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151.
OBJECTIVE: The authors investigated the integrity and function of nervus stapedius 1 year after facial paralysis. STUDY DESIGN: Patients with Bell's palsy were observed prospectively for 1 year and compared with healthy patients. SETTING: The follow-up of patients was done in the outpatient clinic and tests were applied in the audiology unit. PATIENTS: The mean age of 32 patients was 41.03 years. Eight of 32 patients were grade II (25%), 11 were grade III (35%), and 13 were grade IV (40%) according to House-Brackman grading system. The mean age of the control group (10 persons) was 36.5 years. INTERVENTION: Contralateral stimulus was used in acoustic reflex test at 500 and 1,000 Hz with 80-, 90-, 100-, and 110-dB stimulus intensity. Tests were applied in three ways: normal position, eye-closed position, and grin position. Tests were done in the first 15 days of facial paralysis and repeated at least 1 year thereafter. The millimeter difference in amplitude of impedance recording of middle ear between the normal ear and paralyzed ear was accepted as criterion. MAIN OUTCOME MEASURES: There were 6- to 9-mm amplitude differences between normal side and healed side of grade IV patients with 100- and 110-dB stimuli. RESULTS: In the second test (after 1 year), statistically significant differences were present between control group and grade IV patients on 1,000 and 500 Hz frequencies with 100- and 110-dB stimulus intensity (p < 0.05). There were no significant differences between grade II and control group and between grade III and control group. CONCLUSIONS: A permanent partial denervation is present on the stapedial nerve, especially after grade IV paralysis, and it affects the function of stapes muscle in high decibel sounds. But it does not affect the stapes reflex threshold. No synkinetic innervation was found in the authors' patient group with their test method.  相似文献   
152.
A minimal model of glycogen metabolism in muscle tissue is analyzed in accordance with metabolic control analysis. The model contains two branch points. Rather than contributing to complexity of the analysis, this branching allows expression of the control coefficients in a simplified form. Glucose 6-phosphate is the metabolite at the first branch point, and the analysis is simplified further by the fact that glucose 6-phosphate is the substrate for enzymes which catalyze near-equilibrium reactions. Control of the concentration of glucose 6-phosphate is of interest because of its pivotal location in the metabolic system, but also because it interacts with an allosteric site on glycogen synthase to stimulate glycogen synthase activity. It is shown that the control which the transporter and enzymes involved in glycogen synthesis exert on glycolytic flux is proportional to the control which these components exert on glucose 6-phosphate concentration. Thus, glycolysis plays a major role in control of glucose 6-phosphate concentration. It is concluded that control of glycogen synthesis is not a rigid parameter of any component of this metabolic system. Rather the distribution of control is flexible and shifts from one portion of the system to another in response to shifts in the physiological state. An important element in determining the distribution of control of glycogen synthesis is the change in the sensitivity of the allosteric site of glycogen synthase to glucose 6-phosphate which is brought about by conversion of glycogen synthase to the dephosphorylated, glucose 6-phosphate-independent, state.  相似文献   
153.
The tissue and plasma proteolysis changes were studied up on white laboratory rats while the pancreas zone galvanization using electrical field of 0.01-0.05-0.10 mA/cm2 density during 60 minutes. It was established that intratissue electrophoresis with contrykal lowers the low molecular mass peptides lysis by 6.6 times, the high molecular mass peptides-by 4.4, collagen-by 3.  相似文献   
154.
Hepatitis A is the most frequently reported vaccine-preventable disease in the United States. Hepatitis A incidence and risk factors during 1983-1995 were examined among cases reported to the study's Sentinel Counties: Denver County, Colorado; Pierce County, Washington; Jefferson County, Alabama; and Pinellas County, Florida. Of 4897 serologically confirmed cases, 611 patients (13%) were hospitalized and 9 (0.2%) died. The average incidence was 14.7/100, 000 (range, 0.6-100.7/100,000, depending on county and year). The frequency of reported sources of infection varied by county, but the largest single group overall (52%) did not report a source. During 3-year communitywide outbreaks in Denver (1991-1993) and Pierce (1987-1989) Counties, rates increased 4- and 13-fold, respectively, and increased in all age, racial/ethnic, and risk groups. During communitywide outbreaks, hepatitis A is not limited to specific risk groups; sustained nationwide reductions in incidence are more likely to result from routine childhood vaccination than from targeted vaccination of high-risk groups.  相似文献   
155.
In 1990, Drs Millard and Latham published their initial experience with dynamic maxillary appliances (DMAs) and periosteoplasty for children with cleft lip and palate. The technique provided for alveolar alignment and consolidation, with elimination of oronasal fistulas. Opponents to this approach speculated about impairments to facial growth. To date no longitudinal studies have been published. Over the last 10 years, 35 unilateral and 10 bilateral complete clefts have been treated with this technique. All patients have been followed and documented clinically, orthodontically, and radiographically. Cephalometric analyses were performed on children after the age of 6 years. The children have excellent facial aesthetics with well-balanced lips and noses. Radiographs demonstrate bone within the repaired alveolar clefts. Articulated impressions show anterior and lateral crossbites in the unilateral patients that improve over time and appear to be correctable orthodontically. The bilateral patients have satisfactory occlusions and arch forms. Cephalometric analyses confirmed no evidence of skeletal crossbites or midfacial growth retardation. This is a work in progress that will continue as the children grow. Although definite and final conclusions would be premature, it can be stated that to date all patients are following consistent and favorable growth patterns. Our team is confident in proceeding with this technique.  相似文献   
156.
The salivary glands participate in systemic illnesses because they are secretory structures allied with the gastrointestinal tract. Thus they are involved in systemic inflammatory, allergic, and neoplastic conditions. Perhaps the most common condition is that of mumps in the acute phase. Of the chronic diseases, Mikulicz's disease or Sj?gren's syndrome is most frequently noted. In most instances of systemic involvement, the salivary gland enlargement is the rule, with the gland being tense, soft, and enlarged, and with progressive growth over a period of time. Usually all glands are involved. The diagnosis should be suspected from the history and the physical examination, noting that all the glands are equally involved by the enlargement. If there is any question, a biopsy should be performed. In the case of Sj?gren's syndrome, the biopsy specimen may be taken either from a major salivary gland or from one of the minor ones, or the nasal mucous membrane or oral cavity. In general, definitive therapy is unsuccessful for the systemic illness involving the salivary glands, and in most instances has to be supportive.  相似文献   
157.
The influence of stress-induced corticosteroid production on gastric ulceration, blood flow velocity in gastric microvessels and blood pressure was studied in rats. The role of plasma corticosteroids was investigated by means of blockade of the pituitary-adrenocortical system (PACS) and following corticosterone replacement therapy (400 mu/100 g b.w.). The blockade which was induced by Fi. hydrocortisone administration (7 days before stress, 30 mg/100 g b. w.) resulted in an insufficient corticosteroid production. To evaluate the influence of corticosteroids on blood flow velocity in gastric microvessels of muscular, submucosal and mucosal coats it was used intravital microfilming by means of a dark-field contact epiobjective. Stress (water immersion + restraint) induces an ulceration, a decrease in the systemic arterial blood pressure (3 h after stress onset) and a decrease in blood flow velocity in the gastric microvessels (3 h after stress onset). In rats with insufficient corticosteroid production stress-induced ulceration, a decrease in blood pressure and gastric blood velocity were more greater than in rats with intact PACS. Replacement corticosterone therapy corrected all parameters. The results revealed that antiulcerogenic effect of stress-induced glucocorticoid production is realised owing to normalisation of gastric blood supply which is provided by an increase in systemic blood pressure.  相似文献   
158.
We report two cases of vasospastic angina associated with anaphylactic reaction caused by nonsteroidal anti-inflammatory drugs (NSAIDs). Both patients exhibited anaphylactic manifestations, such as general rash and urticaria, along with angina pectoris with electrocardiographic ST-segment elevations after suppository administration of diclofenac sodium or indomethacin, the most commonly used NSAIDs. Although these patients had normal coronary arteriograms, intracoronary administration of ergonovine or acetylcholine provoked diffuse coronary artery spasms accompanied by chest pain and ischemic ST-segment changes. It is therefore suggested that an allergic mechanism may be involved as a causative factor of the coronary artery spasm induced by NSAIDs.  相似文献   
159.
Exposure of rats to 2 hours of cold water restraint is associated with both macroscopic and microscopic gastric mucosal injury. Administration of neurotensin into the lateral ventricle or into the nucleus accumbens, one of the mesolimbic dopamine system nuclei, is associated with protection when given before exposure to cold water restraint. Under conditions of cold water restraint, pretreatment with central neurotensin is associated with maintenance of gastric mucosal blood flow and an increase in endogenous gastric mucosal PGE2 activity. In addition, pretreatment with 6-hydroxy dopamine into the mesolimbic nuclei, which depletes them of endogenous dopamine, prior to exposure to cold water restraint, ameliorates the protective effect of central neurotensin. Centrally administered neurotensin inhibits basal, pentagastrin-, carbachol-, and 2-deoxy-D-glucose-induced but not histamine-induced gastric acid secretion. This antisecretory effect is ameliorated by parenteral pretreatment with haloperidol and domperidone. Taken together, these observations support the hypothesis that centrally administered neurotensin, particularly into the nuclei of the mesolimbic dopamine system, confers protection against gastric mucosal injury produced by 2 hours of cold water restraint. This affect may be due, in part, to inhibition of acid secretion and maintenance of mucosal blood flow mediated by an increase in gastric mucosal PGE2 activity.  相似文献   
160.
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