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61.
The genetic features of a series of 227 patients with hereditary motor and sensory neuropathy (HMSN) have been analysed. The series comprised 119 index cases from 110 families in which 108 affected relatives were identified. The cases were classified as having type I or type II HMSN on the basis of nerve conduction studies. Inheritance in the type I cases was autosomal dominant in 139 (45 families) and autosomal recessive in eight (four families) with 26 single cases. For the type II cases, 35 (17 families) were autosomal dominant and three (two families) autosomal recessive with 16 single cases. A significant excess of males was present in the combined single and recessive type I cases and in the type I index cases. No X linked pedigrees were identified.  相似文献   
62.
Isolated single myocytes were prepared from myocardium of developing ventricular aneurysms and from myocardium within the scar of chronic ventricular aneurysms. The morphology and function of the individual cells were compared. The cells from developing aneurysms were rod-shaped, with a distinct sarcomeric structure, but did not contract even in the presence of high calcium concentrations. The sarcomere length was significantly higher than that of cells from chronic aneurysms and approached the theoretical point at which no contraction can occur. Cells from chronic aneurysms were either rod-shaped and contractile, or rounded due to hypercontracture of the myofilaments. Electron microscopy of cells from developing aneurysms confirmed the presence of elongated sarcomeres, a loss of the actin-myosin interdigitation, and damage to the contractile proteins which was particularly evident in the thin filaments. Cells with similar characteristics have also been isolated from a ruptured, ischaemic papillary muscle. These changes, which are due either to ischaemia or to overstretching of cells, may account for the weakness of the wall of developing aneurysms and be a cause of rupture or enlargement.  相似文献   
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Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
65.
In order to test the regenerative capacity of atrophic axons, a constricting ligature was placed around the proximal tibial nerve of the rabbit, and the nerve crushed at the ankle one week later. Axonal atrophy with altered g ratios was subsequently confirmed in fibres distal to the site of ligature and proximal to the site of crush. In nerves with tight proximal ligatures the reinnervation of plantar muscles and the subsequent recovery of distal motor latency were delayed, indicating impaired regeneration. This result may be relevant to the "double-crush" theory of nerve damage.  相似文献   
66.
Crohn's disease (regional enteritis) is a chronic inflammatory disease of the bowel with well-documented clinical manifestations and complications. This report of a 35-year-old woman with Crohn's disease outlines the clinical presentation and studies illustrating "quiescent" regional enteritis. The patient was treated for one of the complications of this disease entity. She was referred to the orthopedic clinic with symptoms of lumbar disc syndrome, as well as a painful hip. Crohn's disease was diagnosed and assumed to be well controlled. Physical examination revealed a subgluteal abscess, ostensibly caused by Crohn's disease. The abscess fistulized through the greater sciatic notch. The capricious nature of this disease entity is self-evident.  相似文献   
67.
Introduction: Giant omphaloceles can be a challenge for pediatric surgeons and neonatologists worldwide. It is a rare and low-frequency congenital anomaly with no standardized management schemes or treatment protocols. Over the past few decades, we have developed a simple and efficient staged management for giant omphaloceles that allows definitive closure in the neonatal period, the results of which we outline in this report.Material and methods: With IRB approval, a retrospective and multicentric cohort study was carried out between 1994 and 2019 with patients with giant omphalocele defined as an abdominal wall defect greater than 5 cm in diameter and/or that contains more than 50% of the liver within the sac. We included all patients managed with the nonsurgical silo technique. Data on demographics, gestational age, associated malformations, amnion reduction and inversion time, anatomic closure, requirement of a mesh, intra- and post-silo complications, mortality and follow-up were collected. The technique consists of the construction of a silo with an adhesive hydrocolloid dressing (Duoderm?) to achieve an omphalocele staged-reduction until complete abdominal reintegration of the liver and bowel preservation of the amnion sac. This also enables the simulation of abdominal closure before definitive surgical closure, being managed in the neonatal intensive care unit (NICU).Results: Forty patients, 21 of whom were female, were managed with this technique. The average weight was 2900 gs (890–3900), and the median gestational age was 38 weeks (28–40). In total, 37.5% of cases had an associated comorbidity. The average silo reduction time was 7.3 days (0–35), the average time of amnion inversion was 5 days (2–9), and the average time to closure was 14.6 days (6–38). Anatomical closure was achieved in 95% of cases. In 4 patients, an absorbable mesh was used to reinforce the anatomical closure, and in 2 patients (5%), a mesh (Dualmesh?) was required to achieve an abdominal closure. There was no mortality associated with this nonsurgical silo technique. The average follow-up time was 60 (6 - 288) months.Conclusion: The staged silo management of giant omphalocele in this series is safe and effective and reduces the time to closure and potential morbidity and mortality compared with traditional surgical or medical management.  相似文献   
68.
Injuries to the bladder and ureter are uncommon but usually require prompt urological management. Due to their infrequent nature, Urologists maybe unfamiliar with managing these acute problems and may not work in specialist centres with readily available expertise in open and abdominal surgery. We aim to provide advice in the form of a consensus statement led by the Female, Neurological and Urodynamic Urology (FNUU) Section of the British Association of Urological Surgeons (BAUS), in consultation with BAUS members and consultants working in units throughout the UK, to create a comprehensive management pathway and a series of statements to aid clinicians.  相似文献   
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70.
Central motor conduction to the small hand muscles was investigated in 59 patients with peroneal muscular atrophy and hereditary spastic paraplegia (HSP) by using transcranial magnetic brain stimulation. These comprised 20 patients with type I hereditary motor and sensory neuropathy (HMSN I), 15 with type II (HMSN II), 4 with HMSN I and 10 with HMSN II with associated pyramidal features, and 10 with the "pure" form of HSP. Central motor conduction was usually normal in HMSN I, HMSN II, and HSP. In HMSN I with pyramidal signs, central motor conduction time was greatly prolonged bilaterally. This result may reflect an associated involvement of the central motor pathways in these patients. In HMSN II with accompanying pyramidal features, 6 of the 10 patients had abnormal central motor conduction, although conduction times were only slightly prolonged, suggesting a different pathophysiological pattern.  相似文献   
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