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991.
Jeffrey M. Lieblich Alan D. Rogol Beverly J. White Saul W. Rosen 《The American journal of medicine》1982,73(4):506-519
We have studied 23 patients (14 men, nine women) in 18 kindreds with anosmia and hypogonadotropic hypogonadism. Seven kindreds had more than one affected member, and included five eugonadal persons with anosmia and two eusomic women with hypogonadotropic hypogonadism. Other clinical abnormalities observed included: obesity (in nine), cryptorchidism (six), osteopenia (six), mild neurosensory hearing loss (five), gynecomastia (five), diabetes mellitus (four), cleft lip or palate or both (three), high-arched palate (two), short fourth metacarpal (two), and clinodactyly, camptodactyly, shortened frenulum of the tongue, multiple facial anomalies, right-sided aortic arch, malrotation of the gut, renal diverticulum, and mild red-green color blindness (one each).Normal secondary sex characteristics developed in all 20 patients treated on a long-term basis with chorionic gonadotropin or gonadal steroids. Responses to a single injection of gonadotropin-releasing hormone were heterogeneous. Five men had no luteinizing hormone response, five had a depressed response, and one an exaggerated response; two had no follicle-stimulating hormone response, five responses were depressed, three were normal, and one was ex-aggerated. None of seven women achieved a normal luteinizing hormone response to gonadotropin-releasing hormone; two had depressed follicle-stimulating hormone response, four responses were normal, and one was exaggerated. None of 11 patients tested responded to clomiphene. Two men fathered children. Each of two other men who underwent biopsy of the testes before and after long-term chorionic gonadotropin therapy showed mildly increased spermatogenesis. Little or no maturation beyond primordial follicles was observed in two ovarian biopsy specimens. Fifteen of 17 patients had normal basal prolactin levels and 14 of 16 had normal thyrotropin-releasing hormone-induced prolactin increase, but nine of 15 tested had a decreased or absent response of prolactin to chlorpromazine. Circulating concentrations of thyroid hormones were normal, but four of 17 patients tested had depressed TSH (thyroid-stimulating hormone) responses to thyrotropin-releasing hormone, and one man had an exaggerated response. Three of 12 patients had a depressed cortisol response to insulin-induced hypoglycemia, and two of seven patients had slightly depressed deoxycortisol responses to metyrapone. Growth hormone and vasopressin release in all 14 and all 12 patients, respectively, studied were essentially normal.Patients with anosmia and hypogonadotropic hypogonadism may have hypothalamic defect(s) responsible for the hypogonadotropism and perhaps for certain additional deficiencies of anterior pituitary function found in some. The cause of less frequent phenotypic abnormalities has not been established. In certain pedigrees, the evidence suggests that the major manifestations of the syndrome are inherited as an autosomal recessive trait. 相似文献
992.
Alan F Hofmann 《Gastroenterology》2003,125(4):1280-1281
993.
Furst DE Saag K Fleischmann MR Sherrer Y Block JA Schnitzer T Rutstein J Baldassare A Kaine J Calabrese L Dietz F Sack M Senter RG Wiesenhutter C Schiff M Stein CM Satoi Y Matsumoto A Caldwell J Harris RE Moreland LW Hurd E Yocum D Stamler DA 《Arthritis and rheumatism》2002,46(8):2020-2028
OBJECTIVE: To assess the efficacy, safety, and optimal dose of tacrolimus monotherapy in patients with rheumatoid arthritis (RA). METHODS: This phase II, randomized, double-blind, placebo-controlled monotherapy study was set in 12 community sites and 9 university-based sites. Two hundred sixty-eight patients with RA who were resistant to or intolerant of methotrexate (mean dose 15.2 mg/week) and had active disease for at least 6 months (mean tender joint count 28.2, mean erythrocyte sedimentation rate 46.5 mm/hour) were randomized to receive treatment after discontinuation of methotrexate. Those who received at least 1 dose of tacrolimus were analyzed; 141 completed the study. Stable dosages of nonsteroidal antiinflammatory drugs and low-dose prednisone were allowed during treatment. All patients were given 1, 3, or 5 mg of tacrolimus or placebo once daily for 24 weeks. The American College of Rheumatology definition of 20% improvement (ACR20) and the tender and swollen joint counts at the end of treatment were the primary outcomes. RESULTS: ACR20 response rates demonstrated a clear dose response. The ACR20 response was observed in 15.5% of patients receiving placebo (95% confidence interval [95% CI] 7.1-23.9%), 29% of the 1 mg tacrolimus group (95% CI 18.3-39.7%) (P < 0.058); 34.4% of the 3 mg group (95% CI 22.7-46.0%) (P < 0.013), and 50% of the 5 mg group (95% CI 37.8-62.3%) (P < or = 0.001). The tender joint count improved statistically significantly in all tacrolimus groups. The swollen joint count, physical function, and patient-assessed pain improved statistically significantly in the 3 mg and 5 mg groups. The incidence of creatinine elevation > or =40% above baseline levels increased in a dose-dependent manner. Dropout rates were high (41-59%) and were more common for inefficacy in the placebo patients (71.4%), whereas they were more common for toxicity in the high-dose tacrolimus groups (31-33%). Discontinuation for creatinine elevation occurred in the 3 mg (3.1%) and 5 mg (10.9%) tacrolimus groups. CONCLUSION: Tacrolimus improved disease activity in methotrexate-resistant or -intolerant patients with RA. A dose response was observed when efficacy and toxicity were assessed at different doses. The optimal dose of tacrolimus appears to be >1 mg but < or=3 mg daily. 相似文献
994.
Stephen M. Sentovich M.D. Dr. Garnet J. Blatchford M.D. Lucian J. Rivela M.D. Kevin Lin M.D. Alan G. Thorson M.D. Mark A. Christensen M.D. 《Diseases of the colon and rectum》1997,40(12):1430-1434
PURPOSE: This study was undertaken to evaluate how well anorectal manometry and transanal ultrasonography diagnose anal sphincter injury. METHODS: Anorectal manometry and transanal ultrasonography were performed in 20 asymptomatic nulliparous women and 20 asymptomatic parous women, and the results were compared with those obtained in 31 incontinent women who subsequently underwent sphincteroplasty and, thus, had operatively verified anal sphincter injury. By using computerized manometry analysis, mean maximum resting and squeeze pressures, sphincter length, and vector symmetry were determined in all women. All transanal ultrasounds were interpreted blinded as to the patient's history, physical examination, and manometry results. RESULTS: Manometric resting and squeeze pressures were significantly higher in the asymptomatic nulliparous women than in the asymptomatic parous women, and both groups had significantly higher pressures than the incontinent women (
P
<0.001). Anal sphincter length and vector symmetry index were significantly decreased in incontinent women compared with asymptomatic women (
P
<0.01). Decreased resting and squeeze pressures suggestive of possible sphincter injury were found in 90 percent of incontinent women with known anal sphincter injury. Decreased anal sphincter length and vector symmetry were found in only 42 percent of women with known anal sphincter injury. Transanal ultrasound was able to identify 100 percent of the known sphincter injuries but also falsely diagnosed injury in 10 percent of the asymptomatic nulliparous women with intact anal sphincters. False identification of sphincter injury increased when transanal ultrasound scanning was performed proximal to the distal 1.5 cm of the anal canal. CONCLUSION: Although nonspecific, decreased resting and squeeze pressures were found in 90 percent of patients with anal sphincter injury. Decreased anal sphincter length or vector symmetry index were present in only 42 percent of patients with known sphincter injury. When limited to the distal 1.5 cm of the anal canal, transanal ultrasound identified all known sphincter injuries but falsely identified injury in 10 percent of women with intact anal sphincters. Transanal ultrasound in combination with decreased anal pressures correctly identified all intact sphincters and 90 percent of known anal sphincter injuries.Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994. Winner of the New England Society of Colon and Rectal Surgeons Award. 相似文献
995.
An inherited p53 mutation that contributes in a tissue-specific manner to pediatric adrenal cortical carcinoma 总被引:5,自引:0,他引:5 下载免费PDF全文
Ribeiro RC Sandrini F Figueiredo B Zambetti GP Michalkiewicz E Lafferty AR DeLacerda L Rabin M Cadwell C Sampaio G Cat I Stratakis CA Sandrini R 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(16):9330-9335
The incidence of pediatric adrenal cortical carcinoma (ACC) in southern Brazil is 10-15 times higher than that of pediatric ACC worldwide. Because childhood ACC is associated with Li-Fraumeni syndrome, we examined the cancer history and p53 status of 36 Brazilian patients and their families. Remarkably, 35 of 36 patients had an identical germ-line point mutation of p53 encoding an R337H amino acid substitution. Differences within intragenic polymorphic markers demonstrated that at least some mutant alleles arose independently, thus eliminating a founder effect. In tumor cells, the wild-type allele was deleted, and mutant p53 protein accumulated within the nuclei. Although these features are consistent with Li-Fraumeni syndrome-associated adrenal tumors, there was no history of increased cancer incidence among family members. Therefore, this inherited R337H p53 mutation represents a low-penetrance p53 allele that contributes in a tissue-specific manner to the development of pediatric ACC. 相似文献
996.
Dramatic acceleration of protein folding by stabilization of a nonnative backbone conformation 下载免费PDF全文
Di Nardo AA Korzhnev DM Stogios PJ Zarrine-Afsar A Kay LE Davidson AR 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(21):7954-7959
Through a mutagenic investigation of Gly-48, a highly conserved position in the Src homology 3 domain, we have discovered a series of amino acid substitutions that are highly destabilizing, yet dramatically accelerate protein folding, some up to 10-fold compared with the wild-type rate. The unique folding properties of these mutants allowed for accurate measurement of their folding and unfolding rates in water with no denaturant by using an NMR spin relaxation dispersion technique. A strong correlation was found between beta-sheet propensity and the folding rates of the Gly-48 mutants, even though Gly-48 lies in an unusual non-beta-strand backbone conformation in the native state. This finding indicates that the accelerated folding rates of the Gly-48 mutants are the result of stabilization of a nonnative beta-strand conformation in the transition-state structure at this position, thus providing the first, to our knowledge, experimentally elucidated example of a mechanism by which folding can occur fastest through a nonnative conformation. We also demonstrate that residues that are most stabilizing in the transition-state structure are most destabilizing in the native state, and also cause the greatest reductions in in vitro functional activity. These data indicate that the unusual native conformation of the Gly-48 position is important for function, and that evolutionary selection for function can result in a domain that folds at a rate far below the maximum possible. 相似文献
997.
Alan Woelfel Roy A. Kaplan Charles Y.C. Pak 《Metabolism: clinical and experimental》1977,26(2):201-205
The effect of hydrochlorothiazide on the formation of renal stones was evaluated by quantitative assessment of the propensity of urine to undergo crystallization of calcium oxalate. In seven patients with calcium urolithiasis (three with absorptive hypercalciuria, one with renal hypercalciuria, and three with normocalciuric nephrolithiasis), the urinary activity product ratio and formation product ratio of calcium oxalate were measured both on and off therapy with hydrochlorothiazide (50 mg orally twice a day). The activity product ratio (state of saturation with respect to calcium oxalate) decreased in the majority of cases, primarily as a result of the fall in urinary calcium. The formation product ratio (limit of metastability) increased in all cases; the cause of the increase was not readily apparent. Both changes reduced the propensity of urine to undergo crystallization of calcium oxalate, and therefore may account for the clinical improvement reported during thiazide therapy in nephrolithiasis. 相似文献
998.
999.
Melvin H. Freedman Amos Cohen Tom Grunberger Nancy Bunin Ruth E. Luddy E. Fred Saunders Nasrollah Shahidi Alan Lau Zeev Estrov 《British journal of haematology》1992,80(1):40-48
In previous studies on patients with juvenile chronic myelogenous leukaemia (JCML), we found excessive proliferation of malignant monocyte-macrophage elements in the absence of exogenous growth factor, and impaired growth of normal haematopoietic progenitors. In the current study, six newly-diagnosed JCML patients were investigated to characterize the disease further. In co-cultures, JCML cell culture supernatant as well as patient plasma obtained at diagnosis produced a striking reduction in numbers of control marrow BFU-E, CFU-GM, CFU-Meg and CFU-GEMM colonies. Monoclonal anti-tumour necrosis factor alpha neutralizing antibodies (anti-TNF-alpha Ab) abolished these inhibitory properties. In sharp contrast, JCML supernatants exerted a marked growth-promoting effect on autologous JCML cells cultured in clonogenic assays. Anti-TNF-alpha Ab and anti-granulocyte-macrophage colony-stimulating factor neutralizing antibodies (anti-GM-CSF Ab) both reversed the stimulating effect. Recombinant GM-CSF and recombinant TNF alpha produced a profound increase in JCML colonies when tested individually and anti-GM-CSF Ab reversed the TNF-alpha effect. Expression studies of TNF-alpha and TNF-alpha receptor genes of cultured JCML cells demonstrated mRNAs for both. Further, TNF-alpha activity was assayed in a wide variety of cell culture supernatants and in normal and patients' plasma, and only the JCML specimens showed increased TNF-alpha values. Recombinant interleukin-1 alpha (IL-1 alpha) also stimulated JCML colony growth, but polyclonal anti-IL-1 neutralizing antibodies did not suppress JCML colony numbers nor did it reverse the effects of TNF-alpha or GM-CSF. The evidence indicated that the JCML monokine which inhibits normal haematopoiesis is TNF-alpha and that the endogenously-produced TNF-alpha and GM-CSF from JCML cells play an important role in the pathogenesis of the disease by acting as autocrine growth factors. IL-1 alpha also stimulates JCML cell proliferation as an accessory factor and augments the effect of GM-CSF, TNF-alpha or both. 相似文献
1000.
Toh CH Samis J Downey C Walker J Becker L Brufatto N Tejidor L Jones G Houdijk W Giles A Koschinsky M Ticknor LO Paton R Wenstone R Nesheim M 《Blood》2002,100(7):2522-2529
A decrease in light transmittance before clot formation, manifesting as a biphasic waveform (BPW) pattern in coagulation assays, was previously correlated with the onset of disseminated intravascular coagulation (DIC). In this study of 1187 consecutive admissions to the intensive care unit, the degree of this change on admission predicts DIC better than D-dimer measurements. Additionally, the BPW preceded the time of DIC diagnosis by 18 hours, on average, in 56% (203 of 362) of DIC patients. The BPW is due to the rapid formation of a precipitate and coincident turbidity change on recalcification of plasma. The isolated precipitate contains very-low-density lipoprotein (VLDL) and C-reactive protein (CRP). The addition of CRP and Ca(++) to normal plasma also causes the precipitation of VLDL and IDL, but not LDL or HDL. The K(d) of the CRP/VLDL interaction is 340 nM, and the IC(50) for Ca(++) is 5.0 mM. In 15 plasmas with the BPW, CRP was highly elevated (77-398 microg/mL), and the concentration of isolated VLDL ranged from 0.082 to 1.32 mM (cholesterol). The turbidity change on recalcification correlates well with the calculated level of the CRP-VLDL complex. Clinically, the BPW better predicts for DIC than either CRP or triglyceride alone. The complex may have pathophysiological implications because CRP can be detected in the VLDL fraction from sera of patients with the BPW, and the VLDL fraction has enhanced prothrombinase surface activity. The complex has been designated lipoprotein complexed C-reactive protein. 相似文献