulps of the S and C groups. A reparative osteodentin bridge isolated the pulp from the cavity in the Ca group. Variable reactions were seen in the OP group, with some evidence of cell and matrix alignments or plugs of osteodentin in continuity with an inner layer of reparative dentin. After 30 days, irregular osteodentin formation was observed in the pulps of the S and C groups, with a tendency for globular structures to merge, but with interglobular spaces filled by pulp remnants. In the Ca group, osteodentin was observed in the mesial part of the pulp chamber. In the BSP-implanted group, the osteogenic protein stimulated the formation of a homogeneous dentin-like deposit occupying most of the mesial part of the pulp. Apparently, BSP stimulates the differentiation of cells which secrete an organized extracellular matrix more efficiently than any other capping material used so far. Altogether, the results reported here support that bone sialoprotein displays novel bioactive properties and is capable of stimulating in 1 month’s time the development of a thick reparative dentinal tissue in the pulp, occluding the perforation and filling the mesial third of the pulp chamber. Received: 13 October 1999 / Accepted: 6 December 1999  相似文献   
72.
An unusual case of cholelithiasis in an 18–month-old boy with cervico-oculo-acoustic (Wildervanck's) syndrome is presented. Our patient had Duane's retraction syndrome, Klippel-Feil anomaly and congenital deafness. To our knowledge this is the first case in which a probable association between cholelithiasis and Wildervanck's syndrome has been recorded. On the other hand, the presence of mutual malformations and anomalies such as scoliosis, ventricular septal defect, ectopic kidney, hydrocephalus, hypoplastic thumb and growth retardation seems to suggest that Wildervanck's syndrome is a clinical variant of Klippel-Feil sequence.  相似文献   
73.
Background: Researchers have paid scant attention to comparative studies of quality of life (QOL) issues among psychiatric diagnostic groups; the studies of patient – caregiver concordance ratings had small sample sizes; and the reports are rare from the African and Arab worlds. Objectives: to assess the subjective QOL of stable Sudanese outpatients, using the WHOQOL – Bref, compared with a general population sample; examine the caregiver–patient concordance; and assess the variables that impact on domains of QOL. Method: The responses of outpatients with schizophrenia (99), major affective disorders (120) and neuroses (81) (mean age 33.8) were compared with 211 controls and the impression of their family caregivers. Results: Patients were dissatisfied with life circumstances; the schizophrenia group and those with co-morbidity had significantly lower QOL scores; while the control group had higher QOL scores. There was no significant impact on QOL domains, of socio-demographic factors, duration of illness and treatment side effects. The schizophrenia group had least concordance with caregivers, but eight items were judged to be satisfactorily concordant for all groups. Conclusions: Psychiatric patients in stable condition can make reliable judgments of QOL, with relatives providing additional information. Differences in QOL and concordance of ratings reflect disease severity.  相似文献   
74.
Subarachnoid hemorrhage (SAH) of spinal origin is a rare entity accounting for approximately 1% of all cases of SAH. Its most frequent causes are trauma and vascular malformations. Although primary spinal tumors, especially ependymomas, are also relatively common causes, SAH secondary to a metastatic spinal tumor arising from outside the central nervous system is an extremely rare condition; only one case has been reported in the literature. The authors present a case of spinal meningeal carcinomatosis secondary to cutaneous malignant melanoma in which the patient presented with only symptoms of SAH. Although very rare, this case underscores several factors. 1) Spinal SAH due to spinal metastases should be considered in the differential diagnosis of patients with previously known malignancy. 2) Spinal SAH may manifest without paraparesis or sensory deficit. 3) Magnetic resonance imaging of the spinal cord may be important to determine the source of SAH in patients in whom four-vessel cerebral angiography demonstrates no abnormal findings.  相似文献   
75.
A 17-month-old boy presented with failure to thrive, polyuria, and vomiting. He had been diagnosed clinically with nephrogenic diabetes insipidus and treated by amiloride and hydrochlorothiazide combination without a satisfactory outcome at another center since 1 year of age. The diagnosis was confirmed by genetic analysis (AVPR2mutation), and the treatment was modified to include rofecoxib (a selective cyclooxygenase-2 inhibitor) in addition to hydrochlorothiazide and amiloride. This combination along with a low-salt diet resulted in a dramatic decrease in urinary free-water loss, while no side effect was noted. Because of prohibition of rofecoxib, it had to be substituted first by indomethacin and then by ibuprofen. However, both drugs were ineffective in controlling water diuresis. Thus, we had to replace these drugs by celecoxib (another selective cyclooxygenase-2 inhibitor). We conclude that the combination hydrochlorothiazide/amiloride/cyclooxygenase-2 inhibitor could be successfully used to treat congenital nephrogenic diabetes insipidus.  相似文献   
76.
77.
Humans have been exposed to blast effects since the invention of gunpowder and explosives. Bronchial injury because of an explosion is a rare but lethal injury that requires prompt recognition and treatment. In this article, we present a case of a bronchial tear after an explosion.  相似文献   
78.
Acetyl-CoA carboxylases (ACC1 and ACC2) catalyze the carboxylation of acetyl-CoA to form malonyl-CoA, an intermediate metabolite that plays a pivotal role in the regulation of fatty acid metabolism. We previously reported that ACC2 null mice are viable, and that ACC2 plays an important role in the regulation of fatty acid oxidation through the inhibition of carnitine palmitoyltransferase I, a mitochondrial component of the fatty-acyl shuttle system. Herein, we used gene targeting to knock out the ACC1 gene. The heterozygous mutant mice (Acc1(+/-)) had normal fertility and lifespans and maintained a similar body weight to that of their wild-type cohorts. The mRNA level of ACC1 in the tissues of Acc1(+/-) mice was half that of the wild type; however, the protein level of ACC1 and the total malonyl-CoA level were similar. In addition, there was no difference in the acetate incorporation into fatty acids nor in the fatty acid oxidation between the hepatocytes of Acc1(+/-) mice and those of the wild type. In contrast to Acc2(-/-) mice, Acc1(-/-) mice were not detected after mating. Timed pregnancies of heterozygotes revealed that Acc(-/-) embryos are already undeveloped at embryonic day (E)7.5, they die by E8.5, and are completely resorbed at E11.5. Our previous results of the ACC2 knockout mice and current studies of ACC1 knockout mice further confirm our hypotheses that malonyl-CoA exists in two independent pools, and that ACC1 and ACC2 have distinct roles in fatty acid metabolism.  相似文献   
79.
80.
Gingival fibromatosis represents the fibrous hyperplasia of the gingival tissue. Clinical examination reveals enlargement of buccal and palatal gingival tissue. Many forms of gingival fibromatosis are of unknown etiology and termed as idiopathic gingival fibromatosis. However, several authors use various terms such as gingivomatosis and elephantiasis to describe these lesions. Our aim in this case report is to present five patients (one female, four males) with unusual clinical forms of gingival hyperplasia and to discuss the histopathological and clinical features in comparison to similar enlargements. Clinical examinations did not reveal increased periodontal pocket depths, besides plaque and gingival index scores were found to be in normal range. All of the patients were systemically healthy and were not subject to medications, which could lead to gingival hyperplasia. Additionally, clinical appearance of the lesions did not show any signs of trauma. Excisional biopsies were performed in all cases. The pathological examinations of the specimens demonstrated fibroconnective tissue characteristics, which were in accordance with the clinical appearance of all patients. Lesions healed successfully without sequelae or infection, and no recurrence was observed after 1-year follow-up.  相似文献   
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