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161.
An asymptomatic transsphenoidal meningoencephalocele was discovered incidentally by fiber laryngoscopic examination in a 62-year-old man suffering from hoarseness due to dysplasia of the vocal cord epithelium. To provide a better understanding of the pathogenesis of this anomaly, we performed histologic observations of paraffin-embedded specimens of 42 human fetal heads at 12–16 weeks of gestation. At these stages, ossification had started in the clivus but the sphenoid sinus was not developed. In contrast to the very low incidence of the intra- or trans-sphenoidal remnant of Rathke’s pouch after birth, we found (1) the typical mid-line cleft of the sphenoid body in two specimens (2/42 or 4.8 %) and (2) a duct-like, sellar inferior protrusion ending in the sphenoid body in 12 specimens (12/42 or 28.6 %). The cyst-like structure in the protrusion (two specimens) seemed to be composed of obstructed veins. The intra- and trans-sphenoidal anomalies were observed more frequently in specimens without ossification of the sphenoid body than in those with ossification. However, irrespective of ossification, a cyst-like remnant of the most upper part of Rathke’s pouch was always seen between the anterior and posterior lobes of the developing pituitary gland. In addition, the bursa pharyngea was seen in four specimens and we confirmed that the notochord was attached to the bursa in each case. The consistent remnant of the intrasellar Rathke’s pouch appeared to explain the high incidence of Rathke’s cleft cyst in adults. The relatively high incidence of intrasphenoidal anomalies in fetuses (14/42) suggested that the intra- or trans-sphenoidal remnant of Rathke’s pouch was physiologically closed by ossification of the sphenoid body.  相似文献   
162.
We aimed at evaluating the adequacy of the commonly employed compartmental model for quantitation of cerebral metabolic rate of oxygen (CMRO2) using 15O-labeled oxygen (15O2) and positron emission tomography (PET). Sequential PET imaging was carried out on monkeys following slow bolus injection of blood samples containing 15O2–oxyhemoglobin (15O2–Hb), 15O-labeled water (H215O), and C15O-labeled hemoglobin (C15O–Hb) into the internal carotid artery (ICA). Clearance slopes were assessed in the middle cerebral artery territory of the injected hemisphere. The time–activity curves were bi-exponential for both 15O2–Hb and H215O. Single exponential fitting to the early (5 to 40 seconds) and late (80 to 240 seconds) periods after the peak was performed and the 15O2–Hb and H215O results were compared. It was found that a significant difference between the clearance rates of the 15O2–Hb and H215O injections is unlikely, which supports the mathematical model that is widely used to describe the kinetics of 15O2–Hb and H215O in cerebral tissues and is the basis of recent approaches to simultaneously assess CMRO2 and cerebral blood flow in a single PET session. However, it should be noted that more data are necessary to unequivocally confirm the result.  相似文献   
163.
We report a case of retroesophageal right subclavian artery identified in a 59-year-old Japanese female during routine dissection in Nagasaki University School of Medicine. This kind of variation is relatively rare; however, reports of such cases have accumulated. We paid attention to the intersegmental arteries and above all, the second intercostal artery. On the other hand, there have been reports of a retroesophageal right vertebral artery, although such cases are extremely rare. It is considered that both retroesophageal arteries are formed by similar mechanisms. In other words, the distal part of the right dorsal aorta remained in such cases. However, in the case of a retroesophageal right vertebral artery, there might be the possibility of intercostal arteries developing into the vertebral artery, and we discuss such points here.  相似文献   
164.
We report a case of thoracic aortic aneurysm and aortic valve stenosis with chronic renal failure requiring hemodialysis. A 75-year-old man complained of back pain and hoarseness. He had been on dialysis for 15 years. A computed tomography scan of the chest showed marked calcification in the thoracic aortic arch, which is known as a porcelain aorta, and a distal arch aneurysm. Echocardiographic examination showed moderate aortic valve stenosis with calcification. An operation was scheduled, and both the aortic valve and the aortic arch aneurysm were successfully replaced with a mechanical valve and a prosthetic graft. Cardiovascular surgery for patients complicated by a porcelain aorta requires extra cares for the establishment of cardiopulmonary bypass and anastomoses of the aorta.  相似文献   
165.
166.
We report a 51‐year‐old female with Pick’s disease with Pick bodies (PDPB) showing a brainweight of 530 g. This case was considered to be a very rare case of PDPB, in which the lesion developed in the temporal and frontal lobes and later spread to the parietal lobe, occipital lobe, brainstem, cerebellum and spinal cord. This case showed very atypical clinicopathological findings. Clinically, bulging eyes and myoclonus were observed. Neuropathologically, Pick bodies were widely distributed beyond the usual distribution areas to the parietal cortices, occipital cortices, dentate nuclei, motor neuron nuclei in the brain stem, and spinal cord. The atypical clinical symptoms and the widespread neuropathological abnormalities observed in this case seem to represent an extremely extended form of PDPB.  相似文献   
167.
There is a subset of very elderly patients with senile dementia in whom abundant neurofibrillary tangles are present, mainly in the hippocampal region, without a significant number of senile plaques. In a retrospective neuropathological examination of 239 dementia patients, 14 were found to have this type of senile dementia. The apolipoprotein E ?2, ?3, and ?4 allele frequencies in this patient group were 0.39, 0.50, and 0.11, respectively. Such a high frequency of the ?2 allele suggests that this type of dementia is distinct from Alzheimer's disease not only from a neuropathological but also from a genetic viewpoint.  相似文献   
168.
Objectives Sumo wrestling is one of the most popular sports in Japan. Injuries are not uncommon as this is a vigorous contact sport. Sumo wrestlers have little in the way of protective clothing; their main garb is the mawashi, making them prone to exposure to any microorganisms in the dohyo. The bacterial flora of the dohyo has received little attention. If the constituent flora is identified, then appropriate treatment or prevention of any bacterial lesions or infections incurred by the wrestlers is possible. Methods The Vitek AMS system used in this study was developed by McDonnell Douglas Corporation. In this system, the physiological and biochemical properties of Gram-positive and negative bacilli, Gram-positive and-negative cocci, and fungi isolated from clinical materials and environments are examined using test cards specifically for each microorganism group, and the results are automatically read by a computer and encoded. Obtained codes are compared with a built-in database, and bacterial species of test strains are identified. Results In this study, using the automatic identification kit VITEK or ATB, we describe the aerobic bacterial flora found in the dohyo over the four seasons of the year. We also investigated the effect of salt on the bacterial flora as sumo wrestlers toss salt on the dohyo before each match. We show the relationship between salinity changes and variations in the flora observed upon the addition of salt. Without salt, at the beginning of a match, Gram-negative bacteria predominate. When salt is added, there is a transient decrease in the incidence of flora followed by an increase in the incidence Grampositive cocci. Conclusions Sixteen bacterial genera were identified using the bacterial identification systems in dohyo soil samples during the year. The number of identified bacterial species was 32. Even in the presence of salt, there is a measurable amount of bacterial flora in dohyo soil; salt does not act as an antibacterial agent.  相似文献   
169.
The in vitro antibacterial activity of OPC-17116, a new fluoroquinolone, against a wide variety of clinical isolates was evaluated and compared with those of ciprofloxacin, ofloxacin, and norfloxacin. OPC-17116 showed potent broad-spectrum activity against gram-positive and -negative bacteria. The activity of this compound against gram-positive bacteria was higher than those of other quinolones, and its activity against gram-negative and anaerobic bacteria was roughly comparable to those of other quinolones. OPC-17116 had potent activity against important pathogens of respiratory tract infections such as Staphylococcus aureus, Streptococcus pneumoniae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Haemophilus influenzae, and Branhamella catarrhalis. The MICs of this compound against 90% of these organisms, except for methicillin-resistant S. aureus, ranged from less than or equal to 0.006 to 3.13 micrograms/ml. OPC-17116 at more than one-half the MICs was bactericidal against clinical isolates of S. aureus, Escherichia coli, K. pneumoniae, and P. aeruginosa. The activity of OPC-17116 was decreased by several culture conditions such as acidic pH, high concentration of Mg2+ ions, and inoculum size of 10(7) CFU/ml. OPC-17116 inhibited the supercoiling activity of DNA gyrases from E. coli KL-16 and S. aureus SA113 (50% inhibitory concentrations, 0.19 and 23.0 micrograms/ml, respectively). The amount of OPC-17116 accumulation was higher than that of other quinolones in S. aureus.  相似文献   
170.
The patient was a 72‐year‐old Japanese woman. At the age of 57, she started having difficulty performing daily work and developed agraphia. She also exhibited restlessness and loss of interest, and began to speak less. Thereafter, stereotypical behavior, gait disturbance and dysphagia were noted. CT scan demonstrated left‐dominant frontal and temporal lobe atrophy. She died at the age of 72, about 16 years after the onset of symptoms. Neuropathologically, the brain weighed 867 g, and showed remarkable cerebral atrophy with degeneration of the white matter, predominantly in the left dorsal frontal lobe and anterior temporal lobe. Microscopically, severe neuronal loss and gliosis with rarefaction were found in the cerebral cortex, and severe destruction of myelin and axons was observed in the cerebral white matter. Moderate neuronal loss with gliosis was also found in the pallidum and substantia nigra. Gallyas‐Braak staining and tau immunostaining revealed pretangle neurons, NFTs, ballooned neurons and astrocytic plaques in the cerebral cortex, subcortical nuclei and brainstem, and argyrophilic threads and coiled bodies in the subcortical white matter. Tau isoform‐specific immunostaining revealed that most tau‐immunoreactive structures were positive for 4‐repeat (4R) tau, but some of the NFTs were positive for 3‐repeat (3R) tau in the cerebral neocortex. Immunoblotting demonstrated an accumulation of 4R tau in the cerebral cortex and subcortical white matter. The patient was pathologically diagnosed as having corticobasal degeneration. Her long survival course likely accounts for the severe white matter degeneration and accumulation of 3R tau in NFTs.  相似文献   
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